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Dang VT, Pham VS. Multiphysics analytical and numerical studies of biomolecule preconcentration utilizing ion concentration polarization: a case study of convergent microchannels. Analyst 2024; 149:2252-2271. [PMID: 38470814 DOI: 10.1039/d4an00017j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/14/2024]
Abstract
A convergent sector in microfluidic devices utilizing ion concentration polarization (ICP) can help increase the preconcentration rate and the concentration enhancement factor (CEF) of biomolecules. In this work, we present a detailed study of the nozzle-like-squeeze effect of a convergent channel on the preconcentration of biomolecules. By numerically solving coupled Nernst-Planck-Poisson-Navier-Stokes governing equations for the 2D channel model, we report the first study on the critical width of a convergent region in the channel to retain the advantage of the nozzle-like-squeeze effect in speeding up preconcentration and augmenting CEF. In addition, we investigated the impact of the location and the dimensions of a convergent sector on the mechanism of biomolecule preconcentration. The location of an ion-selective membrane was also determined to ensure that biomolecules are focused on the convergent region of the channel. Moreover, we introduce analytical studies to compare and verify simulation findings. Specifically, the formulas for the critical dimensions of a convergent channel, location of a preconcentrated biomolecule plug, and position of an ion-selective membrane are presented. Furthermore, important working parameters, including electric potentials and hydrostatic pressures, were examined to scrutinize their effect on convergent concentrators. These detailed analytical solutions and numerical simulation results are consistent with experimental observations, providing deep insights into the ICP phenomenon and the preconcentration mechanism of biomolecules in convergent microfluidic concentration devices.
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Affiliation(s)
- Van-Truong Dang
- School of Mechanical Engineering, Hanoi University of Science and Technology, Hanoi, Vietnam.
| | - Van-Sang Pham
- School of Mechanical Engineering, Hanoi University of Science and Technology, Hanoi, Vietnam.
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2
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Dang VT, Pham VS. Determination of Critical Dimensions of Microchannels to Ensure the Electrokinetic Biomolecule Preconcentration: Analytical and Numerical Studies. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:6051-6064. [PMID: 38437236 DOI: 10.1021/acs.langmuir.4c00300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/06/2024]
Abstract
Preconcentration of biomolecules based on ion concentration polarization (ICP) has been splendidly applied to various biomedical and chemical processes. However, in many circumstances, biomolecule preconcentration could not occur due to the lack of full studies on the preconcentration mechanism, especially on the effect of microchannel dimensions. In this work, we provide analytical studies on the critical dimensions (minimum and maximum) of microchannels for the preconcentration of biomolecules. These formulas are verified with the numerical results by fully solving the coupled governing equations: Poisson-Nernst-Planck and Navier-Stokes experiments with appropriate boundary conditions and assumptions. In addition, we examine the impact of operational parameters, such as electric potentials and critical external pressures, on the formation of the preconcentration. Moreover, two important results are provided for the first time, including the position of the preconcentrated biomolecule region and the concentration enhancement factor of the biomolecules. These analytical and numerical results are consistent with experimental observations and, therefore, could provide sharp insight into the mechanism of biomolecule preconcentration and give useful guidelines to better design and optimize ICP-based microfluidic preconcentration devices.
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Affiliation(s)
- Van-Truong Dang
- School of Mechanical Engineering, Hanoi University of Science and Technology, Hanoi 100000, Vietnam
| | - Van-Sang Pham
- School of Mechanical Engineering, Hanoi University of Science and Technology, Hanoi 100000, Vietnam
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3
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Dezhkam R, Amiri HA, Collins DJ, Miansari M. Continuous Submicron Particle Separation Via Vortex-Enhanced Ionic Concentration Polarization: A Numerical Investigation. MICROMACHINES 2022; 13:2203. [PMID: 36557503 PMCID: PMC9786152 DOI: 10.3390/mi13122203] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 12/06/2022] [Accepted: 12/07/2022] [Indexed: 06/17/2023]
Abstract
Separation and isolation of suspended submicron particles is fundamental to a wide range of applications, including desalination, chemical processing, and medical diagnostics. Ion concentration polarization (ICP), an electrokinetic phenomenon in micro-nano interfaces, has gained attention due to its unique ability to manipulate molecules or particles in suspension and solution. Less well understood, though, is the ability of this phenomenon to generate circulatory fluid flow, and how this enables and enhances continuous particle capture. Here, we perform a comprehensive study of a low-voltage ICP, demonstrating a new electrokinetic method for extracting submicron particles via flow-enhanced particle redirection. To do so, a 2D-FEM model solves the Poisson-Nernst-Planck equation coupled with the Navier-Stokes and continuity equations. Four distinct operational modes (Allowed, Blocked, Captured, and Dodged) were recognized as a function of the particle's charges and sizes, resulting in the capture or release from ICP-induced vortices, with the critical particle dimensions determined by appropriately tuning inlet flow rates (200-800 [µm/s]) and applied voltages (0-2.5 [V]). It is found that vortices are generated above a non-dimensional ICP-induced velocity of U*=1, which represents an equilibrium between ICP velocity and lateral flow velocity. It was also found that in the case of multi-target separation, the surface charge of the particle, rather than a particle's size, is the primary determinant of particle trajectory. These findings contribute to a better understanding of ICP-based particle separation and isolation, as well as laying the foundations for the rational design and optimization of ICP-based sorting systems.
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Affiliation(s)
- Rasool Dezhkam
- Micro+Nanosystems and Applied Biophysics Laboratory, Department of Mechanical Engineering, Babol Noshirvani University of Technology, Babol 4714873113, Iran
- Department of Cancer Medicine, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Isar 11, Babol 4713818983, Iran
- Department of Mechanical Engineering, Sharif University of Technology, Tehran 113658639, Iran
| | - Hoseyn A. Amiri
- Micro+Nanosystems and Applied Biophysics Laboratory, Department of Mechanical Engineering, Babol Noshirvani University of Technology, Babol 4714873113, Iran
- Department of Cancer Medicine, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Isar 11, Babol 4713818983, Iran
| | - David J. Collins
- Department of Biomedical Engineering, University of Melbourne, Melbourne, VIC 3010, Australia
- The Graeme Clark Institute, The University of Melbourne, Melbourne, VIC 3010, Australia
| | - Morteza Miansari
- Micro+Nanosystems and Applied Biophysics Laboratory, Department of Mechanical Engineering, Babol Noshirvani University of Technology, Babol 4714873113, Iran
- Department of Cancer Medicine, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Isar 11, Babol 4713818983, Iran
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4
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Thompson JR, Crooks RM. Electrokinetic separation techniques for studying nano- and microplastics. Chem Sci 2022; 13:12616-12624. [PMID: 36519045 PMCID: PMC9645370 DOI: 10.1039/d2sc04019k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Accepted: 10/14/2022] [Indexed: 03/07/2024] Open
Abstract
In recent years, microplastics have been found in seawater, soil, food, and even human blood and tissues. The ubiquity of microplastics is alarming, but the health and environmental impacts of microplastics are just beginning to be understood. Accordingly, sampling, separating, and quantifying exposure to microplastics to devise a total risk assessment is the focus of ongoing research. Unfortunately, traditional separation methods (i.e., size- and density-based methods) unintentionally exclude the smallest microplastics (<10 μm). Limited data about the smallest microplastics is problematic because they are likely the most pervasive and have distinct properties from their larger plastic counterparts. To that end, in this Perspective, we discuss using electrokinetic methods for separating the smallest microplastics. Specifically, we describe three methods for forming electric field gradients, discuss key results within the field for continuously separating microplastics, and lastly discuss research avenues which we deem critical for advancing electrokinetic separation platforms for targeting the smallest microplastics.
