1
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Lenhart A, Kennedy RT. Evaluation of Surface Treatments of PDMS Microfluidic Devices for Improving Small-Molecule Recovery with Application to Monitoring Metabolites Secreted from Islets of Langerhans. ACS MEASUREMENT SCIENCE AU 2023; 3:380-389. [PMID: 37868359 PMCID: PMC10588933 DOI: 10.1021/acsmeasuresciau.3c00025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 07/14/2023] [Accepted: 07/17/2023] [Indexed: 10/24/2023]
Abstract
Microfluidic devices are becoming an important tool for bioanalysis with applications including studying cell secretion, cell growth, and drug delivery. Small molecules such as drugs, cell products, or nutrients may partition into polydimethylsiloxane (PDMS), a commonly used material for microfluidic devices, potentially leading to poor recovery or inaccurate delivery of such chemicals. To decrease small-molecule partitioning, surface and bulk PDMS treatments have been developed; however, these have been tested on few analytes, or their biocompatibility are unknown. Studies often focus on one analyte, whereas a diversity of chemicals are of interest and possibly affected. In this study, 11 device treatments are tested and applied to 21 biologically relevant small molecules with a variety of chemical structures. Device treatments are characterized using water contact angle measurements and evaluated by measuring recovery of the 21 target analytes using liquid chromatography-mass spectrometry. 1,5-Dimethyl-1,5-diazaundecamethylene polymethobromide (polybrene), a positively charged polymer, produced the least hydrophilic surface and was found to provide the best recovery with most of the analytes having >50% recovery and up to 92% recovery; however, recovery varied by analyte highlighting the importance of analyte diversity rather than targeting a single analyte in evaluating treatments. A polybrene-treated device was applied to investigate secretion from pancreatic islets, which are micro-organs involved in glucose homeostasis and diabetes. Islets secrete small molecules that have been shown to modulate the secretion of islets' main functional products, glucose-regulating hormones. The polybrene treatment enabled the detection of 20 target analytes from islets-on-chip during isosmotic and hypo-osmotic glucose perfusions and resulted in detection of more significant secretion changes compared to untreated PDMS.
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Affiliation(s)
- Ashley
E. Lenhart
- Department
of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Robert T. Kennedy
- Department
of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department
of Pharmacology, University of Michigan, Ann Arbor, Michigan 48109, United States
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2
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Kang YJ, Diep YN, Tran M, Tran VTA, Ambrin G, Ngo H, Cho H. Three-dimensional human neural culture on a chip recapitulating neuroinflammation and neurodegeneration. Nat Protoc 2023; 18:2838-2867. [PMID: 37542184 DOI: 10.1038/s41596-023-00861-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Accepted: 05/30/2023] [Indexed: 08/06/2023]
Abstract
Neuroinflammation has either beneficial or detrimental effects, depending on risk factors and neuron-glia interactions in neurological disorders. However, studying neuroinflammation has been challenging due to the complexity of cell-cell interactions and lack of physio-pathologically relevant neuroinflammatory models. Here, we describe our three-dimensional microfluidic multicellular human neural culture model, referred to as a 'brain-on-a-chip' (BoC). This elucidates neuron-glia interactions in a controlled manner and recapitulates pathological signatures of the major neurological disorders: dementia, brain tumor and brain edema. This platform includes a chemotaxis module offering a week-long, stable chemo-gradient compared with the few hours in other chemotaxis models. Additionally, compared with conventional brain models cultured with mixed phenotypes of microglia, our BoC can separate the disease-associated microglia out of heterogeneous population and allow selective neuro-glial engagement in three dimensions. This provides benefits of interpreting the neuro-glia interactions while revealing that the prominent activation of innate immune cells is the risk factor leading to synaptic impairment and neuronal loss, validated in our BoC models of disorders. This protocol describes how to fabricate and implement our human BoC, manipulate in real time and perform end-point analyses. It takes 2 d to set up the device and cell preparations, 1-9 weeks to develop brain models under disease conditions and 2-3 d to carry out analyses. This protocol requires at least 1 month training for researchers with basic molecular biology techniques. Taken together, our human BoCs serve as reliable and valuable platforms to investigate pathological mechanisms involving neuroinflammation and to assess therapeutic strategies modulating neuroinflammation in neurological disorders.
