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Kashaninejad N, Nguyen NT. Microfluidic solutions for biofluids handling in on-skin wearable systems. LAB ON A CHIP 2023; 23:913-937. [PMID: 36628970 DOI: 10.1039/d2lc00993e] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
On-skin wearable systems for biofluid sampling and biomarker sensing can revolutionize the current practices in healthcare monitoring and personalized medicine. However, there is still a long path toward complete market adoption and acceptance of this fascinating technology. Accordingly, microfluidic science and technology can provide excellent solutions for bridging the gap between basic research and clinical research. The research gap has led to the emerging field of epidermal microfluidics. Moreover, recent advances in the fabrication of highly flexible and stretchable microfluidic systems have revived the concept of micro elastofluidics, which can provide viable solutions for on-skin wearable biofluid handling. In this context, this review highlights the current state-of-the-art platforms in this field and discusses the potential technologies that can be used for on-skin wearable devices. Toward this aim, we first compare various microfluidic platforms that could be used for on-skin wearable devices. These platforms include semiconductor-based, polymer-based, liquid metal-based, paper-based, and textile-based microfluidics. Next, we discuss how these platforms can enhance the stretchability of on-skin wearable biosensors at the device level. Next, potential microfluidic solutions for collecting, transporting, and controlling the biofluids are discussed. The application of finger-powered micropumps as a viable solution for precise and on-demand biofluid pumping is highlighted. Finally, we present the future directions of this field by emphasizing the applications of droplet-based microfluidics, stretchable continuous-flow micro elastofluidics, stretchable superhydrophobic surfaces, liquid beads as a form of digital micro elastofluidics, and topological liquid diodes that received less attention but have enormous potential to be integrated into on-skin wearable devices.
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Affiliation(s)
- Navid Kashaninejad
- Queensland Micro- and Nanotechnology Centre, Griffith University, 170 Kessels Road, Nathan, QLD 4111, Australia.
| | - Nam-Trung Nguyen
- Queensland Micro- and Nanotechnology Centre, Griffith University, 170 Kessels Road, Nathan, QLD 4111, Australia.
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2
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Qin D, Gibbons AH, Ito MM, Parimalam SS, Jiang H, Enis Karahan H, Ghalei B, Yamaguchi D, Pandian GN, Sivaniah E. Structural colour enhanced microfluidics. Nat Commun 2022; 13:2281. [PMID: 35589687 PMCID: PMC9120135 DOI: 10.1038/s41467-022-29956-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Accepted: 04/08/2022] [Indexed: 01/11/2023] Open
Abstract
Advances in microfluidic technology towards flexibility, transparency, functionality, wearability, scale reduction or complexity enhancement are currently limited by choices in materials and assembly methods. Organized microfibrillation is a method for optically printing well-defined porosity into thin polymer films with ultrahigh resolution. Here we demonstrate this method to create self-enclosed microfluidic devices with a few simple steps, in a number of flexible and transparent formats. Structural colour, a property of organized microfibrillation, becomes an intrinsic feature of these microfluidic devices, enabling in-situ sensing capability. Since the system fluid dynamics are dependent on the internal pore size, capillary flow is shown to become characterized by structural colour, while independent of channel dimension, irrespective of whether devices are printed at the centimetre or micrometre scale. Moreover, the capability of generating and combining different internal porosities enables the OM microfluidics to be used for pore-size based applications, as demonstrated by separation of biomolecular mixtures.
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Affiliation(s)
- Detao Qin
- Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University of Advanced Study, Kyoto University, 606-8501, Kyoto, Japan
- Department of Molecular Engineering, Kyoto University, 616-8510, Kyoto, Japan
| | - Andrew H Gibbons
- Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University of Advanced Study, Kyoto University, 606-8501, Kyoto, Japan
- Department of Molecular Engineering, Kyoto University, 616-8510, Kyoto, Japan
| | - Masateru M Ito
- Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University of Advanced Study, Kyoto University, 606-8501, Kyoto, Japan.
- Department of Molecular Engineering, Kyoto University, 616-8510, Kyoto, Japan.
| | | | - Handong Jiang
- Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University of Advanced Study, Kyoto University, 606-8501, Kyoto, Japan
- Department of Molecular Engineering, Kyoto University, 616-8510, Kyoto, Japan
| | - H Enis Karahan
- Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University of Advanced Study, Kyoto University, 606-8501, Kyoto, Japan
- Department of Molecular Engineering, Kyoto University, 616-8510, Kyoto, Japan
| | - Behnam Ghalei
- Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University of Advanced Study, Kyoto University, 606-8501, Kyoto, Japan
- Department of Molecular Engineering, Kyoto University, 616-8510, Kyoto, Japan
| | - Daisuke Yamaguchi
- Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University of Advanced Study, Kyoto University, 606-8501, Kyoto, Japan
- Department of Molecular Engineering, Kyoto University, 616-8510, Kyoto, Japan
| | - Ganesh N Pandian
- Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University of Advanced Study, Kyoto University, 606-8501, Kyoto, Japan
- Department of Molecular Engineering, Kyoto University, 616-8510, Kyoto, Japan
| | - Easan Sivaniah
- Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University of Advanced Study, Kyoto University, 606-8501, Kyoto, Japan.
