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Seo S, Kim T. Gas transport mechanisms through gas-permeable membranes in microfluidics: A perspective. BIOMICROFLUIDICS 2023; 17:061301. [PMID: 38025658 PMCID: PMC10656118 DOI: 10.1063/5.0169555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Accepted: 10/30/2023] [Indexed: 12/01/2023]
Abstract
Gas-permeable membranes (GPMs) and membrane-like micro-/nanostructures offer precise control over the transport of liquids, gases, and small molecules on microchips, which has led to the possibility of diverse applications, such as gas sensors, solution concentrators, and mixture separators. With the escalating demand for GPMs in microfluidics, this Perspective article aims to comprehensively categorize the transport mechanisms of gases through GPMs based on the penetrant type and the transport direction. We also provide a comprehensive review of recent advancements in GPM-integrated microfluidic devices, provide an overview of the fundamental mechanisms underlying gas transport through GPMs, and present future perspectives on the integration of GPMs in microfluidics. Furthermore, we address the current challenges associated with GPMs and GPM-integrated microfluidic devices, taking into consideration the intrinsic material properties and capabilities of GPMs. By tackling these challenges head-on, we believe that our perspectives can catalyze innovative advancements and help meet the evolving demands of microfluidic applications.
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Affiliation(s)
- Sangjin Seo
- Department of Mechanical Engineering, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Ulsan 44919, Republic of Korea
| | - Taesung Kim
- Author to whom correspondence should be addressed:. Tel.: +82-52-217-2313. Fax: +82-52-217-2409
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Zhang C, Zhang X, Li Q, Wu L. Numerical Study of Bubble Breakup in Fractal Tree-Shaped Microchannels. Int J Mol Sci 2019; 20:ijms20215516. [PMID: 31694334 PMCID: PMC6862512 DOI: 10.3390/ijms20215516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 10/30/2019] [Accepted: 11/04/2019] [Indexed: 11/16/2022] Open
Abstract
Hydrodynamic behaviors of bubble stream flow in fractal tree-shaped microchannels is investigated numerically based on a two-dimensional volume of fluid (VOF) method. Bubble breakup is examined in each level of bifurcation and the transition of breakup regimes is discussed in particular. The pressure variations at the center of different levels of bifurcations are analyzed in an effort to gain further insight into the underlying mechanism of bubble breakup affected by multi-levels of bifurcations in tree-shaped microchannel. The results indicate that due to the structure of the fractal tree-shaped microchannel, both lengths of bubbles and local capillary numbers decrease along the microchannel under a constant inlet capillary number. Hence the transition from the obstructed breakup and obstructed-tunnel combined breakup to coalescence breakup is observed when the bubbles are flowing into a higher level of bifurcations. Compared with the breakup of the bubbles in the higher level of bifurcations, the behaviors of bubbles show stronger periodicity in the lower level of bifurcations. Perturbations grow and magnify along the flow direction and the flow field becomes more chaotic at higher level of bifurcations. Besides, the feedback from the unequal downstream pressure to the upstream lower level of bifurcations affects the bubble breakup and enhances the upstream asymmetrical behaviors.
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Affiliation(s)
- Chengbin Zhang
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing, Jiangsu 210096, China; (C.Z.); (X.Z.); (Q.L.)
| | - Xuan Zhang
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing, Jiangsu 210096, China; (C.Z.); (X.Z.); (Q.L.)
| | - Qianwen Li
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing, Jiangsu 210096, China; (C.Z.); (X.Z.); (Q.L.)
| | - Liangyu Wu
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing, Jiangsu 210096, China; (C.Z.); (X.Z.); (Q.L.)
