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Qian J, Li H, Wang Y, Li Y, Yu J, Zhou L, Pu Q. Zwitterionic surfactant as an additive for efficient electrophoretic separation of easily absorbed rhodamine dyes on plastic microchips. J Chromatogr A 2023; 1688:463716. [PMID: 36565653 DOI: 10.1016/j.chroma.2022.463716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 12/07/2022] [Accepted: 12/09/2022] [Indexed: 12/15/2022]
Abstract
Plastic microchips possess the advantages of easy fabrication and low-cost, but their surface properties are frequently incompatible with electrophoretic separation without proper surface modification. Meanwhile, the separation microchannels on typical microchips are usually only a few centimeters long, the pressurized flow may significantly affect the electrophoretic separation if their inner diameters (id) are relatively larger (approximately > 50 μm), viscous separation medium is therefore required for efficient separation. Herein, a zwitterionic surfactant, N-hexadecyl-N,N-dimethyl-3-ammonio-1-propane sulfonate (HDAPS), was used as a multifunctional additive to inhibit the analyte adsorption, improve the surface status, control Joule heating and modulate the resolution on cyclic olefin copolymer microchips with 80 μm id, 5 cm long separation microchannels, eliminating the necessity of viscous polymeric additives. The effectiveness of HDAPS was compared with an ionic polymeric additive, poly(diallydimethylammonium chloride). The streaming potential and electroosmotic flow measurements indicated an effective inhibition of the adsorption of rhodamine B and a stable negative surface charge with zwitterionic HDAPS. Using 15 mmol/L HDAPS, 40% (v/v) methanol, and 10 mmol/L boric acid (pH 3.2) as the running buffer, rapid separation of four rhodamines was achieved within 90 s under a separation electric field of 520 V/cm. The theoretical plate numbers were in a range of 5.0×105-6.9×105/m. The relative standard deviations were no more than 0.9% for retention time and 1.5% for peak area. The proposed system was verified by the determination of rhodamines in eyeshadow and wolfberry, with standard recoveries in a range of 98.2%-101.4%.
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Affiliation(s)
- Jiali Qian
- 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
| | - 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
| | - Yuanhang Wang
- 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
| | - Yixuan 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
| | - Jie Yu
- 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 Zhou
- 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.
| | - 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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Inagawa A, Fukuyama M, Hibara A, Harada M, Okada T. Zeta potential determination with a microchannel fabricated in solidified solvents. J Colloid Interface Sci 2018; 532:231-235. [DOI: 10.1016/j.jcis.2018.07.137] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 07/28/2018] [Accepted: 07/30/2018] [Indexed: 10/28/2022]
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Schroeder TBH, Houghtaling J, Wilts BD, Mayer M. It's Not a Bug, It's a Feature: Functional Materials in Insects. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2018; 30:e1705322. [PMID: 29517829 DOI: 10.1002/adma.201705322] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 11/15/2017] [Indexed: 05/25/2023]
Abstract
Over the course of their wildly successful proliferation across the earth, the insects as a taxon have evolved enviable adaptations to their diverse habitats, which include adhesives, locomotor systems, hydrophobic surfaces, and sensors and actuators that transduce mechanical, acoustic, optical, thermal, and chemical signals. Insect-inspired designs currently appear in a range of contexts, including antireflective coatings, optical displays, and computing algorithms. However, as over one million distinct and highly specialized species of insects have colonized nearly all habitable regions on the planet, they still provide a largely untapped pool of unique problem-solving strategies. With the intent of providing materials scientists and engineers with a muse for the next generation of bioinspired materials, here, a selection of some of the most spectacular adaptations that insects have evolved is assembled and organized by function. The insects presented display dazzling optical properties as a result of natural photonic crystals, precise hierarchical patterns that span length scales from nanometers to millimeters, and formidable defense mechanisms that deploy an arsenal of chemical weaponry. Successful mimicry of these adaptations may facilitate technological solutions to as wide a range of problems as they solve in the insects that originated them.