- Department of Molecular Engineering, Kyoto University, 616-8510, Kyoto, Japan.
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3
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Li L, Westerbeek EY, Vollenbroek JC, de Beer S, Shui L, Odijk M, Eijkel JCT. Autonomous capillary microfluidic devices with constant flow rate and temperature-controlled valving. SOFT MATTER 2021; 17:7781-7791. [PMID: 34351350 DOI: 10.1039/d1sm00625h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
In this paper, we report on a capillary microfluidic device with constant flow rate and temperature-triggered stop valve function. It contains a PDMS channel that was grafted by a thermo-responsive polymer poly(N-isopropylacrylamide) (PNIPAm). The channel exhibits a constant capillary filling speed. By locally increasing the temperature in the channel from 20 °C to 37 °C using a microfabricated heater, a change of the surface wettability from hydrophilic to hydrophobic is obtained creating a hydrophobic stop valve. The valve can be reopened by lowering the temperature. The device is simple to fabricate and can be used as an actuatable capillary pump operating around room temperature. To understand the constant capillary filling speed, we performed contact angle measurements, in which we found slow wetting kinetics of PNIPAm-g-PDMS surfaces at temperatures below the lower critical solution temperature (LCST) of PNIPAm and fast wetting kinetics above the LCST. We interpret this as the result of the diffusive hydration process of PNIPAm below the LCST and the absence of hydration on the hydrophobic PNIPAm thin layer above the LCST.
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Affiliation(s)
- Lanhui Li
- National Center for International Research on Green Optoelectronics & South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, China.
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Multistory Stairs-based, Fast and Point-of-care Testing for Disease Biomarker Using One-step Capillary Microfluidic Fluoroimmunoassay Chip via Continuous On-chip Labelling. BIOCHIP JOURNAL 2021. [DOI: 10.1007/s13206-021-00025-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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Dirksen M, Brändel T, Großkopf S, Knust S, Bookhold J, Anselmetti D, Hellweg T. UV cross-linked smart microgel membranes as free-standing diffusion barriers and nanoparticle bearing catalytic films. RSC Adv 2021; 11:22014-22024. [PMID: 35480797 PMCID: PMC9036384 DOI: 10.1039/d1ra03528b] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 06/15/2021] [Indexed: 01/04/2023] Open
Abstract
In this study we use poly(N-isopropylacrylamide) (PNIPAM) based copolymer microgels to create free-standing, transferable, thermoresponsive membranes. The microgels are synthesized by copolymerization of NIPAM with 2-hydroxy-4-(methacryloyloxy)–benzophenone (HMABP) and spin-coated on Si wafers. After subsequent cross-linking by UV-irradiation, the formed layers easily detach from the supporting material. We obtain free standing microgel membranes with lateral extensions of several millimetres and an average layer thickness of a few hundred nanometres. They can be transferred to other substrates. As one example for potential applications we investigate the temperature dependent ion transport through the membranes via resistance measurements revealing a sharp reversible increase in resistance when the lower critical solution temperature of the copolymer microgels is reached. In addition, prior to cross-linking, the microgels can be decorated with silver nanoparticles and cross-linked afterwards. Such free-standing nanoparticle hybrid membranes are then used as catalytic systems for the reduction of 4-nitrophenol, which is monitored by UV/Vis spectroscopy. Cross-linkable microgels are synthesized by copolymerization of NIPAM with 2-hydroxy-4-(methacryloyloxy)–benzophenone (HMABP) and are subsequently UV-cross-linked to obtain smart membranes exhibiting switchable resistance.![]()
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Affiliation(s)
- Maxim Dirksen
- Department of Chemistry, Physical and Biophysical Chemistry
- University Bielefeld
- D-33615 Bielefeld
- Germany
| | - Timo Brändel
- Department of Chemistry, Physical and Biophysical Chemistry
- University Bielefeld
- D-33615 Bielefeld
- Germany
| | - Sören Großkopf
- Department of Chemistry, Physical and Biophysical Chemistry
- University Bielefeld
- D-33615 Bielefeld
- Germany
| | - Sebastian Knust
- Department of Physics, Experimental Biophysics
- University Bielefeld
- D-33615 Bielefeld
- Germany
| | - Johannes Bookhold
- Department of Chemistry, Physical and Biophysical Chemistry
- University Bielefeld
- D-33615 Bielefeld
- Germany
| | - Dario Anselmetti
- Department of Physics, Experimental Biophysics
- University Bielefeld
- D-33615 Bielefeld
- Germany
| | - Thomas Hellweg
- Department of Chemistry, Physical and Biophysical Chemistry
- University Bielefeld
- D-33615 Bielefeld
- Germany
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6
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Zhu WJ, Zhong WR, Xiong JW, Ai BQ. Transport of particles driven by the traveling obstacle arrays. J Chem Phys 2018; 149:174906. [PMID: 30409003 DOI: 10.1063/1.5049719] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Transport of three types of particles (passive particles, active particles without polar interaction, and active particles with polar interaction) is numerically investigated in the presence of traveling obstacle arrays. The transport behaviors are different for different types of particles. For passive particles, there exists an optimal traveling speed (or the translational diffusion) at which the average velocity of particles takes its maximum value. For active particles without polar interaction, the average velocity of particles is a peaked function of the obstacle traveling speed. The average velocity decreases monotonically with increase of the rotational diffusion for large driving speed, while it is a peaked function of the rotational diffusion for small driving speed. For active particles with polar interaction, interestingly, within particular parameter regimes, active particles can move in the opposite direction to the obstacles. The average velocity of particles can change its direction by changing the system parameters (the obstacles driving speed, the polar interaction strength, and the rotational diffusion).
