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Liu Y, Lo JHY, Nunes JK, Stone HA, Shum HC. High-throughput measurement of elastic moduli of microfibers by rope coiling. Proc Natl Acad Sci U S A 2024; 121:e2303679121. [PMID: 38478687 PMCID: PMC10962939 DOI: 10.1073/pnas.2303679121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2023] [Accepted: 02/05/2024] [Indexed: 03/27/2024] Open
Abstract
There are many fields where it is of interest to measure the elastic moduli of tiny fragile fibers, such as filamentous bacteria, actin filaments, DNA, carbon nanotubes, and functional microfibers. The elastic modulus is typically deduced from a sophisticated tensile test under a microscope, but the throughput is low and limited by the time-consuming and skill-intensive sample loading/unloading. Here, we demonstrate a simple microfluidic method enabling the high-throughput measurement of the elastic moduli of microfibers by rope coiling using a localized compression, where sample loading/unloading are not needed between consecutive measurements. The rope coiling phenomenon occurs spontaneously when a microfiber flows from a small channel into a wide channel. The elastic modulus is determined by measuring either the buckling length or the coiling radius. The throughput of this method, currently 3,300 fibers per hour, is a thousand times higher than that of a tensile tester. We demonstrate the feasibility of the method by testing a nonuniform fiber with axially varying elastic modulus. We also demonstrate its capability for in situ inline measurement in a microfluidic production line. We envisage that high-throughput measurements may facilitate potential applications such as screening or sorting by mechanical properties and real-time control during production of microfibers.
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Affiliation(s)
- Yuan Liu
- Department of Mechanical Engineering, University of Hong Kong, Hong Kong SAR, China
| | - Jack H. Y. Lo
- Center for Integrative Petroleum Research, College of Petroleum Engineering and Geosciences, King Fahd University of Petroleum and Minerals, Dhahran31261, Saudi Arabia
| | - Janine K. Nunes
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ08544
| | - Howard A. Stone
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ08544
| | - Ho Cheung Shum
- Department of Mechanical Engineering, University of Hong Kong, Hong Kong SAR, China
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Chan CWF, Wang B, Nan L, Huang X, Mao T, Chu HY, Luo C, Chu H, Choi GCG, Shum HC, Wong ASL. Author Correction: High-throughput screening of genetic and cellular drivers of syncytium formation induced by the spike protein of SARS-CoV-2. Nat Biomed Eng 2024; 8:336. [PMID: 38267642 DOI: 10.1038/s41551-024-01177-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2024]
Affiliation(s)
- Charles W F Chan
- Laboratory of Combinatorial Genetics and Synthetic Biology, School of Biomedical Sciences, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Centre for Oncology and Immunology, Hong Kong Science Park, Shatin, Hong Kong SAR, China
| | - Bei Wang
- Laboratory of Combinatorial Genetics and Synthetic Biology, School of Biomedical Sciences, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Centre for Oncology and Immunology, Hong Kong Science Park, Shatin, Hong Kong SAR, China
| | - Lang Nan
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, Hong Kong SAR, China
| | - Xiner Huang
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Tianjiao Mao
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, Hong Kong SAR, China
| | - Hoi Yee Chu
- Laboratory of Combinatorial Genetics and Synthetic Biology, School of Biomedical Sciences, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Centre for Oncology and Immunology, Hong Kong Science Park, Shatin, Hong Kong SAR, China
| | - Cuiting Luo
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Hin Chu
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.
- Centre for Virology, Vaccinology and Therapeutics, Hong Kong Science Park, Shatin, Hong Kong SAR, China.
- Department of Infectious Disease and Microbiology, The University of Hong Kong-Shenzhen Hospital, Shenzhen, People's Republic of China.
| | - Gigi C G Choi
- Laboratory of Combinatorial Genetics and Synthetic Biology, School of Biomedical Sciences, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.
- Centre for Oncology and Immunology, Hong Kong Science Park, Shatin, Hong Kong SAR, China.
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, Hong Kong SAR, China.
| | - Alan S L Wong
- Laboratory of Combinatorial Genetics and Synthetic Biology, School of Biomedical Sciences, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.
- Centre for Oncology and Immunology, Hong Kong Science Park, Shatin, Hong Kong SAR, China.
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Chan CWF, Wang B, Nan L, Huang X, Mao T, Chu HY, Luo C, Chu H, Choi GCG, Shum HC, Wong ASL. High-throughput screening of genetic and cellular drivers of syncytium formation induced by the spike protein of SARS-CoV-2. Nat Biomed Eng 2024; 8:291-309. [PMID: 37996617 DOI: 10.1038/s41551-023-01140-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 10/18/2023] [Indexed: 11/25/2023]
Abstract
Mapping mutations and discovering cellular determinants that cause the spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to induce infected cells to form syncytia would facilitate the development of strategies for blocking the formation of such cell-cell fusion. Here we describe high-throughput screening methods based on droplet microfluidics and the size-exclusion selection of syncytia, coupled with large-scale mutagenesis and genome-wide knockout screening via clustered regularly interspaced short palindromic repeats (CRISPR), for the large-scale identification of determinants of cell-cell fusion. We used the methods to perform deep mutational scans in spike-presenting cells to pinpoint mutable syncytium-enhancing substitutions in two regions of the spike protein (the fusion peptide proximal region and the furin-cleavage site). We also used a genome-wide CRISPR screen in cells expressing the receptor angiotensin-converting enzyme 2 to identify inhibitors of clathrin-mediated endocytosis that impede syncytium formation, which we validated in hamsters infected with SARS-CoV-2. Finding genetic and cellular determinants of the formation of syncytia may reveal insights into the physiological and pathological consequences of cell-cell fusion.
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Affiliation(s)
- Charles W F Chan
- Laboratory of Combinatorial Genetics and Synthetic Biology, School of Biomedical Sciences, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Centre for Oncology and Immunology, Hong Kong Science Park, Shatin, Hong Kong SAR, China
| | - Bei Wang
- Laboratory of Combinatorial Genetics and Synthetic Biology, School of Biomedical Sciences, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Centre for Oncology and Immunology, Hong Kong Science Park, Shatin, Hong Kong SAR, China
| | - Lang Nan
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, Hong Kong SAR, China
| | - Xiner Huang
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Tianjiao Mao
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, Hong Kong SAR, China
| | - Hoi Yee Chu
- Laboratory of Combinatorial Genetics and Synthetic Biology, School of Biomedical Sciences, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
- Centre for Oncology and Immunology, Hong Kong Science Park, Shatin, Hong Kong SAR, China
| | - Cuiting Luo
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Hin Chu
- State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.
- Centre for Virology, Vaccinology and Therapeutics, Hong Kong Science Park, Shatin, Hong Kong SAR, China.
- Department of Infectious Disease and Microbiology, The University of Hong Kong-Shenzhen Hospital, Shenzhen, People's Republic of China.
| | - Gigi C G Choi
- Laboratory of Combinatorial Genetics and Synthetic Biology, School of Biomedical Sciences, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.
- Centre for Oncology and Immunology, Hong Kong Science Park, Shatin, Hong Kong SAR, China.
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, Hong Kong SAR, China.
| | - Alan S L Wong
- Laboratory of Combinatorial Genetics and Synthetic Biology, School of Biomedical Sciences, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.
- Centre for Oncology and Immunology, Hong Kong Science Park, Shatin, Hong Kong SAR, China.
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Doshi N, Guo W, Chen F, Venema P, Shum HC, de Vries R, Li X. Simple and complex coacervation in systems involving plant proteins. Soft Matter 2024; 20:1966-1977. [PMID: 38334990 DOI: 10.1039/d3sm01275a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/10/2024]
Abstract
Plant-based foods are gaining popularity as alternatives to meat and dairy products due to sustainability and health concerns. As a consequence, there is a renewed interest in the phase behaviour of plant proteins and of mixtures of plant proteins and polysaccharides, in particular in the cases where coacervation is found to occur, i.e., liquid-liquid phase separation (LLPS) into two phases, one of which is rich in biopolymers and one of which is poor in biopolymer. Here we review recent research into both simple and complex coacervation in systems involving plant proteins, and their applications in food- as well as other technologies, such as microencapsulation, microgel production, adhesives, biopolymer films, and more.
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Affiliation(s)
- Nirzar Doshi
- Physical Chemistry and Soft Matter, Wageningen University and Research, Wageningen 6708 WE, The Netherlands.
- Laboratory of Physics and Physical Chemistry of Foods, Wageningen University, Bornse Weilanden 9, 6708, WG, Wageningen, The Netherlands
| | - Wei Guo
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, New Territories, Shatin, Hong Kong, China
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Feipeng Chen
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Paul Venema
- Laboratory of Physics and Physical Chemistry of Foods, Wageningen University, Bornse Weilanden 9, 6708, WG, Wageningen, The Netherlands
| | - Ho Cheung Shum
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, New Territories, Shatin, Hong Kong, China
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Renko de Vries
- Physical Chemistry and Soft Matter, Wageningen University and Research, Wageningen 6708 WE, The Netherlands.
| | - Xiufeng Li
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, New Territories, Shatin, Hong Kong, China
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing, 210095, Jiangsu, China.
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Nan L, Zhang H, Weitz DA, Shum HC. Development and future of droplet microfluidics. Lab Chip 2024; 24:1135-1153. [PMID: 38165829 DOI: 10.1039/d3lc00729d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2024]
Abstract
Over the past two decades, advances in droplet-based microfluidics have facilitated new approaches to process and analyze samples with unprecedented levels of precision and throughput. A wide variety of applications has been inspired across multiple disciplines ranging from materials science to biology. Understanding the dynamics of droplets enables optimization of microfluidic operations and design of new techniques tailored to emerging demands. In this review, we discuss the underlying physics behind high-throughput generation and manipulation of droplets. We also summarize the applications in droplet-derived materials and droplet-based lab-on-a-chip biotechnology. In addition, we offer perspectives on future directions to realize wider use of droplet microfluidics in industrial production and biomedical analyses.
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Affiliation(s)
- Lang Nan
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China.
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong, China
| | - Huidan Zhang
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA
| | - David A Weitz
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong, China
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China.
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong, China
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Yu Y, Pan Y, Shen Y, Tian J, Zhang R, Guo W, Li C, Shum HC. Vascular network-inspired fluidic system (VasFluidics) with spatially functionalizable membranous walls. Nat Commun 2024; 15:1437. [PMID: 38365901 PMCID: PMC10873510 DOI: 10.1038/s41467-024-45781-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Accepted: 01/31/2024] [Indexed: 02/18/2024] Open
Abstract
In vascular networks, the transport across different vessel walls regulates chemical compositions in blood over space and time. Replicating such trans-wall transport with spatial heterogeneity can empower synthetic fluidic systems to program fluid compositions spatiotemporally. However, it remains challenging as existing synthetic channel walls are typically impermeable or composed of homogeneous materials without functional heterogeneity. This work presents a vascular network-inspired fluidic system (VasFluidics), which is functionalizable for spatially different trans-wall transport. Facilitated by embedded three-dimensional (3D) printing, elastic, ultrathin, and semipermeable walls self-assemble electrostatically. Physicochemical reactions between fluids and walls are localized to vary the trans-wall molecules among separate regions, for instance, by confining solutions or locally immobilizing enzymes on the outside of channels. Therefore, fluid compositions can be regulated spatiotemporally, for example, to mimic blood changes during glucose absorption and metabolism. Our VasFluidics expands opportunities to replicate biofluid processing in nature, providing an alternative to traditional fluidics.
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Affiliation(s)
- Yafeng Yu
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong (SAR), China
| | - Yi Pan
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong (SAR), China
- Institute of Biomedical Engineering, College of Medicine, Southwest Jiaotong University, Chengdu, 610031, China
| | - Yanting Shen
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong (SAR), China
| | - Jingxuan Tian
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong (SAR), China
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong (SAR), China
| | - Ruotong Zhang
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong (SAR), China
| | - Wei Guo
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong (SAR), China
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong (SAR), China
| | - Chang Li
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong (SAR), China
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong (SAR), China.
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong (SAR), China.
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Hu S, Huan X, Yang J, Cui H, Gao W, Liu Y, Yu SF, Shum HC, Kim JT. Three-Dimensionally Printed, Vertical Full-Color Display Pixels for Multiplexed Anticounterfeiting. Nano Lett 2023; 23:9953-9962. [PMID: 37871156 DOI: 10.1021/acs.nanolett.3c02916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
Information encryption strategies have become increasingly essential. Most of the fluorescent security patterns have been made with a lateral configuration of red, green, and blue subpixels, limiting the pixel density and security level. Here we report vertically stacked, luminescent heterojunction micropixels that construct high-resolution, multiplexed anticounterfeiting labels. This is enabled by meniscus-guided three-dimensional (3D) microprinting of red, green, and blue (RGB) dye-doped materials. High-precision vertical stacking of subpixel segments achieves full-color pixels without sacrificing lateral resolution, achieving a small pixel size of ∼μm and a high density of over 13,000 pixels per inch. Furthermore, a full-scale color synthesis for individual pixels is developed by modulating the lengths of the RGB subpixels. Taking advantage of these unique 3D structural designs, trichannel multiplexed anticounterfeiting Quick Response codes are successfully demonstrated. We expect that this work will advance data encryption technology while also providing a versatile manufacturing platform for diverse 3D display devices.