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Affiliation(s)
- Thomas B H Schroeder
- Department of Chemical Engineering, University of Michigan, 2300 Hayward Street, Ann Arbor, MI, 48109, USA
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, 1700, Fribourg, Switzerland
| | - Jared Houghtaling
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, 1700, Fribourg, Switzerland
- Department of Biomedical Engineering, University of Michigan, 2200 Bonisteel Boulevard, Ann Arbor, MI, 48109, USA
| | - Bodo D Wilts
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, 1700, Fribourg, Switzerland
| | - Michael Mayer
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, 1700, Fribourg, Switzerland
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Ha JW. Acupuncture Injection Combined with Electrokinetic Injection for Polydimethylsiloxane Microfluidic Devices. JOURNAL OF ANALYTICAL METHODS IN CHEMISTRY 2017; 2017:7495348. [PMID: 28326222 PMCID: PMC5343277 DOI: 10.1155/2017/7495348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/15/2017] [Revised: 02/09/2017] [Accepted: 02/12/2017] [Indexed: 06/06/2023]
Abstract
We recently reported acupuncture sample injection that leads to reproducible injection of nL-scale sample segments into a polydimethylsiloxane (PDMS) microchannel for microchip capillary electrophoresis. The advantages of the acupuncture injection in microchip capillary electrophoresis include capability of minimizing sample loss and voltage control hardware and capability of introducing sample plugs into any desired position of a microchannel. However, the challenge in the previous study was to achieve reproducible, pL-scale sample injections into PDMS microchannels. In the present study, we introduce an acupuncture injection technique combined with electrokinetic injection (AICEI) technique to inject pL-scale sample segments for microchip capillary electrophoresis. We carried out the capillary zone electrophoresis (CZE) separation of FITC and fluorescein, and the mixture of 10 μM FITC and 10 μM fluorescein was separated completely by using the AICEI method.
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Affiliation(s)
- Ji Won Ha
- Department of Chemistry, University of Ulsan, 93 Daehak-Ro, Nam-Gu, Ulsan 44610, Republic of Korea
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Kumar S, Sahore V, Rogers CI, Woolley AT. Development of an integrated microfluidic solid-phase extraction and electrophoresis device. Analyst 2017; 141:1660-8. [PMID: 26820409 DOI: 10.1039/c5an02352a] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
This study focuses on the design and fabrication of a microfluidic platform that integrates solid-phase extraction (SPE) and microchip electrophoresis (μCE) on a single device. The integrated chip is a multi-layer structure consisting of polydimethylsiloxane valves with a peristaltic pump, and a porous polymer monolith in a thermoplastic layer. The valves and pump are fabricated using soft lithography to enable pressure-based fluid actuation. A porous polymer monolith column is synthesized in the SPE unit using UV photopolymerization of a mixture consisting of monomer, cross-linker, photoinitiator, and porogens. The hydrophobic, porous structure of the monolith allows protein retention with good through flow. The functionality of the integrated device in terms of pressure-controlled flow, protein retention and elution, on-chip enrichment, and separation is evaluated using ferritin (Fer). Fluorescently labeled Fer is enriched ∼80-fold on a reversed-phase monolith from an initial concentration of 100 nM. A five-valve peristaltic pump produces higher flow rates and a narrower Fer elution peak than a three-valve pump operated under similar conditions. Moreover, the preconcentration capability of the SPE unit is demonstrated through μCE of enriched Fer and two model peptides in the integrated system. FA, GGYR, and Fer are concentrated 4-, 12-, and 50-fold, respectively. The loading capacity of the polymer monolith is 56 fmol (25 ng) for Fer. This device lays the foundation for integrated systems that can be used to analyze various disease biomarkers.
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Affiliation(s)
- Suresh Kumar
- Department of Chemistry and Biochemistry, Brigham Young University, UT 84602-5700, USA.
| | - Vishal Sahore
- Department of Chemistry and Biochemistry, Brigham Young University, UT 84602-5700, USA.
| | - Chad I Rogers
- Department of Chemistry and Biochemistry, Brigham Young University, UT 84602-5700, USA.
| | - Adam T Woolley
- Department of Chemistry and Biochemistry, Brigham Young University, UT 84602-5700, USA.