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Affiliation(s)
- Wei-Jing Zhu
- Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials, School of Physics and Telecommunication Engineering, South China Normal University, Guangzhou 510006, China
| | - Wei-Rong Zhong
- Siyuan Laboratory, Guangzhou Key Laboratory of Vacuum Coating Technologies and New Energy Materials, Department of Physics, Jinan University, Guangzhou 510632, China
| | - Jian-Wen Xiong
- Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials, School of Physics and Telecommunication Engineering, South China Normal University, Guangzhou 510006, China
| | - Bao-Quan Ai
- Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials, School of Physics and Telecommunication Engineering, South China Normal University, Guangzhou 510006, China
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Olanrewaju A, Beaugrand M, Yafia M, Juncker D. Capillary microfluidics in microchannels: from microfluidic networks to capillaric circuits. LAB ON A CHIP 2018; 18:2323-2347. [PMID: 30010168 DOI: 10.1039/c8lc00458g] [Citation(s) in RCA: 166] [Impact Index Per Article: 27.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Microfluidics offer economy of reagents, rapid liquid delivery, and potential for automation of many reactions, but often require peripheral equipment for flow control. Capillary microfluidics can deliver liquids in a pre-programmed manner without peripheral equipment by exploiting surface tension effects encoded by the geometry and surface chemistry of a microchannel. Here, we review the history and progress of microchannel-based capillary microfluidics spanning over three decades. To both reflect recent experimental and conceptual progress, and distinguish from paper-based capillary microfluidics, we adopt the more recent terminology of capillaric circuits (CCs). We identify three distinct waves of development driven by microfabrication technologies starting with early implementations in industry using machining and lamination, followed by development in the context of micro total analysis systems (μTAS) and lab-on-a-chip devices using cleanroom microfabrication, and finally a third wave that arose with advances in rapid prototyping technologies. We discuss the basic physical laws governing capillary flow, deconstruct CCs into basic circuit elements including capillary pumps, stop valves, trigger valves, retention valves, and so on, and describe their operating principle and limitations. We discuss applications of CCs starting with the most common usage in automating liquid delivery steps for immunoassays, and highlight emerging applications such as DNA analysis. Finally, we highlight recent developments in rapid prototyping of CCs and the benefits offered including speed, low cost, and greater degrees of freedom in CC design. The combination of better analytical models and lower entry barriers (thanks to advances in rapid manufacturing) make CCs both a fertile research area and an increasingly capable technology for user-friendly and high-performance laboratory and diagnostic tests.
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Affiliation(s)
- Ayokunle Olanrewaju
- Biomedical Engineering Department, McGill University, Genome Quebec and McGill University Innovation Centre, Canada.
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8
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Thomas R, Harrison A, Barrow D, Smowton PM. Photonic integration platform with pump free microfluidics. OPTICS EXPRESS 2017; 25:23634-23644. [PMID: 29041314 DOI: 10.1364/oe.25.023634] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 08/27/2017] [Indexed: 06/07/2023]
Abstract
Chip based particle sensing using 3D capillary fill microfluidics integrated with monolithically integrated lasers and photodetectors is used to demonstrate the feasibility of true chip scale photonic measurements of fluids. The approach is scalable and manufactured using industry standard compound semiconductor fabrication tools. The need for fluid speed regulation via external pumps is removed by measuring local particle velocity at the point of interrogation and particle position within the fluid flow is derived from multiple time resolved forward scattered light signals. Particle size discrimination of 10 and 15 μm polystyrene microbeads is used as an example.
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9
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Gorthi SR, Mondal PK, Biswas G. Magnetic-field-driven alteration in capillary filling dynamics in a narrow fluidic channel. Phys Rev E 2017; 96:013113. [PMID: 29347204 DOI: 10.1103/physreve.96.013113] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2017] [Indexed: 06/07/2023]
Abstract
We investigated pressure-driven transport of an immiscible binary system, constituted by two electrically conducting liquids, in a narrow fluidic channel under the influence of an externally applied magnetic field. The surface wettability was taken into account in the analysis considering that the walls of the channel are chemically treated to obtain various predefined contact angles as required for the study. Alterations in the capillary filling and wetting dynamics in the channel stemming from a complex interplay among different forces acting over the interface were investigated. It was shown that an alteration in the strength of the magnetic field leads to an alteration in the dynamics of the interface, which in turn, alters the filling and wetting dynamics nontrivially upon interaction with the surface tension force due to the wetted walls of the channel. It is emphasized that a contrast in properties of constituents of the binary system gives rise to an alteration in the forces being applied across the interface, leading to an intricate control over the filling and wetting dynamics for a given flow configuration and an applied field strength. We believe that the results obtained from this analysis may aid the design of microfluidic devices used for multiphase transport.