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Affiliation(s)
- You Jung Kang
- Institute of Quantum Biophysics, Sungkyunkwan University, Suwon, Republic of Korea
- Department of Biophysics, Sungkyunkwan University, Suwon, Republic of Korea
| | - Yen N Diep
- Institute of Quantum Biophysics, Sungkyunkwan University, Suwon, Republic of Korea
- Department of Biophysics, Sungkyunkwan University, Suwon, Republic of Korea
- Department of Intelligent Precision Healthcare Convergence, Sungkyunkwan University, Suwon, Republic of Korea
| | - Minh Tran
- Institute of Quantum Biophysics, Sungkyunkwan University, Suwon, Republic of Korea
- Department of Biophysics, Sungkyunkwan University, Suwon, Republic of Korea
- Department of Intelligent Precision Healthcare Convergence, Sungkyunkwan University, Suwon, Republic of Korea
| | - Van Thi Ai Tran
- Institute of Quantum Biophysics, Sungkyunkwan University, Suwon, Republic of Korea
- Department of Biophysics, Sungkyunkwan University, Suwon, Republic of Korea
| | - Ghuncha Ambrin
- Department of Psychiatry, School of Medicine, University of California San Diego, San Diego, CA, USA
| | - Huyen Ngo
- Institute of Quantum Biophysics, Sungkyunkwan University, Suwon, Republic of Korea
- Department of Biophysics, Sungkyunkwan University, Suwon, Republic of Korea
- Department of Intelligent Precision Healthcare Convergence, Sungkyunkwan University, Suwon, Republic of Korea
| | - Hansang Cho
- Institute of Quantum Biophysics, Sungkyunkwan University, Suwon, Republic of Korea.
- Department of Biophysics, Sungkyunkwan University, Suwon, Republic of Korea.
- Department of Intelligent Precision Healthcare Convergence, Sungkyunkwan University, Suwon, Republic of Korea.
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3
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Chen C, Rengarajan V, Kjar A, Huang Y. A matrigel-free method to generate matured human cerebral organoids using 3D-Printed microwell arrays. Bioact Mater 2021; 6:1130-1139. [PMID: 33134606 PMCID: PMC7577195 DOI: 10.1016/j.bioactmat.2020.10.003] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 09/05/2020] [Accepted: 10/06/2020] [Indexed: 12/11/2022] Open
Abstract
The current methods of generating human cerebral organoids rely excessively on the use of Matrigel or other external extracellular matrices (ECM) for cell micro-environmental modulation. Matrigel embedding is problematic for long-term culture and clinical applications due to high inconsistency and other limitations. In this study, we developed a novel microwell culture platform based on 3D printing. This platform, without using Matrigel or external signaling molecules (i.e., SMAD and Wnt inhibitors), successfully generated matured human cerebral organoids with robust formation of high-level features (i.e., wrinkling/folding, lumens, neuronal layers). The formation and timing were comparable or superior to the current Matrigel methods, yet with improved consistency. The effect of microwell geometries (curvature and resolution) and coating materials (i.e., mPEG, Lipidure, BSA) was studied, showing that mPEG outperformed all other coating materials, while curved-bottom microwells outperformed flat-bottom ones. In addition, high-resolution printing outperformed low-resolution printing by creating faithful, isotropically-shaped microwells. The trend of these effects was consistent across all developmental characteristics, including EB formation efficiency and sphericity, organoid size, wrinkling index, lumen size and thickness, and neuronal layer thickness. Overall, the microwell device that was mPEG-coated, high-resolution printed, and bottom curved demonstrated the highest efficacy in promoting organoid development. This platform provided a promising strategy for generating uniform and mature human cerebral organoids as an alternative to Matrigel/ECM-embedding methods.
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Affiliation(s)
| | | | - Andrew Kjar
- Department of Biological Engineering, Utah State University, Logan, UT, 84322, USA
| | - Yu Huang
- Department of Biological Engineering, Utah State University, Logan, UT, 84322, USA
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4
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Valero T, Delgado-González A, Unciti-Broceta JD, Cano-Cortés V, Pérez-López AM, Unciti-Broceta A, Sánchez Martín RM. Drug "Clicking" on Cell-Penetrating Fluorescent Nanoparticles for In Cellulo Chemical Proteomics. Bioconjug Chem 2018; 29:3154-3160. [PMID: 30122043 DOI: 10.1021/acs.bioconjchem.8b00481] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Chemical proteomics approaches are widely used to identify molecular targets of existing or novel drugs. This manuscript describes the development of a straightforward approach to conjugate azide-labeled drugs via click chemistry to alkyne-tagged cell-penetrating fluorescent nanoparticles as a novel tool to study target engagement and/or identification inside living cells. A modification of the Baeyer test for alkynes allows monitoring the Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) reaction, guaranteeing the presence of the drug on the solid support. As a proof of concept, the conjugation of the promiscuous kinase inhibitor dasatinib to Cy5-labeled nanoparticles is presented. Dasatinib-decorated fluorescent nanoparticles efficiently inhibited its protein target SRC in vitro, entered cancer cells, and colocalized with SRC in cellulo.
