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Lee D, Kim SM, Kim D, Baek SY, Yeo SJ, Lee JJ, Cha C, Park SA, Kim TD. Microfluidics-assisted fabrication of natural killer cell-laden microgel enhances the therapeutic efficacy for tumor immunotherapy. Mater Today Bio 2024; 26:101055. [PMID: 38693995 PMCID: PMC11061753 DOI: 10.1016/j.mtbio.2024.101055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Revised: 03/29/2024] [Accepted: 04/09/2024] [Indexed: 05/03/2024] Open
Abstract
Recently, interest in cancer immunotherapy has increased over traditional anti-cancer therapies such as chemotherapy or targeted therapy. Natural killer (NK) cells are part of the immune cell family and essential to tumor immunotherapy as they detect and kill cancer cells. However, the disadvantage of NK cells is that cell culture is difficult. In this study, porous microgels have been fabricated using microfluidic channels to effectively culture NK cells. Microgel fabrication using microfluidics can be mass-produced in a short time and can be made in a uniform size. Microgels consist of photo cross-linkable polymers such as methacrylic gelatin (GelMa) and can be regulated via controlled GelMa concentrations. NK92 cell-laden three-dimensional (3D) microgels increase mRNA expression levels, NK92 cell proliferation, cytokine release, and anti-tumor efficacy, compared with two-dimensional (2D) cultures. In addition, the study confirms that 3D-cultured NK92 cells enhance anti-tumor effects compared with enhancement by 2D-cultured NK92 cells in the K562 leukemia mouse model. Microgels containing healthy NK cells are designed to completely degrade after 5 days allowing NK cells to be released to achieve cell-to-cell interaction with cancer cells. Overall, this microgel system provides a new cell culture platform for the effective culturing of NK cells and a new strategy for developing immune cell therapy.
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Affiliation(s)
- Dongjin Lee
- Immunotherapy Convergence Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, Republic of Korea
- Nano-Convergence Manufacturing Research Division, Korea Institute of Machinery and Materials (KIMM), Daejeon, 34103, Republic of Korea
| | - Seok Min Kim
- Immunotherapy Convergence Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, Republic of Korea
| | - Dahong Kim
- Nano-Convergence Manufacturing Research Division, Korea Institute of Machinery and Materials (KIMM), Daejeon, 34103, Republic of Korea
- Department of Applied Bioengineering, Seoul National University, Seoul, 08826, Republic of Korea
| | - Seung Yeop Baek
- School of Materials Science and Engineering, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
| | - Seon Ju Yeo
- Nano-Convergence Manufacturing Research Division, Korea Institute of Machinery and Materials (KIMM), Daejeon, 34103, Republic of Korea
| | - Jae Jong Lee
- Nano-Convergence Manufacturing Research Division, Korea Institute of Machinery and Materials (KIMM), Daejeon, 34103, Republic of Korea
| | - Chaenyung Cha
- School of Materials Science and Engineering, Ulsan National Institute of Science and Technology, Ulsan 44919, Republic of Korea
- Department of Biomedical Engineering, School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan, 44919, Republic of Korea
| | - Su A Park
- Nano-Convergence Manufacturing Research Division, Korea Institute of Machinery and Materials (KIMM), Daejeon, 34103, Republic of Korea
| | - Tae-Don Kim
- Immunotherapy Convergence Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 34141, Republic of Korea
- Department of Functional Genomics, KRIBB School of Bioscience, Korea University of Science and Technology (UST), Daejeon, 34113, Republic of Korea
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Choi Y, Song Y, Cho Y, Choi KH, Park C, Lee DG, Lee R, Choi N, Kang JY, Im SG, Seong H. Streamlined Specimen Purification for Rapid COVID-19 Diagnosis Using Positively Charged Polymer Thin Film-Coated Surfaces and Chamber Digital PCR. Anal Chem 2023; 95:14357-14364. [PMID: 37712516 DOI: 10.1021/acs.analchem.3c02716] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/16/2023]
Abstract
The ongoing coronavirus disease 2019 (COVID-19) pandemic demands rapid and straightforward diagnostic tools to prevent early-stage viral transmission. Although nasopharyngeal swabs are a widely used patient sample collection method for diagnosing COVID-19, using these samples for diagnosis without RNA extraction increases the risk of obtaining false-positive and -negative results. Thus, multiple purification steps are necessary, which are time-consuming, generate significant waste, and result in substantial sample loss. To address these issues, we developed surface-modified polymerase chain reaction (PCR) tubes using the tertiary aminated polymer poly(2-dimethylaminomethylstyrene) (pDMAMS) via initiated chemical vapor deposition. Introducing the clinical samples into the pDMAMS-coated tubes resulted in approximately 100% RNA capture efficiency within 25 min, which occurred through electrostatic interactions between the positively charged pDMAMS surface and the negatively charged RNA. The captured RNA is then detected via chamber digital PCR, enabling a sensitive, accurate, and rapid diagnosis. Our platform provides a simple and efficient RNA extraction and detection strategy that allows detection from 22 nasopharyngeal swabs and 21 saliva specimens with 0% false negatives. The proposed method can facilitate the diagnosis of COVID-19 and contribute to the prevention of early-stage transmission.
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Affiliation(s)
- Yunyoung Choi
- Brain Science Institute, Korea Institute of Science and Technology, 5, Hwarang-ro 14-gil, Seongbuk-gu, Seoul 02792, Republic of Korea
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Daejeon 34141, Republic of Korea
| | - Younseong Song
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Daejeon 34141, Republic of Korea
| | - Younghak Cho
- Brain Science Institute, Korea Institute of Science and Technology, 5, Hwarang-ro 14-gil, Seongbuk-gu, Seoul 02792, Republic of Korea
| | - Kyung-Hak Choi
- OPTOLANE Inc., 241, Pangyoyeok-ro, Bundang-gu, Seongnam, Gyeonggi 13494, Republic of Korea
| | - Chulmin Park
- Vaccine Bio Research Institute, The Catholic University of Korea, College of Medicine, 222 Banpo-daero, Seocho-gu, Seoul 06591, Republic of Korea
| | - Dong-Gun Lee
- Vaccine Bio Research Institute, The Catholic University of Korea, College of Medicine, 222 Banpo-daero, Seocho-gu, Seoul 06591, Republic of Korea
| | - Raeseok Lee
- Vaccine Bio Research Institute, The Catholic University of Korea, College of Medicine, 222 Banpo-daero, Seocho-gu, Seoul 06591, Republic of Korea
- Division of Infectious Diseases, Department of Internal Medicine, The Catholic University of Korea, College of Medicine, 222 Banpo-daero, Seocho-gu, Seoul 06591, Republic of Korea
| | - Nakwon Choi
- Brain Science Institute, Korea Institute of Science and Technology, 5, Hwarang-ro 14-gil, Seongbuk-gu, Seoul 02792, Republic of Korea
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Republic of Korea
| | - Ji Yoon Kang
- Brain Science Institute, Korea Institute of Science and Technology, 5, Hwarang-ro 14-gil, Seongbuk-gu, Seoul 02792, Republic of Korea
- Division of Bio-Medical Science and Technology, KIST School, University of Science and Technology (UST), Seoul 02792, Republic of Korea
| | - Sung Gap Im
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Daejeon 34141, Republic of Korea
| | - Hyejeong Seong
- Brain Science Institute, Korea Institute of Science and Technology, 5, Hwarang-ro 14-gil, Seongbuk-gu, Seoul 02792, Republic of Korea
- Division of Bio-Medical Science and Technology, KIST School, University of Science and Technology (UST), Seoul 02792, Republic of Korea
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3
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Cheng Y, Treado JD, Lonial BF, Habdas P, Weeks ER, Shattuck MD, O'Hern CS. Hopper flows of deformable particles. SOFT MATTER 2022; 18:8071-8086. [PMID: 36218162 DOI: 10.1039/d2sm01079h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Numerous experimental and computational studies show that continuous hopper flows of granular materials obey the Beverloo equation that relates the volume flow rate Q and the orifice width w: Q ∼ (w/σavg - k)β, where σavg is the average particle diameter, kσavg is an offset where Q ∼ 0, the power-law scaling exponent β = d - 1/2, and d is the spatial dimension. Recent studies of hopper flows of deformable particles in different background fluids suggest that the particle stiffness and dissipation mechanism can also strongly affect the power-law scaling exponent β. We carry out computational studies of hopper flows of deformable particles with both kinetic friction and background fluid dissipation in two and three dimensions. We show that the exponent β varies continuously with the ratio of the viscous drag to the kinetic friction coefficient, λ = ζ/μ. β = d - 1/2 in the λ → 0 limit and d - 3/2 in the λ → ∞ limit, with a midpoint λc that depends on the hopper opening angle θw. We also characterize the spatial structure of the flows and associate changes in spatial structure of the hopper flows to changes in the exponent β. The offset k increases with particle stiffness until k ∼ kmax in the hard-particle limit, where kmax ∼ 3.5 is larger for λ → ∞ compared to that for λ → 0. Finally, we show that the simulations of hopper flows of deformable particles in the λ → ∞ limit recapitulate the experimental results for quasi-2D hopper flows of oil droplets in water.
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Affiliation(s)
- Yuxuan Cheng
- Department of Physics, Yale University, New Haven, Connecticut, 06520, USA.
| | - John D Treado
- Department of Mechanical Engineering and Materials Science, Yale University, New Haven, Connecticut, 06520, USA
| | | | - Piotr Habdas
- Department of Physics, Saint Joseph's University, Philadelphia, PA 19131, USA
| | - Eric R Weeks
- Department of Physics, Emory University, Atlanta, GA 30322, USA
| | - Mark D Shattuck
- Benjamin Levich Institute and Physics Department, The City College of New York, New York, New York 10031, USA
| | - Corey S O'Hern
- Department of Physics, Yale University, New Haven, Connecticut, 06520, USA.