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Affiliation(s)
- Srinivas R Gorthi
- Department of Mechanical Engineering, Indian Institute of Technology, Guwahati 781039, India
| | - Pranab Kumar Mondal
- Department of Mechanical Engineering, Indian Institute of Technology, Guwahati 781039, India
| | - Gautam Biswas
- Department of Mechanical Engineering, Indian Institute of Technology, Guwahati 781039, India
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10
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Bandopadhyay A, Mandal S, Chakraborty S. Capillary transport of two immiscible fluids in presence of electroviscous retardation. Electrophoresis 2017; 38:747-754. [DOI: 10.1002/elps.201600395] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 12/06/2016] [Accepted: 12/08/2016] [Indexed: 11/06/2022]
Affiliation(s)
| | - Shubhadeep Mandal
- Department of Mechanical Engineering; Indian Institute of Technology Kharagpur; Kharagpur India
| | - Suman Chakraborty
- Department of Mechanical Engineering; Indian Institute of Technology Kharagpur; Kharagpur India
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11
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Zhu Q, Trau D. PEG-based autonomous capillary system with integrated microbead array for immunoassay. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2017; 70:1031-1038. [DOI: 10.1016/j.msec.2016.02.037] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Revised: 02/05/2016] [Accepted: 02/12/2016] [Indexed: 11/17/2022]
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12
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Bandopadhyay A, Mandal S, Chakraborty S. Streaming potential-modulated capillary filling dynamics of immiscible fluids. SOFT MATTER 2016; 12:2056-2065. [PMID: 26758228 DOI: 10.1039/c5sm02687c] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The pressure driven transport of two immiscible electrolytes in a narrow channel with prescribed surface potential (zeta potential) is considered under the influence of a flow-induced electric field. The latter consideration is non-trivially and fundamentally different from the problem of electric field-driven motion (electroosmosis) of two immiscible electrolytes in a channel in a sense that in the former case, the genesis of the induced electric field, termed as streaming potential, is the advection of ions in the absence of any external electric field. As the flow occurs, one fluid displaces the other. Consequently, in cases where the conductivities of the two fluids differ, imbibition dynamically alters the net conductivity of the channel. We emphasize, through numerical simulations, that the alteration in the net conductivity has a significant impact on the contact line dynamics and the concomitant induced streaming potential. The results presented herein are expected to shed light on multiphase electrokinetics devices.
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Affiliation(s)
- Aditya Bandopadhyay
- Advanced Technology Development Center, Indian Institute of Technology Kharagpur, Kharagpur - 721302, India
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13
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Brouzes E, Kruse T, Kimmerling R, Strey HH. Rapid and continuous magnetic separation in droplet microfluidic devices. LAB ON A CHIP 2015; 15:908-19. [PMID: 25501881 PMCID: PMC4323160 DOI: 10.1039/c4lc01327a] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
We present a droplet microfluidic method to extract molecules of interest from a droplet in a rapid and continuous fashion. We accomplish this by first marginalizing functionalized super-paramagnetic beads within the droplet using a magnetic field, and then splitting the droplet into one droplet containing the majority of magnetic beads and one droplet containing the minority fraction. We quantitatively analysed the factors which affect the efficiency of marginalization and droplet splitting to optimize the enrichment of magnetic beads. We first characterized the interplay between the droplet velocity and the strength of the magnetic field and its effect on marginalization. We found that marginalization is optimal at the midline of the magnet and that marginalization is a good predictor of bead enrichment through splitting at low to moderate droplet velocities. Finally, we focused our efforts on manipulating the splitting profile to improve the enrichment provided by asymmetric splitting. We designed asymmetric splitting forks that employ capillary effects to preferentially extract the bead-rich regions of the droplets. Our strategy represents a framework to optimize magnetic bead enrichment methods tailored to the requirements of specific droplet-based applications. We anticipate that our separation technology is well suited for applications in single-cell genomics and proteomics. In particular, our method could be used to separate mRNA bound to poly-dT functionalized magnetic microparticles from single cell lysates to prepare single-cell cDNA libraries.
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Affiliation(s)
- Eric Brouzes
- Biomedical Engineering Department, Stony Brook University, Stony Brook, NY 11794-5281, USA.