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Affiliation(s)
- Shiqi Hu
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong 999077, China
| | - Xiao Huan
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong 999077, China
| | - Jihyuk Yang
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong 999077, China
| | - Huanqing Cui
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong 999077, China
| | - Wei Gao
- Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong 999077, China
| | - Yu Liu
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong 999077, China
| | - Siu Fung Yu
- Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong 999077, China
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong 999077, China
| | - Ji Tae Kim
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong 999077, China
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Li Q, Song Q, Guo W, Cao Y, Cui X, Chen D, Shum HC. Synthetic Membraneless Droplets for Synaptic-Like Clustering of Lipid Vesicles. Angew Chem Int Ed Engl 2023; 62:e202313096. [PMID: 37728515 DOI: 10.1002/anie.202313096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 09/19/2023] [Accepted: 09/20/2023] [Indexed: 09/21/2023]
Abstract
In eukaryotic cells, the membraneless organelles (MLOs) formed via liquid-liquid phase separation (LLPS) are found to interact intimately with membranous organelles (MOs). One major mode is the clustering of MOs by MLOs, such as the formation of clusters of synaptic vesicles at nerve terminals mediated by the synapsin-rich MLOs. Aqueous droplets, including complex coacervates and aqueous two-phase systems, have been plausible MLO-mimics to emulate or elucidate biological processes. However, neither of them can cluster lipid vesicles (LVs) like MLOs. In this work, we develop a synthetic droplet assembled from a combination of two different interactions underlying the formation of these two droplets, namely, associative and segregative interactions, which we call segregative-associative (SA) droplets. The SA droplets cluster and disperse LVs recapitulating the key functional features of synapsin condensates, which can be attributed to the weak electrostatic interaction environment provided by SA droplets. This work suggests LLPS with combined segregative and associative interactions as a possible route for synaptic clustering of lipid vesicles and highlights SA droplets as plausible MLO-mimics and models for studying and mimicking related cellular dynamics.
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Affiliation(s)
- Qingchuan Li
- School of Chemistry & Chemical Engineering, National Engineering Research Center for Colloidal Materials, Shandong University, 27 Shanda Nanlu, Jinan, Shandong, P.R.China
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong (SAR), Hong Kong, China
| | - Qingchun Song
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Wei Guo
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong (SAR), Hong Kong, China
| | - Yang Cao
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Xinyu Cui
- Department of Public Health, Mudanjiang Medical University, Mudanjiang, 157000, P. R. China
| | - Dairong Chen
- School of Chemistry & Chemical Engineering, National Engineering Research Center for Colloidal Materials, Shandong University, 27 Shanda Nanlu, Jinan, Shandong, P.R.China
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong (SAR), Hong Kong, China
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Li C, Yu Y, Li H, Lin H, Cui H, Pan Y, Zhang R, Song Y, Shum HC. Heterogeneous Self-Assembly of a Single Type of Nanoparticle Modulated by Skin Formation. ACS Nano 2023. [PMID: 37307592 DOI: 10.1021/acsnano.3c02082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Self-assembly of colloidal nanoparticles has generated tremendous interest due to its widespread applications in structural colorations, sensors, and optoelectronics. Despite numerous strategies being developed to fabricate sophisticated structures, the heterogeneous self-assembly of a single type of nanoparticle in one step remains challenging. Here, facilitated by spatial confinement induced by a skin layer in a drying droplet, we achieve the heterogeneous self-assembly of a single type of nanoparticle by quickly evaporating a colloid-poly (ethylene glycol) (PEG) droplet. During the drying process, a skin layer forms at the droplet surface. The resultant spatial confinement assembles nanoparticles into face-centered-cubic (FCC) lattices with (111) and (100) plane orientations, generating binary bandgaps and two structural colors. The self-assembly of nanoparticles can be regulated by varying the PEG concentration so that FCC lattices with homo- or heterogeneous orientation planes can be prepared on demand. Besides, the approach is applicable for diverse droplet shapes, various substrates, and different nanoparticles. The one-pot general strategy breaks the requirements for multiple types of building blocks and predesigned substrates, extending the fundamental understanding underlying colloidal self-assembly.
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Affiliation(s)
- Chang Li
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Hong Kong (SAR), China
| | - Yafeng Yu
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Hong Kong (SAR), China
| | - Huizeng Li
- Key Laboratory of Green Printing, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Haisong Lin
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Hong Kong (SAR), China
- Advanced Biomedical Instrumentation Center, Hong Kong Science Park, Shatin, New Territories, Hong Kong (SAR), China
| | - Huanqing Cui
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Hong Kong (SAR), China
| | - Yi Pan
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Hong Kong (SAR), China
| | - Ruotong Zhang
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Hong Kong (SAR), China
| | - Yanlin Song
- Key Laboratory of Green Printing, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Ho Cheung Shum
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Hong Kong (SAR), China
- Advanced Biomedical Instrumentation Center, Hong Kong Science Park, Shatin, New Territories, Hong Kong (SAR), China
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10
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Chen F, Li X, Yu Y, Li Q, Lin H, Xu L, Shum HC. Phase-separation facilitated one-step fabrication of multiscale heterogeneous two-aqueous-phase gel. Nat Commun 2023; 14:2793. [PMID: 37193701 DOI: 10.1038/s41467-023-38394-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 04/30/2023] [Indexed: 05/18/2023] Open
Abstract
Engineering heterogeneous hydrogels with distinct phases at various lengths, which resemble biological tissues with high complexity, remains challenging by existing fabricating techniques that require complicated procedures and are often only applicable at bulk scales. Here, inspired by ubiquitous phase separation phenomena in biology, we present a one-step fabrication method based on aqueous phase separation to construct two-aqueous-phase gels that comprise multiple phases with distinct physicochemical properties. The gels fabricated by this approach exhibit enhanced interfacial mechanics compared with their counterparts obtained from conventional layer-by-layer methods. Moreover, two-aqueous-phase gels with programmable structures and tunable physicochemical properties can be conveniently constructed by adjusting the polymer constituents, gelation conditions, and combining different fabrication techniques, such as 3D-printing. The versatility of our approach is demonstrated by mimicking the key features of several biological architectures at different lengths: macroscale muscle-tendon connections; mesoscale cell patterning; microscale molecular compartmentalization. The present work advances the fabrication approach for designing heterogeneous multifunctional materials for various technological and biomedical applications.
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Affiliation(s)
- Feipeng Chen
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong (SAR), China
| | - Xiufeng Li
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong (SAR), China
| | - Yafeng Yu
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong (SAR), China
| | - Qingchuan Li
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong (SAR), China
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong (SAR), China
| | - Haisong Lin
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong (SAR), China
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong (SAR), China
| | - Lizhi Xu
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong (SAR), China
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong (SAR), China
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong (SAR), China.
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong (SAR), China.
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11
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Abbasi N, Nunes JK, Pan Z, Dethe T, Shum HC, Košmrlj A, Stone HA. Flows of a nonequilibrated aqueous two-phase system in a microchannel. Soft Matter 2023; 19:3551-3561. [PMID: 37144458 DOI: 10.1039/d3sm00233k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Liquid-liquid phase separation is a rich and dynamic process, which recently has gained new interest, especially in biology and for material synthesis. In this work, we experimentally show that co-flow of a nonequilibrated aqueous two-phase system within a planar flow-focusing microfluidic device results in a three-dimensional flow, as the two nonequilibrated solutions move downstream along the length of the microchannel. After the system reaches steady-state, invasion fronts from the outer stream are formed along the top and bottom walls of the microfluidic device. The invasion fronts advance towards the center of the channel, until they merge. We first show by tuning the concentration of polymer species within the system that the formation of these fronts is due to liquid-liquid phase separation. Moreover, the rate of invasion from the outer stream increases with increasing polymer concentrations in the streams. We hypothesize the invasion front formation and growth is driven by Marangoni flow induced by the polymer concentration gradient along the width of the channel, as the system is undergoing phase separation. In addition, we show how at various downstream positions the system reaches its steady-state configuration once the two fluid streams flow side-by-side in the channel.
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Affiliation(s)
- Niki Abbasi
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ, USA.
| | - Janine K Nunes
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ, USA.
| | - Zehao Pan
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ, USA.
| | - Tejas Dethe
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ, USA.
| | - Ho Cheung Shum
- Department of Mechanical Engineering, University of Hong Kong, Hong Kong, China
| | - Andrej Košmrlj
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ, USA.
- Princeton Materials Institute, Princeton University, Princeton, NJ, USA
| | - Howard A Stone
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ, USA.
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12
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Shen Y, Liu Y, Nunes JK, Wang C, Xu M, To MKT, Stone HA, Shum HC. Fibro-Gel: An All-Aqueous Hydrogel Consisting of Microfibers with Tunable Release Profile and its Application in Wound Healing. Adv Mater 2023; 35:e2211637. [PMID: 36789886 DOI: 10.1002/adma.202211637] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 02/06/2023] [Indexed: 05/12/2023]
Abstract
Injectable hydrogels are valuable tools in tissue engineering and regenerative medicine due to their unique advantages of injectability with minimal invasiveness and usability for irregularly shaped sites. However, it remains challenging to achieve scalable manufacturing together with matching physicochemical properties and on-demand drug release for a high level of control over biophysical and biomedical cues to direct endogenous cells. Here, the use of an injectable fibro-gel is demonstrated, a water-filled network of entangled hydrogel microfibers, whose physicochemical properties and drug release profiles can be tailored to overcome these shortcomings. This fibro-gel exhibits favorable in vitro biocompatibility and the capability to aid vascularization. The potential use of the fibro-gel for advancing tissue regeneration is explored with a mice excision skin model. Preliminary in vivo tests indicate that the fibro-gel promotes wound healing and new healthy tissue regeneration at a faster rate than a commercial gel. Moreover, it is demonstrated that the release of distinct drugs at different rates can further accelerate wound healing with higher efficiency, by using a two-layer fibro-gel model. The combination of injectability and tailorable properties of this fibro-gel offers a promising approach in biomedical fields such as therapeutic delivery, medical dressings, and 3D tissue scaffolds for tissue engineering.
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Affiliation(s)
- Yanting Shen
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China
| | - Yuan Liu
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China
| | - Janine K Nunes
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ, 08544, USA
| | - Chenmin Wang
- Department of Orthopaedics and Traumatology, LKS Faculty of Medicine, University of Hong Kong, Pokfulam Road, Hong Kong SAR, China
| | - Miao Xu
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China
| | - Michael K T To
- Department of Orthopaedics and Traumatology, LKS Faculty of Medicine, University of Hong Kong, Pokfulam Road, Hong Kong SAR, China
| | - Howard A Stone
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ, 08544, USA
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China
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13
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Kiang KMY, Tang W, Song Q, Liu J, Li N, Lam TL, Shum HC, Zhu Z, Leung GKK. Targeting unfolded protein response using albumin-encapsulated nanoparticles attenuates temozolomide resistance in glioblastoma. Br J Cancer 2023; 128:1955-1963. [PMID: 36927978 PMCID: PMC10147657 DOI: 10.1038/s41416-023-02225-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2022] [Revised: 02/26/2023] [Accepted: 03/01/2023] [Indexed: 03/18/2023] Open
Abstract
BACKGROUND Chemoresistant cancer cells frequently exhibit a state of chronically activated endoplasmic reticulum (ER) stress. Engaged with ER stress, the unfolded protein response (UPR) is an adaptive reaction initiated by the accumulation of misfolded proteins. Protein disulfide isomerase (PDI) is a molecular chaperone known to be highly expressed in glioblastomas with acquired resistance to temozolomide (TMZ). We investigate whether therapeutic targeting of PDI provides a rationale to overcome chemoresistance. METHODS The activity of PDI was suppressed in glioblastoma cells using a small molecule inhibitor CCF642. Either single or combination treatment with TMZ was used. We prepared nanoformulation of CCF642 loaded in albumin as a drug carrier for orthotopic tumour model. RESULTS Inhibition of PDI significantly enhances the cytotoxic effect of TMZ on glioblastoma cells. More importantly, inhibition of PDI is able to sensitise glioblastoma cells that are initially resistant to TMZ treatment. Nanoformulation of CCF642 is well-tolerated and effective in suppressing tumour growth. It activates cell death-triggering UPR beyond repair and induces ER perturbations through the downregulation of PERK signalling. Combination treatment of TMZ with CCF642 significantly reduces tumour growth compared with either modality alone. CONCLUSION Our study demonstrates modulation of ER stress by targeting PDI as a promising therapeutic rationale to overcome chemoresistance.
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Affiliation(s)
- Karrie Mei-Yee Kiang
- Department of Surgery, School of Clinical Medicine, LKS Faculty of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong SAR, China
| | - Wanjun Tang
- Department of Surgery, School of Clinical Medicine, LKS Faculty of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong SAR, China
| | - Qingchun Song
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong SAR, China
| | - Jiaxin Liu
- Department of Surgery, School of Clinical Medicine, LKS Faculty of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong SAR, China
| | - Ning Li
- Department of Surgery, School of Clinical Medicine, LKS Faculty of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong SAR, China
- Department of Neurosurgery, Zhongda Hospital, Southeast University, Nanjing, China
| | - Tsz-Lung Lam
- Department of Surgery, School of Clinical Medicine, LKS Faculty of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong SAR, China
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong SAR, China
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Hnog SAR, China
| | - Zhiyuan Zhu
- Department of Surgery, School of Clinical Medicine, LKS Faculty of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong SAR, China.
- Department of Functional Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou, China.
| | - Gilberto Ka-Kit Leung
- Department of Surgery, School of Clinical Medicine, LKS Faculty of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong SAR, China.
