1
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Douma C, Bowser MT. Assessing Surface Adsorption in Cyclic Olefin Copolymer Microfluidic Devices Using Two-Dimensional Nano Liquid Chromatography-Micro Free Flow Electrophoresis Separations. Anal Chem 2023; 95:18379-18387. [PMID: 38060457 PMCID: PMC10733905 DOI: 10.1021/acs.analchem.3c03014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 10/11/2023] [Accepted: 10/18/2023] [Indexed: 12/20/2023]
Abstract
Surface interactions are a concern in microscale separations, where analyte adsorption can decrease the speed, sensitivity, and resolution otherwise achieved by miniaturization. Here, we functionally characterize the surface adsorption of hot-embossed cyclic olefin copolymer (COC) micro free-flow electrophoresis (μFFE) devices using two-dimensional nLC × μFFE separations, which introduce a 3- to 5 s plug of analyte into the device and measure temporal broadening that arises from surface interactions. COC is an attractive material for microfluidic devices, but little is known about its potential for surface adsorption in applications with continuous fluid flow and temporal measurements. Adsorption was minimal for three small molecule dyes: positively charged rhodamine 123, negatively charged fluorescein, and neutral rhodamine 110. Temporal peak widths for the three dyes ranged from 3 to 7 s and did not change significantly with increasing transit distance. Moderate adsorption was observed for Chromeo P503-labeled myoglobin and cytochrome c with temporal peak widths around 20 s. Overall, the COC surface adsorption was low compared to traditional glass devices, where peak widths are on the order of minutes. Improvements in durability, long-term performance, and ease of fabrication, combined with low overall adsorption, make the COC μFFE devices a practical choice for applications involving time-resolved continuous detection.
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Affiliation(s)
- Cecilia
C. Douma
- Department of Chemistry, University
of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States
| | - Michael T. Bowser
- Department of Chemistry, University
of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States
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2
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Zhang A, Xu J, Li X, Lin Z, Song Y, Li X, Wang Z, Cheng Y. High-Throughput Continuous-Flow Separation in a Micro Free-Flow Electrophoresis Glass Chip Based on Laser Microfabrication. SENSORS (BASEL, SWITZERLAND) 2022; 22:1124. [PMID: 35161869 PMCID: PMC8838507 DOI: 10.3390/s22031124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Revised: 01/20/2022] [Accepted: 01/28/2022] [Indexed: 06/14/2023]
Abstract
Micro free-flow electrophoresis (μFFE) provides a rapid and straightforward route for the high-performance online separation and purification of targeted liquid samples in a mild manner. However, the facile fabrication of a μFFE device with high throughput and high stability remains a challenge due to the technical barriers of electrode integration and structural design for the removal of bubbles for conventional methods. To address this, the design and fabrication of a high-throughput μFFE chip are proposed using laser-assisted chemical etching of glass followed by electrode integration and subsequent low-temperature bonding. The careful design of the height ratio of the separation chamber and electrode channels combined with a high flow rate of buffer solution allows the efficient removal of electrolysis-generated bubbles along the deep electrode channels during continuous-flow separation. The introduction of microchannel arrays further enhances the stability of on-chip high-throughput separation. As a proof-of-concept, high-performance purification of fluorescein sodium solution with a separation purity of ~97.9% at a voltage of 250 V from the mixture sample solution of fluorescein sodium and rhodamine 6G solution is demonstrated.
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Affiliation(s)
- Aodong Zhang
- Engineering Research Center for Nanophotonics and Advanced Instrument, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China; (A.Z.); (Z.W.); (Y.C.)
- State Key Laboratory of Precision Spectroscopy, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China; (X.L.); (Z.L.); (Y.S.)
- XXL—The Extreme Optoelectromechanics Laboratory, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China
| | - Jian Xu
- Engineering Research Center for Nanophotonics and Advanced Instrument, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China; (A.Z.); (Z.W.); (Y.C.)
- State Key Laboratory of Precision Spectroscopy, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China; (X.L.); (Z.L.); (Y.S.)