- Department of Mechanical Engineering and Materials Science, Yale University, New Haven, Connecticut, 06520, USA
- Program in Computational Biology and Bioinformatics, Yale University, New Haven, Connecticut, 06520, USA
- Department of Applied Physics, Yale University, New Haven, Connecticut, 06520, USA.
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Abstract
Microfluidics has enabled a new era of cellular and molecular assays due to the small length scales, parallelization, and the modularity of various analysis and actuation functions. Droplet microfluidics, in particular, has been instrumental in providing new tools for biology with its ability to quickly and reproducibly generate drops that act as individual reactors. A notable beneficiary of this technology has been single-cell RNA sequencing, which has revealed new heterogeneities and interactions for the fundamental unit of life. However, viruses far surpass the diversity of cellular life, affect the dynamics of all ecosystems, and are a chronic source of global health crises. Despite their impact on the world, high-throughput and high-resolution viral profiling has been difficult, with conventional methods being limited to population-level averaging, large sample volumes, and few cultivable hosts. Consequently, most viruses have not been identified and studied. Droplet microfluidics holds the potential to address many of these limitations and offers new levels of sensitivity and throughput for virology. This Feature highlights recent efforts that have applied droplet microfluidics to the detection and study of viruses, including for diagnostics, virus-host interactions, and cell-independent virus assays. In combination with traditional virology methods, droplet microfluidics should prove a potent tool toward achieving a better understanding of the most abundant biological species on Earth.
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Affiliation(s)
- Wenyang Jing
- Center for Biophysics and Quantitative Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Hee-Sun Han
- Center for Biophysics and Quantitative Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States.,Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States.,Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, 1206 West Gregory Drive, Urbana, Illinois 61801, United States
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5
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Onoshima D, Baba Y. Cancer diagnosis and analysis devices based on multimolecular crowding. Chem Commun (Camb) 2021; 57:13655-13661. [PMID: 34854439 DOI: 10.1039/d1cc05556a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The study of the multimolecular crowding around cancer cells has opened up the possibility of developing new devices for cancer diagnosis and analysis through the measurement of intercellular communication related to cell proliferation and invasive metastasis associated with cancer malignancy. In particular, cells and extracellular vesicles that flow into the bloodstream contain metabolites and secreted products of the cancer microenvironment. These are positioned as targets for the development of new devices for the understanding and application of multimolecular crowding around cancer cells. Examples include the separation analysis of cancer cells in blood for the next generation of less invasive testing techniques, and mapping analysis using Raman scattering to detect cancer cells without staining. Another example is the evaluation of the relationship between exosomes and cancer traits for the exploration of new anti-cancer drugs, and the commercialization of exosome separation devices for ultra-early cancer diagnosis. The development of nanobiodevice engineering, which applies multimolecular crowding to conventional nanobioscience, is expected to contribute to the diagnosis and analysis of various diseases in the future.
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Affiliation(s)
- Daisuke Onoshima
- Institute of Nano-Life-Systems, Institutes of Innovation for Future Society, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan.
| | - Yoshinobu Baba
- Institute of Nano-Life-Systems, Institutes of Innovation for Future Society, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan. .,Department of Biomolecular Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan.,Institute of Quantum Life Science, Quantum Life and Medical Science Directorate, National Institutes for Quantum Science and Technology (QST), Anagawa 4-9-1, Inage-ku, Chiba, 263-8555, Japan
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Luo X, Zhou Z, Liu W, Shen D, Yan H, Lin Y, Wan W. Vibrational modes in an optically levitated droplet. OPTICS LETTERS 2021; 46:4602-4605. [PMID: 34525058 DOI: 10.1364/ol.434930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Accepted: 08/23/2021] [Indexed: 06/13/2023]
Abstract
Levitation by optical tweezers provides a unique non-invasive tool for investigating a microscale object without external perturbations. Here we experimentally levitate a micrometer-sized water droplet in the air using an optical tweezer. Meanwhile, vibrational modes of a levitated water droplet are excited by modulating the trapping laser. From their backscattered light, vibrational modes with mode numbers are observed in the spectra. Additionally, their corresponding free spectral ranges are analyzed and compared with theory and numerical simulations. This Letter, establishing a non-invasive and all-optical detection technique of optomechanical properties of levitated droplets, paves the way for their practical applications in aerosol and biomedical science.
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Beshay PE, Ibrahim AM, Jeffrey SS, Howe RT, Anis YH. Encapsulated Cell Dynamics in Droplet Microfluidic Devices with Sheath Flow. MICROMACHINES 2021; 12:mi12070839. [PMID: 34357249 PMCID: PMC8304737 DOI: 10.3390/mi12070839] [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: 07/04/2021] [Revised: 07/15/2021] [Accepted: 07/16/2021] [Indexed: 11/16/2022]
Abstract
In this paper we study the dynamics of single cells encapsulated in water-in-oil emulsions in a microchannel. The flow field of a microfluidic channel is coupled to the internal flow field of a droplet through viscous traction at the interface, resulting in a rotational flow field inside the droplet. An encapsulated single cell being subjected to this flow field responds by undergoing multiple orbits, spins, and deformations that depend on its physical properties. Monitoring the cell dynamics, using a high-speed camera, can lead to the development of new label-free methods for the detection of rare cells, based on their biomechanical properties. A sheath flow microchannel was proposed to strengthen the rotational flow field inside droplets flowing in Poiseuille flow conditions. A numerical model was developed to investigate the effect of various parameters on the rotational flow field inside a droplet. The multi-phase flow model required the tracking of the fluid–fluid interface, which deforms over time due to the applied shear stresses. Experiments confirmed the significant effect of the sheath flow rate on the cell dynamics, where the speed of cell orbiting was doubled. Doubling the cell speed can double the amount of extracted biomechanical information from the encapsulated cell, while it remains within the field of view of the camera used.
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Affiliation(s)
- Peter E. Beshay
- Mechanical Design and Production Department, Faculty of Engineering, Cairo University, Giza 12613, Egypt; (P.E.B.); (A.M.I.)
| | - Ali M. Ibrahim
- Mechanical Design and Production Department, Faculty of Engineering, Cairo University, Giza 12613, Egypt; (P.E.B.); (A.M.I.)
| | - Stefanie S. Jeffrey
- Department of Surgery, Stanford University School of Medicine, Stanford, CA 94305, USA;
| | - Roger T. Howe
- Department of Electrical Engineering, Stanford University, Stanford, CA 94305, USA;
| | - Yasser H. Anis
- Mechanical Design and Production Department, Faculty of Engineering, Cairo University, Giza 12613, Egypt; (P.E.B.); (A.M.I.)
- Correspondence:
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Ibrahim AM, Padovani JI, Howe RT, Anis YH. Modeling of Droplet Generation in a Microfluidic Flow-Focusing Junction for Droplet Size Control. MICROMACHINES 2021; 12:mi12060590. [PMID: 34063839 PMCID: PMC8223991 DOI: 10.3390/mi12060590] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 05/15/2021] [Accepted: 05/19/2021] [Indexed: 01/27/2023]
Abstract
In this paper, we study the parameters that affect the generation of droplets in a microfluidic flow-focusing junction. Droplets are evaluated based on the size and frequency of generation. Droplet size control is essential for microfluidic lab-on-a-chip applications in biology, chemistry, and medicine. We developed a three-dimensional numerical model that can emulate the performance of the physical system. A numerical model can help design droplet-generation chips with new junction geometries, different dispersed and continuous phase types, and different flow rates. Our model uses a conservative level-set method (LSM) to track the interface between two immiscible fluids using a fixed mesh. Water was used for the dispersed phase and mineral oil for the continuous phase. The effects of the continuous-to-dispersed flow rate ratio (Qo/Qw) and the surfactant concentration on the droplet generation were studied both using the numerical model and experimentally. The numerical model was found to render results that are in good agreement with the experimental ones, which validates the LSM model. The validated numerical model was used to study the time effect of changing Qo/Qw on the generated droplet size. Properly timing when the flow rates are changed enables control over the size of the next generated droplet, which is useful for single-droplet size modulation applications.
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Affiliation(s)
- Ali M. Ibrahim
- Mechanical Design and Production Department, Faculty of Engineering, Cairo University, Giza 12613, Egypt;
| | - Jose I. Padovani
- Department of Electrical Engineering, Stanford University, Stanford, CA 94305, USA; (J.I.P.); (R.T.H.)
| | - Roger T. Howe
- Department of Electrical Engineering, Stanford University, Stanford, CA 94305, USA; (J.I.P.); (R.T.H.)
| | - Yasser H. Anis
- Mechanical Design and Production Department, Faculty of Engineering, Cairo University, Giza 12613, Egypt;
- Correspondence:
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Lee D, Shen AQ. Interfacial Tension Measurements in Microfluidic Quasi-Static Extensional Flows. MICROMACHINES 2021; 12:272. [PMID: 33800831 PMCID: PMC8000871 DOI: 10.3390/mi12030272] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 03/03/2021] [Accepted: 03/03/2021] [Indexed: 12/04/2022]
Abstract
Droplet microfluidics provides a versatile tool for measuring interfacial tensions between two immiscible fluids owing to its abilities of fast response, enhanced throughput, portability and easy manipulations of fluid compositions, comparing to conventional techniques. Purely homogeneous extension in the microfluidic device is desirable to measure the interfacial tension because the flow field enables symmetric droplet deformation along the outflow direction. To do so, we designed a microfluidic device consisting of a droplet production region to first generate emulsion droplets at a flow-focusing area. The droplets are then trapped at a stagnation point in the cross junction area, subsequently being stretched along the outflow direction under the extensional flow. These droplets in the device are either confined or unconfined in the channel walls depending on the channel height, which yields different droplet deformations. To calculate the interfacial tension for confined and unconfined droplet cases, quasi-static 2D Darcy approximation model and quasi-static 3D small deformation model are used. For the confined droplet case under the extensional flow, an effective viscosity of the two immiscible fluids, accounting for the viscosity ratio of continuous and dispersed phases, captures the droplet deformation well. However, the 2D model is limited to the case where the droplet is confined in the channel walls and deforms two-dimensionally. For the unconfined droplet case, the 3D model provides more robust estimates than the 2D model. We demonstrate that both 2D and 3D models provide good interfacial tension measurements under quasi-static extensional flows in comparison with the conventional pendant drop method.