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14
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Mondal PK, Ghosh U, Bandopadhyay A, DasGupta D, Chakraborty S. Pulsating electric field modulated contact line dynamics of immiscible binary systems in narrow confinements under an electrical double layer phenomenon. SOFT MATTER 2014; 10:8512-8523. [PMID: 25242073 DOI: 10.1039/c4sm01583e] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We investigate the interfacial electro-chemical-hydrodynamics of an incompressible immiscible binary fluid system that moves in a narrow fluidic channel under time-periodic electroosmotic effects. We apply an alternating electrical voltage that sets the binary fluids in motion along the channel, whereas the channel walls are lined with chemical patch to alter the wetting characteristics of the surface. We demonstrate that the pulsating nature of the externally applied electric field in conjunction with the wetting characteristics of the surface may lead to some fascinating behavior of the contact line motion; which, in turn, may affect the capillary filling dynamics in an intriguing manner. Our results also unveil the profound influence of two important governing factors actuating the flow, namely, the frequency and amplitude of the time periodic electric field, on the tunability of the capillary filling rate and power requirement for filling the fluids into the channel.
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Affiliation(s)
- Pranab Kumar Mondal
- Department of Mechanical Engineering, Indian Institute of Technology Kharagpur, West Bengal 721302, India
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15
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Godwin LA, Deal KS, Hoepfner LD, Jackson LA, Easley CJ. Measurement of microchannel fluidic resistance with a standard voltage meter. Anal Chim Acta 2012; 758:101-7. [PMID: 23245901 DOI: 10.1016/j.aca.2012.10.043] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2012] [Revised: 10/16/2012] [Accepted: 10/20/2012] [Indexed: 10/27/2022]
Abstract
A simplified method for measuring the fluidic resistance (R(fluidic)) of microfluidic channels is presented, in which the electrical resistance (R(elec)) of a channel filled with a conductivity standard solution can be measured and directly correlated to R(fluidic) using a simple equation. Although a slight correction factor could be applied in this system to improve accuracy, results showed that a standard voltage meter could be used without calibration to determine R(fluidic) to within 12% error. Results accurate to within 2% were obtained when a geometric correction factor was applied using these particular channels. When compared to standard flow rate measurements, such as meniscus tracking in outlet tubing, this approach provided a more straightforward alternative and resulted in lower measurement error. The method was validated using 9 different fluidic resistance values (from ∼40 to 600kPa smm(-3)) and over 30 separately fabricated microfluidic devices. Furthermore, since the method is analogous to resistance measurements with a voltage meter in electrical circuits, dynamic R(fluidic) measurements were possible in more complex microfluidic designs. Microchannel R(elec) was shown to dynamically mimic pressure waveforms applied to a membrane in a variable microfluidic resistor. The variable resistor was then used to dynamically control aqueous-in-oil droplet sizes and spacing, providing a unique and convenient control system for droplet-generating devices. This conductivity-based method for fluidic resistance measurement is thus a useful tool for static or real-time characterization of microfluidic systems.
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Affiliation(s)
- Leah A Godwin
- Auburn University, Department of Chemistry and Biochemistry, Auburn, AL 36849, United States
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Eaton SM, De Marco C, Martinez-Vazquez R, Ramponi R, Turri S, Cerullo G, Osellame R. Femtosecond laser microstructuring for polymeric lab-on-chips. JOURNAL OF BIOPHOTONICS 2012; 5:687-702. [PMID: 22589025 DOI: 10.1002/jbio.201200048] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2012] [Revised: 04/12/2012] [Accepted: 04/19/2012] [Indexed: 05/16/2023]
Abstract
This paper provides an overview of femtosecond laser microfabrication in polymeric materials, with emphasis on lab-on-chip applications. Due to the nonlinear interaction of femtosecond laser pulses with polymers, laser-induced modifications are localized to the focal volume, enabling high resolution patterning in 3D. Femtosecond laser microfabrication offers unmatched versatility in fabricating surface microchannels and diffractive optics by means of laser ablation, buried optical waveguides and micro-optics through refractive index modification and complex 3D microstructures in photoresists by two-photon polymerization. Femtosecond laser microfabrication technology opens the door to fabricating integrated lab-on-chip devices with a single tool.
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Affiliation(s)
- Shane M Eaton
- Istituto di Fotonica e Nanotecnologie IFN - CNR and Dipartimento di Fisica - Politecnico di Milano, P.zza L. da Vinci 32, 20133 Milano, Italy.
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17
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Xu BY, Hu SW, Yan XN, Xia XH, Xu JJ, Chen HY. On chip steady liquid-gas phase separation for flexible generation of dissolved gas concentration gradient. LAB ON A CHIP 2012; 12:1281-1288. [PMID: 22336913 DOI: 10.1039/c2lc20985c] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
In this study, steady liquid-gas phase separation is realized by applying a hydrophobic small microchannel array (SMA) to bridge two large microchannels, one for liquid phase and one for gas phase. In this structure, a capillary pressure difference between that in the SMA and the larger channel results in a steady liquid-gas interface. The generated liquid-gas interface allows for fast gas dissolving speed. By coupling the liquid-gas interface with a one directional fluidic field, a steady dissolved gas concentration gradient (DgCG) is generated. The DgCG distribution is easily designable for linear or exponential modes, providing improved flexibility for gas participated processes on chip. To demonstrate its applicability, a CO(2) DgCG chip is fabricated and applied for screening CaCO(3) crystal growth conditions in the DgCG chip. Crystals with transitional structures are successfully fabricated, which is consistent with the CO(2) DgCG distribution.