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Affiliation(s)
- Jonathan R Thompson
- Department of Chemistry and Texas Materials Institute, The University of Texas at Austin 105 E. 24th St., Stop A5300 Austin Texas 78712-1224 USA +1-512-475-8674
| | - Richard M Crooks
- Department of Chemistry and Texas Materials Institute, The University of Texas at Austin 105 E. 24th St., Stop A5300 Austin Texas 78712-1224 USA +1-512-475-8674
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5
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Thompson JR, Crooks RM. Enriching Cations Using Electric Field Gradients Generated by Bipolar Electrodes in the Absence of Buffer. ChemElectroChem 2022. [DOI: 10.1002/celc.202200251] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Jonathan R. Thompson
- Department of Chemistry and Texas Materials Institute The University of Texas at Austin 105 E. 24th St., Stop A5300 Austin Texas 78712-1224 United States
| | - Richard M. Crooks
- Department of Chemistry and Texas Materials Institute The University of Texas at Austin 105 E. 24th St., Stop A5300 Austin Texas 78712-1224 United States
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6
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Wang K, Behdani B, Silvera Batista CA. Visualization of Concentration Gradients and Colloidal Dynamics under Electrodiffusiophoresis. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:5663-5673. [PMID: 35467877 DOI: 10.1021/acs.langmuir.2c00252] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
In this work, we present an experimental study of the dynamics of charged colloids under direct currents and gradients of chemical species (electrodiffusiophoresis). In our approach, we simultaneously visualize the development of concentration polarization and the ensuing dynamics of charged colloids near electrodes. With the aid of confocal microscopy and fluorescent probes, we show that the passage of current through water confined between electrodes, separated about a hundred microns, results in significant pH gradients. Depending on the current density and initial conditions, steep pH gradients develop, thus becoming a significant factor in the behavior of charged colloids. Furthermore, we show that steep pH gradients induce the focusing of charged colloids away from both electrodes. Our results provide the experimental basis for further development of models of electrodiffusiophoresis and the design of non-equilibrium strategies for the fabrication of advanced materials.
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Affiliation(s)
- Kun Wang
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, Tennessee 37212, United States
| | - Behrouz Behdani
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, Tennessee 37212, United States
| | - Carlos A Silvera Batista
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, Tennessee 37212, United States
- Vanderbilt Institute for Nanoscale Science and Engineering, Vanderbilt University, Nashville, Tennessee 37212, United States
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7
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Jeon H, Wei M, Huang X, Yao J, Han W, Wang R, Xu X, Chen J, Sun L, Han J. Rapid and Label-Free Classification of Blood Leukocytes for Immune State Monitoring. Anal Chem 2022; 94:6394-6402. [PMID: 35416029 DOI: 10.1021/acs.analchem.2c00906] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
A fully automated and label-free sample-to-answer white blood cell (WBC) cytometry platform for rapid immune state monitoring is demonstrated. The platform integrates (1) a WBC separation process using the multidimensional double spiral (MDDS) device and (2) an imaging process where images of the separated WBCs are captured and analyzed. Using the deep-learning-based image processing technique, we analyzed the captured bright-field images to classify the WBCs into their subtypes. Furthermore, in addition to cell classification, we can detect activation-induced morphological changes in WBCs for functional immune assessment, which could allow the early detection of various diseases. The integrated platform operates in a rapid (<30 min), fully automated, and label-free manner. The platform could provide a promising solution to future point-of-care WBC diagnostics applications.
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Affiliation(s)
- Hyungkook Jeon
- Research Laboratory of Electronics, Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts 02139, United States
| | - Maoyu Wei
- Ministry of Education Key Lab of RF Circuits and Systems, Hangzhou Dianzi University, Hangzhou 310018, China
| | - Xiwei Huang
- Ministry of Education Key Lab of RF Circuits and Systems, Hangzhou Dianzi University, Hangzhou 310018, China
| | - Jiangfan Yao
- Ministry of Education Key Lab of RF Circuits and Systems, Hangzhou Dianzi University, Hangzhou 310018, China
| | - Wentao Han
- Ministry of Education Key Lab of RF Circuits and Systems, Hangzhou Dianzi University, Hangzhou 310018, China
| | - Renjie Wang
- Ministry of Education Key Lab of RF Circuits and Systems, Hangzhou Dianzi University, Hangzhou 310018, China
| | - Xuefeng Xu
- Ministry of Education Key Lab of RF Circuits and Systems, Hangzhou Dianzi University, Hangzhou 310018, China
| | - Jin Chen
- Ministry of Education Key Lab of RF Circuits and Systems, Hangzhou Dianzi University, Hangzhou 310018, China
| | - Lingling Sun
- Ministry of Education Key Lab of RF Circuits and Systems, Hangzhou Dianzi University, Hangzhou 310018, China
| | - Jongyoon Han
- Research Laboratory of Electronics, Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts 02139, United States.,Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts 02139, United States.,Department of Biological Engineering, Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts 02139, United States
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8
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Jeon H, Kwon T, Yoon J, Han J. Engineering a deformation-free plastic spiral inertial microfluidic system for CHO cell clarification in biomanufacturing. LAB ON A CHIP 2022; 22:272-285. [PMID: 34931631 DOI: 10.1039/d1lc00995h] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Inertial microfluidics has enabled many impactful high throughput applications. However, devices fabricated in soft elastomer (i.e., polydimethylsiloxane (PDMS)) suffer reliability issues due to significant deformation generated by the high pressure and flow rates in inertial microfluidics. In this paper, we demonstrated deformation-free and mass-producible plastic spiral inertial microfluidic devices for high-throughput cell separation applications. The design of deformable PDMS spiral devices was translated to their plastic version by compensating for the channel deformation in the PDMS devices, analyzed by numerical simulation and confocal imaging methods. The developed plastic spiral devices showed similar performance to their original PDMS devices for blood separation and Chinese hamster ovary (CHO) cell retention. Furthermore, using a multiplexed plastic spiral unit containing 100 spirals, we successfully demonstrated ultra-high-throughput cell clarification (at a processing rate of 1 L min-1) with a high cell-clarification efficiency of ∼99% (at the cell density changing from ∼2 to ∼10 × 106 cells mL-1). Benefitting from the continuous and clogging-free separation with an industry-level throughput, the cell clarification device could be a critical breakthrough for the production of therapeutic biologics such as antibodies or vaccines, impacting biomanufacturing in general.
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Affiliation(s)
- Hyungkook Jeon
- Research Laboratory of Electronics, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA.
| | - Taehong Kwon
- Research Laboratory of Electronics, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA.
| | - Junghyo Yoon
- Research Laboratory of Electronics, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA.
| | - Jongyoon Han
- Research Laboratory of Electronics, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA.
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA
- Department of Biological Engineering, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA
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9
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Krishnamurthy A, Anand RK. Recent advances in microscale extraction driven by ion concentration polarization. Trends Analyt Chem 2022. [DOI: 10.1016/j.trac.2022.116537] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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10
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Lee D, Choi D, Park H, Lee H, Kim SJ. Electroconvective circulating flows by asymmetric Coulombic force distribution in multiscale porous membrane. J Memb Sci 2021. [DOI: 10.1016/j.memsci.2021.119286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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11
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Yoon J, Cho Y, Kim J, Kim H, Na K, Lee JH, Chung S. Simulation and Experimental Study of Ion Concentration Polarization Induced Electroconvective Vortex and Particle Movement. MICROMACHINES 2021; 12:mi12080903. [PMID: 34442525 PMCID: PMC8401646 DOI: 10.3390/mi12080903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 07/23/2021] [Accepted: 07/26/2021] [Indexed: 11/23/2022]
Abstract
Ion concentration polarization (ICP) has been widely applied in microfluidic systems in pre-concentration, particle separation, and desalination applications. General ICP microfluidic systems have three components (i.e., source, ion-exchange, and buffer), which allow selective ion transport. Recently developed trials to eliminate one of the three components to simplify the system have suffered from decreased performance by the accumulation of unwanted ions. In this paper, we presented a new ICP microfluidic system with only an ion-exchange membrane-coated channel. Numerical investigation on hydrodynamic flow and electric fields with a series of coupled governing equations enabled a strong correlation to experimental investigations on electroconvective vortices and the trajectory of charged particles. This study has significant implications for the development and optimization of ICP microfluidic and electrochemical systems for biomarker concentration and separation to improve sensing reliability and detection limits in analytic chemistry.