- XXL—The Extreme Optoelectromechanics Laboratory, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China
| | - Xiaolong Li
- State Key Laboratory of Precision Spectroscopy, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China; (X.L.); (Z.L.); (Y.S.)
- XXL—The Extreme Optoelectromechanics Laboratory, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China
| | - Zijie Lin
- State Key Laboratory of Precision Spectroscopy, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China; (X.L.); (Z.L.); (Y.S.)
- XXL—The Extreme Optoelectromechanics Laboratory, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China
| | - Yunpeng Song
- State Key Laboratory of Precision Spectroscopy, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China; (X.L.); (Z.L.); (Y.S.)
- XXL—The Extreme Optoelectromechanics Laboratory, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China
| | - Xin Li
- Engineering Research Center for Nanophotonics and Advanced Instrument, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China; (A.Z.); (Z.W.); (Y.C.)
| | - Zhenhua Wang
- Engineering Research Center for Nanophotonics and Advanced Instrument, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China; (A.Z.); (Z.W.); (Y.C.)
- State Key Laboratory of Precision Spectroscopy, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China; (X.L.); (Z.L.); (Y.S.)
- XXL—The Extreme Optoelectromechanics Laboratory, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China
| | - Ya Cheng
- Engineering Research Center for Nanophotonics and Advanced Instrument, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China; (A.Z.); (Z.W.); (Y.C.)
- State Key Laboratory of Precision Spectroscopy, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China; (X.L.); (Z.L.); (Y.S.)
- XXL—The Extreme Optoelectromechanics Laboratory, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
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3
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Jender M, Höving S, Novo P, Freier E, Janasek D. Coupling Miniaturized Free-Flow Electrophoresis to Mass Spectrometry via a Multi-Emitter ESI Interface. Anal Chem 2021; 93:7204-7209. [PMID: 33939916 DOI: 10.1021/acs.analchem.1c00200] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We present a novel multi-emitter electrospray ionization (ESI) interface for the coupling of microfluidic free-flow electrophoresis (μFFE) with mass spectrometry (MS). The effluents of the μFFE outlets are analyzed in near real-time, allowing a direct optimization of the electrophoretic separation and an online monitoring of qualitative sample compositions. The short measurement time of just a few seconds for all outlets even enables a reasonable time-dependent monitoring. As a proof of concept, we employ the multi-emitter ESI interface for the continuous identification of analytes at 15 μFFE outlets via MS to optimize the μFFE separation of important players of cellular respiration in operando. The results indicate great potential of the presented system in downstream processing control, for example, for the monitoring and purification of products in continuous-flow microreactors.
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Affiliation(s)
- Matthias Jender
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V., Bunsen-Kirchhoff-Str. 11, 44139 Dortmund, Germany
| | - Stefan Höving
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V., Bunsen-Kirchhoff-Str. 11, 44139 Dortmund, Germany
| | - Pedro Novo
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V., Bunsen-Kirchhoff-Str. 11, 44139 Dortmund, Germany
| | - Erik Freier
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V., Bunsen-Kirchhoff-Str. 11, 44139 Dortmund, Germany
| | - Dirk Janasek
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V., Bunsen-Kirchhoff-Str. 11, 44139 Dortmund, Germany
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4
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Xie Y, Rufo J, Zhong R, Rich J, Li P, Leong KW, Huang TJ. Microfluidic Isolation and Enrichment of Nanoparticles. ACS NANO 2020; 14:16220-16240. [PMID: 33252215 PMCID: PMC8164652 DOI: 10.1021/acsnano.0c06336] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Over the past decades, nanoparticles have increased in implementation to a variety of applications ranging from high-efficiency electronics to targeted drug delivery. Recently, microfluidic techniques have become an important tool to isolate and enrich populations of nanoparticles with uniform properties (e.g., size, shape, charge) due to their precision, versatility, and scalability. However, due to the large number of microfluidic techniques available, it can be challenging to identify the most suitable approach for isolating or enriching a nanoparticle of interest. In this review article, we survey microfluidic methods for nanoparticle isolation and enrichment based on their underlying mechanisms, including acoustofluidics, dielectrophoresis, filtration, deterministic lateral displacement, inertial microfluidics, optofluidics, electrophoresis, and affinity-based methods. We discuss the principles, applications, advantages, and limitations of each method. We also provide comparisons with bulk methods, perspectives for future developments and commercialization, and next-generation applications in chemistry, biology, and medicine.