- College of Electrical, Energy and Power Engineering, Yangzhou University, Yangzhou 225127, China
- Correspondence: ; Tel.: +86-25-8379-2483
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Shin S, Shardt O, Warren PB, Stone HA. Membraneless water filtration using CO 2. Nat Commun 2017; 8:15181. [PMID: 28462929 PMCID: PMC5418569 DOI: 10.1038/ncomms15181] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Accepted: 03/07/2017] [Indexed: 11/13/2022] Open
Abstract
Water purification technologies such as microfiltration/ultrafiltration and reverse osmosis utilize porous membranes to remove suspended particles and solutes. These membranes, however, cause many drawbacks such as a high pumping cost and a need for periodic replacement due to fouling. Here we show an alternative membraneless method for separating suspended particles by exposing the colloidal suspension to CO2. Dissolution of CO2 into the suspension creates solute gradients that drive phoretic motion of particles. Due to the large diffusion potential generated by the dissociation of carbonic acid, colloidal particles move either away from or towards the gas–liquid interface depending on their surface charge. Using the directed motion of particles induced by exposure to CO2, we demonstrate a scalable, continuous flow, membraneless particle filtration process that exhibits low energy consumption, three orders of magnitude lower than conventional microfiltration/ultrafiltration processes, and is essentially free from fouling. Water treatment processes mostly rely on the use of membranes and filters, which have high pumping costs and require periodic replacement. Here, the authors describe an efficient membraneless method that induces directed motion of suspended colloidal particles by exposing the suspension to CO2.
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Affiliation(s)
- Sangwoo Shin
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544, USA
| | - Orest Shardt
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544, USA
| | | | - Howard A Stone
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544, USA
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Femmer T, Eggersdorfer ML, Kuehne AJC, Wessling M. Efficient gas-liquid contact using microfluidic membrane devices with staggered herringbone mixers. LAB ON A CHIP 2015; 15:3132-3137. [PMID: 26087992 DOI: 10.1039/c5lc00428d] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We describe a novel membrane based gas-liquid-contacting device with increased mass transport and reduced pressure loss by combining a membrane with a staggered herringbone static mixer. Herringbone structures are imposed on the microfluidic channel geometry via soft lithography, acting as mixers which introduce secondary flows at the membrane interface. Such flows include Dean vortices and Taylor flows generating effective mixing while improving mass transport and preventing concentration polarization in microfluidic channels. Furthermore, our static herringbone mixer membranes effectively reduce pressure losses leading to devices with enhanced transfer properties for microfluidic gas-liquid contact. We investigate the red blood cell distribution to tailor our devices towards miniaturised extracorporeal membrane oxygenation and improved comfort of patients with lung insufficiencies.
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Affiliation(s)
- Tim Femmer
- Chemical Process Engineering, RWTH Aachen University, Turmstraße 46, 52064 Aachen, Germany.
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Hsu WL, Inglis DW, Jeong H, Dunstan DE, Davidson MR, Goldys EM, Harvie DJE. Stationary chemical gradients for concentration gradient-based separation and focusing in nanofluidic channels. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:5337-5348. [PMID: 24725102 DOI: 10.1021/la500206b] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Previous work has demonstrated the simultaneous concentration and separation of proteins via a stable ion concentration gradient established within a nanochannel (Inglis Angew. Chem., Int. Ed. 2001, 50, 7546-7550). To gain a better understanding of how this novel technique works, we here examine experimentally and numerically how the underlying electric potential controlled ion concentration gradients can be formed and controlled. Four nanochannel geometries are considered. Measured fluorescence profiles, a direct indicator of ion concentrations within the Tris-fluorescein buffer solution, closely match depth-averaged fluorescence profiles calculated from the simulations. The simulations include multiple reacting species within the fluid bulk and surface wall charge regulation whereby the deprotonation of silica-bound silanol groups is governed by the local pH. The three-dimensional system is simulated in two dimensions by averaging the governing equations across the (varying) nanochannel width, allowing accurate numerical results to be generated for the computationally challenging high aspect ratio nanochannel geometries. An electrokinetic circuit analysis is incorporated to directly relate the potential drop across the (simulated) nanochannel to that applied across the experimental chip device (which includes serially connected microchannels). The merit of the thick double layer, potential-controlled concentration gradient as a particle focusing and separation tool is discussed, linking this work to the previously presented protein trapping experiments. We explain why stable traps are formed when the flow is in the opposite direction to the concentration gradient, allowing particle separation near the low concentration end of the nanochannel. We predict that tapered, rather than straight nanochannels are better at separating particles of different electrophoretic mobilities.