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Affiliation(s)
- Junghyo Yoon
- School of Mechanical Engineering, Korea University, 145 Anam-ro, Seoungbuk-gu, Seoul 02841, Korea; (J.Y.); (J.K.); (H.K.); (K.N.)
| | - Youngkyu Cho
- Department of IT Convergence, Korea University, 145 Anam-ro, Seoungbuk-gu, Seoul 02841, Korea;
- Smart Device Team, Samsung Research, Samsung Electronics Co., Seoul R&D Campus, 34 Seoungchon-gil, Seocho-gu, Seoul 06765, Korea
| | - Jaehoon Kim
- School of Mechanical Engineering, Korea University, 145 Anam-ro, Seoungbuk-gu, Seoul 02841, Korea; (J.Y.); (J.K.); (H.K.); (K.N.)
| | - Hyunho Kim
- School of Mechanical Engineering, Korea University, 145 Anam-ro, Seoungbuk-gu, Seoul 02841, Korea; (J.Y.); (J.K.); (H.K.); (K.N.)
| | - Kyuhwan Na
- School of Mechanical Engineering, Korea University, 145 Anam-ro, Seoungbuk-gu, Seoul 02841, Korea; (J.Y.); (J.K.); (H.K.); (K.N.)
- Absology Co., Ltd., Anyang 14057, Korea
| | - Jeong Hoon Lee
- Department of Electrical Engineering, Kwangwoon University, 20 Kwangwoon-ro, Nowon-gu, Seoul 01897, Korea
- Correspondence: (J.H.L.); (S.C.)
| | - Seok Chung
- School of Mechanical Engineering, Korea University, 145 Anam-ro, Seoungbuk-gu, Seoul 02841, Korea; (J.Y.); (J.K.); (H.K.); (K.N.)
- Absology Co., Ltd., Anyang 14057, Korea
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Korea
- Correspondence: (J.H.L.); (S.C.)
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12
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Chen YZ, Niu BS, Ji B, Fang F, Guo XL, Wu ZY. Salty Biofluidic Sample Clean-Up and Preconcentration with a Paper-Based Ion Concentration Polarization Interface. Anal Chem 2021; 93:10236-10242. [PMID: 34269555 DOI: 10.1021/acs.analchem.1c01640] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Charged species from complex media could be separated and enriched taking advantage of ion concentration polarization (ICP) effect; thus, ICP can be used for sample purification and improvement of detection sensitivity. In this paper, a novel and reliable ICP interface was established on a paper-based analytical device (PAD) by using ion exchange membrane, and electrokinetic stacking of target analytes from salty media was successfully demonstrated. Steady ICP effect was well observed in aqueous solution with up to 400 mM NaCl as shown by a fluorescent probe, which makes it possible to directly process salty physiological samples such as blood and urine with this type of PAD. Application of this method was demonstrated by direct online stacking of total protein from urine samples and image-based colorimetric detection by a smartphone camera. The linear response was in the range of 50-350 mg/L (R2 = 0.99), with recovery rate in the range of 94.8-107.6% and relative standard deviation below 7.1%. The obtained results were consistent with that of the clinical method. As an off-line sample pretreatment method, the feasibility for rapid tandem mass spectrometry detection of amino acids from serum samples was also investigated, and promising results were obtained. This PAD method is of low cost, easy to operate, and reliable. As a disposable PAD, it is useful not only for sensitive point-of-care testing but also for direct purification and concentration of complex and highly conductive physiological samples for fast and accurate detection with advanced analytical instruments.
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Affiliation(s)
- Yu-Zhu Chen
- Research Center for Analytical Sciences, Chemistry Department, College of Sciences, Northeastern University, Shenyang 110819, China
| | - Bing-Su Niu
- Research Center for Analytical Sciences, Chemistry Department, College of Sciences, Northeastern University, Shenyang 110819, China
| | - Bin Ji
- The First Affiliated Hospital of China Medical University, Shenyang 110001, China
| | - Fang Fang
- Research Center for Analytical Sciences, Chemistry Department, College of Sciences, Northeastern University, Shenyang 110819, China
| | - Xiao-Lin Guo
- The First Affiliated Hospital of China Medical University, Shenyang 110001, China
| | - Zhi-Yong Wu
- Research Center for Analytical Sciences, Chemistry Department, College of Sciences, Northeastern University, Shenyang 110819, China
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Rapid Prototyping of a Nanoparticle Concentrator Using a Hydrogel Molding Method. Polymers (Basel) 2021; 13:polym13071069. [PMID: 33805297 PMCID: PMC8037731 DOI: 10.3390/polym13071069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 03/24/2021] [Accepted: 03/25/2021] [Indexed: 11/17/2022] Open
Abstract
Nanoparticle (NP) concentration is crucial for liquid biopsies and analysis, and various NP concentrators (NPCs) have been developed. Methods using ion concentration polarization (ICP), an electrochemical phenomenon based on NPCs consisting of microchannels, have attracted attention because samples can be non-invasively concentrated using devices with simple structures. The fabrication of such NPCs is limited by the need for lithography, requiring special equipment and time. To overcome this, we reported a rapid prototyping method for NPCs by extending the previously developed hydrogel molding method, a microchannel fabrication method using hydrogel as a mold. With this, we fabricated NPCs with both straight and branched channels, typical NPC configurations. The generation of ICP was verified, and an NP concentration test was performed using dispersions of negatively and positively charged NPs. In the straight-channel NPC, negatively and positively charged NPs were concentrated >50-fold and >25-fold the original concentration, respectively. To our knowledge, this is the first report of NP concentration via ICP in a straight-channel NPC. Using a branched-channel NPC, maximum concentration rates of 2.0-fold and 1.7-fold were obtained with negatively and positively charged NPs, respectively, similar to those obtained with NPCs fabricated through conventional lithography. This rapid prototyping method is expected to promote the development of NPCs for liquid biopsy and analysis.
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Park S, Buhnik-Rosenblau K, Abu-Rjal R, Kashi Y, Yossifon G. Periodic concentration-polarization-based formation of a biomolecule preconcentrate for enhanced biosensing. NANOSCALE 2020; 12:23586-23595. [PMID: 33210690 DOI: 10.1039/d0nr05930g] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Ionic concentration-polarization (CP)-based biomolecule preconcentration is an established method for enhancing the detection sensitivity of target biomolecules. However, the formed preconcentrated biomolecule plug rapidly sweeps over the surface-immobilized antibodies, resulting in a short-term overlap between the capture agent and the analyte, and subsequently suboptimal binding. To overcome this, we designed a setup allowing for the periodic formation of a preconcentrated biomolecule plug by activating the CP for predetermined on/off intervals. This work demonstrated the feasibility of cyclic CP actuation and optimized the sweeping conditions required to obtain the maximum retention time of a preconcentrated plug over a desired sensing region and enhanced detection sensitivity. The ability of this method to efficiently preconcentrate different analytes and to successfully increase immunoassay sensitivity underscore its potential in immunoassays serving the clinical and food testing industries.