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14
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Yang S, Yu H, Xu X, Yang T, Wei Y, Zan R, Zhang X, Ma Q, Shum HC, Song Y. AIEgen-Conjugated Phase-Separating Peptides Illuminate Intracellular RNA through Coacervation-Induced Emission. ACS Nano 2023; 17:8195-8203. [PMID: 37093110 DOI: 10.1021/acsnano.2c12072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Intrinsically disordered peptides drive dynamic liquid-liquid phase separation (LLPS) in membraneless organelles and encode cellular functions in response to environmental stimuli. Engineering design on phase-separating peptides (PSPs) holds great promise for bioimaging, vaccine delivery, and disease theranostics. However, recombinant PSPs are devoid of robust luminogen or suitable cell permeability required for intracellular applications. Here, we synthesize a peptide-based RNA sensor by covalently connecting tetraphenylethylene (TPE), an aggregation-induced emission luminogen (AIEgens), to tandem peptide repeats of (RRASL)n (n = 1, 2, 3). Interestingly, the conjugation of TPE luminogen promotes liquid-liquid phase separation of the peptide repeats, and the minimum coacervation concentration (MCC) of TPE-(RRASL)n is decreased by an order of magnitude, compared to that of the untagged, TPE-free counterparts. Moreover, the luminescence of TPE-(RRASL)n is enhanced by up to 700-fold with increasing RNA concentration, which is attributed to the constricted rotation of the TPE moiety as a result of peptide/RNA coacervates within the droplet phase. Besides, at concentrations above MCC, TPE-(RRASL)n can efficiently penetrate through human gallbladder carcinoma cells (SGC-996), translocate into the cell nucleus, and colocalize with intracellular RNA. These observations suggest that AIEgen-conjugated PSPs can be used as droplet-based biosensors for intracellular RNA imaging through a regime of coacervation-induced emission.
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Affiliation(s)
- Shi Yang
- State Key Laboratory of Metal Matrix Composites, School of Material Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Han Yu
- State Key Laboratory of Metal Matrix Composites, School of Material Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Xiuli Xu
- State Key Laboratory of Metal Matrix Composites, School of Material Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Ting Yang
- State Key Laboratory of Metal Matrix Composites, School of Material Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yue Wei
- State Key Laboratory of Metal Matrix Composites, School of Material Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Rui Zan
- Shanghai Engineering Research Center of Biliary Tract Minimal Invasive Surgery and Materials, Shanghai 200032, China
| | - Xiaonong Zhang
- State Key Laboratory of Metal Matrix Composites, School of Material Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Qingming Ma
- School of Pharmacy, Qingdao University, Qingdao 266071, China
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong 999077, China
| | - Yang Song
- State Key Laboratory of Metal Matrix Composites, School of Material Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
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15
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Pan Y, Li C, Hou X, Yang Z, Li M, Shum HC. Pixelating Responsive Structural Color via a Bioinspired Morphable Concavity Array (MoCA) Composed of 2D Photonic Crystal Elastomer Actuators. Adv Sci (Weinh) 2023; 10:e2300347. [PMID: 36793100 PMCID: PMC10104634 DOI: 10.1002/advs.202300347] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Indexed: 06/18/2023]
Abstract
Stimuli-responsive structural coloration allows the color change of soft substrates in response to environmental stimuli such as heat, humidity, and solvents. Such color-changing systems enable smart soft devices, such as the camouflageable skin of soft robots or chromatic sensors in wearable devices. However, individually and independently programmable stimuli-responsive color pixels remain significant challenges among the existing color-changing soft materials and devices, which are crucial for dynamic display. Inspired by the dual-color concavities on butterfly wings, a morphable concavity array to pixelate the structural color of two-dimensional photonic crystal elastomer and achieve individually and independently addressable stimuli-responsive color pixels is designed. The morphable concavity can convert its surface between concave and flat upon changes in the solvent and temperature, accompanied by angle-dependent color-shifting. Through multichannel microfluidics, the color of each concavity can be controllably switched. Based on the system, the dynamic display by forming reversibly editable letters and patterns for anti-counterfeiting and encryption are demonstrated. It is believed that the strategy of pixelating optical properties through locally altering surface topography can inspire the design of new transformable optical devices, such as artificial compound eyes or crystalline lenses for biomimetic and robotic applications.
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Affiliation(s)
- Yi Pan
- Department of Mechanical EngineeringThe University of Hong KongPokfulam RoadHong Kong999077P. R. China
| | - Chang Li
- Department of Mechanical EngineeringThe University of Hong KongPokfulam RoadHong Kong999077P. R. China
| | - Xiaoyu Hou
- Key Laboratory of Green PrintingInstitute of ChemistryChinese Academy of SciencesBeijing100190P. R. China
| | - Zhenyu Yang
- Department of Mechanical EngineeringThe University of Hong KongPokfulam RoadHong Kong999077P. R. China
| | - Mingzhu Li
- Key Laboratory of Green PrintingInstitute of ChemistryChinese Academy of SciencesBeijing100190P. R. China
| | - Ho Cheung Shum
- Department of Mechanical EngineeringThe University of Hong KongPokfulam RoadHong Kong999077P. R. China
- Advanced Biomedical Instrumentation CentreHong Kong Science ParkNew Territories, ShatinHong Kong999077P. R. China
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16
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Cao Y, Tian J, Lin H, Li Q, Xiao Y, Cui H, Shum HC. Partitioning-Induced Isolation of Analyte and Analysis via Multiscaled Aqueous Two-Phase System. Anal Chem 2023; 95:4644-4652. [PMID: 36855862 DOI: 10.1021/acs.analchem.2c04861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Abstract
Most fluorescence-based bioanalytical applications need labeling of analytes. Conventional labeling requires washing to remove the excess fluorescent labels and reduce the noise signals. These pretreatments are labor intensive and need specialized equipment, hindering portable applications in resource-limited areas. Herein, we use the aqueous two-phase system (ATPS) to realize the partitioning-induced isolation of labeled analytes from background signals without extra processing steps. ATPS is formed by mixing two polymers at sufficiently high concentrations. ATPS-based isolation is driven by intrinsic affinity differences between analytes and excess labels. To demonstrate the partitioning-induced isolation and analysis, fluorescein isothiocyanate (FITC) is selected as the interfering fluorophore, and a monoclonal antibody (IgG) is used as the analyte. To optimize ATPS compositions, different molecular weights and mass fractions of polyethylene glycol (PEG) and dextran and different phosphate-buffered saline (PBS) concentrations are investigated. Various operational scales of our approach are demonstrated, suggesting its compatibility with various bioanalytical applications. In centimeter-scale ATPS, the optimized distribution ratios of IgG and FITC are 91.682 and 0.998 using PEG 6000 Da and dextran 10,000 Da in 10 mM PBS. In millimeter-scale ATPS, the analyte is enriched to 6.067 fold using 15 wt % PEG 35,000 Da and 5 wt % dextran 500,000 Da in 10 mM PBS. In microscale ATPS, analyte dilutions are isolated into picoliter droplets, and the measured fluorescence intensities linearly correlated with the analyte concentrations (R2 = 0.982).
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Affiliation(s)
- Yang Cao
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong SAR 999077, China
| | - Jingxuan Tian
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong SAR 999077, China
| | - Haisong Lin
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong SAR 999077, China.,Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong SAR 999077, China
| | - Qingchuan Li
- School of Chemistry and Chemical Engineering, National Engineering Research Center for Colloidal Materials, Shandong University, Jinan 250100, China.,Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong SAR 999077, China
| | - Yang Xiao
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong SAR 999077, China
| | - Huanqing Cui
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong SAR 999077, China
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong SAR 999077, China.,Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong SAR 999077, China
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17
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Nan L, Mao T, Shum HC. Self-synchronization of reinjected droplets for high-efficiency droplet pairing and merging. Microsyst Nanoeng 2023; 9:24. [PMID: 36910256 PMCID: PMC9995457 DOI: 10.1038/s41378-023-00502-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 01/10/2023] [Accepted: 01/31/2023] [Indexed: 06/18/2023]
Abstract
Droplet merging serves as a powerful tool to add reagents to moving droplets for biological and chemical reactions. However, unsynchronized droplet pairing impedes high-efficiency merging. Here, we develop a microfluidic design for the self-synchronization of reinjected droplets. A periodic increase in the hydrodynamic resistance caused by droplet blocking a T-junction enables automatic pairing of droplets. After inducing spacing, the paired droplets merge downstream under an electric field. The blockage-based design can achieve a 100% synchronization efficiency even when the mismatch rate of droplet frequencies reaches 10%. Over 98% of the droplets can still be synchronized at nonuniform droplet sizes and fluctuating reinjection flow rates. Moreover, the droplet pairing ratio can be adjusted flexibly for on-demand sample addition. Using this system, we merge two groups of droplets encapsulating enzyme/substrate, demonstrating its capacity to conduct multi-step reactions. We also combine droplet sorting and merging to coencapsulate single cells and single beads, providing a basis for high-efficiency single-cell sequencing. We expect that this system can be integrated with other droplet manipulation systems for a broad range of chemical and biological applications.
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Affiliation(s)
- Lang Nan
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong China
| | - Tianjiao Mao
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Ho Cheung Shum
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong China
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
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18
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Wang F, Li C, Zhang R, Liu Y, Lin H, Nan L, Khan MA, Xiao Y, Shum HC, Deng H. A composition-tunable cold atmospheric plasma chip for multiplex-treatment of cells. Lab Chip 2023; 23:580-590. [PMID: 36644992 DOI: 10.1039/d2lc00951j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Cold atmospheric plasma treatment promises a targeted cancer therapy due to its selectivity and specificity in killing tumor cells. However, the current plasma exposure devices produce diverse and coupled reactive species, impeding the investigation of the underlying plasma-anticancer mechanisms. Also, the limited mono-sample and mono-dosage treatment modality result in tedious and manual experimental tasks. Here, we propose a cold atmospheric plasma chip producing targeted species, delivering multiple dosages, and treating multiple cell lines in a single treatment. Three modules are integrated into the chip. The environment control module and multi-inlet gas-feed module coordinately ignite component-tunable and uniformly distributed plasma. The multi-sample holding module enables multiplex treatment: multi-sample and -dosage treatment with single radiation. By exposing the HepG2 cell line to nitrogen-feed plasmas, we prove the crucial role of nitrogen-based species in inhibiting cell growth and stimulating apoptosis. By loading four-type cell lines on our chip, we can identify the most vulnerable cell line for plasma oncotherapy. Simultaneously, three-level treatment dosages are imposed on the cells with single radiation to optimize the applicable treatment dosage for plasma oncotherapy. Our chip will broaden the design principles of plasma exposure devices, potentially help clarify plasma-induced anticancer mechanisms, and guide the clinical application of plasma-based oncotherapy.
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Affiliation(s)
- Fang Wang
- Department of Mechanical and Energy Engineering, Southern University of Science and Technology, No. 1088, Xueyuan Road, Shenzhen, Guangdong, China.
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China.
| | - Chang Li
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China.
| | - Ruotong Zhang
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China.
| | - Yuan Liu
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China.
| | - Haisong Lin
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China.
| | - Lang Nan
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China.
| | - Muhammad Ajmal Khan
- Department of Mechanical and Energy Engineering, Southern University of Science and Technology, No. 1088, Xueyuan Road, Shenzhen, Guangdong, China.
| | - Yang Xiao
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China.
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China.
| | - Hui Deng
- Department of Mechanical and Energy Engineering, Southern University of Science and Technology, No. 1088, Xueyuan Road, Shenzhen, Guangdong, China.
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19
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Hou Y, Yuan S, Zhu G, You B, Xu Y, Jiang W, Shum HC, Pong PWT, Chen CH, Wang L. Photonic Crystal-Integrated Optoelectronic Devices with Naked-Eye Visualization and Digital Readout for High-Resolution Detection of Ultratrace Analytes. Adv Mater 2023; 35:e2209004. [PMID: 36478473 DOI: 10.1002/adma.202209004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 11/14/2022] [Indexed: 06/17/2023]
Abstract
The detection of ultratrace analytes is highly desirable for the non-invasive monitoring of human diseases. However, a major challenge is fast, naked-eye, high-resolution ultratrace detection. Herein, a rectangular 3D composite photonic crystal (PC)-based optoelectronic device is first designed that combines the sensitivity-enhancing effects of PCs and optoelectronic devices with fast and real-time digital monitoring. A crack-free, centimeter-scale, mechanically robust ellipsoidal composite PCs with sufficient hardness and modulus, even exceeding most plastics and aluminum alloys, are developed. The high mechanical strength of ellipsoidal composite PCs allows them to be hand-machined into rectangular geometries that can be conformally covered with the centimeter-scale flat light-detection area without interference from ambient light, easily integrating 3D composite PC-based optoelectronic devices. The PC-based device's signal-to-noise ratio increases dramatically from original 30-40 to ≈60-70 dB. Droplets of ultratrace analytes on the device are identified by fast digital readout within seconds, with detection limits down to 5 µL, enabling rapid identification of ultratrace glucose in artificial sweat and diabetes risk. The developed 3D PC-based sensor offers the advantages of small size, low cost, and high reliability, paving the way for wider implementation in other portable optoelectronic devices.