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Affiliation(s)
- Doojin Lee
- Department of Polymer Science and Engineering, Chonnam National University, Gwangju 61186, Korea
| | - Amy Q. Shen
- Micro/Bio/Nanofluidics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa 904-0495, Japan
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Development of Microdroplet Generation Method for Organic Solvents Used in Chemical Synthesis. Molecules 2020; 25:molecules25225360. [PMID: 33212771 PMCID: PMC7697074 DOI: 10.3390/molecules25225360] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 11/13/2020] [Accepted: 11/15/2020] [Indexed: 01/09/2023] Open
Abstract
Recently, chemical operations with microfluidic devices, especially droplet-based operations, have attracted considerable attention because they can provide an isolated small-volume reaction field. However, analysis of these operations has been limited mostly to aqueous-phase reactions in water droplets due to device material restrictions. In this study, we have successfully demonstrated droplet formation of five common organic solvents frequently used in chemical synthesis by using a simple silicon/glass-based microfluidic device. When an immiscible liquid with surfactant was used as the continuous phase, the organic solvent formed droplets similar to water-in-oil droplets in the device. In contrast to conventional microfluidic devices composed of resins, which are susceptible to swelling in organic solvents, the developed microfluidic device did not undergo swelling owing to the high chemical resistance of the constituent materials. Therefore, the device has potential applications for various chemical reactions involving organic solvents. Furthermore, this droplet generation device enabled control of droplet size by adjusting the liquid flow rate. The droplet generation method proposed in this work will contribute to the study of organic reactions in microdroplets and will be useful for evaluating scaling effects in various chemical reactions.
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Cai X, Briggs RG, Homburg HB, Young IM, Davis EJ, Lin YH, Battiste JD, Sughrue ME. Application of microfluidic devices for glioblastoma study: current status and future directions. Biomed Microdevices 2020; 22:60. [DOI: 10.1007/s10544-020-00516-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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12
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Abstract
Microfluidic devices developed over the past decade feature greater intricacy, increased performance requirements, new materials, and innovative fabrication methods. Consequentially, new algorithmic and design approaches have been developed to introduce optimization and computer-aided design to microfluidic circuits: from conceptualization to specification, synthesis, realization, and refinement. The field includes the development of new description languages, optimization methods, benchmarks, and integrated design tools. Here, recent advancements are reviewed in the computer-aided design of flow-, droplet-, and paper-based microfluidics. A case study of the design of resistive microfluidic networks is discussed in detail. The review concludes with perspectives on the future of computer-aided microfluidics design, including the introduction of cloud computing, machine learning, new ideation processes, and hybrid optimization.
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Affiliation(s)
- Elishai Ezra Tsur
- Neuro-Biomorphic Engineering Lab (NBEL), Department of Mathematics and Computer Science, The Open University of Israel, Ra'anana 4353701, Israel;
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13
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Sassa F, Biswas GC, Suzuki H. Microfabricated electrochemical sensing devices. LAB ON A CHIP 2020; 20:1358-1389. [PMID: 32129358 DOI: 10.1039/c9lc01112a] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Electrochemistry provides possibilities to realize smart microdevices of the next generation with high functionalities. Electrodes, which constitute major components of electrochemical devices, can be formed by various microfabrication techniques, and integration of the same (or different) components for that purpose is not difficult. Merging this technique with microfluidics can further expand the areas of application of the resultant devices. To augment the development of next generation devices, it will be beneficial to review recent technological trends in this field and clarify the directions required for moving forward. Even when limiting the discussion to electrochemical microdevices, a variety of useful techniques should be considered. Therefore, in this review, we attempted to provide an overview of all relevant techniques in this context in the hope that it can provide useful comprehensive information.
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Affiliation(s)
- Fumihiro Sassa
- Graduate School of Information Science and Electrical Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
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Nguyen TH, Sedighi A, Krull UJ, Ren CL. Multifunctional Droplet Microfluidic Platform for Rapid Immobilization of Oligonucleotides on Semiconductor Quantum Dots. ACS Sens 2020; 5:746-753. [PMID: 32115948 DOI: 10.1021/acssensors.9b02145] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Quantum dot-DNA oligonucleotide (QD-DNA) conjugates have been used in many fields such as nucleic acid bioassays, intracellular probes, and drug delivery systems. A typical solid-phase method that achieves rapid loading of oligonucleotides on surfaces of QDs involves a two-step reaction and is performed in a batch-based approach. In contrast, droplet microfluidics offers many advantages that are unavailable when using batch processing, providing rapid and dense immobilized DNA oligonucleotides on QDs. The presented droplet microfluidic approach allows high-quality QD-DNA conjugates to be produced using one single device, which is designed to have two droplet generators, one droplet merger, and one mixer. One of the droplet generators coencapsulates QDs and magnetic beads (MBs) into nanoliter-sized droplets for the production of QD-MB conjugates and the other encapsulates oligonucleotides in nanoliter-sized droplets. These two streams of droplets then merge at a one-to-one ratio in a chamber. The merged droplets travel along the mixer, which is a serpentine microchannel with 30 turns, resulting in QD-DNA conjugation structures of high quality. This multifunctional microfluidic device provides advantages such as higher degree of control over the reaction conditions, minimized cross-contamination and impurities, and reduction of reagent consumption while eliminating any need for external vortexing and pipetting. To evaluate the quality of the QD-DNA conjugates, they were used as Forster resonance energy transfer (FRET) probes to quantify oligonucleic targets.
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Affiliation(s)
- Thu H. Nguyen
- Department of Mechanical and Mechatronics Engineering, University of Waterloo, 200 University Avenue West, Waterloo N2L3G1, Ontario Canada
| | - Abootaleb Sedighi
- Department of Chemical and Physical Sciences, University of Toronto Mississauga, 3359 Mississauga Road, Mississauga L5L1C6, Ontario, Canada
| | - Ulrich J. Krull
- Department of Chemical and Physical Sciences, University of Toronto Mississauga, 3359 Mississauga Road, Mississauga L5L1C6, Ontario, Canada
| | - Carolyn L. Ren
- Department of Mechanical and Mechatronics Engineering, University of Waterloo, 200 University Avenue West, Waterloo N2L3G1, Ontario Canada
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15
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Zhou Y, Chen Z, Zeng J, Zhang J, Yu D, Zhang B, Yan X, Yang L, Wang Q. Direct Infusion ICP- qMS of Lined-up Single-Cell Using an Oil-Free Passive Microfluidic System. Anal Chem 2020; 92:5286-5293. [PMID: 32181662 DOI: 10.1021/acs.analchem.9b05838] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
When coupled online with mass spectrometry (MS), widely applied water-in-oil droplet-based microfluidics for single cell analysis met problems. For example, the oil phase rumpled the stability, efficiency, and accuracy of MS, the conventional interface between MS and the microfluidic chip suffered the low sample introduction efficiency, and the transportation rates sometimes unmatched the readout dwell times for transient signal acquisition. Considering cells are already "droplets" with hydrophilic surface and elastic hydrophobic membrane, we developed an oil-free passive microfluidic system (OFPMS) that consists of alternating straight-curved-straight microchannels and a direct infusion (dI) micronebulizer for inductively coupled plasma quadrupole-based mass spectrometry (ICP-qMS) of lined-up single-cell. OFPMS guarantees exact single cell isolation one by one just using a thermo-decomposable NH4HCO3 buffer, eliminating the use of any oil and incompatible polymer carriers. It is more flexible and facile to adapt to the dwell time of ICP-qMS owing to the adjustable throughput of 400 to 25000 cells/min and the controllable interval time of at least 20 ms between the lined-up adjacent single cells. Quantitative single-cell transportation and high detection efficiency of more than 70% was realized using OFPMS-dI-ICP-qMS exemplified here. Thus, cell-to-cell heterogeneity can be simply uncovered via the determination of metals in the individual cells.