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Affiliation(s)
- Sinwook Park
- Faculty of Mechanical Engineering, Micro- and Nanofluidics Laboratory, Technion - Israel Institute of Technology, Technion City 3200000, Israel.
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15
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Jeon H, Jundi B, Choi K, Ryu H, Levy BD, Lim G, Han J. Fully-automated and field-deployable blood leukocyte separation platform using multi-dimensional double spiral (MDDS) inertial microfluidics. LAB ON A CHIP 2020; 20:3612-3624. [PMID: 32990714 DOI: 10.1039/d0lc00675k] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
A fully-automated and portable leukocyte separation platform was developed based on a new type of inertial microfluidic device, multi-dimensional double spiral (MDDS) device, as an alternative to centrifugation. By combining key innovations in inertial microfluidic device designs and check-valve-based recirculation processes, highly purified and concentrated WBCs (up to >99.99% RBC removal, ∼80% WBC recovery, >85% WBC purity, and ∼12-fold concentrated WBCs compared to the input sample) were achieved in less than 5 minutes, with high reliability and repeatability (coefficient of variation, CV < 5%). Using this, one can harvest up to 0.4 million of intact WBCs from 50 μL of human peripheral blood (50 μL), without any cell damage or phenotypic changes in a fully-automated operation. Alternatively, hand-powered operation is demonstrated with comparable separation efficiency and speed, which eliminates the need for electricity altogether for truly field-friendly sample preparation. The proposed platform is therefore highly deployable for various point-of-care applications, including bedside assessment of the host immune response and blood sample processing in resource-limited environments.
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Affiliation(s)
- Hyungkook Jeon
- Research Laboratory of Electronics, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA. and Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk 37673, Republic of Korea
| | - Bakr Jundi
- Division of Pulmonary and Critical Care Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Kyungyong Choi
- Research Laboratory of Electronics, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA. and Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA
| | - Hyunryul Ryu
- Research Laboratory of Electronics, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA.
| | - Bruce D Levy
- Division of Pulmonary and Critical Care Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Geunbae Lim
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk 37673, Republic of Korea
| | - Jongyoon Han
- Research Laboratory of Electronics, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA. and Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA and Department of Biological Engineering, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA
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16
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Davies CD, Crooks RM. Focusing, sorting, and separating microplastics by serial faradaic ion concentration polarization. Chem Sci 2020; 11:5547-5558. [PMID: 32874498 PMCID: PMC7441690 DOI: 10.1039/d0sc01931c] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 05/13/2020] [Indexed: 12/16/2022] Open
Abstract
In this article, we report continuous sorting of two microplastics in a trifurcated microfluidic channel using a new method called serial faradaic ion concentration polarization (fICP). fICP is an electrochemical method for forming ion depletion zones and their corresponding locally elevated electric fields in microchannels. By tuning the interplay between the forces of electromigration and convection during a fICP experiment, it is possible to control the flow of charged objects in microfluidic channels. The key findings of this report are threefold. First, fICP at two bipolar electrodes, configured in series and operated with a single power supply, yields two electric field gradients within a single microfluidic channel (i.e., serial fICP). Second, complex flow variations that adversely impact separations during fICP can be mitigated by minimizing convection by electroosmotic flow in favor of pressure-driven flow. Finally, serial fICP within a trifurcated microchannel is able to continuously and quantitatively focus, sort, and separate microplastics. These findings demonstrate that multiple local electric field gradients can be generated within a single microfluidic channel by simply placing metal wires at strategic locations. This approach opens a vast range of new possibilities for implementing membrane-free separations.
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Affiliation(s)
- Collin D Davies
- Department of Chemistry and Texas Materials Institute , The University of Texas at Austin , 105 E. 24th St., Stop A5300 , Austin , Texas , 78712-1224 , USA . ; Tel: +1-512-475-8674
| | - Richard M Crooks
- Department of Chemistry and Texas Materials Institute , The University of Texas at Austin , 105 E. 24th St., Stop A5300 , Austin , Texas , 78712-1224 , USA . ; Tel: +1-512-475-8674
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17
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Abstract
Electrokinetic separation techniques in microfluidics are a powerful analytical chemistry tool, although an inherent limitation of microfluidics is their low sample throughput. In this article we report a free-flow variant of an electrokinetic focusing method, namely ion concentration polarization focusing (ICPF). The analytes flow continuously through the system via pressure driven flow while they separate and concentrate perpendicularly to the flow by ICPF. We demonstrate free flow ion concentration polarization focusing (FF-ICPF) in two operating modes, namely peak and plateau modes. Additionally, we showed the separation resolution could be improved by the use of an electrophoretic spacer. We report a concentration factor of 10 in human blood plasma in continuous flow at a flow rate of 15 μL min-1.
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Affiliation(s)
- Vasileios A Papadimitriou
- BIOS Lab on a Chip group, MESA+ Institute for Nanotechnology, Max Planck Centre for Complex Fluid Dynamics and Technical Medical Centre, University of Twente, Enschede 7500 AE, The Netherlands
| | - Loes I Segerink
- BIOS Lab on a Chip group, MESA+ Institute for Nanotechnology, Max Planck Centre for Complex Fluid Dynamics and Technical Medical Centre, University of Twente, Enschede 7500 AE, The Netherlands
| | - Jan C T Eijkel
- BIOS Lab on a Chip group, MESA+ Institute for Nanotechnology, Max Planck Centre for Complex Fluid Dynamics and Technical Medical Centre, University of Twente, Enschede 7500 AE, The Netherlands
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18
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Kim S, Kim GH, Woo H, An T, Lim G. Fabrication of a Novel Nanofluidic Device Featuring ZnO Nanochannels. ACS OMEGA 2020; 5:3144-3150. [PMID: 32118130 PMCID: PMC7045310 DOI: 10.1021/acsomega.9b02524] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Accepted: 11/27/2019] [Indexed: 06/10/2023]
Abstract
We developed a novel fabrication method for nanochannels that are easily scaled up to mass production by selectively growing zinc oxide (ZnO) nanostructures and covering using a flat PDMS surface to make hollow nanochannels. Nanochannels are used in the biotechnological and environmental fields, being employed for DNA analysis and water purification, due to their unique features of capillary-induced negative pressure and an electrical double-layer overlap. However, existing nanochannel fabrication methods are complicated, costly, and not amenable to mass production. Here, we developed a novel nanochannel fabrication method. The pillar-like dense ZnO nanostructures were grown in a solution process, which is easily applicable to mass production. The size of the fabricated ZnO nanostructures has a thickness of 30-300 nm and a diameter on the order of 102 nm, which are easily adjusted by synthesis times. The ZnO nanostructures were covered by the flat polydimethylsiloxane (PDMS) surface, and then the cracks between ZnO nanostructures served as hollow nanochannels. Because the suggested fabrication process has no thermal shrinkage, the process has higher production efficiency than existing nanochannel mass production methods based on the thermal/pressure process. The mechanical strength of the fabricated ZnO nanostructures was tested with repetitive tape peeling tests. Finally, we briefly verified the nanochannel performance by applying the nanochannel to the micro/nanofluidic system, whose performance is easily evaluated and visualized by current-voltage relation.