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Affiliation(s)
- Yi Hou
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong, 999077, P. R. China
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, 999077, P. R. China
| | - Shuai Yuan
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong, 999077, P. R. China
| | - Guangda Zhu
- Center for Advanced Materials (CAM), Heidelberg University, 69120, Heidelberg, Germany
| | - Baihao You
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong, 999077, P. R. China
| | - Ying Xu
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong, 999077, P. R. China
| | - Wenxin Jiang
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong, 999077, P. R. China
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, 999077, P. R. China
| | - Philip W T Pong
- Department of Electrical and Computer Engineering, New Jersey Institute of Technology, Newark, NJ, 07102, USA
| | - Chia-Hung Chen
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong, 999077, P. R. China
| | - Liqiu Wang
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, 999077, P. R. China
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20
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Guo W, Ji D, Kinghorn AB, Chen F, Pan Y, Li X, Li Q, Huck WTS, Kwok CK, Shum HC. Tuning Material States and Functionalities of G-Quadruplex-Modulated RNA-Peptide Condensates. J Am Chem Soc 2023; 145:2375-2385. [PMID: 36689740 DOI: 10.1021/jacs.2c11362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
RNA encodes sequence- and structure-dependent interactions to modulate the assembly and properties of biomolecular condensates. RNA G-quadruplexes (rG4s) formed by guanine-rich sequences can trigger the formation of liquid- or solid-like condensates that are involved in many aberrant phase transitions. However, exactly how rG4 motifs modulate different phase transitions and impart distinct material properties to condensates is unclear. Here, using RNA oligonucleotides and cationic peptides as model systems, we show that RNA-peptide condensates exhibit tunability in material properties over a wide spectrum via interactions arising from rG4 folding/unfolding kinetics. rG4-containing oligonucleotides formed strong pairwise attraction with peptides and tended to form solid-like condensates, while their less-structured non-G4 mutants formed liquid-like droplets. We find that the coupling between rG4 dissociation and RNA-peptide complex coacervation triggers solid-to-liquid transition of condensates prior to the complete unfolding of rG4s. This coupling points to a mechanism that material states of rG4-modulated condensates can be finely tuned from solid-like to liquid-like by the addition of less-structured RNA oligonucleotides, which have weak but dominant binding with peptides. We further show that the tunable material states of condensates can enhance RNA aptamer compartmentalization and RNA cleavage reactions. Our results suggest that condensates with complex properties can emerge from subtle changes in RNA oligonucleotides, contributing ways to treat dysfunctional condensates in diseases and insights into prebiotic compartmentalization.
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Affiliation(s)
- Wei Guo
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Hong Kong 999077, China.,Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong 999077,China
| | - Danyang Ji
- Department of Chemistry and State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong 999077, China
| | - Andrew B Kinghorn
- School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong 999077, China
| | - Feipeng Chen
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Hong Kong 999077, China
| | - Yi Pan
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Hong Kong 999077, China
| | - Xiufeng Li
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong 999077,China
| | - Qingchuan Li
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong 999077,China
| | - Wilhelm T S Huck
- Institute for Molecules and Materials, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, Netherlands
| | - Chun Kit Kwok
- Department of Chemistry and State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong 999077, China.,Shenzhen Research Institute of City University of Hong Kong, Shenzhen 518057, China
| | - Ho Cheung Shum
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Hong Kong 999077, China.,Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong 999077,China
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21
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Wang Y, Li X, Li T, Wang Y, Jiang J, Zhang X, Huang J, Xia B, Shum HC, Yang Z, Dong W. Ultra-stable pickering emulsions stabilized by zein-cellulose conjugate particles with tunable interfacial affinity. Food Hydrocoll 2023. [DOI: 10.1016/j.foodhyd.2022.108055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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22
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Cui H, Zhang Y, Shen Y, Zhu S, Tian J, Li Q, Shen Y, Liu S, Cao Y, Shum HC. Dynamic Assembly of Viscoelastic Networks by Aqueous Liquid-Liquid Phase Separation and Liquid-Solid Phase Separation (AqLL-LS PS 2 ). Adv Mater 2022; 34:e2205649. [PMID: 36222390 DOI: 10.1002/adma.202205649] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 09/19/2022] [Indexed: 06/16/2023]
Abstract
Living cells comprise diverse subcellular structures, such as cytoskeletal networks, which can regulate essential cellular activities through dynamic assembly and synergistic interactions with biomolecular condensates. Despite extensive efforts, reproducing viscoelastic networks for modulating biomolecular condensates in synthetic systems remains challenging. Here, a new aqueous two-phase system (ATPS) is proposed, which consists of poly(N-isopropylacrylamide) (PNIPAM) and dextran (DEX), to construct viscoelastic networks capable of being assembled and dissociated dynamically to regulate the self-assembly of condensates on-demand. Viscoelastic networks are generated using liquid-liquid phase-separated DEX droplets as templates and the following liquid-to-solid transition of the PNIPAM-rich phase. The resulting networks can dissolve liquid fused in sarcoma (FUS) condensates within 5 min. This work demonstrates rich phase-separation behaviors in a single ATPS through incorporating stimuli-responsive polymers. The concept can potentially be applied to other macromolecules through other stimuli to develop materials with rich phase behaviors and hierarchical structures.
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Affiliation(s)
- Huanqing Cui
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
- The University of Hong Kong-Shenzhen Institute for Research and Innovation (HKU-SIRI), Shenzhen, 518000, China
| | - Yage Zhang
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
- The Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong (SAR), China
| | - Yinan Shen
- Department of Physics, Harvard University, Cambridge, MA, 02138, USA
| | - Shipei Zhu
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
- The University of Hong Kong-Shenzhen Institute for Research and Innovation (HKU-SIRI), Shenzhen, 518000, China
| | - Jingxuan Tian
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
- The Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong (SAR), China
| | - Qingchuan Li
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
- School of Chemistry & Chemical Engineering, National Engineering Research Center for Colloidal Materials, Shandong University, Jinan, 250100, China
| | - Yi Shen
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, NSW, 2006, Australia
- The University of Sydney Nano Institute, The University of Sydney, Sydney, NSW, 2006, Australia
| | - Sihan Liu
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
- The University of Hong Kong-Shenzhen Institute for Research and Innovation (HKU-SIRI), Shenzhen, 518000, China
| | - Yang Cao
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
- The University of Hong Kong-Shenzhen Institute for Research and Innovation (HKU-SIRI), Shenzhen, 518000, China
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
- The University of Hong Kong-Shenzhen Institute for Research and Innovation (HKU-SIRI), Shenzhen, 518000, China
- The Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong (SAR), China
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23
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Zhu S, Xie G, Cui H, Li Q, Forth J, Yuan S, Tian J, Pan Y, Guo W, Chai Y, Zhang Y, Yang Z, Yu RWH, Yu Y, Liu S, Chao Y, Shen Y, Zhao S, Russell TP, Shum HC. Aquabots. ACS Nano 2022; 16:13761-13770. [PMID: 35904791 DOI: 10.1021/acsnano.2c00619] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Soft robots, made from elastomers, easily bend and flex, but deformability constraints severely limit navigation through and within narrow, confined spaces. Using aqueous two-phase systems we print water-in-water constructs that, by aqueous phase-separation-induced self-assembly, produce ultrasoft liquid robots, termed aquabots, comprised of hierarchical structures that span in length scale from the nanoscopic to microsciopic, that are beyond the resolution limits of printing and overcome the deformability barrier. The exterior of the compartmentalized membranes is easily functionalized, for example, by binding enzymes, catalytic nanoparticles, and magnetic nanoparticles that impart sensitive magnetic responsiveness. These ultrasoft aquabots can adapt their shape for gripping and transporting objects and can be used for targeted photocatalysis, delivery, and release in confined and tortuous spaces. These biocompatible, multicompartmental, and multifunctional aquabots can be readily applied to medical micromanipulation, targeted cargo delivery, tissue engineering, and biomimetics.
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Affiliation(s)
- Shipei Zhu
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong 999077, (SAR), Hong Kong, P. R. China
| | - Ganhua Xie
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley 94720, California, United States
- College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, P. R. China
| | - Huanqing Cui
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong 999077, (SAR), Hong Kong, P. R. China
| | - Qingchuan Li
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong 999077, (SAR), Hong Kong, P. R. China
- School of Chemistry & Chemical Engineering, National Engineering Research Center for Colloidal Materials, Shandong University, Jinan 250100, P. R. China
| | - Joe Forth
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley 94720, California, United States
- Department of Chemistry, University College London, London WC1H 0AJ, United Kingdom
| | - Shuai Yuan
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong 999077, (SAR), Hong Kong, P. R. China
| | - Jingxuan Tian
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong 999077, (SAR), Hong Kong, P. R. China
| | - Yi Pan
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong 999077, (SAR), Hong Kong, P. R. China
| | - Wei Guo
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong 999077, (SAR), Hong Kong, P. R. China
| | - Yu Chai
- Department of Physics, The City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong 999077, P. R. China
| | - Yage Zhang
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong 999077, (SAR), Hong Kong, P. R. China
| | - Zhenyu Yang
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong 999077, (SAR), Hong Kong, P. R. China
| | - Ryan Wing Hei Yu
- Department of Engineering, University of Cambridge, Trumpington Street, Cambridge CB2 1PZ, U.K
| | - Yafeng Yu
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong 999077, (SAR), Hong Kong, P. R. China
| | - Sihan Liu
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong 999077, (SAR), Hong Kong, P. R. China
- Department of Electrical and Electronics Engineering, Southern University of Science and Technology, Shenzhen 518055, P. R. China
| | - Youchuang Chao
- Max Planck Institute for Dynamics and Self-Organization, Göttingen 37077, Germany
| | - Yinan Shen
- Department of Physics, Harvard University, Cambridge 02138, Massachusetts, United States
| | - Sai Zhao
- Department of Physics, The City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong 999077, P. R. China
| | - Thomas P Russell
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley 94720, California, United States
- Polymer Science and Engineering Department, University of Massachusetts, Amherst 01003, Massachusetts, United States
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, P. R. China
- WPI-Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong 999077, (SAR), Hong Kong, P. R. China
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong 999077, (SAR), Hong Kong, P. R. China
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24
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Yuan S, Zhang Y, Nan L, Lai PT, Zhang T, Pong PWT, Shum HC. High-Throughput Generation, Manipulation, and Degradation of Magnetic Nanoparticleladen Alginate Core-shell Beads for Single Bacteria Culturing Analysis. IEEE Trans Nanobioscience 2022; PP. [PMID: 36074887 DOI: 10.1109/tnb.2022.3205057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Microbes could be found almost everywhere around us and have significant impacts on our human society. The treatment of microorganisms has long been seen as a complex problem. Till now, most of the genetic and phenotypic information regarding rare species is buried in the bulk microbial colony due to a lack of efficient tools to screen live bacteria. Droplet microfluidics offers a powerful approach to address this problem. However, the interactions among bacteria and their living environment are entirely restricted by the water/oil interfaces in conventional water/oil single emulsion-based microfluidic systems. Here, we demonstrate an oil-mediated all-aqueous microfluidic workflow that can overcome this drawback. In contrast to the previous works, our all-aqueous culturing environment allows cell-cell and cell-environment interactions, thus facilitating the growth of bacteria. Fe3O4 magnetic nanoparticles added into the alginate beads enables on-chip manipulation of the microcapsules. The core-shell structure separately encapsulates bacteria and magnetic particles in the core and shell to avoid contamination. We demonstrate the feasibility of this approach by single bacterium culturing in droplet-templated alginate beads. Finally, a new approach is proposed to degrade the alginate beads for post-treatment. This novel microfluidic workflow can create new opportunities for microbial applications, such as bacteria culturing and screening.
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25
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Zhang Y, Cui H, Binks BP, Shum HC. Liquid Marbles under Electric Fields: New Capabilities for Non-wetting Droplet Manipulation and Beyond. Langmuir 2022; 38:9721-9740. [PMID: 35918302 DOI: 10.1021/acs.langmuir.2c01127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The study of liquid marbles (LMs) composed of stabilizing liquid droplets with solid particles in a gaseous environment has matured into an established area in surface and colloid science. The minimized "solid-liquid-air" triphase interface enables LMs to drastically reduce adhesion to a solid substrate, making them unique non-wetting droplets transportable with limited energy. The small volume, enclosed environment, and simple preparation render them suitable microreactors in industrial applications and processes such as cell culture, material synthesis, and blood coagulation. Extensive application contexts request precise and highly efficient manipulations of these non-wetting droplets. Many external fields, including magnetic, acoustic, photothermal, and pH, have emerged to prepare, deform, actuate, coalesce, mix, and disrupt these non-wetting droplets. Electric fields are rising among these external stimuli as an efficient source for manipulating the LMs with high controllability and a significant ability to contribute further to proposed applications. This Feature Article attempts to outline the recent developments related to LMs with the aid of electric fields. The effects of electric fields on the preparation and manipulation of LMs with intricate interfacial processes are discussed in detail. We highlight a wealth of novel electric field-involved LM-based applications and beyond while also envisaging the challenges, opportunities, and new directions for future development in this emerging research area.