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16
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Kim S, Ganapathysubramanian B, Anand RK. Concentration Enrichment, Separation, and Cation Exchange in Nanoliter-Scale Water-in-Oil Droplets. J Am Chem Soc 2020; 142:3196-3204. [DOI: 10.1021/jacs.9b13268] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Sungu Kim
- Department of Chemistry, Iowa State University, 1605 Gilman Hall, 2415 Osborn Drive, Ames, Iowa 50011-1021, United States
- Department of Mechanical Engineering, Iowa State University, 2043 Black Engineering, 2529 Union Drive, Ames, Iowa 50011-2030, United States
| | - Baskar Ganapathysubramanian
- Department of Mechanical Engineering, Iowa State University, 2043 Black Engineering, 2529 Union Drive, Ames, Iowa 50011-2030, United States
| | - Robbyn K. Anand
- Department of Chemistry, Iowa State University, 1605 Gilman Hall, 2415 Osborn Drive, Ames, Iowa 50011-1021, United States
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17
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Affiliation(s)
- Malgorzata A. Witek
- Department of Chemistry, The University of Kansas, Lawrence, Kansas 66044, United States
- Center of Biomodular Multiscale Systems for Precision Medicine, The University of Kansas, Lawrence, Kansas 66044, United States
- Department of Biomedical Engineering, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Ian M. Freed
- Department of Chemistry, The University of Kansas, Lawrence, Kansas 66044, United States
- Center of Biomodular Multiscale Systems for Precision Medicine, The University of Kansas, Lawrence, Kansas 66044, United States
| | - Steven A. Soper
- Department of Chemistry, The University of Kansas, Lawrence, Kansas 66044, United States
- Center of Biomodular Multiscale Systems for Precision Medicine, The University of Kansas, Lawrence, Kansas 66044, United States
- Department of Mechanical Engineering, The University of Kansas, Lawrence, Kansas 66044, United States
- Bioengineering Program, The University of Kansas, Lawrence, Kansas 66044, United States
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18
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An Integrated Preprocessing Approach for Exploring Single-Cell Gene Expression in Rare Cells. Sci Rep 2019; 9:19758. [PMID: 31875032 PMCID: PMC6930255 DOI: 10.1038/s41598-019-55831-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 11/25/2019] [Indexed: 02/08/2023] Open
Abstract
Exploring the variability in gene expressions of rare cells at the single-cell level is critical for understanding mechanisms of differentiation in tissue function and development as well as for disease diagnostics and cancer treatment. Such studies, however, have been hindered by major difficulties in tracking the identity of individual cells. We present an approach that combines single-cell picking, lysing, reverse transcription and digital polymerase chain reaction to enable the isolation, tracking and gene expression analysis of rare cells. The approach utilizes a photocleavage bead-based microfluidic device to synthesize and deliver stable cDNA for downstream gene expression analysis, thereby allowing chip-based integration of multiple reactions and facilitating the minimization of sample loss or contamination. The utility of the approach was demonstrated with QuantStudio digital PCR by analyzing the radiation and bystander effect on individual IMR90 human lung fibroblasts. Expression levels of the Cyclin-dependent kinase inhibitor 1a (CDKN1A), Growth/differentiation factor 15 (GDF15), and Prostaglandin-endoperoxide synthase 2 (PTGS2) genes, previously shown to have different responses to direct and bystander irradiation, were measured across individual control, microbeam-irradiated or bystander IMR90 cells. In addition to the confirmation of accurate tracking of cell treatments through the system and efficient analysis of single-cell responses, the results enable comparison of activation levels of different genes and provide insight into signaling pathways within individual cells.
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19
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Bui HK, Seo TS. A micrometer head integrated microfluidic device for facile droplet size control and automatic measurement of a droplet size. Electrophoresis 2019; 41:306-310. [PMID: 31785603 DOI: 10.1002/elps.201900350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 11/20/2019] [Accepted: 11/20/2019] [Indexed: 11/07/2022]
Abstract
A novel microfluidic droplet generator is proposed, which can control the droplet size through turning an integrated micrometer head with ease, and the size of the produced micro-droplet can be automatically and real-time monitored by an open-sourced software and off-the-shelf hardware.
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Affiliation(s)
- Hoang Khang Bui
- Department of Chemical Engineering, College of Engineering, Kyung Hee University, Gyeonggi-do, Republic of Korea
| | - Tae Seok Seo
- Department of Chemical Engineering, College of Engineering, Kyung Hee University, Gyeonggi-do, Republic of Korea
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20
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Grösche M, Korvink JG, Rabe KS, Niemeyer CM. Comparison of Storage Methods for Microfluidically Produced Water‐in‐Oil Droplets. Chem Eng Technol 2019. [DOI: 10.1002/ceat.201900075] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Maximilian Grösche
- Karlsruhe Institute of Technology (KIT)Institute for Biological Interfaces (IBG 1) Hermann-von-Helmholtz-Platz 1 76344 Eggenstein-Leopoldshafen Germany
| | - Jan G. Korvink
- Karlsruhe Institute of Technology (KIT)Institute of Microstructure Technology (IMT) Hermann-von-Helmholtz-Platz 1 76344 Eggenstein-Leopoldshafen Germany
| | - Kersten S. Rabe
- Karlsruhe Institute of Technology (KIT)Institute for Biological Interfaces (IBG 1) Hermann-von-Helmholtz-Platz 1 76344 Eggenstein-Leopoldshafen Germany
| | - Christof M. Niemeyer
- Karlsruhe Institute of Technology (KIT)Institute for Biological Interfaces (IBG 1) Hermann-von-Helmholtz-Platz 1 76344 Eggenstein-Leopoldshafen Germany
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21
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Abstract
Cells are the basic units of life, and can be mimicked to create artificial analogs enabling the investigation of cellular mechanisms under controlled conditions. Building biomimetic systems ranging from proto-cells to cell-like objects such as compartment membranes can be achieved by collecting biobricks that self-assemble to build simplified models performing specific functions. Hence, scientists can develop and optimize new synthetic cells with biological functions by taking inspiration from nature and exploiting the advantages of synthetic biology. However, the bottom-down approach is not restricted to the basic principles of biological cells, and new mimicry systems can be designed starting with a combination of living and non-living simple molecules to focus on a cellular machinery function. In recent years, microfluidic devices have been well established to engineer bioarchitecture models resembling cell-like structures involving vesicles, compartmentalization, synthetic membranes, and the chip itself as a synthetic cell. This review aims to highlight the role of biological cells and their impact on inspiring the development of biomimetic models. The combination of the principles of synthetic biology with microfluidic technology represents the newly-introduced field of synthetic cells and synthetic membranes that can be further exploited in diagnostic and therapeutic applications.
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22
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Fornell A, Johannesson C, Searle SS, Happstadius A, Nilsson J, Tenje M. An acoustofluidic platform for non-contact trapping of cell-laden hydrogel droplets compatible with optical microscopy. BIOMICROFLUIDICS 2019; 13:044101. [PMID: 31312286 PMCID: PMC6624123 DOI: 10.1063/1.5108583] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 06/20/2019] [Indexed: 05/16/2023]
Abstract
Production of cell-laden hydrogel droplets as miniaturized niches for 3D cell culture provides a new route for cell-based assays. Such production can be enabled by droplet microfluidics and here we present a droplet trapping system based on bulk acoustic waves for handling hydrogel droplets in a continuous flow format. The droplet trapping system consists of a glass capillary equipped with a small piezoelectric transducer. By applying ultrasound (4 MHz), a localized acoustic standing wave field is generated in the capillary, trapping the droplets in a well-defined cluster above the transducer area. The results show that the droplet cluster can be retained at flow rates of up to 76 μl/min, corresponding to an average flow speed of 3.2 mm/s. The system allows for important operations such as continuous perfusion and/or addition of chemical reagents to the encapsulated cells with in situ optical access. This feature is demonstrated by performing on-chip staining of the cell nuclei. The key advantages of this trapping method are that it is label-free and gentle and thus well-suited for biological applications. Moreover, the droplets can easily be released on-demand, which facilitates downstream analysis. It is envisioned that the presented droplet trapping system will be a valuable tool for a wide range of multistep assays as well as long-term monitoring of cells encapsulated in gel-based droplets.
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Affiliation(s)
- Anna Fornell
- Department of Engineering Sciences, Science for Life Laboratory, Uppsala University, Box 534, 751 21 Uppsala, Sweden
| | - Carl Johannesson
- Department of Biomedical Engineering, Lund University, Box 118, 221 00 Lund, Sweden
| | | | - Axel Happstadius
- Department of Biomedical Engineering, Lund University, Box 118, 221 00 Lund, Sweden
| | - Johan Nilsson
- Department of Biomedical Engineering, Lund University, Box 118, 221 00 Lund, Sweden
| | - Maria Tenje
- Department of Engineering Sciences, Science for Life Laboratory, Uppsala University, Box 534, 751 21 Uppsala, Sweden
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23
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Steyer DJ, Kennedy RT. High-Throughput Nanoelectrospray Ionization-Mass Spectrometry Analysis of Microfluidic Droplet Samples. Anal Chem 2019; 91:6645-6651. [PMID: 31033282 PMCID: PMC7848793 DOI: 10.1021/acs.analchem.9b00571] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Droplet microfluidics enables high-throughput manipulation of fL-μL volume samples. Methods implemented for the chemical analysis of microfluidic droplets have been limited in scope, leaving some applications of droplet microfluidics difficult to perform or out of reach entirely. Nanoelectrospray ionization-mass spectrometry (nESI-MS) is an attractive approach for droplet analysis, because it allows rapid, label-free, information-rich analysis with high mass sensitivity and resistance to matrix effects. Previous proof-of-concept systems for the nESI-MS analysis of droplets have been limited by the microfluidics used so that stable, long-term operation needed for high-throughput applications has not been demonstrated. We describe a platform for the stable analysis of microfluidic droplet samples by nESI-MS. Continuous infusion of droplets to an nESI emitter was demonstrated for as long as 2.5 h, corresponding to analysis of over 20 000 samples. Stable signal was observed for droplets as small as 65 pL and for throughputs as high as 10 droplets/s. A linear-concentration-based response and sample-to-sample carryover of <3% were also shown. The system is demonstrated for measuring products of in-droplet enzymatic reactions.