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Affiliation(s)
- Teresa Valero
- Cancer Research UK Edinburgh Centre, MRC Institute of Genetics & Molecular Medicine , University of Edinburgh , Edinburgh EH4 2XR , United Kingdom.,GENYO, Centre for Genomics and Oncological Research , Pfizer/University of Granada/Andalusian Regional Government , PTS Granada, Avda. Ilustración 114 , 18016 Granada , Spain.,Department of Medicinal & Organic Chemistry, Faculty of Pharmacy , University of Granada , Campus de Cartuja s/n , 18071 Granada , Spain
| | - Antonio Delgado-González
- GENYO, Centre for Genomics and Oncological Research , Pfizer/University of Granada/Andalusian Regional Government , PTS Granada, Avda. Ilustración 114 , 18016 Granada , Spain.,Department of Medicinal & Organic Chemistry, Faculty of Pharmacy , University of Granada , Campus de Cartuja s/n , 18071 Granada , Spain
| | - Juan Diego Unciti-Broceta
- GENYO, Centre for Genomics and Oncological Research , Pfizer/University of Granada/Andalusian Regional Government , PTS Granada, Avda. Ilustración 114 , 18016 Granada , Spain.,R&D Department , NanoGetic SL , Health Science Technological Park (PTS), Avenida de la Innovación 1, Edificio BIC , 18016 Granada , Spain
| | - Victoria Cano-Cortés
- GENYO, Centre for Genomics and Oncological Research , Pfizer/University of Granada/Andalusian Regional Government , PTS Granada, Avda. Ilustración 114 , 18016 Granada , Spain.,Department of Medicinal & Organic Chemistry, Faculty of Pharmacy , University of Granada , Campus de Cartuja s/n , 18071 Granada , Spain
| | - Ana M Pérez-López
- Cancer Research UK Edinburgh Centre, MRC Institute of Genetics & Molecular Medicine , University of Edinburgh , Edinburgh EH4 2XR , United Kingdom
| | - Asier Unciti-Broceta
- Cancer Research UK Edinburgh Centre, MRC Institute of Genetics & Molecular Medicine , University of Edinburgh , Edinburgh EH4 2XR , United Kingdom
| | - Rosario M Sánchez Martín
- GENYO, Centre for Genomics and Oncological Research , Pfizer/University of Granada/Andalusian Regional Government , PTS Granada, Avda. Ilustración 114 , 18016 Granada , Spain.,Department of Medicinal & Organic Chemistry, Faculty of Pharmacy , University of Granada , Campus de Cartuja s/n , 18071 Granada , Spain
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5
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Kwon JA, Jin CM, Shin Y, Kim HY, Kim Y, Kang T, Choi I. Tunable Plasmonic Cavity for Label-free Detection of Small Molecules. ACS APPLIED MATERIALS & INTERFACES 2018; 10:13226-13235. [PMID: 29569438 DOI: 10.1021/acsami.8b01550] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Owing to its high sensitivity and high selectivity along with rapid response time, plasmonic detection has gained considerable interest in a wide variety of sensing applications. To improve the fieldwork applicability and reliability of plasmonic detection, the integration of plasmonic nanoparticles into optical devices is desirable. Herein, we propose an integrated label-free detection platform comprising a plasmonic cavity that allows sensitive molecular detection via either surface-enhanced Raman scattering (SERS) or plasmon resonance energy transfer (PRET). A small droplet of metal ion solution spontaneously produces a plasmonic cavity on the surface of uncured poly(dimethylsiloxane) (PDMS), and as PDMS is cured, the metal ions are reduced to form a plasmonic antennae array on the cavity surface. Unique spherical feature and the integrated metallic nanoparticles of the cavity provide excellent optical functions to focus the incident light in the cavity and to rescatter the light absorbed by the nanoparticles. The optical properties of the plasmonic cavity for SERS or PRET are optimized by controlling the composition, size, and density of the metal nanoparticles. By using the cavity, we accomplish both 1000-fold sensitive detection and real-time monitoring of reactive oxygen species secreted by live cells via PRET. In addition, we achieve sensitive detection of trace amounts of toxic environmental molecules such as 5-chloro-2-methyl-4-isothiazolin-3-one/2-methyl-4-isothiazol-3-one (CMIT/MIT) and bisphenol A, as well as several small biomolecules such as glucose, adenine, and tryptophan, via SERS.