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Affiliation(s)
- Yage Zhang
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam 999077, Hong Kong, China
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin 999077, Hong Kong, China
| | - Huanqing Cui
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam 999077, Hong Kong, China
| | - Bernard P Binks
- Department of Chemistry, University of Hull, Hull HU6 7RX, United Kingdom
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam 999077, Hong Kong, China
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin 999077, Hong Kong, China
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26
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Li X, You B, Shum HC, Chen CH. Future foods: Design, fabrication and production through microfluidics. Biomaterials 2022; 287:121631. [PMID: 35717791 DOI: 10.1016/j.biomaterials.2022.121631] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 05/12/2022] [Accepted: 06/09/2022] [Indexed: 11/02/2022]
Abstract
Many delicious foods are soft matter systems with health ingredients and unique internal structures that provide rich nutrition, unique textures, and popular flavors. Obtaining these special properties in food products usually requires specialized processes. Microfluidic technologies have been developed to physically manipulate liquids to produce a broad range of microunits, providing a suitable approach for precise fabrication of functional biomaterials with desirable interior structures in a bottom-up fashion. In this review, we present how microfluidics has been applied to produce gel-based structures and highlight their use in fabricating novel foods, focusing on, among others, cultured meat as a rapidly growing field in food industry. We first discuss the behaviors of food liquids in microchannels for fluidic structure design. Then, different types of microsized building blocks with specific geometries fabricated through microfluidics are introduced, including particles (point), fibers (line), and sheets (plane). These well-defined units can encapsulate or interact with cells, forming microtissues to construct meat products with desirable architectures. After that, we review approaches to scale up microfluidic devices for mass production of the hydrogel building blocks and highlight the challenges associated with bottom-up food production.
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Affiliation(s)
- Xiufeng Li
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong, China
| | - Baihao You
- Department of Biomedical Engineering, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon Tong, Hong Kong, China
| | - Ho Cheung Shum
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong, China; Department of Mechanical Engineering, University of Hong Kong, Pokfulam Road, Hong Kong, China.
| | - Chia-Hung Chen
- Department of Biomedical Engineering, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon Tong, Hong Kong, China; City University of Hong Kong, Shenzhen Research Institute, 8 Yuexing 1st Road, Shenzhen Hi-tech Industrial Park, Nanshan District, Shenzhen, China.
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27
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Li C, Yu Y, Li H, Tian J, Guo W, Shen Y, Cui H, Pan Y, Song Y, Shum HC. One-Pot Self-Assembly of Dual-Color Domes Using Mono-Sized Silica Nanoparticles. Nano Lett 2022; 22:5236-5243. [PMID: 35731830 DOI: 10.1021/acs.nanolett.2c01090] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Spots with dual structural colors on the skin of some organisms in nature are of tremendous interest due to the unique function of their dye-free colors. However, imitation of them requires complicated manufacturing processes, expensive equipment, and multiple predesigned building blocks. In this work, a one-pot strategy based on the phase-separation-assisted nonuniform self-assembly of monosized silica nanoparticles is developed to construct domes with dual structural colors. In drying poly(ethylene glycol)-dextran-based (PEG-DEX) droplets, monosized nanoparticles distribute nonuniformly in two compartments due to the droplet inner flow and different nanoparticle compatibility with the two phases. The dome colors are derived from the self-assembled nanoparticles and are programmable by regulating the assembly conditions. The one-pot strategy enables the preparation of multicolor using only one type of building block. With the dual-color domes, encrypted patterns with a high volume of contents are designed, showing promising applications in information delivery.
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Affiliation(s)
- Chang Li
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong (SAR), China
| | - Yafeng Yu
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong (SAR), China
| | - Huizeng Li
- Key Laboratory of Green Printing, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Jingxuan Tian
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong (SAR), China
| | - Wei Guo
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong (SAR), China
| | - Yanting Shen
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong (SAR), China
| | - Huanqing Cui
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong (SAR), China
| | - Yi Pan
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong (SAR), China
| | - Yanlin Song
- Key Laboratory of Green Printing, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Ho Cheung Shum
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong (SAR), China
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong (SAR), China
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28
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Zhao S, Zhang JY, Fu Y, Zhu S, Shum HC, Liu X, Wang Z, Ye R, Tang BZ, Russell TP, Chai Y. Shape-Reconfigurable Ferrofluids. Nano Lett 2022; 22:5538-5543. [PMID: 35766622 DOI: 10.1021/acs.nanolett.2c01721] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Ferrofluids (FFs) can adapt their shape to a magnetic field. However, they cannot maintain their shape when the magnetic field is removed. Here, with a magneto-responsive and reconfigurable interfacial self-assembly (MRRIS) process, we show that FFs can be structured by a magnetic field and maintain their shape, like solids, after removing the magnetic field. The competing self-assembly of magnetic and nonmagnetic nanoparticles at the liquid interface endow FFs with both reconfigurability and structural stability. By manipulating the external magnetic field, we show that it is possible to "write" and "erase" the shape of the FFs remotely and repeatedly. To gain an in-depth understanding of the effect of MRRIS on the structure of FFs, we systematically study the shape variation of these liquids under both the static and dynamic magnetic fields. Our study provides a simple yet novel way of manipulating FFs and opens opportunities for the fabrication of all-liquid devices.
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Affiliation(s)
- Sai Zhao
- Department of Physics, The City University of Hong Kong; 83 Tat Chee Avenue, Kowloon, Hong Kong SAR 999077, China
| | - Jun-Yan Zhang
- Department of Physics, The City University of Hong Kong; 83 Tat Chee Avenue, Kowloon, Hong Kong SAR 999077, China
| | - Yuchen Fu
- Department of Physics, The City University of Hong Kong; 83 Tat Chee Avenue, Kowloon, Hong Kong SAR 999077, China
| | - Shipei Zhu
- Department of Mechanical Engineering, The University of Hong Kong; Hong Kong (SAR), Hong Kong SAR 999077, China
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong; Hong Kong (SAR), Hong Kong SAR 999077, China
| | - Xubo Liu
- CAS Key Laboratory of Bio-Inspired Materials and Interfacial Science, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Zhaoyu Wang
- Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction and Institute for Advanced Study. The Hong Kong University of Science and Technology Clear Water Bay, Kowloon, Hong Kong SAR 999077, China
| | - Ruquan Ye
- Department of Chemistry, State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong SAR 999077, China
| | - Ben Zhong Tang
- School of Science and Engineering, Shenzhen Institute of Aggregate Science and Technology, The Chinese University of Hong Kong, Shenzhen, Guangdong 518172, China
| | - Thomas P Russell
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Polymer Science and Engineering Department, University of Massachusetts; Amherst, Massachusetts 01003, United States
- Advanced Institute for Materials Research (AIMR), Tohoku University; Sendai 980-8577, Japan
| | - Yu Chai
- Department of Physics, The City University of Hong Kong; 83 Tat Chee Avenue, Kowloon, Hong Kong SAR 999077, China
- City University of Hong Kong Shenzhen Research Institute, 8 Yuexing first Road, Gaoxin District, Shenzhen 518057, China
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29
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Wang M, Lee KCM, Chung BMF, Bogaraju SV, Ng HC, Wong JSJ, Shum HC, Tsia KK, So HKH. Low-Latency In Situ Image Analytics With FPGA-Based Quantized Convolutional Neural Network. IEEE Trans Neural Netw Learn Syst 2022; 33:2853-2866. [PMID: 33434136 DOI: 10.1109/tnnls.2020.3046452] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Real-time in situ image analytics impose stringent latency requirements on intelligent neural network inference operations. While conventional software-based implementations on the graphic processing unit (GPU)-accelerated platforms are flexible and have achieved very high inference throughput, they are not suitable for latency-sensitive applications where real-time feedback is needed. Here, we demonstrate that high-performance reconfigurable computing platforms based on field-programmable gate array (FPGA) processing can successfully bridge the gap between low-level hardware processing and high-level intelligent image analytics algorithm deployment within a unified system. The proposed design performs inference operations on a stream of individual images as they are produced and has a deeply pipelined hardware design that allows all layers of a quantized convolutional neural network (QCNN) to compute concurrently with partial image inputs. Using the case of label-free classification of human peripheral blood mononuclear cell (PBMC) subtypes as a proof-of-concept illustration, our system achieves an ultralow classification latency of 34.2 [Formula: see text] with over 95% end-to-end accuracy by using a QCNN, while the cells are imaged at throughput exceeding 29 200 cells/s. Our QCNN design is modular and is readily adaptable to other QCNNs with different latency and resource requirements.
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30
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Hung LT, Poon SHL, Yan WH, Lace R, Zhou L, Wong JKW, Williams RL, Shih KC, Shum HC, Chan YK. Scaffold-Free Strategy Using a PEG-Dextran Aqueous Two-Phase-System for Corneal Tissue Repair. ACS Biomater Sci Eng 2022; 8:1987-1999. [PMID: 35362956 DOI: 10.1021/acsbiomaterials.1c01500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Forming thin tissue constructs with minimal extracellular matrix surrounding them is important for tissue engineering applications. Here, we explore and optimize a strategy that enables rapid fabrication of scaffold-free corneal tissue constructs using the liquid-liquid interface of an aqueous two-phase system (ATPS) that is based on biocompatible polymers, dextran and polyethylene glycol. Intact tissue-like constructs, made of corneal epithelial or endothelial cells, can be formed on the interface between the two liquid phases of ATPS within hours and subsequently collected simply by removing the liquid phases. The formed corneal cell constructs express essential physiological markers and have preserved viability and proliferative ability in vitro. The corneal epithelial cell constructs are also able to re-epithelialize the corneal epithelial wound in vitro. The results suggest the promise of our reported strategy in corneal repair.
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Affiliation(s)
- Lap Tak Hung
- Department of Mechanical Engineering, Faculty of Engineering, University of Hong Kong, Rm 7-25, Haking Wong Building, Pokfulam Road, Hong Kong SAR 999077, China
| | - Stephanie Hiu Ling Poon
- Department of Ophthalmology, Li Ka Shing Faculty of Medicine, University of Hong Kong, 301B Cyberport 4, 100 Cyberport Road, Pokfulam, Hong Kong SAR 999077, China
| | - Wing Huen Yan
- Department of Ophthalmology, Li Ka Shing Faculty of Medicine, University of Hong Kong, 301B Cyberport 4, 100 Cyberport Road, Pokfulam, Hong Kong SAR 999077, China
| | - Rebecca Lace
- Department of Eye and Vision Sciences, Institute of Life Course and Medical Sciences, University of Liverpool, William Henry Duncan Building, 6 West Derby Street, Liverpool L7 8TX, U.K
| | - Liangyu Zhou
- Department of Ophthalmology, Li Ka Shing Faculty of Medicine, University of Hong Kong, 301B Cyberport 4, 100 Cyberport Road, Pokfulam, Hong Kong SAR 999077, China
| | - Jasper Ka Wai Wong
- Department of Ophthalmology, Li Ka Shing Faculty of Medicine, University of Hong Kong, 301B Cyberport 4, 100 Cyberport Road, Pokfulam, Hong Kong SAR 999077, China
| | - Rachel L Williams
- Department of Eye and Vision Sciences, Institute of Life Course and Medical Sciences, University of Liverpool, William Henry Duncan Building, 6 West Derby Street, Liverpool L7 8TX, U.K
| | - Kendrick Co Shih
- Department of Ophthalmology, Li Ka Shing Faculty of Medicine, University of Hong Kong, 301B Cyberport 4, 100 Cyberport Road, Pokfulam, Hong Kong SAR 999077, China
| | - Ho Cheung Shum
- Department of Mechanical Engineering, Faculty of Engineering, University of Hong Kong, Rm 7-25, Haking Wong Building, Pokfulam Road, Hong Kong SAR 999077, China
| | - Yau Kei Chan
- Department of Ophthalmology, Li Ka Shing Faculty of Medicine, University of Hong Kong, 301B Cyberport 4, 100 Cyberport Road, Pokfulam, Hong Kong SAR 999077, China
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31
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Abstract
The healthy functioning of the plants' vasculature depends on their ability to respond to environmental changes. In contrast, synthetic microfluidic systems have rarely demonstrated this environmental responsiveness. Plants respond to environmental stimuli through nastic movement, which inspires us to introduce transformable microfluidics: By embedding stimuli-responsive materials, the microfluidic device can respond to temperature, humidity, and light irradiance. Furthermore, by designing a foldable geometry, these responsive movements can follow the preset origami transformation. We term this device TransfOrigami microfluidics (TOM) to highlight the close connection between its transformation and the origami structure. TOM can be used as an environmentally adaptive photomicroreactor. It senses the environmental stimuli and feeds them back positively into photosynthetic conversion through morphological transformation. The principle behind this morphable microsystem can potentially be extended to applications that require responsiveness between the environment and the devices, such as dynamic artificial vascular networks and shape-adaptive flexible electronics.
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Affiliation(s)
- Yi Pan
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China
| | - Zhenyu Yang
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China
| | - Chang Li
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China
| | - Sammer Ul Hassan
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China
- Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong SAR, China
- Corresponding author.