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Affiliation(s)
- Daniel J Steyer
- Department of Chemistry , University of Michigan , 930 N. University Avenue , Ann Arbor , Michigan 48109 , United States
| | - Robert T Kennedy
- Department of Chemistry , University of Michigan , 930 N. University Avenue , Ann Arbor , Michigan 48109 , United States
- Department of Pharmacology , University of Michigan , 1150 W. Medical Center Drive , Ann Arbor , Michigan 48109 , United States
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Lashkaripour A, Rodriguez C, Ortiz L, Densmore D. Performance tuning of microfluidic flow-focusing droplet generators. LAB ON A CHIP 2019; 19:1041-1053. [PMID: 30762047 DOI: 10.1039/c8lc01253a] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
The required step in all droplet-based devices is droplet formation. A droplet generator must deliver an application-specific performance that includes a prescribed droplet size and generation frequency while producing monodisperse droplets. The desired performance is usually reached through several cost- and time-inefficient design iterations. To address this, we take advantage of a low-cost rapid prototyping method and provide a framework that enables researchers to make informed decisions on how to change geometric parameters and flow conditions to tune the performance of a microfluidic flow-focusing droplet generator. We present the primary and secondary parameters necessary for fine-tuning droplet formation over a wide range of capillary numbers and flow rate ratios. Once the key parameters are identified, we demonstrate the effect of geometric parameters and flow conditions on droplet size, generation rate, polydispersity, and generation regime. Using this framework, a wide range of droplet diameters (i.e., 30-400 μm) and generation rates (i.e., 0.5-800 Hz) was achieved.
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Affiliation(s)
- Ali Lashkaripour
- Biological Design Center, 610 Commonwealth Avenue, Boston, MA 02215, USA.
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25
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Ahmadi F, Samlali K, Vo PQN, Shih SCC. An integrated droplet-digital microfluidic system for on-demand droplet creation, mixing, incubation, and sorting. LAB ON A CHIP 2019; 19:524-535. [PMID: 30633267 DOI: 10.1039/c8lc01170b] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Droplet microfluidics is a technique that has the ability to compartmentalize reactions in sub nano- (or pico-) liter volumes that can potentially enable millions of distinct biological assays to be performed on individual cells. In a typical droplet microfluidic system, droplets are manipulated by pressure-based flows. This has limited the fluidic operations that can be performed in these devices. Digital microfluidics is an alternative microfluidic paradigm with precise control and manipulation over individual droplets. Here, we implement an integrated droplet-digital microfluidic (which we call 'ID2M') system in which common fluidic operations (i.e. droplet generation, cell encapsulation, droplet merging and mixing, droplet trapping and incubation, and droplet sorting) can be performed. With the addition of electrodes, we have been able to create droplets on-demand, tune their volumes on-demand, and merge and mix several droplets to produce a dilution series. Moreover, this device can trap and incubate droplets for 24 h that can consequently be sorted and analyzed in multiple n-ary channels (as opposed to typical binary channels). The ID2M platform has been validated as a robust on-demand screening system by sorting fluorescein droplets of different concentration with an efficiency of ∼96%. The utility of the new system is further demonstrated by culturing and sorting tolerant yeast mutants and wild-type yeast cells in ionic liquid based on their growth profiles. This new platform for both droplet and digital microfluidics has the potential to be used for screening different conditions on-chip and for applications like directed evolution.
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Affiliation(s)
- Fatemeh Ahmadi
- Department of Electrical and Computer Engineering, Concordia University, Montréal, Québec, Canada.
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26
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Luminescent nanomaterials for droplet tracking in a microfluidic trapping array. Anal Bioanal Chem 2018; 411:157-170. [PMID: 30483856 DOI: 10.1007/s00216-018-1448-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 10/16/2018] [Accepted: 10/22/2018] [Indexed: 12/18/2022]
Abstract
The use of high-throughput multiplexed screening platforms has attracted significant interest in the field of on-site disease detection and diagnostics for their capability to simultaneously interrogate single-cell responses across different populations. However, many of the current approaches are limited by the spectral overlap between tracking materials (e.g., organic dyes) and commonly used fluorophores/biochemical stains, thus restraining their applications in multiplexed studies. This work demonstrates that the downconversion emission spectra offered by rare earth (RE)-doped β-hexagonal NaYF4 nanoparticles (NPs) can be exploited to address this spectral overlap issue. Compared to organic dyes and other tracking materials where the excitation and emission is separated by tens of nanometers, RE elements have a large gap between excitation and emission which results in their spectral independence from the organic dyes. As a proof of concept, two differently doped NaYF4 NPs (europium: Eu3+, and terbium: Tb3+) were employed on a fluorescent microscopy-based droplet microfluidic trapping array to test their feasibility as spectrally independent droplet trackers. The luminescence tracking properties of Eu3+-doped (red emission) and Tb3+-doped (green emission) NPs were successfully characterized by co-encapsulating with genetically modified cancer cell lines expressing green or red fluorescent proteins (GFP and RFP) in addition to a mixed population of live and dead cells stained with ethidium homodimer. Detailed quantification of the luminescent and fluorescent signals was performed to confirm no overlap between each of the NPs and between NPs and cells. Thus, the spectral independence of Eu3+-doped and Tb3+-doped NPs with each other and with common fluorophores highlights the potential application of this novel technique in multiplexed systems, where many such luminescent NPs (other doped and co-doped NPs) can be used to simultaneously track different input conditions on the same platform. Graphical abstract ᅟ.
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27
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The Combined Effects of Co-Culture and Substrate Mechanics on 3D Tumor Spheroid Formation within Microgels Prepared via Flow-Focusing Microfluidic Fabrication. Pharmaceutics 2018; 10:pharmaceutics10040229. [PMID: 30428559 PMCID: PMC6321249 DOI: 10.3390/pharmaceutics10040229] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 11/08/2018] [Accepted: 11/09/2018] [Indexed: 01/23/2023] Open
Abstract
Tumor spheroids are considered a valuable three dimensional (3D) tissue model to study various aspects of tumor physiology for biomedical applications such as tissue engineering and drug screening as well as basic scientific endeavors, as several cell types can efficiently form spheroids by themselves in both suspension and adherent cell cultures. However, it is more desirable to utilize a 3D scaffold with tunable properties to create more physiologically relevant tumor spheroids as well as optimize their formation. In this study, bioactive spherical microgels supporting 3D cell culture are fabricated by a flow-focusing microfluidic device. Uniform-sized aqueous droplets of gel precursor solution dispersed with cells generated by the microfluidic device are photocrosslinked to fabricate cell-laden microgels. Their mechanical properties are controlled by the concentration of gel-forming polymer. Using breast adenocarcinoma cells, MCF-7, the effect of mechanical properties of microgels on their proliferation and the eventual spheroid formation was explored. Furthermore, the tumor cells are co-cultured with macrophages of fibroblasts, which are known to play a prominent role in tumor physiology, within the microgels to explore their role in spheroid formation. Taken together, the results from this study provide the design strategy for creating tumor spheroids utilizing mechanically-tunable microgels as 3D cell culture platform.
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28
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Tone T, Suzuki K. An Automated Liquid Manipulation by Using a Ferrofluid-Based Robotic Sheet. IEEE Robot Autom Lett 2018. [DOI: 10.1109/lra.2018.2842251] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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29
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Li X, Aghaamoo M, Liu S, Lee DH, Lee AP. Lipoplex-Mediated Single-Cell Transfection via Droplet Microfluidics. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2018; 14:e1802055. [PMID: 30199137 DOI: 10.1002/smll.201802055] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 08/09/2018] [Indexed: 06/08/2023]
Abstract
While lipoplex (cationic lipid-nucleic acid complex)-mediated intracellular delivery is widely adopted in mammalian cell transfection, its transfection efficiency for suspension cells, e.g., lymphatic and hematopoietic cells, is reported at only ≈5% or even lower. Here, efficient and consistent lipoplex-mediated transfection is demonstrated for hard-to-transfect suspension cells via a single-cell, droplet-microfluidics approach. In these microdroplets, monodisperse lipoplexes for effective gene delivery are generated via chaotic mixing induced by the serpentine microchannel and co-confined with single cells. Moreover, the cell membrane permeability increases due to the shear stress exerted on the single cells when they pass through the droplet pinch-off junction. The transfection efficiency, examined by the delivery of the pcDNA3-EGFP plasmid, improves from ≈5% to ≈50% for all three tested suspension cell lines, i.e., K562, THP-1, Jurkat, and with significantly reduced cell-to-cell variation, compared to the bulk method. Efficient targeted knockout of the TP53BP1 gene for K562 cells via the CRISPR (clustered regularly interspaced short palindromic repeats)-CAS9 (CRISPR-associated nuclease 9) mechanism is also achieved using this platform. Lipoplex-mediated single-cell transfection via droplet microfluidics is expected to have broad applications in gene therapy and regenerative medicine by providing high transfection efficiency and low cell-to-cell variation for hard-to-transfect suspension cells.
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Affiliation(s)
- Xuan Li
- Department of Biomedical Engineering, University of California, Irvine, Irvine, CA, 92697, USA
| | - Mohammad Aghaamoo
- Department of Biomedical Engineering, University of California, Irvine, Irvine, CA, 92697, USA
| | - Shiyue Liu
- Department of Biochemistry, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Do-Hyun Lee
- Department of Biomedical Engineering, University of California, Irvine, Irvine, CA, 92697, USA
| | - Abraham P Lee
- Department of Biomedical Engineering, University of California, Irvine, Irvine, CA, 92697, USA
- Department of Mechanical and Aerospace Engineering, University of California, Irvine, Irvine, CA, 92697, USA
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30
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Mastiani M, Seo S, Mosavati B, Kim M. High-Throughput Aqueous Two-Phase System Droplet Generation by Oil-Free Passive Microfluidics. ACS OMEGA 2018; 3:9296-9302. [PMID: 31459062 PMCID: PMC6645416 DOI: 10.1021/acsomega.8b01768] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 08/06/2018] [Indexed: 05/29/2023]
Abstract
Aqueous two-phase system (ATPS) droplet generation has significant potential in biological and medical applications because of its excellent biocompatibility. However, the ultralow interfacial tension of ATPS makes droplet generation extremely challenging when compared with the conventional water-in-oil (W/O) system. In this paper, we passively produced ATPS droplets with a wide range of droplet size and high production rate without the involvement of an oil phase and external forces. For the first time, we reported important information of the flow rate and capillary (Ca) number for passive, oil-free ATPS droplet generation. It was found that the range of Ca numbers of the continuous phase under the jetting flow regime is 0.3-1.7, as compared to less than 0.1 in the W/O system, indicating the ultralow interfacial tension in ATPS. In addition, we successfully generated ATPS droplets with a radius as small as 7 μm at the maximum frequency up to 300 Hz, which has not been achieved in previous studies. The size and generation frequency of ATPS droplets can be controlled independently by adjusting the inlet pressures and corresponding flow rates. We found that the droplet size is correlated with the pressure and flow rate ratios with the power-law exponents of 0.8 and 0.2, respectively.