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Affiliation(s)
- Yuliang Xie
- Roy J. Carver Department of Biomedical Engineering, University of Iowa, Iowa City, Iowa 52242, United States
| | - Joseph Rufo
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina 27708, United States
| | - Ruoyu Zhong
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina 27708, United States
| | - Joseph Rich
- Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708, United States
| | - Peng Li
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia 26506, United States
| | - Kam W Leong
- Department of Biomedical Engineering, Columbia University, New York, New York 10032, United States
| | - Tony Jun Huang
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina 27708, United States
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5
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Li H, Li F, Zhao L, Zhao L, Sun P, Wu J, Wang X, Pu Q. Electric Field-Driven On-Request Instant in Situ Formation/Removal of Solid Hydrogel within Microchannels for Efficient Electrophoretic Separation. ACS APPLIED MATERIALS & INTERFACES 2020; 12:8773-8779. [PMID: 31997635 DOI: 10.1021/acsami.9b22878] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Electrophoretic separation in short microchannels is a promising way for rapid analysis of biomolecules, but the pressurized laminar flow may compromise the separation efficiency. In this work, through an electric field, instant formation and removal of a solid chitosan/β-glycerol phosphate (CS/β-GP) hydrogel within microchannels of microchips were realized. In a typical cross-type microchip, the CS/β-GP hydrogel was precisely formed in the separation microchannel within 15 s of the application of a voltage of 2000 V. Highly efficient separation of peptides and proteins was achieved, and theoretical plate numbers of 0.6 to 1.5 × 106/m were attained for proteins in 120 s. The used hydrogel could be swiftly removed also with an electric field, and the whole procedure was achieved on a standard microchip electrophoresis device with no extra accessory or special operation required.
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Affiliation(s)
- Hongli Li
- State Key Laboratory of Applied Organic Chemistry, Key Laboratory of Nonferrous Metals Chemistry and Resources Utilization of Gansu Province, Department of Chemistry , Lanzhou University , Lanzhou , Gansu 730000 , China
| | - Fengyun Li
- State Key Laboratory of Applied Organic Chemistry, Key Laboratory of Nonferrous Metals Chemistry and Resources Utilization of Gansu Province, Department of Chemistry , Lanzhou University , Lanzhou , Gansu 730000 , China
| | - Lizhi Zhao
- State Key Laboratory of Applied Organic Chemistry, Key Laboratory of Nonferrous Metals Chemistry and Resources Utilization of Gansu Province, Department of Chemistry , Lanzhou University , Lanzhou , Gansu 730000 , China
| | - Lei Zhao
- State Key Laboratory of Applied Organic Chemistry, Key Laboratory of Nonferrous Metals Chemistry and Resources Utilization of Gansu Province, Department of Chemistry , Lanzhou University , Lanzhou , Gansu 730000 , China
| | - Ping Sun
- State Key Laboratory of Applied Organic Chemistry, Key Laboratory of Nonferrous Metals Chemistry and Resources Utilization of Gansu Province, Department of Chemistry , Lanzhou University , Lanzhou , Gansu 730000 , China
| | - Jing Wu
- State Key Laboratory of Applied Organic Chemistry, Key Laboratory of Nonferrous Metals Chemistry and Resources Utilization of Gansu Province, Department of Chemistry , Lanzhou University , Lanzhou , Gansu 730000 , China
| | - Xiayan Wang
- Beijing Key Laboratory for Green Catalysis and Separation, Department of Chemistry and Chemical Engineering , Beijing University of Technology , Beijing 100124 , China
| | - Qiaosheng Pu
- State Key Laboratory of Applied Organic Chemistry, Key Laboratory of Nonferrous Metals Chemistry and Resources Utilization of Gansu Province, Department of Chemistry , Lanzhou University , Lanzhou , Gansu 730000 , China
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6
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Anciaux SK, Bowser MT. Reduced surface adsorption in 3D printed acrylonitrile butadiene styrene micro free-flow electrophoresis devices. Electrophoresis 2020; 41:225-234. [PMID: 31816114 PMCID: PMC7316087 DOI: 10.1002/elps.201900179] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2019] [Revised: 12/03/2019] [Accepted: 12/04/2019] [Indexed: 01/27/2023]
Abstract