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Fan N, Zhao J, Zhao W, Zhang X, Song Q, Shen Y, Shum HC, Wang Y, Rong J. Celastrol-loaded lactosylated albumin nanoparticles attenuate hepatic steatosis in non-alcoholic fatty liver disease. J Control Release 2022; 347:44-54. [PMID: 35483638 DOI: 10.1016/j.jconrel.2022.04.034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 04/04/2022] [Accepted: 04/21/2022] [Indexed: 12/18/2022]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is a multifactorial disease with several liver-associated pathologic characteristics such as aberrant lipid accumulation, persistent chronic inflammation and hyperactive endoplasmic reticulum (ER) stress. Plant-derived celastrol (CEL) appeared to be a promising anti-inflammatory and anti-obesity drug but the clinical application was delayed by low oral bioavailability. The present study was designed for developing biodegradable albumin-based nanoparticles to deliver CEL to the liver for treating NAFLD. CEL was entrapped into lactosylated bovine serum albumin (Lac-BSA) by high pressure homogenization to generate CEL-loaded Lac-BSA nanoparticles (CEL-Lac-BSA). CEL-Lac-BSA displayed spherical morphology, narrow size distribution at 158.6 ± 3.4 nm and reasonable drug-loading efficiency at 13.62 ± 0.13%. CEL-Lac-BSA not only showed better hepatocyte uptake and hepatic deposition than free CEL, but also outperformed in reducing lipid deposition, ameliorating liver function and enhancing insulin sensitivity in a mouse model of diet-induced NAFLD. Mechanistic studies indicated that CEL-Lac-BSA more effectively downregulated the mRNA levels of genes for lipogenesis and lipid transporter while upregulated the mRNA levels of lipolysis mediators. Western blot analysis confirmed the outperformance of CEL-Lac-BSA in enhancing the activation of AMP-activated protein kinase (AMPK) and silent information regulation 2 homolog (SIRT1) and the protein levels of fatty acid synthase (FASN) and sterol regulatory element-binding protein-1c (SREBP1c) in NAFLD mice. Taken together, CEL-Lac-BSA showed better potential in the treatment of diet-induced NAFLD. Lactose-coating of albumin-based nanoparticles effectively facilitated the liver-targeting release of hydrophobic drug CEL for ameliorating hepatic steatosis. Therefore, CEL-Lac-BSA may be translated into a potential clinical therapy against obesity and NAFLD.
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Affiliation(s)
- Ni Fan
- School of Chinese Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Jia Zhao
- School of Chinese Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Wei Zhao
- School of Chinese Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Xiuying Zhang
- School of Chinese Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Qingchun Song
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China
| | - Yanting Shen
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China
| | - Yu Wang
- Department of Pharmacology and Pharmacy, The University of Hong Kong, Hong Kong, China
| | - Jianhui Rong
- School of Chinese Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China; Shenzhen Institute of Research and Innovation, The University of Hong Kong, Shenzhen, China.
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Zhang Y, Yang C, Yuan S, Yao X, Chao Y, Cao Y, Song Q, Sauret A, Binks BP, Shum HC. Effects of particle size on the electrocoalescence dynamics and arrested morphology of liquid marbles. J Colloid Interface Sci 2022; 608:1094-1104. [PMID: 34879587 DOI: 10.1016/j.jcis.2021.09.187] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 09/28/2021] [Accepted: 09/28/2021] [Indexed: 12/26/2022]
Abstract
HYPOTHESIS The coalescence of bare droplets when surface tension dominates always results in one larger spherical droplet. In contrast, droplets coated with particles may be stabilized into non-spherical structures after arrested coalescence, which can be achieved by different approaches, such as changing the particle surface coverage. The size of particles coating the initial liquid marbles can be used to control the coalescence dynamics and the resulting morphology of arrested droplets. EXPERIMENT We characterized the electrocoalescence of liquid marbles coated with particles ranging from hundred nanometers to hundred micrometers. The electrocoalescence was recorded using high-speed imaging. FINDINGS When the electrocoalescence initiates, particles jam and halt the relaxation of the marbles at different stages, resulting in four possible final morphologies that are characterized using the Gaussian curvature at the neck region. The four regimes are total coalescence, arrested puddle coalescence, arrested saddle coalescence, and non-coalescence. The coalescence is initiated at the center of the contact zone, independent of the particle size. Small particles show little resistance to the coalescence, while marbles coated by large particles demonstrate a viscous-like behavior, indicated by the growth of the liquid bridge and the damping. The present study provides guidelines for applications that involve the formulation of liquid marbles with complex morphologies.
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Affiliation(s)
- Yage Zhang
- Department of Mechanical Engineering, University of Hong Kong, Pokfulam Road, Hong Kong, China.
| | - Chentianyi Yang
- Department of Mechanical Engineering, University of Hong Kong, Pokfulam Road, Hong Kong, China.
| | - Shuai Yuan
- Department of Mechanical Engineering, University of Hong Kong, Pokfulam Road, Hong Kong, China.
| | - Xiaoxue Yao
- Department of Biomedical Engineering, Shenzhen University, Shenzhen 518000, China.
| | - Youchuang Chao
- Department of Mechanical Engineering, University of Hong Kong, Pokfulam Road, Hong Kong, China.
| | - Yang Cao
- Department of Mechanical Engineering, University of Hong Kong, Pokfulam Road, Hong Kong, China.
| | - Qingchun Song
- Department of Mechanical Engineering, University of Hong Kong, Pokfulam Road, Hong Kong, China.
| | - Alban Sauret
- Department of Mechanical Engineering, University of California, Santa Barbara, CA 93106, USA.
| | - Bernard P Binks
- Department of Chemistry, University of Hull, Hull HU6 7RX, UK.
| | - Ho Cheung Shum
- Department of Mechanical Engineering, University of Hong Kong, Pokfulam Road, Hong Kong, China.
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Fan N, Zhao J, Zhao W, Shen Y, Song Q, Shum HC, Wang Y, Rong J. Biodegradable celastrol-loaded albumin nanoparticles ameliorate inflammation and lipid accumulation in diet-induced obese mice. Biomater Sci 2022; 10:984-996. [PMID: 35019905 DOI: 10.1039/d1bm01637g] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Obesity is hallmarked by endoplasmic reticulum (ER) stress, chronic inflammation and metabolic dysfunctions. The control of obesity is the key to preventing the onset of non-alcoholic fatty liver disease, diabetes, cerebro-cardiovascular diseases and cancers. As a promising anti-obesity drug, plant-derived celastrol is challenged by poor water solubility and low oral bioavailability in clinical applications. The present study was designed to develop a biocompatible albumin-based nanoparticle carrier system for the controlled release of celastrol in diet-induced obese mice. Celastrol was loaded into bovine serum albumin (BSA) nanoparticles to yield celastrol-BSA-NPs by high pressure homogenization. Celastrol-BSA-NPs exhibited spherical morphology, narrow size distribution with a diameter of 125.6 ± 2.2 nm, satisfactory drug-loading efficiency at 13.88 ± 0.12% and a sustained-release profile over a period of 168 h. Compared with free celastrol, celastrol-BSA-NPs effectively improved cellular uptake, intestinal absorption and hepatic deposition. In animal experiments, celastrol-BSA-NPs outperformed free celastrol in lowering lipid accumulation, improving insulin sensitivity, and reducing inflammation in diet-induced obesity. Collectively, celastrol-BSA-NPs exhibited better bioavailability and in vivo efficacy in the treatment of diet-induced obesity. Importantly, such albumin-based nanoparticles may be a general biocompatible drug carrier system for the controlled release of hydrophobic compounds (e.g., celastrol) for the treatment of obesity and non-alcoholic fatty liver disease.
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Affiliation(s)
- Ni Fan
- School of Chinese Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, 10 Sassoon Road, Pokfulam, Hong Kong 999077, China.
| | - Jia Zhao
- School of Chinese Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, 10 Sassoon Road, Pokfulam, Hong Kong 999077, China.
| | - Wei Zhao
- School of Chinese Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, 10 Sassoon Road, Pokfulam, Hong Kong 999077, China.
| | - Yanting Shen
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong 999077, China
| | - Qingchun Song
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong 999077, China
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong 999077, China
| | - Yu Wang
- Department of Pharmacology and Pharmacy, The University of Hong Kong, Pokfulam Road, Hong Kong 999077, China
| | - Jianhui Rong
- School of Chinese Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, 10 Sassoon Road, Pokfulam, Hong Kong 999077, China. .,Shenzhen Institute of Research and Innovation, The University of Hong Kong, Shenzhen 518000, China
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Pan Y, Lee LH, Yang Z, Hassan SU, Shum HC. Co-doping optimized hydrogel-elastomer micro-actuators for versatile biomimetic motions. Nanoscale 2021; 13:18967-18976. [PMID: 34730168 DOI: 10.1039/d1nr05757j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Hydrogels can respond to changes in humidity or temperature, while elastomers can resist structural collapse due to dehydration or external force application. A hybrid bilayer of hydrogel-elastomers while retaining the merits of both the hydrogels and elastomers has emerged as a promising stimuli-responsive micro-actuator. However, the preparation of a hydrogel-elastomer micro-actuator requires multiple steps, mainly due to the differences in the surface properties of these two materials. Among them, the steps to surface-treat the elastomer and functionalize the material of each layer involve intricate processes and excessive consumption of resources. In this work, we introduce a co-doping method to optimize the preparation of a stimuli-responsive hydrogel-elastomer micro-actuator. The surface treatment and functionalization processes are combined into one step by directly doping the polymerization initiator and functional nanomaterials into the hybrid bilayer. The thermo-responsive hydrogel is combined with a photothermal elastomer to fabricate a soft micro-actuator that can bend and unbend in response to changes in humidity and light. Based on this actuator, a set of biomimetic soft micro-robots were developed, demonstrating a series of motions, such as grabbing, crawling, and jumping. This strategy of stimuli-responsive micro-actuator preparation can benefit the hydrogel-elastomer hybrid micro-robot designs for applications ranging from self-locomotive robots in environmental monitoring to drug delivery in biomedical engineering.
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Affiliation(s)
- Yi Pan
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China.
| | - Lik Ho Lee
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China.
| | - Zhenyu Yang
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China.
| | - Sammer Ul Hassan
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China.
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China.
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Wong HL, Hung LT, Kwok SS, Bu Y, Lin Y, Shum HC, Wang H, Lo ACY, Yam GHF, Jhanji V, Shih KC, Chan YK. The anti-scarring role of Lycium barbarum polysaccharide on cornea epithelial-stromal injury. Exp Eye Res 2021; 211:108747. [PMID: 34450184 DOI: 10.1016/j.exer.2021.108747] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 08/07/2021] [Accepted: 08/22/2021] [Indexed: 12/16/2022]
Abstract
PURPOSE Cornea epithelial-stromal scarring is related to the differentiation of fibroblasts into opaque myofibroblasts. Our study aims to assess the effectiveness of Lycium barbarum polysaccharide (LBP) solution as a pre-treatment in minimizing corneal scarring. METHODS Human corneal fibroblasts were cultured in a three-dimensional collagen type I-based hydrogel in an eye-on-a-chip model. Fibroblasts were pre-treated with 2 mg/mL LBP for 24 h, followed by another 24-h incubation with 10 ng/mL transforming growth factor-beta 1 (TGF-β1) to induce relevant physiological events after stromal injury. Intracellular pro-fibrotic proteins, extracellular matrix proteins, and pro-inflammatory cytokines that involved in fibrosis, were assessed using immunocytochemistry and enzyme-linked immunosorbent assays. RESULTS Compared to the positive control TGF-β1 group, LBP pre-treated cells had a significantly lower expression of alpha-smooth muscle actin, marker of myofibroblasts, vimentin (p < 0.05), and also extracellular matrix proteins both collagen type II and type III (p < 0.05) that can be found in scar tissues. Moreover, LBP pre-treated cells had a significantly lower secretion of pro-inflammatory cytokines interleukin-6 and interleukin-8 (p < 0.05). The cell-laden hydrogel contraction and stiffness showed no significant difference between LBP pre-treatment and control groups. Fibroblasts pretreated with LBP as well had reduced angiogenic factors expression and suppression of undesired proliferation (p < 0.05). CONCLUSION Our results showed that LBP reduced both pro-fibrotic proteins and pro-inflammatory cytokines on corneal injury in vitro. We suggest that LBP, as a natural Traditional Chinese Medicine, may potentially be a novel topical pre-treatment option prior to corneal refractive surgeries with an improved prognosis.
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Affiliation(s)
- Ho Lam Wong
- Department of Ophthalmology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region
| | - Lap Tak Hung
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Hong Kong Special Administrative Region
| | - Sum Sum Kwok
- Department of Ophthalmology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region
| | - Yashan Bu
- Department of Ophthalmology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region
| | - Yuan Lin
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Hong Kong Special Administrative Region
| | - Ho Cheung Shum
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Hong Kong Special Administrative Region
| | - Hua Wang
- Eye Center of Xiangya Hospital, Central South University, China; Hunan Key Laboratory of Ophthalmology, China
| | - Amy Cheuk Yin Lo
- Department of Ophthalmology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region
| | - Gary Hin Fai Yam
- Department of Ophthalmology, University of Pittsburgh Medical Centre, USA
| | - Vishal Jhanji
- Department of Ophthalmology, University of Pittsburgh Medical Centre, USA
| | - Kendrick Co Shih
- Department of Ophthalmology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region.
| | - Yau Kei Chan
- Department of Ophthalmology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region.
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Yuan H, Tian J, Chao Y, Chien YS, Luo RH, Guo JY, Li S, Chou YJ, Shum HC, Chen CF. Hand-Powered Microfluidics for Parallel Droplet Digital Loop-Mediated Isothermal Amplification Assays. ACS Sens 2021; 6:2868-2874. [PMID: 34156242 DOI: 10.1021/acssensors.1c00184] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Droplet digital loop-mediated isothermal amplification (ddLAMP) is an important assay for pathogen detection due to its high accuracy, specificity, and ability to quantify nucleic acids. However, performing ddLAMP requires expensive instrumentation and the need for highly trained personnel with expertise in microfluidics. To make ddLAMP more accessible, a ddLAMP assay is developed, featuring significantly decreased operational difficulty and instrumentation requirements. The proposed assay consists of three simplified steps: (1) droplet generation step, in which a LAMP mixture can be emulsified just by manually pulling a syringe connected to a microfluidic device. In this step, for the first time, we verify that highly monodispersed droplets can be generated with unstable flow rates or pressures, allowing untrained personnel to operate the microfluidic device and perform ddLAMP assay; (2) heating step, in which the droplets are isothermally heated in a water bath, which can be found in most laboratories; and (3) result analysis step, in which the ddLAMP result can be determined using only a fluorescence microscopy and an open-source analyzing software. Throughout the process, no droplet microfluidic expertise or equipment is required. More importantly, the proposed system enables multiple samples to be processed simultaneously with a detection limit of 10 copies/μL. The test is simple and intuitive to operate in most laboratories for multi-sample detection, significantly enhancing the accessibility and detection throughput of the ddLAMP technique.