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31
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Dhar P. Thermofluidic Transport in Droplets under Electromagnetic Stimulus: A Comprehensive Review. J Indian Inst Sci 2018. [DOI: 10.1007/s41745-018-0088-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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32
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Song C, Jin T, Yan R, Qi W, Huang T, Ding H, Tan SH, Nguyen NT, Xi L. Opto-acousto-fluidic microscopy for three-dimensional label-free detection of droplets and cells in microchannels. LAB ON A CHIP 2018; 18:1292-1297. [PMID: 29619468 DOI: 10.1039/c8lc00106e] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
This paper reports a novel method, opto-acousto-fluidic microscopy, for label-free detection of droplets and cells in microfluidic networks. Leveraging the optoacoustic effect, the microscopic system possesses capabilities of visualizing flowing droplets, analyzing droplet contents, and detecting cell populations encapsulated in droplets via the sensing of acoustic waves induced by the intrinsic light-absorbance of matter.
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Affiliation(s)
- Chaolong Song
- School of Mechanical Engineering and Electronic Information, China University of Geosciences (Wuhan), Wuhan, China
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33
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Brower K, Puccinelli R, Markin CJ, Shimko TC, Longwell SA, Cruz B, Gomez-Sjoberg R, Fordyce PM. An Open-Source, Programmable Pneumatic Setup for Operation and Automated Control of Single- and Multi-Layer Microfluidic Devices. HARDWAREX 2018; 3:117-134. [PMID: 30221210 PMCID: PMC6136661 DOI: 10.1016/j.ohx.2017.10.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Microfluidic technologies have been used across diverse disciplines (e.g. high-throughput biological measurement, fluid physics, laboratory fluid manipulation) but widespread adoption has been limited in part due to the lack of openly disseminated resources that enable non-specialist labs to make and operate their own devices. Here, we report the open-source build of a pneumatic setup capable of operating both single and multilayer (Quake-style) microfluidic devices with programmable scripting automation. This setup can operate both simple and complex devices with 48 device valve control inputs and 18 sample inputs, with modular design for easy expansion, at a fraction of the cost of similar commercial solutions. We present a detailed step-by-step guide to building the pneumatic instrumentation, as well as instructions for custom device operation using our software, Geppetto, through an easy-to-use GUI for live on-chip valve actuation and a scripting system for experiment automation. We show robust valve actuation with near real-time software feedback and demonstrate use of the setup for high-throughput biochemical measurements on-chip. This open-source setup will enable specialists and novices alike to run microfluidic devices easily in their own laboratories.
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Affiliation(s)
- Kara Brower
- Department of Bioengineering, Stanford University, Stanford CA 94305
- Chem-H Institute, Stanford University, Stanford CA 94305
- Stanford Microfluidic Foundry, Stanford University, Stanford CA 94305
| | | | - Craig J Markin
- Department of Biochemistry, Stanford University, Stanford CA 94305
| | - Tyler C Shimko
- Department of Genetics, Stanford University, Stanford CA 94305
| | - Scott A Longwell
- Department of Bioengineering, Stanford University, Stanford CA 94305
| | - Bianca Cruz
- Department of Physics and Astronomy, California State Polytechnic University Pomona, Pomona CA 91768
| | | | - Polly M Fordyce
- Department of Bioengineering, Stanford University, Stanford CA 94305
- Department of Genetics, Stanford University, Stanford CA 94305
- Chem-H Institute, Stanford University, Stanford CA 94305
- Stanford Microfluidic Foundry, Stanford University, Stanford CA 94305
- Chan Zuckerberg Biohub, San Francisco CA 94158
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34
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Cellular dielectrophoresis coupled with single-cell analysis. Anal Bioanal Chem 2018; 410:2499-2515. [DOI: 10.1007/s00216-018-0896-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 01/11/2018] [Accepted: 01/17/2018] [Indexed: 01/09/2023]
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35
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Katsikis G, Breant A, Rinberg A, Prakash M. Synchronous magnetic control of water droplets in bulk ferrofluid. SOFT MATTER 2018; 14:681-692. [PMID: 29205244 DOI: 10.1039/c7sm01973d] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
We present a microfluidic platform for magnetic manipulation of water droplets immersed in bulk oil-based ferrofluid. Although non-magnetic, the droplets are exclusively controlled by magnetic fields without any pressure-driven flow. The fluids are dispensed in a sub-millimeter Hele-Shaw chamber that includes permalloy tracks on its substrate. An in-plane rotating magnetic field magnetizes the permalloy tracks, producing local magnetic gradients, while an orthogonal magnetic field magnetizes the bulk ferrofluid. To minimize the magnetostatic energy of the system, the water droplets are attracted towards the locations on the tracks where the bulk ferrofluid is repelled. Using this technique, we demonstrate synchronous generation and propagation of water droplets, study the kinematics of propagation, and analyze the flow of the bulk ferrofluid. In addition, we show controlled break-up of droplets and droplet-to-droplet interactions. Finally, we discuss future applications owing to the potential biocompatibility of the droplets.
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Affiliation(s)
- Georgios Katsikis
- Department of Mechanical Engineering, Stanford University, 450 Serra Mall, California 94305, USA
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36
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Park J, Jung JH, Park K, Destgeer G, Ahmed H, Ahmad R, Sung HJ. On-demand acoustic droplet splitting and steering in a disposable microfluidic chip. LAB ON A CHIP 2018; 18:422-432. [PMID: 29220055 DOI: 10.1039/c7lc01083d] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
On-chip droplet splitting is one of the fundamental droplet-based microfluidic unit operations to control droplet volume after production and increase operational capability, flexibility, and throughput. Various droplet splitting methods have been proposed, and among them the acoustic droplet splitting method is promising because of its label-free operation without any physical or thermal damage to droplets. Previous acoustic droplet splitting methods faced several limitations: first, they employed a cross-type acoustofluidic device that precluded multichannel droplet splitting; second, they required irreversible bonding between a piezoelectric substrate and a microfluidic chip, such that the fluidic chip was not replaceable. Here, we present a parallel-type acoustofluidic device with a disposable microfluidic chip to address the limitations of previous acoustic droplet splitting devices. In the proposed device, an acoustic field is applied in the direction opposite to the flow direction to achieve multichannel droplet splitting and steering. A disposable polydimethylsiloxane microfluidic chip is employed in the developed device, thereby removing the need for permanent bonding and improving the flexibility of the droplet microfluidic device. We experimentally demonstrated on-demand acoustic droplet bi-splitting and steering with precise control over the droplet splitting ratio, and we investigated the underlying physical mechanisms of droplet splitting and steering based on Laplace pressure and ray acoustics analyses, respectively. We also demonstrated droplet tri-splitting to prove the feasibility of multichannel droplet splitting. The proposed on-demand acoustic droplet splitting device enables on-chip droplet volume control in various droplet-based microfluidic applications.
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Affiliation(s)
- Jinsoo Park
- Department of Mechanical Engineering, KAIST, Daejeon 34141, Korea.
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37
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Mitsunobu M, Kobayashi S, Takeyasu N, Kaneta T. Temperature-induced Coalescence of Droplets Manipulated by Optical Trapping in an Oil-in-Water Emulsion. ANAL SCI 2018; 33:709-713. [PMID: 28603190 DOI: 10.2116/analsci.33.709] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Coalescence of oil droplets in an oil-in-water (O/W) emulsion was achieved with heating and optical trapping. Three types of O/W emulsions were prepared by adding a mixture of butanol and n-decane to an aqueous solution containing a cationic surfactant (cetyltrimethylammonium bromide, CTAB), an anionic surfactant (sodium dodecyl sulfate, SDS), or a neutral hydrophilic polymer (polyethylene glycol, PEG) as an emulsifier. Two oil droplets in the emulsions were randomly trapped in a square capillary tube by two laser beams in order to induce coalescence. Coalescence of the droplets could not be achieved at room temperature (25°C) regardless of the type of emulsifier. Conversely, the droplets prepared with PEG coalesced at a temperature higher than 30°C, although the droplets with ionic surfactants CTAB and SDS did not coalesce even at the elevated temperature due to their electrostatic repulsion. The size of the resultant coalesced droplet was consistent with that calculated from the size of the two droplets of oil, which indicated successful coalescence of the two droplets. We also found that the time required for the coalescence could be correlated with the temperature using an Arrhenius plot.