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Guo J, Chen Y, Zhao L, Sun P, Li H, Zhou L, Wang X, Pu Q. A strategy to modulate the electrophoretic behavior in plastic microchips using sodium polystyrene sulfonate. J Chromatogr A 2016; 1477:132-140. [DOI: 10.1016/j.chroma.2016.11.042] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2016] [Revised: 11/21/2016] [Accepted: 11/22/2016] [Indexed: 10/20/2022]
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7
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Wei X, Sun P, Yang S, Zhao L, Wu J, Li F, Pu Q. Microchip electrophoresis with background electrolyte containing polyacrylic acid and high content organic solvent in cyclic olefin copolymer microchips for easily adsorbed dyes. J Chromatogr A 2016; 1457:144-50. [DOI: 10.1016/j.chroma.2016.06.044] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 06/12/2016] [Accepted: 06/15/2016] [Indexed: 01/15/2023]
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8
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Li H, Zhao M, Liu W, Chu W, Guo Y. Polydimethylsiloxane microfluidic chemiluminescence immunodevice with the signal amplification strategy for sensitive detection of human immunoglobin G. Talanta 2016; 147:430-6. [DOI: 10.1016/j.talanta.2015.10.018] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 10/01/2015] [Accepted: 10/06/2015] [Indexed: 10/22/2022]
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Ali I, Alharbi OML, Marsin Sanagi M. Nano-capillary electrophoresis for environmental analysis. ENVIRONMENTAL CHEMISTRY LETTERS 2015; 14:79-98. [PMID: 32214934 PMCID: PMC7087629 DOI: 10.1007/s10311-015-0547-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Accepted: 12/11/2015] [Indexed: 06/10/2023]
Abstract
Many analytical techniques have been used to monitor environmental pollutants. But most techniques are not capable to detect pollutants at nanogram levels. Hence, under such conditions, absence of pollutants is often assumed, whereas pollutants are in fact present at low but undetectable concentrations. Detection at low levels may be done by nano-capillary electrophoresis, also named microchip electrophoresis. Here, we review the analysis of pollutants by nano-capillary electrophoresis. We present instrumentations, applications, optimizations and separation mechanisms. We discuss the analysis of metal ions, pesticides, polycyclic aromatic hydrocarbons, explosives, viruses, bacteria and other contaminants. Detectors include ultraviolet-visible, fluorescent, conductivity, atomic absorption spectroscopy, refractive index, atomic fluorescence spectrometry, atomic emission spectroscopy, inductively coupled plasma, inductively coupled plasma-mass spectrometry, mass spectrometry, time-of-flight mass spectrometry and nuclear magnetic resonance. Detection limits ranged from nanogram to picogram levels.
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Affiliation(s)
- Imran Ali
- Department of Chemistry, Jamia Millia Islamia (Central University), New Delhi, 110025 India
| | - Omar M. L. Alharbi
- Biology Department, Faculty of Sciences, Taibah University, P.O. Box 30002, Madinah Al-Munawarah, 41477 Saudi Arabia
| | - Mohd. Marsin Sanagi
- Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia (UTM), 81310 Johor Bahru, Johor Malaysia
- Ibnu Sina Institute for Fundamental Science Studies, Nanotechnology Research Alliance, Universiti Teknologi Malaysia (UTM), 81310 Johor Bahru, Johor Malaysia
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Rapid determination of catecholamines in urine samples by nonaqueous microchip electrophoresis with LIF detection. Methods Mol Biol 2015; 1274:139-46. [PMID: 25673489 DOI: 10.1007/978-1-4939-2353-3_12] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Nonaqueous microchip electrophoresis (NAMCE), which makes use of an organic medium instead of a conventional aqueous buffer solution, is a promising separation method for analytical chemistry due to the enhanced solubility of hydrophobic analytes and tailored selectivity of separation. Here, we describe an NAMCE with LIF detection combined with a pump-free negative pressure sampling device for rapid determination of catecholamines (CAs) in urine samples, and the whole analysis time (including sampling time and separation time) was less than 1 min.