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Affiliation(s)
- Hao Yuan
- School of Life Sciences and Engineering, Southwest Jiaotong University, Chengdu, Sichuan 610031, China
- Institute of Applied Mechanics, National Taiwan University, Taipei 106, Taiwan
| | - Jingxuan Tian
- Department of Mechanical Engineering, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - Youchuang Chao
- Department of Mechanical Engineering, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - Yuh-Shiuan Chien
- Institute of Applied Mechanics, National Taiwan University, Taipei 106, Taiwan
| | - Ren-Hao Luo
- Institute of Applied Mechanics, National Taiwan University, Taipei 106, Taiwan
| | - Jun-Yu Guo
- Institute of Applied Mechanics, National Taiwan University, Taipei 106, Taiwan
| | - Shanshan Li
- Department of Clinical Oncology, The University of Hong Kong-Shenzhen Hospital, Shenzhen 518009, China
| | - Yi-Ju Chou
- Institute of Applied Mechanics, National Taiwan University, Taipei 106, Taiwan
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - Chien-Fu Chen
- Institute of Applied Mechanics, National Taiwan University, Taipei 106, Taiwan
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Chen M, Hu S, Zhou Z, Huang N, Lee S, Zhang Y, Cheng R, Yang J, Xu Z, Liu Y, Lee H, Huan X, Feng SP, Shum HC, Chan BP, Seol SK, Pyo J, Tae Kim J. Three-Dimensional Perovskite Nanopixels for Ultrahigh-Resolution Color Displays and Multilevel Anticounterfeiting. Nano Lett 2021; 21:5186-5194. [PMID: 34125558 DOI: 10.1021/acs.nanolett.1c01261] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Hybrid perovskites are emerging as a promising, high-performance luminescent material; however, the technological challenges associated with generating high-resolution, free-form perovskite structures remain unresolved, limiting innovation in optoelectronic devices. Here, we report nanoscale three-dimensional (3D) printing of colored perovskite pixels with programmed dimensions, placements, and emission characteristics. Notably, a meniscus comprising femtoliters of ink is used to guide a highly confined, out-of-plane crystallization process, which generates 3D red, green, and blue (RGB) perovskite nanopixels with ultrahigh integration density. We show that the 3D form of these nanopixels enhances their emission brightness without sacrificing their lateral resolution, thereby enabling the fabrication of high-resolution displays with improved brightness. Furthermore, 3D pixels can store and encode additional information into their vertical heights, providing multilevel security against counterfeiting. The proof-of-concept experiments demonstrate the potential of 3D printing to become a platform for the manufacture of smart, high-performance photonic devices without design restrictions.
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Affiliation(s)
- Mojun Chen
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, People's Republic of China
| | - Shiqi Hu
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, People's Republic of China
| | - Zhiwen Zhou
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, People's Republic of China
| | - Nan Huang
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, People's Republic of China
| | - Sanghyeon Lee
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, People's Republic of China
| | - Yage Zhang
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, People's Republic of China
| | - Rui Cheng
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, People's Republic of China
| | - Jihyuk Yang
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, People's Republic of China
| | - Zhaoyi Xu
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, People's Republic of China
| | - Yu Liu
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, People's Republic of China
| | - Heekwon Lee
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, People's Republic of China
| | - Xiao Huan
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, People's Republic of China
| | - Shien-Ping Feng
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, People's Republic of China
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, People's Republic of China
| | - Barbara Pui Chan
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, People's Republic of China
| | - Seung Kwon Seol
- Nano Hybrid Technology Research Center, Korea Electrotechnology Research Institute (KERI), Changwon-si, Gyeongsangnam-do 51543, Republic of Korea
- Electrical-Functionality Materials Engineering, Korea University of Science and Technology (UST), Changwon-si, Gyeongsangnam-do 51543, Republic of Korea
| | - Jaeyeon Pyo
- Nano Hybrid Technology Research Center, Korea Electrotechnology Research Institute (KERI), Changwon-si, Gyeongsangnam-do 51543, Republic of Korea
| | - Ji Tae Kim
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, People's Republic of China
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Guo W, Kinghorn AB, Zhang Y, Li Q, Poonam AD, Tanner JA, Shum HC. Non-associative phase separation in an evaporating droplet as a model for prebiotic compartmentalization. Nat Commun 2021; 12:3194. [PMID: 34045455 PMCID: PMC8160217 DOI: 10.1038/s41467-021-23410-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 04/22/2021] [Indexed: 11/13/2022] Open
Abstract
The synthetic pathways of life’s building blocks are envisaged to be through a series of complex prebiotic reactions and processes. However, the strategy to compartmentalize and concentrate biopolymers under prebiotic conditions remains elusive. Liquid-liquid phase separation is a mechanism by which membraneless organelles form inside cells, and has been hypothesized as a potential mechanism for prebiotic compartmentalization. Associative phase separation of oppositely charged species has been shown to partition RNA, but the strongly negative charge exhibited by RNA suggests that RNA-polycation interactions could inhibit RNA folding and its functioning inside the coacervates. Here, we present a prebiotically plausible pathway for non-associative phase separation within an evaporating all-aqueous sessile droplet. We quantitatively investigate the kinetic pathway of phase separation triggered by the non-uniform evaporation rate, together with the Marangoni flow-driven hydrodynamics inside the sessile droplet. With the ability to undergo liquid-liquid phase separation, the drying droplets provide a robust mechanism for formation of prebiotic membraneless compartments, as demonstrated by localization and storage of nucleic acids, in vitro transcription, as well as a three-fold enhancement of ribozyme activity. The compartmentalization mechanism illustrated in this model system is feasible on wet organophilic silica-rich surfaces during early molecular evolution. Prebiotic compartmentalization could prove essential for the evolution of life. Guo et al. show that liquid-liquid separation in an aqueous two-phase system driven by evaporation may already suffice to facilitate chemical processes required for the RNA world hypothesis.
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Affiliation(s)
- Wei Guo
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Hong Kong (SAR), Hong Kong, China
| | - Andrew B Kinghorn
- School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong (SAR), Hong Kong, China
| | - Yage Zhang
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Hong Kong (SAR), Hong Kong, China
| | - Qingchuan Li
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Hong Kong (SAR), Hong Kong, China.,School of Chemistry & Chemical Engineering, National Engineering Research Center for Colloidal Materials, Shandong University, Jinan, 250100, China
| | - Aditi Dey Poonam
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Hong Kong (SAR), Hong Kong, China
| | - Julian A Tanner
- School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong (SAR), Hong Kong, China. .,Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong (SAR), Hong Kong, China.
| | - Ho Cheung Shum
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Hong Kong (SAR), Hong Kong, China. .,Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong (SAR), Hong Kong, China.
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Song Q, Chao Y, Zhang Y, Shum HC. Controlled Formation of All-Aqueous Janus Droplets by Liquid-Liquid Phase Separation of an Aqueous Three-Phase System. J Phys Chem B 2021; 125:562-570. [PMID: 33416329 DOI: 10.1021/acs.jpcb.0c09884] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Janus droplets have been demonstrated in a wide range of applications, ranging from drug delivery, to biomedical imaging, to bacterial detection. However, existing fabrication strategies often involve nonaqueous solvents, such as organic solvent or oil, which largely limits their use in fields that require a high degree of biocompatibility. Here, we present a method to achieve all-aqueous Janus droplets by liquid-liquid phase separation of an aqueous three-phase system (A3PS). An aqueous droplet containing two initially miscible polymers is first injected into an aqueous solution of another concentrated polymer, and then it spontaneously phase-separates into a Janus droplet due to the diffusive mass exchange between the drop and bulk phases during equilibration. To achieve continuous generation of the Janus droplets, the A3PS is further integrated with microfluidics and electrospray. The size and shape of the phase-separated Janus droplets can be easily controlled by tuning the operation parameters, such as the flow rate and/or the initial composition of the drop phases. Dumbbell-shaped and snowman-shaped Janus droplets with average sizes between 100 and 400 μm can be generated by both coflow microfluidics and electrospray. In particular, the phase-separated Janus droplets can simultaneously load two different liposomes into each compartment, which are promising carriers for combination drugs. The obtained Janus droplets are superior templates for biocompatible materials, which can serve as building blocks such as high-order droplet patterns for constructing advanced biomaterials.
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Affiliation(s)
- Qingchun Song
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Hong Kong (SAR), China
| | - Youchuang Chao
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Hong Kong (SAR), China
| | - Yage Zhang
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Hong Kong (SAR), China
| | - Ho Cheung Shum
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Hong Kong (SAR), China
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Abstract
Emerging wearable and implantable biodevices have been significantly revolutionizing the diagnosis and treatment of disease. However, the geometrical mismatch between tissues and biodevices remains a great challenge for achieving optimal performances and functionalities for biodevices. Shape-adaptable biodevices enabling active compliance with human body tissues offer promising opportunities for addressing the challenge through programming their geometries on demand. This article reviews the design principles and control strategies for shape-adaptable biodevices with programmable shapes and actively compliant capabilities, which have offered innovative diagnostic/therapeutic tools and facilitated a variety of wearable and implantable applications. The state-of-the-art progress in applications of shape-adaptable biodevices in the fields of smart textiles, wound care, healthcare monitoring, drug and cell delivery, tissue repair and regeneration, nerve stimulation and recording, and biopsy and surgery, is highlighted. Despite the remarkable advances already made, shape-adaptable biodevices still confront many challenges on the road toward the clinic, such as enhanced intelligence for actively sensing and operating in response to physiological environments. Next-generation paradigms will shed light on future directions for extending the breadth and performance of shape-adaptable biodevices for wearable and implantable applications.
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Affiliation(s)
- Qilong Zhao
- Institute of Biomedical & Health Engineering, Shenzhen Institutes of Advanced Technology (SIAT), Chinese Academy of Sciences (CAS), Shenzhen, 518035 China.
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42
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Zhu S, Forth J, Xie G, Chao Y, Tian J, Russell TP, Shum HC. Rapid Multilevel Compartmentalization of Stable All-Aqueous Blastosomes by Interfacial Aqueous-Phase Separation. ACS Nano 2020; 14:11215-11224. [PMID: 32515582 DOI: 10.1021/acsnano.0c02923] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Producing artificial multicellular structures to process multistep cascade reactions and mimic the fundamental aspects of living systems is an outstanding challenge. Highly biocompatible, artificial systems consisting of all-aqueous, compartmentalized multicellular systems have yet to be realized. Here, a rapid multilevel compartmentalization of an all-aqueous system where a 3D sheet of subcolloidosomes encloses a mother colloidosome by interfacial phase separation is demonstrated. These spatially organized multicellular structures are termed "blastosomes" since they are similar to blastula in appearance. The barrier to nanoparticle assembly at the water-water interface is overcome using oppositely charged polyelectrolytes that form a coacervate-nanoparticle-composite network. The conditions required to trigger interfacial phase separation and form blastosomes are quantified in a mapped state diagram. We show a versatile model for constructing artificial multicellular spheroids in all-aqueous systems. The rapid interfacial assembly of charged particles and polyelectrolytes can lock in nonequilibrium shapes of water, which also enables top-down technologies, such as 3D printing and microfluidics, to program flexible compartmentalized structures.
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Affiliation(s)
- Shipei Zhu
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
- The University of Hong Kong-Shenzhen Institute for Research and Innovation (HKU-SIRI), Shenzhen 518000, China
| | - Joe Forth
- Materials Sciences Division, Lawrence Berkeley National Laboratory, One Cyclotron Road, California 94720, United States
| | - Ganhua Xie
- Materials Sciences Division, Lawrence Berkeley National Laboratory, One Cyclotron Road, California 94720, United States
| | - Youchuang Chao
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
- The University of Hong Kong-Shenzhen Institute for Research and Innovation (HKU-SIRI), Shenzhen 518000, China
| | - Jingxuan Tian
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
- The University of Hong Kong-Shenzhen Institute for Research and Innovation (HKU-SIRI), Shenzhen 518000, China
| | - Thomas P Russell
- Materials Sciences Division, Lawrence Berkeley National Laboratory, One Cyclotron Road, California 94720, United States
- Polymer Science and Engineering Department, University of Massachusetts, 120 Governors Drive, Conte Center for Polymer Research, Amherst, Massachusetts 01003, United States
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China
- WPI-Advanced Institute for Materials Research (WPI-AIMR), Tohoku University, 2-1-1 Katahira, Aoba, Sendai 980-8577, Japan
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
- The University of Hong Kong-Shenzhen Institute for Research and Innovation (HKU-SIRI), Shenzhen 518000, China
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43
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Nan L, Cao Y, Yuan S, Shum HC. Oil-mediated high-throughput generation and sorting of water-in-water droplets. Microsyst Nanoeng 2020; 6:70. [PMID: 34567680 PMCID: PMC8433215 DOI: 10.1038/s41378-020-0180-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2020] [Revised: 04/17/2020] [Accepted: 05/06/2020] [Indexed: 05/27/2023]
Abstract
Aqueous two-phase system (ATPS) droplets have demonstrated superior compatibility over conventional water-in-oil droplets for various biological assays. However, the ultralow interfacial tension hampers efficient and stable droplet generation, limiting further development and more extensive use of such approaches. Here, we present a simple strategy to employ oil as a transient medium for ATPS droplet generation. Two methods based on passive flow focusing and active pico-injection are demonstrated to generate water-water-oil double emulsions, achieving a high generation frequency of ~2.4 kHz. Through evaporation of the oil to break the double emulsions, the aqueous core can be released to form uniform-sized water-in-water droplets. Moreover, this technique can be used to fabricate aqueous microgels, and the introduction of the oil medium enables integration of droplet sorting to produce single-cell-laden hydrogels with a harvest rate of over 90%. We believe that the demonstrated high-throughput generation and sorting of ATPS droplets represent an important tool to advance droplet-based tissue engineering and single-cell analyses.