We have 3D printed and fabricated micro free-flow electrophoresis (µFFE) devices in acrylonitrile butadiene styrene (ABS) that exhibit minimal surface adsorption without requiring additional surface coatings or specialized buffer additives. 2D, nano LC-micro free flow electrophoresis (2D nLC × µFFE) separations were used to assess both spatial and temporal broadening as peaks eluted through the separation channel. Minimal broadening due to wall adsorption was observed in either the spatial or temporal dimensions during separations of rhodamine 110, rhodamine 123, and fluorescein. Surface adsorption was observed in separations of Chromeo P503 labeled myoglobin and cytochrome c but was significantly reduced compared to previously reported glass devices. Peak widths of < 30 s were observed for both proteins. For comparison, Chromeo P503 labeled myoglobin and cytochrome c adsorb strongly to the surface of glass µFFE devices resulting in peak widths >20 min. A 2D nLC × µFFE separation of a Chromeo P503 labeled tryptic digest of BSA was performed to demonstrate the high peak capacity possible due to the low surface adsorption in the 3D printed ABS devices, even in the absence of surface coatings or buffer additives.
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Affiliation(s)
- Sarah K. Anciaux
- University of Minnesota, Department of Chemistry, 207 Pleasant St. SE, Minneapolis, MN, 55455
| | - Michael T. Bowser
- University of Minnesota, Department of Chemistry, 207 Pleasant St. SE, Minneapolis, MN, 55455
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7
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Ivanov NA, Liu Y, Kochmann S, Krylov SN. Non-aqueous continuous-flow electrophoresis (NACFE): potential separation complement for continuous-flow organic synthesis. LAB ON A CHIP 2019; 19:2156-2160. [PMID: 31161184 DOI: 10.1039/c9lc00460b] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
We introduce non-aqueous continuous-flow electrophoresis (NACFE) in which the electrolyte is a solution of an organic salt in an aprotic organic solvent. NACFE can maintain steady-state separation of multiple hydrophobic organic species into individual molecular streams. It is a potential separation complement for continuous-flow organic synthesis. This proof-of-concept work will serve as a justification for efforts towards making NACFE a practical tool in flow chemistry.
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Affiliation(s)
- Nikita A Ivanov
- Centre for Research on Biomolecular Interactions and Department of Chemistry, York University, Toronto, Ontario M3J 1P3, Canada.
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8
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Mikhail IE, Tehranirokh M, Gooley AA, Guijt RM, Breadmore MC. In-Syringe Electrokinetic Ampholytes Focusing Coupled with Electrospray Ionization Mass Spectrometry. Anal Chem 2019; 91:8259-8266. [DOI: 10.1021/acs.analchem.9b00942] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Ibraam E. Mikhail
- ARC Training Centre for Portable
Analytical Separation Technologies (ASTech)
- Australian Centre for Research on Separation Science (ACROSS), School of Natural Sciences (Chemistry), University of Tasmania, Private Bag 75, Hobart, Tasmania 7001, Australia
- Department of Analytical Chemistry, Faculty of Pharmacy, Mansoura University, Mansoura City 35516, Egypt
| | - Masoomeh Tehranirokh
- ARC Training Centre for Portable
Analytical Separation Technologies (ASTech)
- Trajan Scientific and Medical, Ringwood, Victoria 3134, Australia
| | - Andrew A. Gooley
- ARC Training Centre for Portable
Analytical Separation Technologies (ASTech)
- Trajan Scientific and Medical, Ringwood, Victoria 3134, Australia
| | - Rosanne M. Guijt
- ARC Training Centre for Portable
Analytical Separation Technologies (ASTech)
- Deakin University, Centre for Regional and Rural Futures, Geelong, Victoria 3220, Australia
| | - Michael C. Breadmore
- ARC Training Centre for Portable
Analytical Separation Technologies (ASTech)
- Australian Centre for Research on Separation Science (ACROSS), School of Natural Sciences (Chemistry), University of Tasmania, Private Bag 75, Hobart, Tasmania 7001, Australia
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9
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Rudisch BM, Pfeiffer SA, Geissler D, Speckmeier E, Robitzki AA, Zeitler K, Belder D. Nonaqueous Micro Free-Flow Electrophoresis for Continuous Separation of Reaction Mixtures in Organic Media. Anal Chem 2019; 91:6689-6694. [DOI: 10.1021/acs.analchem.9b00714] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Benjamin M. Rudisch