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Affiliation(s)
- Bi-Yi Xu
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, PR China
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18
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Amato L, Gu Y, Bellini N, Eaton SM, Cerullo G, Osellame R. Integrated three-dimensional filter separates nanoscale from microscale elements in a microfluidic chip. LAB ON A CHIP 2012; 12:1135-42. [PMID: 22318474 DOI: 10.1039/c2lc21116e] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
We report on the integration of a size-based three-dimensional filter, with micrometre-sized pores, in a commercial microfluidic chip. The filter is fabricated inside an already sealed microfluidic channel using the unique capabilities of two-photon polymerization. This direct-write technique enables integration of the filter by post-processing in a chip that has been fabricated by standard technologies. The filter is located at the intersection of two channels in order to control the amount of flow passing through the filter. Tests with a suspension of 3 μm polystyrene spheres in a Rhodamine 6G solution show that 100% of the spheres are stopped, while the fluorescent molecules are transmitted through the filter. We demonstrate operation up to a period of 25 minutes without any evidence of clogging. Preliminary validation of the device for plasma separation from whole blood is shown. Moreover, the filter can be cleaned and reused by reversing the flow.
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Affiliation(s)
- Lorenzo Amato
- Istituto di Fotonica e Nanotecnologie-CNR, Dipartimento di Fisica-Politecnico di Milano, Milan, Italy
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19
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Gubala V, Harris LF, Ricco AJ, Tan MX, Williams DE. Point of Care Diagnostics: Status and Future. Anal Chem 2011; 84:487-515. [DOI: 10.1021/ac2030199] [Citation(s) in RCA: 832] [Impact Index Per Article: 64.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Vladimir Gubala
- Biomedical Diagnostics Institute, Dublin City University, Dublin 9, Ireland
| | - Leanne F. Harris
- Biomedical Diagnostics Institute, Dublin City University, Dublin 9, Ireland
| | - Antonio J. Ricco
- Biomedical Diagnostics Institute, Dublin City University, Dublin 9, Ireland
| | - Ming X. Tan
- Biomedical Diagnostics Institute, Dublin City University, Dublin 9, Ireland
| | - David E. Williams
- Biomedical Diagnostics Institute, Dublin City University, Dublin 9, Ireland
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20
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Vulto P, Podszun S, Meyer P, Hermann C, Manz A, Urban GA. Phaseguides: a paradigm shift in microfluidic priming and emptying. LAB ON A CHIP 2011; 11:1596-602. [PMID: 21394334 DOI: 10.1039/c0lc00643b] [Citation(s) in RCA: 135] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Phaseguide technology gives complete control over filling and emptying of any type of microfluidic structures, independent of the chamber and channel geometry. The technique is based on a step-wise advancement of the liquid-air interface using the meniscus pinning effect. In this paper, the main effects and parameters underlying the phaseguiding principle are discussed and a demonstration is given of its potential for dead angle filling, spatially controlled phaseguide overflow and sequential phaseguide overflow, all accumulating in a passive valving approach. Phaseguides represent a new direction in microfluidic design thinking that will prove a leap forward towards more simple, flexible and reliable microfluidic systems.
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Affiliation(s)
- Paul Vulto
- Laboratory for Sensors, Department of Microsystems Engineering, 60 (IMTEK), Albert-Ludwigs-Universität Freiburg, Georges-Köhler-Allee 103, Freiburg, Germany.
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21
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Partition-induced vector chromatography in microfluidic devices. J Colloid Interface Sci 2011; 356:341-51. [DOI: 10.1016/j.jcis.2010.11.069] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2010] [Revised: 09/26/2010] [Accepted: 11/23/2010] [Indexed: 11/18/2022]
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22
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Kulrattanarak T, van der Sman R, Lubbersen Y, Schroën C, Pham H, Sarro P, Boom R. Mixed motion in deterministic ratchets due to anisotropic permeability. J Colloid Interface Sci 2011; 354:7-14. [DOI: 10.1016/j.jcis.2010.10.020] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2010] [Revised: 10/06/2010] [Accepted: 10/08/2010] [Indexed: 10/18/2022]
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23
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Parikesit GOF, Vrouwe EX, Blom MT, Westerweel J. Observation of hydrophobic-like behavior in geometrically patterned hydrophilic microchannels. BIOMICROFLUIDICS 2010; 4:44103. [PMID: 21042432 PMCID: PMC2966485 DOI: 10.1063/1.3499416] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2010] [Accepted: 09/18/2010] [Indexed: 05/07/2023]
Abstract
We present our observation of meta-hydrophobicity, where geometrically patterned surfaces make hydrophilic microchannels exhibit hydrophobic-like behaviors. We analyze the wetting-induced energy decrease that results from the surface geometries and experimentally demonstrate how those geometries can modulate the dynamics of capillary-driven wetting and evaporation-driven drying of microfluidic systems. Our results also show that the modulated wetting dynamics can be employed to generate regulated patterns of microbubbles.