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Affiliation(s)
- Wei-Lun Hsu
- Department of Chemical and Biomolecular Engineering, University of Melbourne , Victoria 3010, Australia
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Rahman MT, Krishnamurthy PG, Parthiban P, Jain A, Park CP, Kim DP, Khan SA. Dynamically tunable nanoparticle engineering enabled by short contact-time microfluidic synthesis with a reactive gas. RSC Adv 2013. [DOI: 10.1039/c2ra23216b] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
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Karatay E, Lammertink RGH. Oxygenation by a superhydrophobic slip G/L contactor. LAB ON A CHIP 2012; 12:2922-9. [PMID: 22722560 DOI: 10.1039/c2lc21296j] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The compelling need for an efficient supply of gases into liquids or degassing of fluids within confined microchannels triggered our study on membrane assisted microchemical systems. Porous hydrophobic flat/micro-structured polyvinylidene fluoride (PVDF) membranes were fabricated and integrated in a glass G/L contacting microfluidic device with the aid of optical adhesives. The oxygen transport in microchannels, driven by convection and diffusion, was investigated both experimentally and numerically. The effects of intrinsic membrane morphology on the G/L contacting performance of the resultant membranes were studied. The experimental performance of the flat membranes are shown to obey the simulation results with the assumptions of negligible gas phase and membrane mass transfer limitations. Micro-structured membranes revealed apparent slippage and enhanced mass transport rates, and exceeded the experimental performance of the flat membranes.
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Affiliation(s)
- Elif Karatay
- University of Twente, Soft Matter, Fluidics and Interfaces, MESA+ Institute for Nanotechnology, Drienerlolaan 5, 7500AE, Enschede, The Netherlands
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Forry SP, Locascio LE. On-chip CO2 control for microfluidic cell culture. LAB ON A CHIP 2011; 11:4041-4046. [PMID: 21996787 DOI: 10.1039/c1lc20505f] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Carbon dioxide partial pressure (P(CO(2))) was controlled on-chip by flowing pre-equilibrated aqueous solutions through control channels across the device. Elevated P(CO(2)) (e.g. 0.05 atm) was modulated in neighboring stagnant channels via equilibration through the highly gas permeable substrate, poly(dimethylsiloxane) (PDMS). Stable gradients in P(CO(2)) were demonstrated with a pair of control lines in a source-sink configuration. P(CO(2)) equilibration was found to be sufficiently rapid (minutes) and stable (days) to enable long-term microfluidic culture of mammalian cells. The aqueous solutions flowing through the device also mitigated pervaporative losses at sustained elevated temperatures (e.g. 37 C), as compared to flowing humidified gas through the control lines to control P(CO(2)). Since pervaporation (and the associated increase in osmolality) was minimized, stopped-flow cell culture became possible, wherein cell secretions can accumulate within the confined environment of the microfluidic culture system. This strategy was utilized to demonstrate long-term (> 7 days) microfluidic culture of mouse fibroblasts under stopped-flow conditions without requiring the microfluidic system to be placed inside a cell culture incubator.
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Affiliation(s)
- Samuel P Forry
- Biochemical Sciences Division, Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899-6312, USA.
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Park CP, Maurya RA, Lee JH, Kim DP. Efficient photosensitized oxygenations in phase contact enhanced microreactors. LAB ON A CHIP 2011; 11:1941-1945. [PMID: 21499614 DOI: 10.1039/c1lc20071b] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A transparent dual-channel microreactor with highly enhanced contact area-to-volume ratio was fabricated for efficient photosensitized oxygenations. The dual-channel microreactor shielded with polyvinylsilazane (PVSZ) consisting of an upper channel for liquid flow and a lower channel for O(2) flow, allows sufficient phase contact along the parallel channels through a gas permeable PDMS membrane for maintaining the O(2) saturated solution. Under full exposure of reactants to light, the reactions in high concentration are completed in minutes rather than hours that it takes to complete in a batch reactor. Moreover, the scale-up process using the microreactor revealed higher productivity than the batch reactor, which would be valuable for the practical applications in a broad range of gas-liquid chemical reactions.