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Affiliation(s)
- Lang Nan
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Yang Cao
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Shuai Yuan
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
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Tian J, Ribe NM, Wu X, Shum HC. Steady and Unsteady Buckling of Viscous Capillary Jets and Liquid Bridges. Phys Rev Lett 2020; 125:104502. [PMID: 32955312 DOI: 10.1103/physrevlett.125.104502] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 06/02/2020] [Accepted: 07/23/2020] [Indexed: 06/11/2023]
Abstract
Steady buckling (coiling) of thin falling liquid jets is sensitive to surface tension, yet an understanding of these capillary effects lags far behind what is known about surface-tension-free coiling. In experiments with submillimetric jets and ultralow flow rates, we find that the critical dispensing height H_{c} for coiling decreases with increasing flow rate, a trend opposite to that found previously for inertia-free coiling. We resolve the apparent contradiction using nonlinear numerical simulations based on slender-jet theory which show that the trend reversal is due to the strong effect of surface tension in our experiments. We use our experiments to construct a regime diagram (coiling vs stagnation flow) in the space of capillary number Ca and jet slenderness ε and find that it agrees well with fully nonlinear numerical simulations. However, it differs substantially from the analogous regime diagram determined experimentally by Le Merrer, Quéré, and Clanet [Phys. Rev. Lett. 109, 064502 (2012)PRLTAO0031-900710.1103/PhysRevLett.109.064502] for the unsteady buckling of a compressed liquid bridge. Using linear stability analysis, we show that the differences between the two regime diagrams can be explained by a combination of shape nonuniformity and the influence of gravity.
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Affiliation(s)
- Jingxuan Tian
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Neil M Ribe
- Lab FAST, University Paris-Saclay, CNRS, Bât. 530, Campus Univ, 91400 Orsay, France
| | - Xiaoxiao Wu
- Faculties of Sciences and Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
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Chao Y, Hung LT, Feng J, Yuan H, Pan Y, Guo W, Zhang Y, Shum HC. Flower-like droplets obtained by self-emulsification of a phase-separating (SEPS) aqueous film. Soft Matter 2020; 16:6050-6055. [PMID: 32490476 DOI: 10.1039/d0sm00660b] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Self-emulsification, referring to the spontaneous formation of droplets of one phase in another immiscible phase, is attracting growing interest because of its simplicity in creating droplets. Existing self-emulsification methods usually rely on phase inversion, temperature cycling, and solvent evaporation. However, achieving spatiotemporal control over the morphology of self-emulsified droplets remains challenging. In this work, a conceptually new approach of creating both simple and complex droplets by self-emulsification of a phase-separating (SEPS) aqueous film, is reported. The aqueous film is formed by depositing a surfactant-laden aqueous droplet onto an aqueous surface, and the fragmentation of the film into droplets is triggered by a wetting transition. Smaller and more uniform droplets can be achieved by introducing liquid-liquid phase separation (LLPS). Moreover, properly modulating quadruple LLPS and film fragmentation enables the creation of highly multicellular droplets such as flower-like droplets stabilized by the interfacial self-assembly of nanoparticles. This work provides a novel strategy to design aqueous droplets by LLPS, and it will inspire a wide range of applications such as membraneless organelle synthesis, cell mimics and delivery.
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Affiliation(s)
- Youchuang Chao
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China.
| | - Lap Tak Hung
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China.
| | - Jie Feng
- Department of Mechanical Science and Engineering, University of Illinois at Urbana Champaign Urbana, Illinois 61801, USA
| | - Hao Yuan
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China. and Institute of Applied Mechanics, National Taiwan University, Taipei, Taiwan
| | - Yi Pan
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China.
| | - Wei Guo
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China.
| | - Yage Zhang
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China.
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China.
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Wiraja C, Siantoputri ME, Liu S, Shum HC, Xu C. Unraveling Framework Nucleic Acid-Skin Cell Interactions with a Co-Culture System. ACTA ACUST UNITED AC 2020; 4:e1900169. [PMID: 32293123 DOI: 10.1002/adbi.201900169] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 10/14/2019] [Indexed: 11/08/2022]
Abstract
Framework nucleic acid (FNA) is an emerging drug carrier platform, with its biodegradability and uniform, tunable structures. Recently, its applicability in transdermal drug delivery has been demonstrated, extending the range of applications that are predominantly based on intravenous injection. However, FNA's interaction and impact toward the skin cells are yet to be elucidated. This study employs an optically clear keratinocyte/fibroblast co-culture system to visualize the FNA-skin cell interactions. FNA's influence on these cells is evaluated through polymerase chain reaction analyses and metabolism assays. A size-dependent interaction and cellular internalization on both keratinocytes and fibroblasts is observed, with no adverse effects on cell viability and functions.
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Affiliation(s)
- Christian Wiraja
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, 637459, Singapore, Singapore
| | - Maria Esterlita Siantoputri
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, 637459, Singapore, Singapore
| | - Sihan Liu
- Department of Mechanical Engineering, The University of Hong Kong, Haking Wong Building, Pokfulam Road, 999077, Pokfulam, Hong Kong
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Haking Wong Building, Pokfulam Road, 999077, Pokfulam, Hong Kong
| | - Chenjie Xu
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, 637459, Singapore, Singapore.,National Dental Centre of Singapore, 5 Second Hospital Ave, 168938, Singapore, Singapore
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Abstract
Natural and man-made robotic systems use the interfacial tension between two fluids to support dense objects on liquid surfaces. Here, we show that coacervate-encased droplets of an aqueous polymer solution can be hung from the surface of a less dense aqueous polymer solution using surface tension. The forces acting on and the shapes of the hanging droplets can be controlled. Sacs with homogeneous and heterogeneous surfaces are hung from the surface and, by capillary forces, form well-ordered arrays. Locomotion and rotation can be achieved by embedding magnetic microparticles within the assemblies. Direct contact of the droplet with air enables in situ manipulation and compartmentalized cascading chemical reactions with selective transport. Applications including functional microreactors, motors, and biomimetic robots are evident.
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Affiliation(s)
- Ganhua Xie
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
- Polymer Science and Engineering Department, University of Massachusetts, Amherst, MA 01003
| | - Joe Forth
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
- Department of Chemistry, University College London, London WC1H 0AJ, United Kingdom
| | - Shipei Zhu
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong SAR, China
| | - Brett A Helms
- The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - Paul D Ashby
- The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong SAR, China
| | - Thomas P Russell
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720;
- Polymer Science and Engineering Department, University of Massachusetts, Amherst, MA 01003
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China
- Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan
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Ma Q, Song Y, Sun W, Cao J, Yuan H, Wang X, Sun Y, Shum HC. Cell-Inspired All-Aqueous Microfluidics: From Intracellular Liquid-Liquid Phase Separation toward Advanced Biomaterials. Adv Sci (Weinh) 2020; 7:1903359. [PMID: 32274317 PMCID: PMC7141073 DOI: 10.1002/advs.201903359] [Citation(s) in RCA: 84] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2019] [Revised: 01/06/2020] [Indexed: 05/24/2023]
Abstract
Living cells have evolved over billions of years to develop structural and functional complexity with numerous intracellular compartments that are formed due to liquid-liquid phase separation (LLPS). Discovery of the amazing and vital roles of cells in life has sparked tremendous efforts to investigate and replicate the intracellular LLPS. Among them, all-aqueous emulsions are a minimalistic liquid model that recapitulates the structural and functional features of membraneless organelles and protocells. Here, an emerging all-aqueous microfluidic technology derived from micrometer-scaled manipulation of LLPS is presented; the technology enables the state-of-art design of advanced biomaterials with exquisite structural proficiency and diversified biological functions. Moreover, a variety of emerging biomedical applications, including encapsulation and delivery of bioactive gradients, fabrication of artificial membraneless organelles, as well as printing and assembly of predesigned cell patterns and living tissues, are inspired by their cellular counterparts. Finally, the challenges and perspectives for further advancing the cell-inspired all-aqueous microfluidics toward a more powerful and versatile platform are discussed, particularly regarding new opportunities in multidisciplinary fundamental research and biomedical applications.
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Affiliation(s)
- Qingming Ma
- Department of PharmaceuticsSchool of PharmacyQingdao UniversityQingdao266021China
| | - Yang Song
- Wallace H Coulter Department of Biomedical EngineeringGeorgia Institute of Technology & Emory School of MedicineAtlantaGA30332USA
| | - Wentao Sun
- Center for Basic Medical ResearchTEDA International Cardiovascular HospitalChinese Academy of Medical Sciences & Peking Union Medical CollegeTianjin300457China
| | - Jie Cao
- Department of PharmaceuticsSchool of PharmacyQingdao UniversityQingdao266021China
| | - Hao Yuan
- Institute of Applied MechanicsNational Taiwan UniversityTaipei10617Taiwan
| | - Xinyu Wang
- Institute of Thermal Science and TechnologyShandong UniversityJinan250061China
| | - Yong Sun
- Department of PharmaceuticsSchool of PharmacyQingdao UniversityQingdao266021China
| | - Ho Cheung Shum
- Department of Mechanical EngineeringUniversity of Hong KongPokfulam RoadHong Kong
- HKU‐Shenzhen Institute of Research and Innovation (HKU‐SIRI)Shenzhen518000China
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Nan L, Lai MYA, Tang MYH, Chan YK, Poon LLM, Shum HC. On-Demand Droplet Collection for Capturing Single Cells. Small 2020; 16:e1902889. [PMID: 31448532 DOI: 10.1002/smll.201902889] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 07/26/2019] [Indexed: 06/10/2023]
Abstract
Droplet-based microfluidic techniques are extensively used in efficient manipulation and genome-wide analysis of individual cells, probing the heterogeneity among populations of individuals. However, the extraction and isolation of single cells from individual droplets remains difficult due to the inevitable sample loss during processing. Herein, an automated system for accurate collection of defined numbers of droplets containing single cells is presented. Based on alternate sorting and dispensing in three branch channels, the droplet number can be precisely controlled down to single-droplet resolution. While encapsulating single cells and reserving one branch as a waste channel, sorting can be seamlessly integrated to enable on-demand collection of single cells. Combined with a lossless recovery strategy, this technique achieves capture and culture of individual cells with a harvest rate of over 95%. The on-demand droplet collection technique has great potential to realize quantitative processing and analysis of single cells for elucidating the role of cell-to-cell variations.
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Affiliation(s)
- Lang Nan
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, 999077, Hong Kong
| | - Man Yuk Alison Lai
- School of Public Health, The University of Hong Kong, Pokfulam Road, Hong Kong, 999077, Hong Kong
| | - Matthew Yuk Heng Tang
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, 999077, Hong Kong
| | - Yau Kei Chan
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, 999077, Hong Kong
- Department of Ophthalmology, The University of Hong Kong, Pokfulam Road, Hong Kong, 999077, Hong Kong
| | - Leo Lit Man Poon
- School of Public Health, The University of Hong Kong, Pokfulam Road, Hong Kong, 999077, Hong Kong
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, 999077, Hong Kong
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50
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Yuan H, Chao Y, Shum HC. Droplet and Microchamber-Based Digital Loop-Mediated Isothermal Amplification (dLAMP). Small 2020; 16:e1904469. [PMID: 31899592 DOI: 10.1002/smll.201904469] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2019] [Revised: 10/22/2019] [Indexed: 05/15/2023]
Abstract
Digital loop-mediated isothermal amplification (dLAMP) refers to compartmentalizing nucleic acids and LAMP reagents into a large number of individual partitions, such as microchambers and droplets. This compartmentalization enables dLAMP to be an excellent platform to quantify the absolute number of the target nucleic acids. Owing to its low requirement for instrumentation complexity, high specificity, and strong tolerance to inhibitors in the nucleic acid samples, dLAMP has been recognized as a simple and accurate technique to quantify pathogenic nucleic acid. Herein, the general process of dLAMP techniques is summarized, the current dLAMP techniques are categorized, and a comprehensive discussion on different types of dLAMP techniques is presented. Also, the challenges of the current dLAMP are illustrated together with the possible strategies to address these challenges. In the end, the future directions of the dLAMP developments, including multitarget detection, multisample detection, and processing nucleic acid extraction are outlined. With recently significant advances in dLAMP, this technology has the potential to see more widespread use beyond the laboratory in the future.
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Affiliation(s)
- Hao Yuan
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, Hong Kong
| | - Youchuang Chao
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, Hong Kong
| | - Ho Cheung Shum
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, Hong Kong
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