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Affiliation(s)
- Suhyeon Kim
- Department
of Mechanical Engineering and Department of Integrative Bioscience
and Biotechnology, Pohang University of
Science and Technology (POSTECH), 77 Cheongam-Ro, Nam-Gu, Pohang 790-784, Republic
of Korea
| | - Geon Hwee Kim
- Department
of Mechanical Engineering and Department of Integrative Bioscience
and Biotechnology, Pohang University of
Science and Technology (POSTECH), 77 Cheongam-Ro, Nam-Gu, Pohang 790-784, Republic
of Korea
| | - Hyeonsu Woo
- Department
of Mechanical Engineering and Department of Integrative Bioscience
and Biotechnology, Pohang University of
Science and Technology (POSTECH), 77 Cheongam-Ro, Nam-Gu, Pohang 790-784, Republic
of Korea
| | - Taechang An
- Department
of Mechanical Design Engineering, Andong
National University, Kyungbuk 760-749, Republic of Korea
| | - Geunbae Lim
- Department
of Mechanical Engineering and Department of Integrative Bioscience
and Biotechnology, Pohang University of
Science and Technology (POSTECH), 77 Cheongam-Ro, Nam-Gu, Pohang 790-784, Republic
of Korea
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19
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Kinde TF, Hess N, Dutta D. Enhancement in MS-based peptide detection by microfluidic free-flow zone electrophoresis. Electrophoresis 2020; 41:545-553. [PMID: 31985060 DOI: 10.1002/elps.201900321] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 01/08/2020] [Accepted: 01/10/2020] [Indexed: 01/07/2023]
Abstract
Matrix components are known to significantly alter the ionization of a target analyte in ESI-based measurements particularly when working with complex biological samples. This issue however may be alleviated by extracting the analyte of interest from the original sample into a relatively simple matrix compatible with ESI mass-spectrometric analysis. In this article, we report a microfluidic device that enables such extraction of small peptide molecules into an ESI-compatible solvent stream significantly improving both the sensitivity and reproducibility of the measurements. The reported device realizes this analyte extraction capability based on the free-flow zone electrophoretic fractionation process using a set of internal electrodes placed across the width of the analysis channel. Employing lateral electric fields and separation distances of 75 V/cm and 600 µm, respectively, efficient extraction of the model peptide human angiotensin II was demonstrated allowing a reduction in its detection limit by one to three orders of magnitude using the ESI-MS method. The noted result was obtained in our experiments both for a relatively simple specimen comprising DNA strands and angiotensin II as well as for human serum samples spiked with the same model peptide.
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Affiliation(s)
- Tristan F Kinde
- Department of Chemistry, University of Wyoming, Laramie, WY, USA
| | - Natalie Hess
- Department of Chemistry, University of Wyoming, Laramie, WY, USA
| | - Debashis Dutta
- Department of Chemistry, University of Wyoming, Laramie, WY, USA
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20
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Kim S, Ganapathysubramanian B, Anand RK. Concentration Enrichment, Separation, and Cation Exchange in Nanoliter-Scale Water-in-Oil Droplets. J Am Chem Soc 2020; 142:3196-3204. [DOI: 10.1021/jacs.9b13268] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Sungu Kim
- Department of Chemistry, Iowa State University, 1605 Gilman Hall, 2415 Osborn Drive, Ames, Iowa 50011-1021, United States
- Department of Mechanical Engineering, Iowa State University, 2043 Black Engineering, 2529 Union Drive, Ames, Iowa 50011-2030, United States
| | - Baskar Ganapathysubramanian
- Department of Mechanical Engineering, Iowa State University, 2043 Black Engineering, 2529 Union Drive, Ames, Iowa 50011-2030, United States
| | - Robbyn K. Anand
- Department of Chemistry, Iowa State University, 1605 Gilman Hall, 2415 Osborn Drive, Ames, Iowa 50011-1021, United States
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21
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Kovář P, Tichý D, Slouka Z. Effect of channel geometry on ion-concentration polarization-based preconcentration and desalination. BIOMICROFLUIDICS 2019; 13:064102. [PMID: 31700561 PMCID: PMC6824913 DOI: 10.1063/1.5124787] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Accepted: 10/11/2019] [Indexed: 06/10/2023]
Abstract
Polarization of the ion-selective systems results in the formation of ion-depleted and ion-concentrated zones in the electrolyte layers adjacent to the system. One can employ ion-concentration polarization for the removal of charged large molecules and small ions from the flowing liquid. Removal of large molecules from the flowing solution and their local accumulation is often referred to as preconcentration, removal of small ions as desalination. Here, we study the effect of the channel geometry on the removal of charged species from their water solutions experimentally. Straight, converging, and diverging channels equipped with a pair of heterogeneous cation-exchange membranes are compared in terms of their effect on preconcentration of an observable fluorescein dye and on desalination of water solution of potassium chloride. Our results show that preconcentration of the dye is not significantly affected by the channel geometry. The distance of the preconcentration band from one of the membranes was approximately the same in all tested channel geometries. The major difference was in the location of the band within the channel, when the conical channels localized the band at one of the channel walls. The straight channel showed a slightly broader range of applicable flow rates. The semibatch desalination of 0.01M KCl solution turned out to be more efficient in conical channels, which was associated with a larger volume of the channel available for the accumulation of the concentrated solution. Our results suggest that conical channels can be advantageously used in transforming the ion-concentration-polarization-based semibatch desalination into a fully continuous one.
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Affiliation(s)
- Petr Kovář
- Department of Chemical Engineering, University of Chemistry and Technology Prague, Technická 3, Prague 6 16628, Czech Republic
| | - David Tichý
- Department of Chemical Engineering, University of Chemistry and Technology Prague, Technická 3, Prague 6 16628, Czech Republic
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22
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Lin CY, Combs C, Su YS, Yeh LH, Siwy ZS. Rectification of Concentration Polarization in Mesopores Leads To High Conductance Ionic Diodes and High Performance Osmotic Power. J Am Chem Soc 2019; 141:3691-3698. [DOI: 10.1021/jacs.8b13497] [Citation(s) in RCA: 129] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Chih-Yuan Lin
- Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan
| | | | - Yen-Shao Su
- Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan
| | - Li-Hsien Yeh
- Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan
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23
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A Multiwell-Based Detection Platform with Integrated PDMS Concentrators for Rapid Multiplexed Enzymatic Assays. Sci Rep 2018; 8:10772. [PMID: 30018340 PMCID: PMC6050343 DOI: 10.1038/s41598-018-29065-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2018] [Accepted: 07/05/2018] [Indexed: 02/05/2023] Open
Abstract
We report an integrated system for accelerating assays with concentrators in a standard 12-well plate (ISAAC-12) and demonstrate its versatility for rapid detection of matrix metalloproteinase (MMP)-9 expression in the cell culture supernatant of breast cancer cell line MDA-MB-231 by accelerating the enzymatic reaction and end-point signal intensity via electrokinetic preconcentration. Using direct printing of a conductive ion-permselective polymer on a polydimethylsiloxane (PDMS) channel, the new microfluidic concentrator chip can be built without modifying the underlying substrate. Through this decoupling fabrication strategy, our microfluidic concentrator chip can easily be integrated with a standard multiwell plate, the de facto laboratory standard platform for high-throughput assays, simply by reversible bonding on the bottom of each well. It increases the reaction rate of enzymatic assays by concentrating the enzyme and the reaction product inside each well simultaneously for rapid multiplexed detection.
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24
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Mogi K. A Visualization Technique of a Unique pH Distribution around an Ion Depletion Zone in a Microchannel by Using a Dual-Excitation Ratiometric Method. MICROMACHINES 2018; 9:mi9040167. [PMID: 30424100 PMCID: PMC6187760 DOI: 10.3390/mi9040167] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Revised: 03/25/2018] [Accepted: 03/27/2018] [Indexed: 01/06/2023]
Abstract
The ion depletion zone of ion concentration polarization has a strong potential to act as an immaterial barrier, separating delicate submicron substances, including biomolecules, without causing physical damage. However, the detailed mechanisms of the barrier effect remain incompletely understood because it is difficult to visualize the linked behavior of protons, cations, anions, and charged molecules in the thin ion depletion zone. In this study, pH distribution in an ion depletion zone was measured to estimate the role of proton behavior. This was done in order to use it as a tool with good controllability for biomolecule handling in the future. As a result, a unique pH peak was observed at several micrometers distance from the microchannel wall. The position of the peak appeared to be in agreement with the boundary of the ion depletion zone. From this agreement, it is expected that the pH peak has a causal connection to the barrier effect of the ion depletion zone.