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Affiliation(s)
- Manami Mitsunobu
- Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University
| | - Sakurako Kobayashi
- Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University
| | - Nobuyuki Takeyasu
- Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University
| | - Takashi Kaneta
- Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University
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38
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Lee TY, Han K, Barrett DO, Park S, Soper SA, Murphy MC. Accurate, predictable, repeatable micro-assembly technology for polymer, microfluidic modules. SENSORS AND ACTUATORS. B, CHEMICAL 2018. [PMID: 29531428 PMCID: PMC5844477 DOI: 10.1016/j.snb.2017.07.189] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
A method for the design, construction, and assembly of modular, polymer-based, microfluidic devices using simple micro-assembly technology was demonstrated to build an integrated fluidic system consisting of vertically stacked modules for carrying out multi-step molecular assays. As an example of the utility of the modular system, point mutation detection using the ligase detection reaction (LDR) following amplification by the polymerase chain reaction (PCR) was carried out. Fluid interconnects and standoffs ensured that temperatures in the vertically stacked reactors were within ± 0.2 C° at the center of the temperature zones and ± 1.1 C° overall. The vertical spacing between modules was confirmed using finite element models (ANSYS, Inc., Canonsburg, PA) to simulate the steady-state temperature distribution for the assembly. Passive alignment structures, including a hemispherical pin-in-hole, a hemispherical pin-in-slot, and a plate-plate lap joint, were developed using screw theory to enable accurate exactly constrained assembly of the microfluidic reactors, cover sheets, and fluid interconnects to facilitate the modular approach. The mean mismatch between the centers of adjacent through holes was 64 ± 7.7 μm, significantly reducing the dead volume necessary to accommodate manufacturing variation. The microfluidic components were easily assembled by hand and the assembly of several different configurations of microfluidic modules for executing the assay was evaluated. Temperatures were measured in the desired range in each reactor. The biochemical performance was comparable to that obtained with benchtop instruments, but took less than 45 min to execute, half the time.
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Affiliation(s)
- Tae Yoon Lee
- Department of Mechanical & Industrial Engineering, Louisiana State University, Baton Rouge, LA 70803, USA
- Center for Bio-Modular Multi-Scale Systems for Precision Medicine
- Department of Technology Education and Department of Biomedical Engineering, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Kyudong Han
- Department of Nanobiomedical Science & BK21 NBM Global Research Center for Regenerative Medicine, Dankook University, Cheonan 31116, Republic of Korea
| | - Dwhyte O. Barrett
- Department of Mechanical & Industrial Engineering, Louisiana State University, Baton Rouge, LA 70803, USA
- Center for Bio-Modular Multi-Scale Systems for Precision Medicine
| | - Sunggook Park
- Department of Mechanical & Industrial Engineering, Louisiana State University, Baton Rouge, LA 70803, USA
- Center for Bio-Modular Multi-Scale Systems for Precision Medicine
| | - Steven A. Soper
- Department of Mechanical & Industrial Engineering, Louisiana State University, Baton Rouge, LA 70803, USA
- Center for Bio-Modular Multi-Scale Systems for Precision Medicine
- Department of Mechanical Engineering and Department of Chemistry, University of Kansas, Lawrence, KS, USA
| | - Michael C. Murphy
- Department of Mechanical & Industrial Engineering, Louisiana State University, Baton Rouge, LA 70803, USA
- Center for Bio-Modular Multi-Scale Systems for Precision Medicine
- Correspondence: Dr. Michael C. Murphy; , Tel: 1-225-578-5921, Fax: 1-225-578-5924
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39
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Liao S, Tao X, Ju Y, Feng J, Du W, Wang Y. Multichannel Dynamic Interfacial Printing: An Alternative Multicomponent Droplet Generation Technique for Lab in a Drop. ACS APPLIED MATERIALS & INTERFACES 2017; 9:43545-43552. [PMID: 29171252 DOI: 10.1021/acsami.7b16456] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Generation of uniform emulsion droplets mixed with multiple components is one of the key issues in the field of lab in a drop. Traditionally, droplet microfluidic chips are often served as the prime choice while designing and fabricating microfluidic chips always rely on skilled technician and specialized equipment, severely restricting its wide accessibility. In this work, an alternative technique, called multichannel dynamic interfacial printing (MC-DIP), was proposed for multicomponent droplet generation. The MC-DIP device was designed modularly and could be set up manually without any microfabrication process, exhibiting full accessibility for freshmen after a brief training. This new technique owns advantages in the generation of droplets with predictable sizes and composites. Quantitative experiments of measuring minimum inhibitory concentration (MIC) value via mixing microbes and antibiotics into droplet were conducted to proving its application potential for lab in a drop. Further research on a clinical pathogenic strain revealed that this technique could be potentially applied in the clinical laboratory for antibiotic susceptibility testing.
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Affiliation(s)
- Shenglong Liao
- Department of Chemistry, Renmin University of China , Beijing 100872, China
| | - Xinglei Tao
- Department of Chemistry, Renmin University of China , Beijing 100872, China
| | - Yingjiao Ju
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences , Beijing 100101, China
| | - Jie Feng
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences , Beijing 100101, China
| | - Wenbin Du
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences , Beijing 100101, China
| | - Yapei Wang
- Department of Chemistry, Renmin University of China , Beijing 100872, China
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40
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Park K, Park J, Jung JH, Destgeer G, Ahmed H, Sung HJ. In-droplet microparticle separation using travelling surface acoustic wave. BIOMICROFLUIDICS 2017; 11:064112. [PMID: 29308101 PMCID: PMC5739910 DOI: 10.1063/1.5010219] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Accepted: 12/11/2017] [Indexed: 05/05/2023]
Abstract
Droplets in microfluidic systems can contain microscale objects such as cells and microparticles. The control of the positions of microscale objects within a microchannel is crucial for practical applications in not only continuous-flow-based but also droplet-based systems. This paper proposes an active method for the separation of microparticles inside moving droplets which uses travelling surface acoustic waves (TSAWs). We demonstrate the preconcentration and separation of 5 and 10 μm polystyrene microparticles in moving water-in-oil droplets through the application of TSAWs with two different frequencies. The microparticles inside the droplets are affected by the acoustic radiation force induced by the TSAWs to move laterally in the direction of the TSAW propagation and are thereby separated according to their size. In-droplet separation is then demonstrated through droplet splitting at a Y-junction. Compared to our previous studies, this acoustic approach offers the label-free and on-demand separation of different-sized micro-objects in moving droplets. The present method has potential uses such as in-droplet sample purification and enrichment.
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Affiliation(s)
- Kwangseok Park
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, South Korea
| | - Jinsoo Park
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, South Korea
| | - Jin Ho Jung
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, South Korea
| | - Ghulam Destgeer
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, South Korea
| | - Husnain Ahmed
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, South Korea
| | - Hyung Jin Sung
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, South Korea
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41
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Choi YH, Chung KH, Hong HB, Lee WS. Production of PDMS microparticles by emulsification of two phases and their potential biological application. INT J POLYM MATER PO 2017. [DOI: 10.1080/00914037.2017.1375494] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Yo Han Choi
- Electronics and Telecommunications Research Institute, Daejeon, Republic of Korea
| | - Kwang Hyo Chung
- Electronics and Telecommunications Research Institute, Daejeon, Republic of Korea
| | - Hyo Bong Hong
- Electronics and Telecommunications Research Institute, Daejeon, Republic of Korea
| | - Woon Seob Lee
- Memory Manufacturing Operation Center, Samsung Electronics, Suwon, Republic of Korea
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42
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Wiedemeier S, Eichler M, Römer R, Grodrian A, Lemke K, Nagel K, Klages CP, Gastrock G. Parametric studies on droplet generation reproducibility for applications with biological relevant fluids. Eng Life Sci 2017; 17:1271-1280. [PMID: 29399017 PMCID: PMC5765517 DOI: 10.1002/elsc.201700086] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Revised: 08/12/2017] [Accepted: 08/23/2017] [Indexed: 11/08/2022] Open
Abstract
Although the great potential of droplet based microfluidic technologies for routine applications in industry and academia has been successfully demonstrated over the past years, its inherent potential is not fully exploited till now. Especially regarding to the droplet generation reproducibility and stability, two pivotally important parameters for successful applications, there is still a need for improvement. This is even more considerable when droplets are created to investigate tissue fragments or cell cultures (e.g. suspended cells or 3D cell cultures) over days or even weeks. In this study we present microfluidic chips composed of a plasma coated polymer, which allow surfactants-free, highly reproducible and stable droplet generation from fluids like cell culture media. We demonstrate how different microfluidic designs and different flow rates (and flow rate ratios) affect the reproducibility of the droplet generation process and display the applicability for a wide variety of bio(techno)logically relevant media.
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Affiliation(s)
- Stefan Wiedemeier
- Bioprocess Engineering Institute for Bioprocessing and Analytical Measurement Techniques e.V. (iba) Heilbad Heiligenstadt Germany
| | - Marko Eichler
- Atmospheric Pressure Processes Fraunhofer Institute for Surface Engineering and Thin Films (IST) Braunschweig Germany
| | - Robert Römer
- Bioprocess Engineering Institute for Bioprocessing and Analytical Measurement Techniques e.V. (iba) Heilbad Heiligenstadt Germany
| | - Andreas Grodrian
- Bioprocess Engineering Institute for Bioprocessing and Analytical Measurement Techniques e.V. (iba) Heilbad Heiligenstadt Germany
| | - Karen Lemke
- Bioprocess Engineering Institute for Bioprocessing and Analytical Measurement Techniques e.V. (iba) Heilbad Heiligenstadt Germany
| | - Krees Nagel
- Atmospheric Pressure Processes Fraunhofer Institute for Surface Engineering and Thin Films (IST) Braunschweig Germany
| | - Claus-Peter Klages
- Atmospheric Pressure Processes Fraunhofer Institute for Surface Engineering and Thin Films (IST) Braunschweig Germany
| | - Gunter Gastrock
- Bioprocess Engineering Institute for Bioprocessing and Analytical Measurement Techniques e.V. (iba) Heilbad Heiligenstadt Germany
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43
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Rinberg A, Katsikis G, Prakash M. Generation of droplet arrays with rational number spacing patterns driven by a periodic energy landscape. Phys Rev E 2017; 96:033108. [PMID: 29346989 DOI: 10.1103/physreve.96.033108] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Indexed: 06/07/2023]
Abstract
The generation of droplets at low Reynolds numbers is driven by nonlinear dynamics that give rise to complex patterns concerning both the droplet-to-droplet spacing and the individual droplet sizes. Here we demonstrate an experimental system in which a time-varying energy landscape provides a periodic magnetic force that generates an array of droplets from an immiscible mixture of ferrofluid and silicone oil. The resulting droplet patterns are periodic, owing to the nature of the magnetic force, yet the droplet spacing and size can vary greatly by tuning a single bias pressure applied on the ferrofluid phase; for a given cycle period of the magnetic force, droplets can be generated either at integer multiples (1, 2, ...), or at rational fractions (3/2, 5/3, 5/2, ...) of this period with mono- or multidisperse droplet sizes. We develop a discrete-time dynamical systems model not only to reproduce the phenotypes of the observed patterns but also to provide a framework for understanding systems driven by such periodic energy landscapes.