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Affiliation(s)
- Jung A Kwon
- Department of Life Science , University of Seoul , Seoul 130-743 , Republic of Korea
| | - Chang Min Jin
- Department of Life Science , University of Seoul , Seoul 130-743 , Republic of Korea
| | - Yonghee Shin
- Department of Chemical and Biomolecular Engineering , Sogang University , Seoul 121-742 , Republic of Korea
| | - Hye Young Kim
- Department of Life Science , University of Seoul , Seoul 130-743 , Republic of Korea
| | - Yura Kim
- Department of Life Science , University of Seoul , Seoul 130-743 , Republic of Korea
| | - Taewook Kang
- Department of Chemical and Biomolecular Engineering , Sogang University , Seoul 121-742 , Republic of Korea
| | - Inhee Choi
- Department of Life Science , University of Seoul , Seoul 130-743 , Republic of Korea
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6
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Jin CM, Joo JB, Choi I. Facile Amplification of Solution-State Surface-Enhanced Raman Scattering of Small Molecules Using Spontaneously Formed 3D Nanoplasmonic Wells. Anal Chem 2018; 90:5023-5031. [DOI: 10.1021/acs.analchem.7b04674] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Chang Min Jin
- Department of Life Science, University of Seoul, 163 Siripdae-ro, Dongdaemun-gu, Seoul 02504, Republic of Korea
| | - Ji Bong Joo
- Department of Chemical Engineering, Konkuk University, Seoul, 05029, South Korea
| | - Inhee Choi
- Department of Life Science, University of Seoul, 163 Siripdae-ro, Dongdaemun-gu, Seoul 02504, Republic of Korea
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7
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Synthesis of colloidal plasmonic microspheres via spontaneous formation and three-dimensional assembly of metal nanoparticles. KOREAN J CHEM ENG 2017. [DOI: 10.1007/s11814-017-0099-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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8
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Shrirao AB, Kung FH, Yip D, Firestein BL, Cho CH, Townes-Anderson E. A Versatile Method of Patterning Proteins and Cells. J Vis Exp 2017:55513. [PMID: 28287599 PMCID: PMC5409280 DOI: 10.3791/55513] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Substrate and cell patterning techniques are widely used in cell biology to study cell-to-cell and cell-to-substrate interactions. Conventional patterning techniques work well only with simple shapes, small areas and selected bio-materials. This article describes a method to distribute cell suspensions as well as substrate solutions into complex, long, closed (dead-end) polydimethylsiloxane (PDMS) microchannels using negative pressure. This method enables researchers to pattern multiple substrates including fibronectin, collagen, antibodies (Sal-1), poly-D-lysine (PDL), and laminin. Patterning of substrates allows one to indirectly pattern a variety of cells. We have tested C2C12 myoblasts, the PC12 neuronal cell line, embryonic rat cortical neurons, and amphibian retinal neurons. In addition, we demonstrate that this technique can directly pattern fibroblasts in microfluidic channels via brief application of a low vacuum on cell suspensions. The low vacuum does not significantly decrease cell viability as shown by cell viability assays. Modifications are discussed for application of the method to different cell and substrate types. This technique allows researchers to pattern cells and proteins in specific patterns without the need for exotic materials or equipment and can be done in any laboratory with a vacuum.