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Affiliation(s)
- Katsuo Mogi
- Molecular Profiling Research Center for Drug Discovery (Molprof), National Institute of Advanced Industrial Science and Technology (AIST), 2-4-7 Aomi, Koto-ku, Tokyo 135-0064, Japan.
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25
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Phan DT, Jin L, Wustoni S, Chen CH. Buffer-free integrative nanofluidic device for real-time continuous flow bioassays by ion concentration polarization. LAB ON A CHIP 2018; 18:574-584. [PMID: 29299579 DOI: 10.1039/c7lc01066d] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
To perform precision medicine in real-time, a sensor capable of continuously monitoring target biomolecules secreted from a patient under dynamic situations is essential. In this study, a novel portable device combining an aptamer probe and a nanofluidic component was developed, enabling the buffer-free continuous monitoring of small molecules in biological fluids. This integration is synergistic: the aptamer sensor is used to bind target biomolecules, triggering a fluorescence signal change, while the nanofluidic component is applied to achieve ion concentration polarization and convert serum into a clean buffer for aptamer signal regeneration. To demonstrate the system's versatility, we measured various adenosine triphosphate concentrations in human serum for hours with high sensitivity and specificity at minute temporal resolution. Our results demonstrate that this integrative device can be applied for the continuous measurement of target biomolecules and online signal regeneration in patient samples without the use of bulky clean buffer solutions for dynamic real-time healthcare.
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Affiliation(s)
- Dinh-Tuan Phan
- Department of Biomedical Engineering, National University of Singapore, 7 Engineering Drive 1, Singapore 117574.
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26
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Davies CD, Yoon E, Crooks RM. Continuous Redirection and Separation of Microbeads by Faradaic Ion Concentration Polarization. ChemElectroChem 2017. [DOI: 10.1002/celc.201700450] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Collin D. Davies
- Department of Chemistry and Texas Materials Institute The University of Texas at Austin 105 E. 24th St., Stop A5300 Austin, Texas 78712-1224 U.S.A
| | - Eunsoo Yoon
- Department of Chemistry and Texas Materials Institute The University of Texas at Austin 105 E. 24th St., Stop A5300 Austin, Texas 78712-1224 U.S.A
| | - Richard M. Crooks
- Department of Chemistry and Texas Materials Institute The University of Texas at Austin 105 E. 24th St., Stop A5300 Austin, Texas 78712-1224 U.S.A
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27
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Gong MM, Sinton D. Turning the Page: Advancing Paper-Based Microfluidics for Broad Diagnostic Application. Chem Rev 2017. [PMID: 28627178 DOI: 10.1021/acs.chemrev.7b00024] [Citation(s) in RCA: 329] [Impact Index Per Article: 47.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Infectious diseases are a major global health issue. Diagnosis is a critical first step in effectively managing their spread. Paper-based microfluidic diagnostics first emerged in 2007 as a low-cost alternative to conventional laboratory testing, with the goal of improving accessibility to medical diagnostics in developing countries. In this review, we examine the advances in paper-based microfluidic diagnostics for medical diagnosis in the context of global health from 2007 to 2016. The theory of fluid transport in paper is first presented. The next section examines the strategies that have been employed to control fluid and analyte transport in paper-based assays. Tasks such as mixing, timing, and sequential fluid delivery have been achieved in paper and have enabled analytical capabilities comparable to those of conventional laboratory methods. The following section examines paper-based sample processing and analysis. The most impactful advancement here has been the translation of nucleic acid analysis to a paper-based format. Smartphone-based analysis is another exciting development with potential for wide dissemination. The last core section of the review highlights emerging health applications, such as male fertility testing and wearable diagnostics. We conclude the review with the future outlook, remaining challenges, and emerging opportunities.
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Affiliation(s)
- Max M Gong
- Department of Mechanical and Industrial Engineering, University of Toronto , 5 King's College Road, Toronto, Ontario, Canada M5S 3G8.,Department of Biomedical Engineering, Wisconsin Institutes for Medical Research, University of Wisconsin-Madison , 1111 Highland Avenue, Madison, Wisconsin 53705, United States
| | - David Sinton
- Department of Mechanical and Industrial Engineering, University of Toronto , 5 King's College Road, Toronto, Ontario, Canada M5S 3G8
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28
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Electrophoresis assisted time-of-flow mass spectrometry using hollow nanomechanical resonators. Sci Rep 2017; 7:3535. [PMID: 28615653 PMCID: PMC5471201 DOI: 10.1038/s41598-017-03846-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 05/08/2017] [Indexed: 12/13/2022] Open
Abstract
This report discusses the first demonstration of electrophoresis assisted time-of-flow mass spectrometry using ‘U’ shaped hollow nanomechanical resonators (HNR). Capillary electrophoresis was coupled with the HNR based mass detection to overcome low ionic conductivity of channels embedded in the HNR preventing direct in-situ electrophoretic separation. The flow of analytes through the HNR was achieved by balancing the hydrodynamic pressure to override the electromotive force and inhibit the motion of analytes towards the anode for capillary electrophoresis. The resonance frequency shifts of the HNR vibrating around 1.5 MHz were correlated with the time of the passage of the protein bands to construct the mass spectrum. The proposed concept was demonstrated by constructing a mass spectrum of egg white proteins in the molecular weight range of 14–250 kDa. When compared to regular polyacrylamide gel electrophoresis, our method not only provides a precise and fast readout but also avoids the use of chemical staining. This study paves a new route for low-cost and on-chip mass spectrometers with ultra-miniaturized dimensions.
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29
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Kim M, Rhee H, Kang JY, Kim TS, Kwak R. Merging Ion Concentration Polarization between Juxtaposed Ion Exchange Membranes to Block the Propagation of the Polarization Zone. J Vis Exp 2017. [PMID: 28287571 DOI: 10.3791/55313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
The ion concentration polarization (ICP) phenomenon is one of the most prevailing methods to preconcentrate low-abundance biological samples. The ICP induces a noninvasive region for charged biomolecules (i.e., the ion depletion zone), and targets can be preconcentrated on this region boundary. Despite the high preconcentration performances with ICP, it is difficult to find the operating conditions of non-propagating ion depletion zones. To overcome this narrow operating window, we recently developed a new platform for spatiotemporally fixed preconcentration. Unlike preceding methods that only use ion depletion, this platform also uses the opposite polarity of the ICP (i.e., ion enrichment) to stop the propagation of the ion depletion zone. By confronting the enrichment zone with the depletion zone, the two zones merge together and stop. In this paper, we describe a detailed experimental protocol to build this spatiotemporally defined ICP platform and characterize the preconcentration dynamics of the new platform by comparing them with those of the conventional device. Qualitative ion concentration profiles and current-time responses successfully capture the different dynamics between the merged ICP and the stand-alone ICP. In contrast to the conventional one that can fix the preconcentration location at only ~5 V, the new platform can produce a target-condensed plug at a specific location in the broad ranges of operating conditions: voltage (0.5-100 V), ionic strength (1-100 mM), and pH (3.7-10.3).