- Institute of Analytical Chemistry, Leipzig University, Johannisallee 29, Leipzig 04103, Germany
| | - Simon A. Pfeiffer
- Institute of Analytical Chemistry, Leipzig University, Johannisallee 29, Leipzig 04103, Germany
| | - David Geissler
- Institute of Analytical Chemistry, Leipzig University, Johannisallee 29, Leipzig 04103, Germany
| | - Elisabeth Speckmeier
- Institute of Organic Chemistry, Leipzig University, Johannisallee 29, Leipzig 04103, Germany
| | - Andrea A. Robitzki
- Center for Biotechnology and Biomedicine, Leipzig University, Deutscher Platz 5, Leipzig 04103, Germany
| | - Kirsten Zeitler
- Institute of Organic Chemistry, Leipzig University, Johannisallee 29, Leipzig 04103, Germany
| | - Detlev Belder
- Institute of Analytical Chemistry, Leipzig University, Johannisallee 29, Leipzig 04103, Germany
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10
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Abstract
Micro free-flow electrophoresis (μFFE) is a continuous separation technique in which analytes are streamed through a perpendicularly applied electric field in a planar separation channel. Analyte streams are deflected laterally based on their electrophoretic mobilities as they flow through the separation channel. A number of μFFE separation modes have been demonstrated, including free zone (FZ), micellar electrokinetic chromatography (MEKC), isoelectric focusing (IEF) and isotachophoresis (ITP). Approximately 60 articles have been published since the first μFFE device was fabricated in 1994. We anticipate that recent advances in device design, detection, and fabrication, will allow μFFE to be applied to a much wider range of applications. Applications particularly well suited for μFFE analysis include continuous, real time monitoring and microscale purifications.
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Affiliation(s)
- Alexander C Johnson
- Department of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, MN 55455, USA.
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11
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Saar KL, Zhang Y, Müller T, Kumar CP, Devenish S, Lynn A, Łapińska U, Yang X, Linse S, Knowles TPJ. On-chip label-free protein analysis with downstream electrodes for direct removal of electrolysis products. LAB ON A CHIP 2017; 18:162-170. [PMID: 29192926 DOI: 10.1039/c7lc00797c] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The ability to apply highly controlled electric fields within microfluidic devices is valuable as a basis for preparative and analytical processes. A challenge encountered in the context of such approaches in conductive media, including aqueous buffers, is the generation of electrolysis products at the electrode/liquid interface which can lead to contamination, perturb fluid flows and generally interfere with the measurement process. Here, we address this challenge by designing a single layer microfluidic device architecture where the electric potential is applied outside and downstream of the microfluidic device while the field is propagated back to the chip via the use of a co-flowing highly conductive electrolyte solution that forms a stable interface at the separation region of the device. The co-flowing electrolyte ensures that all the generated electrolysis products, including Joule heat and gaseous products, are flowed away from the chip without coming into contact with the analytes while the single layer fabrication process where all the structures are defined lithographically allows producing the devices in a simple yet highly reproducible manner. We demonstrate that by allowing stable and effective application of electric fields in excess of 100 V cm-1, the described platform provides the basis for rapid separation of heterogeneous mixtures of proteins and protein complexes directly in their native buffers as well as for the simultaneous quantification of their charge states. We illustrate this by probing the interactions in a mixture of an amyloid forming protein, amyloid-β, and a molecular chaperone, Brichos, known to inhibit the process of amyloid formation. The availability of a platform for applying stable electric fields and its compatibility with single-layer soft-lithography processes opens up the possibility of separating and analysing a wide range of molecules on chip, including those with similar electrophoretic mobilities.