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Affiliation(s)
- Anil B Shrirao
- Department of Biomedical Engineering, Rutgers University;
| | - Frank H Kung
- Department of Cell Biology and Neuroscience, Rutgers University;
| | - Derek Yip
- Department of Biomedical Engineering, New Jersey Institute of Technology
| | | | - Cheul H Cho
- Department of Biomedical Engineering, New Jersey Institute of Technology
| | - Ellen Townes-Anderson
- Department of Pharmacology, Physiology, and Neuroscience, Rutgers New Jersey Medical School
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9
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Sakamoto S, Okeyo KO, Yamazaki S, Kurosawa O, Oana H, Kotera H, Washizu M. Adhesion patterning by a novel air-lock technique enables localization and in-situ real-time imaging of reprogramming events in one-to-one electrofused hybrids. BIOMICROFLUIDICS 2016; 10:054122. [PMID: 27822330 PMCID: PMC5085977 DOI: 10.1063/1.4965422] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Accepted: 09/01/2016] [Indexed: 05/07/2023]
Abstract
Although fusion of somatic cells with embryonic stem (ES) cells has been shown to induce reprogramming, single-cell level details of the transitory phenotypic changes that occur during fusion-based reprogramming are still lacking. Our group previously reported on the technique of one-to-one electrofusion via micro-slits in a microfluidic platform. In this study, we focused on developing a novel air-lock patterning technique for creating localized adhesion zones around the micro-slits for cell localization and real-time imaging of post fusion events with a single-cell resolution. Mouse embryonic fibroblasts (MEF) were fused individually with mouse ES cells using a polydimethylsiloxane (PDMS) fusion chip consisting of two feeder channels with a separating wall containing an array of micro-slits (slit width ∼3 μm) at a regular spacing. ES cells and MEFs were introduced separately into the channels, juxtaposed on the micro-slits by dielectrophoresis and fused one-to-one by a pulse voltage. To localize fused cells for on-chip culture and time-lapse microscopy, we implemented a two-step approach of air-lock bovine serum albumin patterning and Matrigel coating to create localized adhesion areas around the micro-slits. As a result of time-lapse imaging, we could determine that cell division occurs within 24 h after fusion, much earlier than the 2-3 days reported by earlier studies. Remarkably, Oct4-GFP (Green Fluorescent Protein) was confirmed after 25 h of fusion and thereafter stably expressed by daughter cells of fused cells. Thus, integrated into our high-yield electrofusion platform, the technique of air-lock assisted adhesion patterning enables a single-cell level tracking of fused cells to highlight cell-level dynamics during fusion-based reprogramming.
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Affiliation(s)
- S Sakamoto
- Department of Bioengineering, School of Engineering, The University of Tokyo , Tokyo 113-3656, Japan
| | - K O Okeyo
- Department of Mechanical Engineering, School of Engineering, The University of Tokyo , Tokyo 113-3656, Japan
| | - S Yamazaki
- Center for Stem Cell Therapy, The Institute of Medical Science, The University of Tokyo , Tokyo 113-3656, Japan
| | - O Kurosawa
- Department of Bioengineering, School of Engineering, The University of Tokyo , Tokyo 113-3656, Japan
| | - H Oana
- Department of Mechanical Engineering, School of Engineering, The University of Tokyo , Tokyo 113-3656, Japan
| | - H Kotera
- Department of Microengineering, School of Engineering, Kyoto University , Kyoto 606-8501, Japan
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10
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Choi I, Shin Y, Song J, Hong S, Park Y, Kim D, Kang T, Lee LP. Spontaneous Self-Formation of 3D Plasmonic Optical Structures. ACS NANO 2016; 10:7639-7645. [PMID: 27348191 DOI: 10.1021/acsnano.6b02903] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Self-formation of colloidal oil droplets in water or water droplets in oil not only has been regarded as fascinating fundamental science but also has been utilized in an enormous number of applications in everyday life. However, the creation of three-dimensional (3D) architectures by a liquid droplet and an immiscible liquid interface has been less investigated than other applications. Here, we report interfacial energy-driven spontaneous self-formation of a 3D plasmonic optical structure at room temperature without an external force. Based on the densities and interfacial energies of two liquids, we simulated the spontaneous formation of a plasmonic optical structure when a water droplet containing metal ions meets an immiscible liquid polydimethylsiloxane (PDMS) interface. At the interface, the metal ions in the droplet are automatically reduced to form an interfacial plasmonic layer as the liquid PDMS cures. The self-formation of both an optical cavity and integrated plasmonic nanostructure significantly enhances the fluorescence by a magnitude of 1000. Our findings will have a huge impact on the development of various photonic and plasmonic materials as well as metamaterials and devices.