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Affiliation(s)
- Chan Pil Park
- National Creative Research Center of Applied Microfluidic Chemistry, Chungnam National University, Daejeon, South Korea
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Yuen PK, Su H, Goral VN, Fink KA. Three-dimensional interconnected microporous poly(dimethylsiloxane) microfluidic devices. LAB ON A CHIP 2011; 11:1541-4. [PMID: 21359315 DOI: 10.1039/c0lc00660b] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
This technical note presents a fabrication method and applications of three-dimensional (3D) interconnected microporous poly(dimethylsiloxane) (PDMS) microfluidic devices. Based on soft lithography, the microporous PDMS microfluidic devices were fabricated by molding a mixture of PDMS pre-polymer and sugar particles in a microstructured mold. After curing and demolding, the sugar particles were dissolved and washed away from the microstructured PDMS replica revealing 3D interconnected microporous structures. Other than introducing microporous structures into the PDMS replica, different sizes of sugar particles can be used to alter the surface wettability of the microporous PDMS replica. Oxygen plasma assisted bonding was used to enclose the microstructured microporous PDMS replica using a non-porous PDMS with inlet and outlet holes. A gas absorption reaction using carbon dioxide (CO(2)) gas acidified water was used to demonstrate the advantages and potential applications of the microporous PDMS microfluidic devices. We demonstrated that the acidification rate in the microporous PDMS microfluidic device was approximately 10 times faster than the non-porous PDMS microfluidic device under similar experimental conditions. The microporous PDMS microfluidic devices can also be used in cell culture applications where gas perfusion can improve cell survival and functions.
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Affiliation(s)
- Po Ki Yuen
- Science & Technology, Corning Incorporated, Corning, New York 14831-0001, USA.
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Affiliation(s)
- Chan Pil Park
- National Creative Research Center of Applied Microfluidic Chemistry, and Graduate School of Analytical Science and Technology, Chungnam National University, Daejeon, 305-764, South Korea
| | - Dong-Pyo Kim
- National Creative Research Center of Applied Microfluidic Chemistry, and Graduate School of Analytical Science and Technology, Chungnam National University, Daejeon, 305-764, South Korea
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Arora A, Simone G, Salieb-Beugelaar GB, Kim JT, Manz A. Latest Developments in Micro Total Analysis Systems. Anal Chem 2010; 82:4830-47. [PMID: 20462185 DOI: 10.1021/ac100969k] [Citation(s) in RCA: 372] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Arun Arora
- KIST Europe, Korea Institute of Science and Technology, Campus E71, 66123 Saarbrücken, Germany, FRIAS, Freiburg Institute for Advanced Studies, Albert-Ludwigs-Universität Freiburg, Albertstrasse 19, 79104 Freiburg, Germany, IMTEK, Institute for Microsystem Technology, University of Freiburg, Georges-Köhler-Allee 103, 79110 Freiburg, Germany, and MESA+ Institute for Nanotechnology/Lab-on-a-Chip Group, Twente University, Building Carré, 7500 AE, Enschede, The Netherlands
| | - Giuseppina Simone
- KIST Europe, Korea Institute of Science and Technology, Campus E71, 66123 Saarbrücken, Germany, FRIAS, Freiburg Institute for Advanced Studies, Albert-Ludwigs-Universität Freiburg, Albertstrasse 19, 79104 Freiburg, Germany, IMTEK, Institute for Microsystem Technology, University of Freiburg, Georges-Köhler-Allee 103, 79110 Freiburg, Germany, and MESA+ Institute for Nanotechnology/Lab-on-a-Chip Group, Twente University, Building Carré, 7500 AE, Enschede, The Netherlands
| | - Georgette B. Salieb-Beugelaar
- KIST Europe, Korea Institute of Science and Technology, Campus E71, 66123 Saarbrücken, Germany, FRIAS, Freiburg Institute for Advanced Studies, Albert-Ludwigs-Universität Freiburg, Albertstrasse 19, 79104 Freiburg, Germany, IMTEK, Institute for Microsystem Technology, University of Freiburg, Georges-Köhler-Allee 103, 79110 Freiburg, Germany, and MESA+ Institute for Nanotechnology/Lab-on-a-Chip Group, Twente University, Building Carré, 7500 AE, Enschede, The Netherlands
| | - Jung Tae Kim
- KIST Europe, Korea Institute of Science and Technology, Campus E71, 66123 Saarbrücken, Germany, FRIAS, Freiburg Institute for Advanced Studies, Albert-Ludwigs-Universität Freiburg, Albertstrasse 19, 79104 Freiburg, Germany, IMTEK, Institute for Microsystem Technology, University of Freiburg, Georges-Köhler-Allee 103, 79110 Freiburg, Germany, and MESA+ Institute for Nanotechnology/Lab-on-a-Chip Group, Twente University, Building Carré, 7500 AE, Enschede, The Netherlands