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24
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Kim BK, Yang SY, Aziz MA, Jo K, Sung D, Jon S, Woo HY, Yang H. Electrochemical Immunosensing Chip Using Selective Surface Modification, Capillary-Driven Microfluidic Control, and Signal Amplification by Redox Cycling. ELECTROANAL 2010. [DOI: 10.1002/elan.201000148] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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25
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Floris A, Staal S, Lenk S, Staijen E, Kohlheyer D, Eijkel J, van den Berg A. A prefilled, ready-to-use electrophoresis based lab-on-a-chip device for monitoring lithium in blood. LAB ON A CHIP 2010; 10:1799-806. [PMID: 20532263 DOI: 10.1039/c003899g] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
We present the Medimate Multireader, the first point-of-care lab on a chip device that is based on capillary electrophoresis. It employs disposable pre-filled microfluidic chips with closed electrode reservoirs and a single sample opening. Several technological innovations allow operation with closed reservoirs, which is essential for reliable point-of-care operation. The chips are inserted into a hand-held analyzer. In the present application, the device is used to measure the lithium concentration in blood. Lithium is quantified by conductivity detection after separation from other blood ions. Measurements in patients show good accuracy and precision, and there is no difference between the results obtained by skilled and non-skilled operators. This point-of-care device shows great promise as a platform for the determination of ionic substances in diagnostics or environmental analysis.
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26
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Napoli M, Eijkel JCT, Pennathur S. Nanofluidic technology for biomolecule applications: a critical review. LAB ON A CHIP 2010; 10:957-85. [PMID: 20358103 DOI: 10.1039/b917759k] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
In this review, we present nanofluidic phenomena, particularly as they relate to applications involving analysis of biomolecules within nanofabricated devices. The relevant length scales and physical phenomena that govern biomolecule transport and manipulation within nanofabricated nanofluidic devices are reviewed, the advantages of nanofabricated devices are presented, and relevant applications are cited. Characteristic length scales include the Debye length, the Van der Waals radius, the action distance of hydrogen bonding, the slip length, and macromolecular dimensions. On the basis of the characteristic lengths and related nanofluidic phenomena, a nanofluidic toolbox will be assembled. Nanofluidic phenomena that affect biomolecule behavior within such devices can include ion depletion and enrichment, modified velocity and mobility, permselectivity, steric hindrance, entropy, adsorption, and hydrodynamic interaction. The complex interactions and coupled physics of such phenomena allow for many applications, including biomolecule separation, concentration, reaction/hybridization, sequencing (in the case of DNA) and detection. Examples of devices for such applications will be presented, followed by a discussion of near-term challenges and future thoughts for the field.
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Affiliation(s)
- M Napoli
- Engineering II Building, Room 2330, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
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27
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Schnietz M, Turchanin A, Nottbohm CT, Beyer A, Solak HH, Hinze P, Weimann T, Gölzhäuser A. Chemically functionalized carbon nanosieves with 1-nm thickness. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2009; 5:2651-2655. [PMID: 19787678 DOI: 10.1002/smll.200901283] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Affiliation(s)
- Mark Schnietz
- Fakultät für Physik, Universität Bielefeld, Bielefeld, Germany
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28
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Fu J, Mao P, Han J. Continuous-flow bioseparation using microfabricated anisotropic nanofluidic sieving structures. Nat Protoc 2009; 4:1681-98. [PMID: 19876028 PMCID: PMC2896887 DOI: 10.1038/nprot.2009.176] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The anisotropic nanofluidic-filter (nanofilter) array (ANA) is a unique molecular-sieving structure for separating biomolecules. In this protocol we describe the fabrication of planar and vertical ANA chips and how to perform continuous-flow bioseparation using them. This protocol is most useful for bioengineers who are interested in developing automated multistep chip-based bioanalysis systems and assumes previous cleanroom microfabrication knowledge. The ANA consists of a two-dimensional periodic nanofilter array, and the designed structural anisotropy of ANA causes different-sized or charged biomolecules to follow distinct trajectories under applied electric fields, leading to efficient continuous-flow separation. Using microfluidic channels surrounding the ANA, the fractionated biomolecule streams are collected and routed to different fluid channels or reservoirs for convenient sample recovery and downstream bioanalysis. The ANA is physically robust and can be reused repeatedly. Compared with the conventional gel-based separation techniques, ANA offers the potential for faster separation, higher throughput and more convenient sample recovery.
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Affiliation(s)
- Jianping Fu
- Research Laboratories of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
- Department of Electrical Engineering and Computer Science, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Pan Mao
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Jongyoon Han
- Department of Electrical Engineering and Computer Science, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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29
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Boukellal H, Selimović S, Jia Y, Cristobal G, Fraden S. Simple, robust storage of drops and fluids in a microfluidic device. LAB ON A CHIP 2009; 9:331-8. [PMID: 19107293 DOI: 10.1039/b808579j] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
We describe a single microfluidic device and two methods for the passive storage of aqueous drops in a continuous stream of oil without any external control but hydrodynamic flow. Advantages of this device are that it is simple to manufacture, robust under operation, and drops never come into contact with each other, making it unnecessary to stabilize drops against coalescence. In one method the device can be used to store drops that are created upstream from the storage zone. In the second method the same device can be used to simultaneously create and store drops from a single large continuous fluid stream without resorting to the usual flow focusing or T-junction drop generation processes. Additionally, this device stores all the fluid introduced, including the first amount, with zero waste. Transport of drops in this device depends, however, on whether or not the aqueous drops wet the device walls. Analysis of drop transport in these two cases is presented. Finally, a method for extraction of the drops from the device is also presented, which works best when drops do not wet the walls of the chip.