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Affiliation(s)
- Inhee Choi
- Department of Life Science, University of Seoul , Seoul 130-743, Republic of Korea
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11
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Cong H, Xu X, Yu B, Liu H, Yuan H. Fabrication of universal serial bus flash disk type microfluidic chip electrophoresis and application for protein analysis under ultra low voltage. BIOMICROFLUIDICS 2016; 10:024107. [PMID: 27042249 PMCID: PMC4798985 DOI: 10.1063/1.4943915] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Accepted: 02/29/2016] [Indexed: 06/05/2023]
Abstract
A simple and effective universal serial bus (USB) flash disk type microfluidic chip electrophoresis (MCE) was developed by using poly(dimethylsiloxane) based soft lithography and dry film based printed circuit board etching techniques in this paper. The MCE had a microchannel diameter of 375 μm and an effective length of 25 mm. Equipped with a conventional online electrochemical detector, the device enabled effectively separation of bovine serum albumin, lysozyme, and cytochrome c in 80 s under the ultra low voltage from a computer USB interface. Compared with traditional capillary electrophoresis, the USB flash disk type MCE is not only portable and inexpensive but also fast with high separation efficiency.
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Affiliation(s)
| | - Xiaodan Xu
- College of Materials Science and Engineering, Qingdao University , Qingdao 266071, China
| | | | - Huwei Liu
- Beijing National Laboratory for Molecular Sciences (BNLMS), College of Chemistry and Molecular Engineering, Peking University , Beijing 100871, China
| | - Hua Yuan
- College of Materials Science and Engineering, Qingdao University , Qingdao 266071, China
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12
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A review on recent developments for biomolecule separation at analytical scale using microfluidic devices. Anal Chim Acta 2016; 906:7-21. [DOI: 10.1016/j.aca.2015.11.037] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 11/24/2015] [Accepted: 11/25/2015] [Indexed: 02/05/2023]
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13
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Automated chemiluminescence immunoassay for a nonionic surfactant using a recycled spinning-pausing controlled washing procedure on a compact disc-type microfluidic platform. Talanta 2014; 133:100-6. [PMID: 25435234 DOI: 10.1016/j.talanta.2014.06.075] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Revised: 05/20/2014] [Accepted: 06/13/2014] [Indexed: 11/23/2022]
Abstract
A fully automated and integrated chemiluminescence immunoassay, carried out on a compact disc (CD)-type microfluidic platform, for the detection of alkylphenol polyethoxylates (APnEOs) is described. The pattern of the CD-type microchip was designed so as to permit the sequential solution delivery of the sample solution, the washing solution and the luminol solution, which are required in the chemiluminescence immunoassay process, along with a designed rotation program for spinning the CD-type microchip. The procedure for flowing the washing solution, the volume of which was limited on the CD-type microchip, was optimized by using a recycled spinning-pausing rotation program to overcome the non-specific adsorption of the horseradish peroxidase labeled APnEOs at the detection area. The detection limit of the immunoassay is about 10 ppb.
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14
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de Campos RPS, Yoshida IVP, da Silva JAF. Surface modification of PDMS microchips with poly(ethylene glycol) derivatives for μTAS applications. Electrophoresis 2014; 35:2346-52. [PMID: 24723304 DOI: 10.1002/elps.201300531] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Revised: 03/25/2014] [Accepted: 03/25/2014] [Indexed: 12/19/2022]
Abstract
In this work is presented a method for the modification of native PDMS surface in order to improve its applicability as a substrate for microfluidic devices, especially in the analysis of nonpolar analytes. Therefore, poly(ethylene glycol) divinyl ether modified PDMS substrate was obtained by surface modification of native PDMS. The modified substrate was characterized by attenuated total reflectance infrared spectroscopy, water contact angle measurements, and by evaluating the adsorption of rhodamine B and the magnitude of the EOF mobility. The reaction was confirmed by the spectroscopic evaluation. The formation of a well-spread water film over the surface immediately after the modification was an indicative of the modified surface hydrophilicity. This characteristic was maintained for approximately ten days, with a gradual return to a hydrophobic state. Fluorescence assays showed that the nonpolar adsorption property of PDMS was significantly decreased. The EOF mobility obtained was 3.6 × 10(-4) cm(2) V(-1) s(-1) , higher than the typical values found for native PDMS. Due to the better wettability promoted by the modification, the filling of the microchannels with aqueous solutions was facilitated and trapping of air bubbles was not observed.
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15
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Sierra-Rodero M, Fernández-Romero JM, Gómez-Hens A. Strategies to improve the analytical features of microfluidic methods using nanomaterials. Trends Analyt Chem 2014. [DOI: 10.1016/j.trac.2014.01.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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16
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Surface modification for PDMS-based microfluidic devices. Electrophoresis 2011; 33:89-104. [DOI: 10.1002/elps.201100482] [Citation(s) in RCA: 233] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2011] [Revised: 10/04/2011] [Accepted: 10/04/2011] [Indexed: 11/07/2022]
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