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Affiliation(s)
- Minyoung Kim
- Center for BioMicrosystems, Korea Institute of Science and Technology; Department of Mechanical Engineering, Seoul National University
| | - Hyunjoon Rhee
- Center for BioMicrosystems, Korea Institute of Science and Technology; Department of Industrial Engineering, University of Illinois Urbana-Champaign
| | - Ji Yoon Kang
- Center for BioMicrosystems, Korea Institute of Science and Technology
| | - Tae Song Kim
- Center for BioMicrosystems, Korea Institute of Science and Technology
| | - Rhokyun Kwak
- Center for BioMicrosystems, Korea Institute of Science and Technology;
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30
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Salafi T, Zeming KK, Zhang Y. Advancements in microfluidics for nanoparticle separation. LAB ON A CHIP 2016; 17:11-33. [PMID: 27830852 DOI: 10.1039/c6lc01045h] [Citation(s) in RCA: 128] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Nanoparticles have been widely implemented for healthcare and nanoscience industrial applications. Thus, efficient and effective nanoparticle separation methods are essential for advancement in these fields. However, current technologies for separation, such as ultracentrifugation, electrophoresis, filtration, chromatography, and selective precipitation, are not continuous and require multiple preparation steps and a minimum sample volume. Microfluidics has offered a relatively simple, low-cost, and continuous particle separation approach, and has been well-established for micron-sized particle sorting. Here, we review the recent advances in nanoparticle separation using microfluidic devices, focusing on its techniques, its advantages over conventional methods, and its potential applications, as well as foreseeable challenges in the separation of synthetic nanoparticles and biological molecules, especially DNA, proteins, viruses, and exosomes.
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Affiliation(s)
- Thoriq Salafi
- NUS Graduate School for Integrative Sciences and Engineering, Centre for Life Sciences (CeLS), National University of Singapore, 05-01 28 Medical Drive, 117456 Singapore. and Department of Biomedical Engineering, National University of Singapore, 9 Engineering Drive 1, Block EA #03-12, 117576 Singapore
| | - Kerwin Kwek Zeming
- Department of Biomedical Engineering, National University of Singapore, 9 Engineering Drive 1, Block EA #03-12, 117576 Singapore
| | - Yong Zhang
- NUS Graduate School for Integrative Sciences and Engineering, Centre for Life Sciences (CeLS), National University of Singapore, 05-01 28 Medical Drive, 117456 Singapore. and Department of Biomedical Engineering, National University of Singapore, 9 Engineering Drive 1, Block EA #03-12, 117576 Singapore
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31
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Development of an Integrated Evaluation System for a Stretchable Strain Sensor. SENSORS 2016; 16:s16071114. [PMID: 27447639 PMCID: PMC4970157 DOI: 10.3390/s16071114] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Revised: 06/08/2016] [Accepted: 07/14/2016] [Indexed: 01/08/2023]
Abstract
Recently, much research has been focused on stretchable or flexible electronic sensors for the measurement of strain or deformation on movable and variably shaped objects. In this research, to evaluate the performance of stretchable strain sensors, we have designed an integrated evaluation system capable of simultaneously measuring the change in stress and conductance of a strain sensor. Using the designed system, we have successfully evaluated the deformation characteristics, sensing range and sensing sensitivity of a stretchable strain sensor. We believe that the developed integrated evaluation system could be a useful tool for performance evaluation of stretchable strain sensors.
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32
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Kim J, Kim HY, Lee H, Kim SJ. Pseudo 1-D Micro/Nanofluidic Device for Exact Electrokinetic Responses. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:6478-6485. [PMID: 27248856 DOI: 10.1021/acs.langmuir.6b01178] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Conventionally, a 1-D micro/nanofluidic device, whose nanochannel bridged two microchannels, was widely chosen in the fundamental electrokinetic studies; however, the configuration had intrinsic limitations of the time-consuming and labor intensive tasks of filling and flushing the microchannel due to the high fluidic resistance of the nanochannel bridge. In this work, a pseudo 1-D micro/nanofluidic device incorporating air valves at each microchannel was proposed for mitigating these limitations. High Laplace pressure formed at liquid/air interface inside the microchannels played as a virtual valve only when the electrokinetic operations were conducted. The identical electrokinetic behaviors of the propagation of ion concentration polarization layer and current-voltage responses were obtained in comparison with the conventional 1-D micro/nanofluidic device by both experiments and numerical simulations. Therefore, the suggested pseudo 1-D micro/nanofluidic device owned not only experimental conveniences but also exact electrokinetic responses.
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Affiliation(s)
- Junsuk Kim
- Department of Electrical and Computer Engineering, Seoul National University , Seoul 08826, Republic of Korea
| | - Ho-Young Kim
- Department of Mechanical and Aerospace Engineering, Seoul National University , Seoul 08826, Republic of Korea
- Institute of Advanced Machines and Design, Seoul National University , Seoul 08826, Republic of Korea
- Big Data Institute, Seoul National University , Seoul 08826, Republic of Korea
| | - Hyomin Lee
- Department of Electrical and Computer Engineering, Seoul National University , Seoul 08826, Republic of Korea
- Institute of Advanced Machines and Design, Seoul National University , Seoul 08826, Republic of Korea
| | - Sung Jae Kim
- Department of Electrical and Computer Engineering, Seoul National University , Seoul 08826, Republic of Korea
- Big Data Institute, Seoul National University , Seoul 08826, Republic of Korea
- Inter-university Semiconductor Research Center, Seoul National University , Seoul 08826, Republic of Korea
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33
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Exploring Gradients in Electrophoretic Separation and Preconcentration on Miniaturized Devices. SEPARATIONS 2016. [DOI: 10.3390/separations3020012] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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34
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Martins D, Wei X, Levicky R, Song YA. Integration of Multiplexed Microfluidic Electrokinetic Concentrators with a Morpholino Microarray via Reversible Surface Bonding for Enhanced DNA Hybridization. Anal Chem 2016; 88:3539-47. [PMID: 26916577 DOI: 10.1021/acs.analchem.5b03875] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
UNLABELLED We describe a microfluidic concentration device to accelerate the surface hybridization reaction between DNA and morpholinos (MOs) for enhanced detection. The microfluidic concentrator comprises a single polydimethylsiloxane (PDMS) microchannel onto which an ion-selective layer of conductive polymer poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) ( PEDOT PSS) was directly printed and then reversibly surface bonded onto a morpholino microarray for hybridization. Using this electrokinetic trapping concentrator, we could achieve a maximum concentration factor of ∼800 for DNA and a limit of detection of 10 nM within 15 min. In terms of the detection speed, it enabled faster hybridization by around 10-fold when compared to conventional diffusion-based hybridization. A significant advantage of our approach is that the fabrication of the microfluidic concentrator is completely decoupled from the microarray; by eliminating the need to deposit an ion-selective layer on the microarray surface prior to device integration, interfacing between both modules, the PDMS chip for electrokinetic concentration and the substrate for DNA sensing are easier and applicable to any microarray platform. Furthermore, this fabrication strategy facilitates a multiplexing of concentrators. We have demonstrated the proof-of-concept for multiplexing by building a device with 5 parallel concentrators connected to a single inlet/outlet and applying it to parallel concentration and hybridization. Such device yielded similar concentration and hybridization efficiency compared to that of a single-channel device without adding any complexity to the fabrication and setup. These results demonstrate that our concentrator concept can be applied to the development of a highly multiplexed concentrator-enhanced microarray detection system for either genetic analysis or other diagnostic assays.