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Affiliation(s)
- Kadi L Saar
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK.
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12
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Novo P, Dell'Aica M, Jender M, Höving S, Zahedi RP, Janasek D. Integration of polycarbonate membranes in microfluidic free-flow electrophoresis. Analyst 2017; 142:4228-4239. [DOI: 10.1039/c7an01514c] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A general difficulty in the miniaturization of free-flow electrophoresis relates to the need to separate electrodes and separation bed compartments.
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Affiliation(s)
- Pedro Novo
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V
- 44227 Dortmund
- Germany
| | - Margherita Dell'Aica
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V
- 44227 Dortmund
- Germany
| | - Matthias Jender
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V
- 44227 Dortmund
- Germany
| | - Stefan Höving
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V
- 44227 Dortmund
- Germany
| | - René P. Zahedi
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V
- 44227 Dortmund
- Germany
| | - Dirk Janasek
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V
- 44227 Dortmund
- Germany
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13
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Geiger M, Bowser MT. Effect of Fluorescent Labels on Peptide and Amino Acid Sample Dimensionality in Two Dimensional nLC × μFFE Separations. Anal Chem 2016; 88:2177-87. [DOI: 10.1021/acs.analchem.5b03811] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Matthew Geiger
- Department of Chemistry, University of Minnesota, 207 Pleasant
Street SE, Minneapolis, Minnesota 55455, United States
| | - Michael T. Bowser
- Department of Chemistry, University of Minnesota, 207 Pleasant
Street SE, Minneapolis, Minnesota 55455, United States
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14
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Continuous particle separation using pressure-driven flow-induced miniaturizing free-flow electrophoresis (PDF-induced μ-FFE). Sci Rep 2016; 6:19911. [PMID: 26819221 PMCID: PMC4730231 DOI: 10.1038/srep19911] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Accepted: 12/21/2015] [Indexed: 12/24/2022] Open
Abstract
In this paper, we introduce pressure-driven flow-induced miniaturizing free-flow electrophoresis (PDF-induced μ-FFE), a novel continuous separation method. In our separation system, the external flow and electric field are applied to particles, such that particle movement is affected by pressure-driven flow, electroosmosis, and electrophoresis. We then analyzed the hydrodynamic drag force and electrophoretic force applied to the particles in opposite directions. Based on this analysis, micro- and nano-sized particles were separated according to their electrophoretic mobilities with high separation efficiency. Because the separation can be achieved in a simple T-shaped microchannel, without the use of internal electrodes, it offers the advantages of low-cost, simple device fabrication and bubble-free operation, compared with conventional μ-FFE methods. Therefore, we expect the proposed separation method to have a wide range of filtering/separation applications in biochemical analysis.
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15
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Geiger M, Harstad RK, Bowser MT. Effect of Surface Adsorption on Temporal and Spatial Broadening in Micro Free Flow Electrophoresis. Anal Chem 2015; 87:11682-90. [DOI: 10.1021/acs.analchem.5b02262] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Matthew Geiger
- Department of Chemistry, University of Minnesota, 207 Pleasant
Street SE, Minneapolis, Minnesota 55455, United States
| | - Rachel K. Harstad
- Department of Chemistry, University of Minnesota, 207 Pleasant
Street SE, Minneapolis, Minnesota 55455, United States
| | - Michael T. Bowser
- Department of Chemistry, University of Minnesota, 207 Pleasant
Street SE, Minneapolis, Minnesota 55455, United States
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16
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Agostino FJ, Krylov SN. Advances in steady-state continuous-flow purification by small-scale free-flow electrophoresis. Trends Analyt Chem 2015. [DOI: 10.1016/j.trac.2015.03.023] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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17