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Affiliation(s)
- Hakim Boukellal
- Complex Fluids Group, Martin Fisher School of Physics, Brandeis University, Waltham, MA 02454, USA
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30
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Lateral-flow particle filtration and separation with multilayer microfluidic channels. ACTA ACUST UNITED AC 2009. [DOI: 10.1116/1.3258155] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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31
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Affiliation(s)
- Weian Zhao
- Department of Chemistry, McMaster University, Canada.
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32
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Kulrattanarak T, van der Sman RGM, Schroën CGPH, Boom RM. Classification and evaluation of microfluidic devices for continuous suspension fractionation. Adv Colloid Interface Sci 2008; 142:53-66. [PMID: 18572146 DOI: 10.1016/j.cis.2008.05.001] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2007] [Revised: 05/07/2008] [Accepted: 05/12/2008] [Indexed: 11/28/2022]
Abstract
Membrane processes are well-known for separating and fractionating suspensions in many industries, but suffer from particle accumulation on the membrane surface. Currently, there are new developments using microfluidic devices for cell/DNA sorting and fractionation. We anticipate these devices are also applicable to fractionation of polydisperse and concentrated suspensions (e.g. foods), and may potentially have fewer problems with particle accumulation compared to membranes. This review article presents an overview of relevant microfluidic devices. We focus on their performance with respect to concentrated suspensions, as one finds in food industry. We give quantitative estimates on their yield, selectivity, and the potential for large-scale application. From this evaluation follows that deterministic ratchets seem most promising.
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Affiliation(s)
- T Kulrattanarak
- Food and Bioprocess Engineering Group, Wageningen University, P.O. Box 8129, 6700 EV, Wageningen, The Netherlands.
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33
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Affiliation(s)
- Patrick Abgrall
- Singapore-MIT Alliance/School of Mechanical and Aerospace Engineering, Nanyang Technological University, Nanyang Avenue, Singapore 639798
| | - Nam Trung Nguyen
- Singapore-MIT Alliance/School of Mechanical and Aerospace Engineering, Nanyang Technological University, Nanyang Avenue, Singapore 639798
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34
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Affiliation(s)
- Jan C T Eijkel
- BIOS/Lab-on-a-Chip group, MESA+ Research Institute, University of Twente, The Netherlands.
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35
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Jeong HE, Kim P, Kwak MK, Seo CH, Suh KY. Capillary kinetics of water in homogeneous, hydrophilic polymeric micro- to nanochannels. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2007; 3:778-82. [PMID: 17352432 DOI: 10.1002/smll.200600666] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Affiliation(s)
- Hoon Eui Jeong
- School of Mechanical and Aerospace Engineering, Seoul National University, Seoul, Korea
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36
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37
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Fu J, Schoch RB, Stevens AL, Tannenbaum SR, Han J. A patterned anisotropic nanofluidic sieving structure for continuous-flow separation of DNA and proteins. NATURE NANOTECHNOLOGY 2007; 2:121-8. [PMID: 18654231 PMCID: PMC2621439 DOI: 10.1038/nnano.2006.206] [Citation(s) in RCA: 216] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2006] [Revised: 11/24/2006] [Accepted: 12/15/2006] [Indexed: 05/14/2023]
Abstract
Microfabricated regular sieving structures hold great promise as an alternative to gels to improve the speed and resolution of biomolecule separation. In contrast to disordered porous gel networks, these regular structures also provide well defined environments ideal for the study of molecular dynamics in confining spaces. However, the use of regular sieving structures has, to date, been limited to the separation of long DNA molecules, however separation of smaller, physiologically relevant macromolecules, such as proteins, still remains a challenge. Here we report a microfabricated anisotropic sieving structure consisting of a two-dimensional periodic nanofluidic filter array. The designed structural anisotropy causes different-sized or -charged biomolecules to follow distinct trajectories, leading to efficient separation. Continuous-flow size-based separation of DNA and proteins, as well as electrostatic separation of proteins, was achieved, demonstrating the potential use of this device as a generic molecular sieving structure for an integrated biomolecule sample preparation and analysis system.
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Affiliation(s)
- Jianping Fu
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Reto B. Schoch
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
- Biological Engineering Division, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Anna L. Stevens
- Biological Engineering Division, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Steven R. Tannenbaum
- Biological Engineering Division, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Jongyoon Han
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
- Biological Engineering Division, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
- Correspondence should be addressed to Jongyoon Han [J. Han (email address: , Tel: 617-253-2290, Fax: 617-258-5846)]
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