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Affiliation(s)
- Anatoly Rinberg
- School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA
| | - Georgios Katsikis
- Department of Mechanical Engineering, Stanford University, Stanford, California 94305, USA
| | - Manu Prakash
- Department of Bioengineering, Stanford University, Stanford, California 94305, USA
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44
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Chen H, Man J, Li Z, Li J. Microfluidic Generation of High-Viscosity Droplets by Surface-Controlled Breakup of Segment Flow. ACS APPLIED MATERIALS & INTERFACES 2017; 9:21059-21064. [PMID: 28589716 DOI: 10.1021/acsami.7b03438] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Fluids containing high concentration polymers, sols, nanoparticles, etc., usually have high viscosities, and high-viscosity fluids are difficult to be encapsulated into uniform droplets. Here we report a surface-controlled breakup method to generate droplets directly from various aqueous and nonaqueous fluids with viscosities of 1.0 to 11.9 Pa s and a dispersed-to-continuous viscosity ratio up to 1000, whereas the volume fraction of droplets up to 50% can be achieved. It provides a straightforward method to encapsulate high viscosity fluids, in a well-controlled manner in the rapid developing droplet-based applications, including materials synthesis, drug delivery, cell assay, bioengineering, etc.
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Affiliation(s)
- Haosheng Chen
- State Key Laboratory of Tribology, Tsinghua University , Beijing 100084, China
| | - Jia Man
- State Key Laboratory of Tribology, Tsinghua University , Beijing 100084, China
| | - Zhongnan Li
- State Key Laboratory of Tribology, Tsinghua University , Beijing 100084, China
| | - Jiang Li
- School of Mechanical Engineering, University of Science and Technology Beijing , Beijing 100083, China
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45
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Liu Y, Lu H. Microfluidics in systems biology-hype or truly useful? Curr Opin Biotechnol 2017; 39:215-220. [PMID: 27267565 DOI: 10.1016/j.copbio.2016.04.020] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Revised: 04/20/2016] [Accepted: 04/21/2016] [Indexed: 12/13/2022]
Abstract
Systems biology often relies on large-scale measurements and model-building to understand how complex biological systems function. Microfluidic technology has been touted as a tool for high-throughput experiments and has been a valuable tool to some systems biology research. This review focuses on applications where microfluidics can enhance experimental sensitivity and throughput, particularly in recent development in single-cell analyses and analyses on multi-cellular or complex biological entities. We conclude that microfluidics is not necessarily always useful for systems biology, but when used appropriately can greatly enhance experimentalists' ability to measure and control, and thereby enhance the understanding of and expand the utility of biological systems.
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Affiliation(s)
- Yi Liu
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0100, United States
| | - Hang Lu
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0100, United States.
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46
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Lin G, Makarov D, Schmidt OG. Magnetic sensing platform technologies for biomedical applications. LAB ON A CHIP 2017; 17:1884-1912. [PMID: 28485417 DOI: 10.1039/c7lc00026j] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Detection and quantification of a variety of micro- and nanoscale entities, e.g. molecules, cells, and particles, are crucial components of modern biomedical research, in which biosensing platform technologies play a vital role. Confronted with the drastic global demographic changes, future biomedical research entails continuous development of new-generation biosensing platforms targeting even lower costs, more compactness, and higher throughput, sensitivity and selectivity. Among a wide choice of fundamental biosensing principles, magnetic sensing technologies enabled by magnetic field sensors and magnetic particles offer attractive advantages. The key features of a magnetic sensing format include the use of commercially available magnetic field sensing elements, e.g. magnetoresistive sensors which bear huge potential for compact integration, a magnetic field sensing mechanism which is free from interference by complex biomedical samples, and an additional degree of freedom for the on-chip handling of biochemical species rendered by magnetic labels. In this review, we highlight the historical basis, routes, recent advances and applications of magnetic biosensing platform technologies based on magnetoresistive sensors.
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Affiliation(s)
- Gungun Lin
- Institute for Integrative Nanosciences, IFW Dresden, Helmholzstr. 20, 01069, Dresden, Germany
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47
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Abstract
Droplet microfluidics generates and manipulates discrete droplets through immiscible multiphase flows inside microchannels. Due to its remarkable advantages, droplet microfluidics bears significant value in an extremely wide range of area. In this review, we provide a comprehensive and in-depth insight into droplet microfluidics, covering fundamental research from microfluidic chip fabrication and droplet generation to the applications of droplets in bio(chemical) analysis and materials generation. The purpose of this review is to convey the fundamentals of droplet microfluidics, a critical analysis on its current status and challenges, and opinions on its future development. We believe this review will promote communications among biology, chemistry, physics, and materials science.
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Affiliation(s)
- Luoran Shang
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University , Nanjing 210096, China
| | - Yao Cheng
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University , Nanjing 210096, China
| | - Yuanjin Zhao
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University , Nanjing 210096, China
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48
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Fornell A, Ohlin M, Garofalo F, Nilsson J, Tenje M. An intra-droplet particle switch for droplet microfluidics using bulk acoustic waves. BIOMICROFLUIDICS 2017; 11:031101. [PMID: 28580044 PMCID: PMC5446280 DOI: 10.1063/1.4984131] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Accepted: 05/13/2017] [Indexed: 05/18/2023]
Abstract
To transfer cell- and bead-assays into droplet-based platforms typically requires the use of complex microfluidic circuits, which calls for methods to switch the direction of the encapsulated particles. We present a microfluidic chip where the combination of acoustic manipulation at two different harmonics and a trident-shaped droplet-splitter enables direction-switching of microbeads and yeast cells in droplet microfluidic circuits. At the first harmonic, the encapsulated particles exit the splitter in the center daughter droplets, while at the second harmonic, the particles exit in the side daughter droplets. This method holds promises for droplet-based assays where particle-positioning needs to be selectively controlled.
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Affiliation(s)
- Anna Fornell
- Department Biomedical Engineering, Lund University, Lund, Sweden
| | - Mathias Ohlin
- Department Engineering Sciences, Uppsala University, Uppsala, Sweden
| | - Fabio Garofalo
- Department Biomedical Engineering, Lund University, Lund, Sweden
| | - Johan Nilsson
- Department Biomedical Engineering, Lund University, Lund, Sweden
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49
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Shen F, Li Y, Liu Z, Li X. Study of flow behaviors of droplet merging and splitting in microchannels using Micro-PIV measurement. MICROFLUIDICS AND NANOFLUIDICS 2017; 21:66. [PMID: 28890680 PMCID: PMC5589143 DOI: 10.1007/s10404-017-1902-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Droplet merging and splitting are important droplet manipulations in droplet-based microfluidics. However, the fundamental flow behaviors of droplets were not systematically studied. Hence, we designed two different microstructures to achieve droplet merging and splitting respectively, and quantitatively compared different flow dynamics in different microstructures for droplet merging and splitting via micro-particle image velocimetry (micro-PIV) experiments. Some flow phenomena of droplets different from previous studies were observed during merging and splitting using a high-speed microscope. It was also found the obtained instantaneous velocity vector fields of droplets have significant influence on the droplets merging and splitting. For droplet merging, the probability of droplets coalescence (η) in a microgroove is higher (50% < η < 92%) than that in a T-junction microchannel (15% < η < 50%), and the highest coalescence efficiency (η = 92%) comes at the two-phase flow ratio e of 0.42 in the microgroove. Moreover, compared with a cylinder obstacle, Y-junction bifurcation can split droplets more effectively and the droplet flow during splitting is steadier. The results can provide better understanding of droplet behaviors and are useful for the design and applications of droplet-based microfluidics.
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Affiliation(s)
- Feng Shen
- College of Mechanical Engineering and Applied Electronics Technology, Beijing University of Technology, Beijing 100124, China
| | - Yi Li
- College of Mechanical Engineering and Applied Electronics Technology, Beijing University of Technology, Beijing 100124, China
| | - Zhaomiao Liu
- College of Mechanical Engineering and Applied Electronics Technology, Beijing University of Technology, Beijing 100124, China
| | - XiuJun Li
- Department of Chemistry, University of Texas at El Paso, El Paso, TX 79968, USA
- Border Biomedical Research Center, University of Texas at El Paso, El Paso, TX 79968, USA
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50
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Dong J, Ueda H. ELISA-type assays of trace biomarkers using microfluidic methods. WILEY INTERDISCIPLINARY REVIEWS-NANOMEDICINE AND NANOBIOTECHNOLOGY 2017; 9. [DOI: 10.1002/wnan.1457] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 11/15/2016] [Accepted: 12/17/2016] [Indexed: 11/05/2022]
Affiliation(s)
- Jinhua Dong
- Shandong Provincial Key Laboratory of Detection Technology for Tumor Markers; College of Chemistry and Chemical Engineering, Linyi University; Linyi P.R. China
- Laboratory for Chemistry and Life Science, Institute of Innovative Research; Tokyo Institute of Technology; Yokohama Japan
| | - Hiroshi Ueda
- Laboratory for Chemistry and Life Science, Institute of Innovative Research; Tokyo Institute of Technology; Yokohama Japan
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