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Affiliation(s)
- Diogo Martins
- Division of Engineering, New York University Abu Dhabi , P.O. Box 129188 , Abu Dhabi, United Arab Emirates
| | - Xi Wei
- Division of Engineering, New York University Abu Dhabi , P.O. Box 129188 , Abu Dhabi, United Arab Emirates.,Department of Chemical and Biomolecular Engineering, New York University Tandon School of Engineering , Brooklyn, New York 11201, United States
| | - Rastislav Levicky
- Department of Chemical and Biomolecular Engineering, New York University Tandon School of Engineering , Brooklyn, New York 11201, United States
| | - Yong-Ak Song
- Division of Engineering, New York University Abu Dhabi , P.O. Box 129188 , Abu Dhabi, United Arab Emirates.,Department of Chemical and Biomolecular Engineering, New York University Tandon School of Engineering , Brooklyn, New York 11201, United States
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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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36
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Jeon H, Kim JH, Lim G. A novel nanochannel fabrication for nanofluidic applications using synchrotron radiation via a micro patterned X-ray mask. RSC Adv 2016. [DOI: 10.1039/c6ra08657h] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Extremely long nano-sized channels were fabricated based on a novel X-ray mask fabrication method. Using the fabricated nanochannels, the generation of ion concentration polarization, a novel transport phenomenon in nanofluidics, was investigated.
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Affiliation(s)
- Hyungkook Jeon
- Department of Mechanical Engineering
- Pohang University of Science and Technology (POSTECH)
- Pohang
- The Republic of Korea
| | - Jong Hyun Kim
- Pohang Accelerator Laboratory (PAL)
- Pohang University of Science and Technology (POSTECH)
- Pohang
- The Republic of Korea
| | - Geunbae Lim
- Department of Mechanical Engineering
- Pohang University of Science and Technology (POSTECH)
- Pohang
- The Republic of Korea
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37
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Zeng Z, Yeh LH, Zhang M, Qian S. Ion transport and selectivity in biomimetic nanopores with pH-tunable zwitterionic polyelectrolyte brushes. NANOSCALE 2015; 7:17020-9. [PMID: 26415890 DOI: 10.1039/c5nr05828g] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Inspired by nature, functionalized nanopores with biomimetic structures have attracted growing interests in using them as novel platforms for applications of regulating ion and nanoparticle transport. To improve these emerging applications, we study theoretically for the first time the ion transport and selectivity in short nanopores functionalized with pH tunable, zwitterionic polyelectrolyte (PE) brushes. In addition to background salt ions, the study takes into account the presence of H(+) and OH(-) ions along with the chemistry reactions between functional groups on PE chains and protons. Due to ion concentration polarization, the charge density of PE layers is not homogeneously distributed and depends significantly on the background salt concentration, pH, grafting density of PE chains, and applied voltage bias, thereby resulting in many interesting and unexpected ion transport phenomena in the nanopore. For example, the ion selectivity of the biomimetic nanopore can be regulated from anion-selective (cation-selective) to cation-selective (anion-selective) by diminishing (raising) the solution pH when a sufficiently small grafting density of PE chains, large voltage bias, and low background salt concentration are applied.
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Affiliation(s)
- Zhenping Zeng
- School of Electronic and Optical Engineering, Nanjing University of Science and Technology, Nanjing 210094, P. R. China
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38
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Breadmore MC, Tubaon RM, Shallan AI, Phung SC, Abdul Keyon AS, Gstoettenmayr D, Prapatpong P, Alhusban AA, Ranjbar L, See HH, Dawod M, Quirino JP. Recent advances in enhancing the sensitivity of electrophoresis and electrochromatography in capillaries and microchips (2012-2014). Electrophoresis 2015; 36:36-61. [DOI: 10.1002/elps.201400420] [Citation(s) in RCA: 132] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Revised: 09/25/2014] [Accepted: 09/25/2014] [Indexed: 12/15/2022]
Affiliation(s)
- Michael C. Breadmore
- School of Physical Science; Australian Centre of Research on Separation Science, University of Tasmania; Hobart Tasmania Australia
| | - Ria Marni Tubaon
- School of Physical Science; Australian Centre of Research on Separation Science, University of Tasmania; Hobart Tasmania Australia
| | - Aliaa I. Shallan
- School of Physical Science; Australian Centre of Research on Separation Science, University of Tasmania; Hobart Tasmania Australia
| | - Sui Ching Phung
- School of Physical Science; Australian Centre of Research on Separation Science, University of Tasmania; Hobart Tasmania Australia
| | - Aemi S. Abdul Keyon
- School of Physical Science; Australian Centre of Research on Separation Science, University of Tasmania; Hobart Tasmania Australia
- Faculty of Science; Department of Chemistry, Universiti Teknologi Malaysia; Johor Malaysia
| | - Daniel Gstoettenmayr
- School of Physical Science; Australian Centre of Research on Separation Science, University of Tasmania; Hobart Tasmania Australia
| | - Pornpan Prapatpong
- Faculty of Pharmacy; Department of Pharmaceutical Chemistry, Mahidol University; Rajathevee Bangkok Thailand
| | - Ala A. Alhusban
- Faculty of Health Sciences, School of Pharmacy; Australian Centre of Research on Separation Science, University of Tasmania; Hobart Tasmania Australia
| | - Leila Ranjbar
- School of Physical Science; Australian Centre of Research on Separation Science, University of Tasmania; Hobart Tasmania Australia
| | - Hong Heng See
- School of Physical Science; Australian Centre of Research on Separation Science, University of Tasmania; Hobart Tasmania Australia
- Ibnu Sina Institute for Fundamental Science Studies; Universiti Teknologi Malaysia; Johor Malaysia
| | - Mohamed Dawod
- Department of Chemistry; University of Michigan; Ann Arbor MI USA
- Faculty of Pharmacy; Department of Analytical Chemistry, Al-Azhar University; Cairo Egypt
| | - Joselito P. Quirino
- School of Physical Science; Australian Centre of Research on Separation Science, University of Tasmania; Hobart Tasmania Australia
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39
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Phan DT, Chun Y, Nguyen NT. A continuous-flow droplet-based concentrator using ion concentration polarization. RSC Adv 2015. [DOI: 10.1039/c5ra07491f] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
We reports the continuous generation of droplets with concentrated sample conditioned ion concentration polarization.
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Affiliation(s)
- Dinh-Tuan Phan
- School of Mechanical and Aerospace Engineering
- Nanyang Technological University
- Singapore 639798
| | - Yang Chun
- School of Mechanical and Aerospace Engineering
- Nanyang Technological University
- Singapore 639798
| | - Nam-Trung Nguyen
- Queensland Micro- and Nanotechnology Centre
- Griffith University
- Brisbane
- Australia
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40
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Heo J, Kwon HJ, Jeon H, Kim B, Kim SJ, Lim G. Ultra-high-aspect-orthogonal and tunable three dimensional polymeric nanochannel stack array for BioMEMS applications. NANOSCALE 2014; 6:9681-9688. [PMID: 24993028 DOI: 10.1039/c4nr00350k] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Nanofabrication technologies have been a strong advocator for new scientific fundamentals that have never been described by traditional theory, and have played a seed role in ground-breaking nano-engineering applications. In this study, we fabricated ultra-high-aspect (∼10(6) with O(100) nm nanochannel opening and O(100) mm length) orthogonal nanochannel array using only polymeric materials. Vertically aligned nanochannel arrays in parallel can be stacked to form a dense nano-structure. Due to the flexibility and stretchability of the material, one can tune the size and shape of the nanochannel using elongation and even roll the stack array to form a radial-uniformly distributed nanochannel array. The roll can be cut at discretionary lengths for incorporation with a micro/nanofluidic device. As examples, we demonstrated ion concentration polarization with the device for Ohmic-limiting/overlimiting current-voltage characteristics and preconcentrated charged species. The density of the nanochannel array was lower than conventional nanoporous membranes, such as anodic aluminum oxide membranes (AAO). However, accurate controllability over the nanochannel array dimensions enabled multiplexed one microstructure-on-one nanostructure interfacing for valuable biological/biomedical microelectromechanical system (BioMEMS) platforms, such as nano-electroporation.
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Affiliation(s)
- Joonseong Heo
- Department of Mechanical Engineering, Pohang University of Science and Technology, San 31, Pohang, Gyeongbuk, Republic of Korea.
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