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Geiger M, Frost NW, Bowser MT. Comprehensive Multidimensional Separations of Peptides Using Nano-Liquid Chromatography Coupled with Micro Free Flow Electrophoresis. Anal Chem 2014; 86:5136-42. [DOI: 10.1021/ac500939q] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Matthew Geiger
- Department of Chemistry, University of Minnesota, 207 Pleasant
Street SE, Minneapolis, Minnesota 55455, United States
| | - Nicholas W. Frost
- Department of Chemistry, University of Minnesota, 207 Pleasant
Street SE, Minneapolis, Minnesota 55455, United States
| | - Michael T. Bowser
- Department of Chemistry, University of Minnesota, 207 Pleasant
Street SE, Minneapolis, Minnesota 55455, United States
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Lee HY, Barber C, Minerick AR. Improving electrokinetic microdevice stability by controlling electrolysis bubbles. Electrophoresis 2014; 35:1782-9. [DOI: 10.1002/elps.201400013] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Revised: 03/13/2014] [Accepted: 03/14/2014] [Indexed: 11/12/2022]
Affiliation(s)
- Hwi Yong Lee
- Department of Chemical Engineering; Michigan Technological University; Houghton MI USA
| | - Cedrick Barber
- Department of Chemical Engineering; Michigan Technological University; Houghton MI USA
| | - Adrienne R. Minerick
- Department of Chemical Engineering; Michigan Technological University; Houghton MI USA
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Ion concentration polarization-based continuous separation device using electrical repulsion in the depletion region. Sci Rep 2013; 3:3483. [PMID: 24352563 PMCID: PMC6506453 DOI: 10.1038/srep03483] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Accepted: 11/15/2013] [Indexed: 12/21/2022] Open
Abstract
We proposed a novel separation method, which is the first report using ion concentration polarization (ICP) to separate particles continuously. We analyzed the electrical forces that cause the repulsion of particles in the depletion region formed by ICP. Using the electrical repulsion, micro- and nano-sized particles were separated based on their electrophoretic mobilities. Because the separation of particles was performed using a strong electric field in the depletion region without the use of internal electrodes, it offers the advantages of simple, low-cost device fabrication and bubble-free operation compared with conventional continuous electrophoretic separation methods, such as miniaturizing free-flow electrophoresis (μ-FFE). This separation device is expected to be a useful tool for separating various biochemical samples, including cells, proteins, DNAs and even ions.
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Agostino FJ, Cherney LT, Galievsky V, Krylov SN. Steady-State Continuous-Flow Purification by Electrophoresis. Angew Chem Int Ed Engl 2013; 52:7256-60. [DOI: 10.1002/anie.201300104] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2013] [Revised: 02/25/2013] [Indexed: 11/07/2022]
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Agostino FJ, Cherney LT, Galievsky V, Krylov SN. Steady-State Continuous-Flow Purification by Electrophoresis. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201300104] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Sheng Y, Bowser MT. Size selective DNA transport through a nanoporous membrane in a PDMS microfluidic device. Analyst 2012; 137:1144-51. [PMID: 22262059 DOI: 10.1039/c2an15966j] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
A microfluidic counter current dialysis device for size based purification of DNA is described. The device consists of two polydimethylsiloxane (PDMS) channels separated by a track etched polycarbonate membrane with a 50 nm pore size. Recovery of fluorescein across the membrane was compared with 10 and 80 nucleotide (nt) ssDNA to characterize the device. Recovery of all three analytes improved with decreasing flow rate. Size selectivity was observed. Greater than 2-fold selectivity between 10 nt and 80 nt ssDNA was observed at linear velocities less than 3mm s(-1). Increasing the ionic strength of the buffer increased transport across the membrane. Recovery of 80 nt ssDNA increased over 4-fold by adding 30 mM NaCl to the buffer. The effect was size dependent as 10 nt showed a smaller increase while the recovery of fluorescein was largely unaffected by increasing the ionic strength of the buffer.