| | - Andreas Manz
- KIST Europe, Korea Institute of Science and Technology, Campus E71, 66123 Saarbrücken, Germany, FRIAS, Freiburg Institute for Advanced Studies, Albert-Ludwigs-Universität Freiburg, Albertstrasse 19, 79104 Freiburg, Germany, IMTEK, Institute for Microsystem Technology, University of Freiburg, Georges-Köhler-Allee 103, 79110 Freiburg, Germany, and MESA+ Institute for Nanotechnology/Lab-on-a-Chip Group, Twente University, Building Carré, 7500 AE, Enschede, The Netherlands
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Adler M, Polinkovsky M, Gutierrez E, Groisman A. Generation of oxygen gradients with arbitrary shapes in a microfluidic device. LAB ON A CHIP 2010; 10:388-91. [PMID: 20091013 PMCID: PMC2887752 DOI: 10.1039/b920401f] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
We present a system consisting of a microfluidic device made of gas-permeable polydimethylsiloxane (PDMS) with two layers of microchannels and a computer-controlled multi-channel gas mixer. Concentrations of oxygen in the liquid-filled flow channels of the device are imposed by flowing gas mixtures with desired oxygen concentrations through gas channels directly above the flow channels. Oxygen gradients with different linear, exponential, and non-monotonic shapes are generated in the same liquid-filled microchannel and reconfigured in real time. The system can be used to study directed migration of cells and the development of cell and tissue cultures under gradients of oxygen.
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Affiliation(s)
- Micha Adler
- Department of Physics, University of California, San Diego, 9500 Gilman Drive, MC 0374, La Jolla, CA, 92093, USA
| | - Mark Polinkovsky
- Department of Physics, University of California, San Diego, 9500 Gilman Drive, MC 0374, La Jolla, CA, 92093, USA
| | - Edgar Gutierrez
- Department of Physics, University of California, San Diego, 9500 Gilman Drive, MC 0374, La Jolla, CA, 92093, USA
| | - Alex Groisman
- Department of Physics, University of California, San Diego, 9500 Gilman Drive, MC 0374, La Jolla, CA, 92093, USA
- Corresponding author,
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Dai L, Cai W, Xin F. Numerical Study on Bubble Formation of a Gas-Liquid Flow in a T-Junction Microchannel. Chem Eng Technol 2009. [DOI: 10.1002/ceat.200900351] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Polinkovsky M, Gutierrez E, Levchenko A, Groisman A. Fine temporal control of the medium gas content and acidity and on-chip generation of series of oxygen concentrations for cell cultures. LAB ON A CHIP 2009; 9:1073-84. [PMID: 19350089 DOI: 10.1039/b816191g] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
We describe the design, operation, and applications of two microfluidic devices that generate series of concentrations of oxygen, [O(2)], by on-chip gas mixing. Both devices are made of polydimethylsiloxane (PDMS) and have two layers of channels, the flow layer and the gas layer. By using in-situ measurements of [O(2)] with an oxygen-sensitive fluorescent dye, we show that gas diffusion through PDMS leads to equilibration of [O(2)] in an aqueous solution in the flow layer with [O(2)] in a gas injected into the gas layer on a time scale of approximately 1 sec. Injection of carbon dioxide into the gas layer causes the pH in the flow layer to drop within approximately 0.5 sec. Gas-mixing channel networks of both devices generate series of 9 gas mixtures with different [O(2)] from two gases fed to the inlets, thus creating regions with 9 different [O(2)] in the flow layer. The first device generates nitrogen-oxygen mixtures with [O(2)] varying linearly between 0 and 100%. The second device generates nitrogen-air mixtures with [O(2)] varying exponentially between 0 and 20.9%. The flow layers of the devices are designed for culturing bacteria in semi-permeable microchambers, and the second device is used to measure growth curves of E. coli colonies at 9 different [O(2)] in a single experiment. The cell division rates at [O(2)] of 0, 0.2, and 0.5% are found to be significantly different, further validating the capacity of the device to set [O(2)] in the flow layer with high precision and resolution. The degree of control of [O(2)] achieved in the devices and the robustness with respect to oxygen consumption due to respiration would be difficult to match in a traditional large-scale culture. The proposed devices and technology can be used in research on bacteria and yeast under microaerobic conditions and on mammalian cells under hypoxia.
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Affiliation(s)
- Mark Polinkovsky
- Department of Physics, University of California, San Diego, , 9500 Gilman Drive, MC 0374, La Jolla, CA 92093, USA
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