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Affiliation(s)
- Yixiao Sheng
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN 55455, USA
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Ding H, Li X, Lv X, Xu J, Sun X, Zhang Z, Wang H, Deng Y. Fabrication of micro free-flow electrophoresis chip by photocurable monomer binding microfabrication technique for continuous separation of proteins and their numerical simulation. Analyst 2012; 137:4482-9. [DOI: 10.1039/c2an35535c] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Puchberger-Enengl D, Podszun S, Heinz H, Hermann C, Vulto P, Urban GA. Microfluidic concentration of bacteria by on-chip electrophoresis. BIOMICROFLUIDICS 2011; 5:44111-4411110. [PMID: 22207893 PMCID: PMC3246011 DOI: 10.1063/1.3664691] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2011] [Accepted: 10/31/2011] [Indexed: 05/04/2023]
Abstract
In this contribution, we present a system for efficient preconcentration of pathogens without affecting their viability. Development of miniaturized molecular diagnostic kits requires concentration of the sample, molecule extraction, amplification, and detection. In consequence of low analyte concentrations in real-world samples, preconcentration is a critical step within this workflow. Bacteria and viruses exhibit a negative surface charge and thus can be electrophoretically captured from a continuous flow. The concept of phaseguides was applied to define gel membranes, which enable effective and reversible collection of the target species. E. coli of the strains XL1-blue and K12 were used to evaluate the performance of the device. By suppression of the electroosmotic flow both strains were captured with efficiencies of up to 99%. At a continuous flow of 15 μl/min concentration factors of 50.17 ± 2.23 and 47.36 ± 1.72 were achieved in less than 27 min for XL1-blue and K12, respectively. These results indicate that free flow electrophoresis enables efficient concentration of bacteria and the presented device can contribute to rapid analyses of swab-derived samples.
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Jing M, Bowser MT. Isolation of DNA aptamers using micro free flow electrophoresis. LAB ON A CHIP 2011; 11:3703-9. [PMID: 21947169 PMCID: PMC3454500 DOI: 10.1039/c1lc20461k] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
A micro free flow electrophoresis (μFFE) device was used to select DNA aptamers for human immunoglobulin E (IgE). The continuous nature of μFFE allowed 1.8 × 10(14) sequences to be introduced over a period of 30 min, a 300-fold improvement in library size over capillary electrophoresis based selections (CE-SELEX). Four rounds of selection were performed within four days. Aptamers with low nM dissociation constants for IgE were identified after a single round of μFFE selection.
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Turgeon RT, Fonslow BR, Jing M, Bowser MT. Measuring aptamer equilibria using gradient micro free flow electrophoresis. Anal Chem 2010; 82:3636-41. [PMID: 20373790 PMCID: PMC2865204 DOI: 10.1021/ac902877v] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Gradient micro free flow electrophoresis (muFFE) was used to observe the equilibria of DNA aptamers with their targets (IgE or HIVRT) across a range of ligand concentrations. A continuous stream of aptamer was mixed online with an increasing concentration of target and introduced into the muFFE device, which separated ligand-aptamer complexes from the unbound aptamer. The continuous nature of muFFE allowed the equilibrium distribution of aptamer and complex to be measured at 300 discrete target concentrations within 5 min. This is a significant improvement in speed and precision over affinity capillary electrophoresis (ACE) assays. The dissociation constant of the aptamer-IgE complex was estimated to be 48 +/- 3 nM. The high coverage across the range of ligand concentrations allowed complex stoichiometries of the aptamer-HIVRT complexes to be observed. Nearly continuous observation of the equilibrium distribution from 0 to 500 nM HIVRT revealed the presence of complexes with 3:1 (aptamer/HIVRT), 2:1, and 1:1 stoichiometries.
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Affiliation(s)
- Ryan T. Turgeon
- University of Minnesota, Department of Chemistry, 207 Pleasant St. SE, Minneapolis, MN 55455, , Ph: (612)624-0873, Fax: (612)626-7541
| | - Bryan R. Fonslow
- University of Minnesota, Department of Chemistry, 207 Pleasant St. SE, Minneapolis, MN 55455, , Ph: (612)624-0873, Fax: (612)626-7541
| | - Meng Jing
- University of Minnesota, Department of Chemistry, 207 Pleasant St. SE, Minneapolis, MN 55455, , Ph: (612)624-0873, Fax: (612)626-7541
| | - Michael T. Bowser
- University of Minnesota, Department of Chemistry, 207 Pleasant St. SE, Minneapolis, MN 55455, , Ph: (612)624-0873, Fax: (612)626-7541
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