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Yue W, Zou H, Jin Q, Li CW, Xu T, Fu H, Tzang LC, Sun H, Zhao J, Yang M. Single layer linear array of microbeads for multiplexed analysis of DNA and proteins. Biosens Bioelectron 2014; 54:297-305. [DOI: 10.1016/j.bios.2013.10.034] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Revised: 10/16/2013] [Accepted: 10/21/2013] [Indexed: 10/26/2022]
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12
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Hu H, Li Z, Zhang X, Xu C, Guo Y. Rapid determination of catecholamines in urine samples by nonaqueous microchip electrophoresis with LIF detection. J Sep Sci 2013; 36:3419-25. [PMID: 24038935 DOI: 10.1002/jssc.201300342] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2013] [Revised: 07/11/2013] [Accepted: 08/03/2013] [Indexed: 11/06/2022]
Abstract
A method was developed for the rapid separation of catecholamines by nonaqueous microchip electrophoresis (NAMCE) with LIF detection, A homemade pump-free negative pressure sampling device was used for rapid bias-free sampling in NAMCE, the injection time was 0.5 s and the electrophoresis separation conditions were optimized. Under the optimized conditions, the samples were separated completely in <1 min. The average migration times of the epinephrine (E), dopamine (DA), and norepinephrine (NE) were 34.26, 43.81, and 50.07 s, with an RSD of 1.05, 1.26, and 0.89% (n = 7), respectively. The linearity of the method ranged from 0.0125 to 2.0 mg/L for E and 0.025~4.0 mg/L for DA and NE, with correlation coefficients ranging between 0.9978 and 0.9986. The detection limits of E, DA, and NE were 2.5, 5.0, and 5.0 μg/L, respectively. The recoveries of E, DA, and NE in spiked urine samples were between 86 and 103%, with RSDs of 4.5~6.8% (n = 5). The proposed NAMCE with LIF detection combined with a pump-free negative pressure sampling device is a simple, inexpensive, energy efficient, miniaturized system that can be successfully applied for the determination of catecholamines in urine samples.
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Affiliation(s)
- Hongmei Hu
- Key Lab of Mariculture and Enhancement of Zhejiang Province, Marine Fishery Institute of Zhejiang Province, Zhoushan, China
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Segato TP, Bhakta SA, Gordon M, Carrilho E, Willis PA, Jiao H, Garcia CD. Microfab-less Microfluidic Capillary Electrophoresis Devices. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2013; 5:1652-1657. [PMID: 23585815 PMCID: PMC3622270 DOI: 10.1039/c3ay26392d] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Compared to conventional bench-top instruments, microfluidic devices possess advantageous characteristics including great portability potential, reduced analysis time (minutes), and relatively inexpensive production, putting them on the forefront of modern analytical chemistry. Fabrication of these devices, however, often involves polymeric materials with less-than-ideal surface properties, specific instrumentation, and cumbersome fabrication procedures. In order to overcome such drawbacks, a new hybrid platform is proposed. The platform is centered on the use of 5 interconnecting microfluidic components that serve as the injector or reservoirs. These plastic units are interconnected using standard capillary tubing, enabling in-channel detection by a wide variety of standard techniques, including capacitively-coupled contactless conductivity detection (C4D). Due to the minimum impact on the separation efficiency, the plastic microfluidic components used for the experiments discussed herein were fabricated using an inexpensive engraving tool and standard Plexiglas. The presented approach (named 52-platform) offers a previously unseen versatility: enabling the assembly of the platform within minutes using capillary tubing that differs in length, diameter, or material. The advantages of the proposed design are demonstrated by performing the analysis of inorganic cations by capillary electrophoresis on soil samples from the Atacama Desert.
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Affiliation(s)
- Thiago P. Segato
- Instituto de Quimica de São Carlos, Universidade de São Paulo, São Carlos, SP, Brazil
| | - Samir A. Bhakta
- Department of Chemistry, UT San Antonio, San Antonio, TX, USA
| | - Matthew Gordon
- Department of Chemistry, UT San Antonio, San Antonio, TX, USA
| | - Emanuel Carrilho
- Instituto de Quimica de São Carlos, Universidade de São Paulo, São Carlos, SP, Brazil
| | | | - Hong Jiao
- HJ Science & Technology, Santa Clara, CA, USA
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Li R, Wang L, Gao X, Du G, Zhai H, Wang X, Guo G, Pu Q. Rapid separation and sensitive determination of banned aromatic amines with plastic microchip electrophoresis. JOURNAL OF HAZARDOUS MATERIALS 2013; 248-249:268-275. [PMID: 23385207 DOI: 10.1016/j.jhazmat.2013.01.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2012] [Revised: 12/28/2012] [Accepted: 01/08/2013] [Indexed: 06/01/2023]
Abstract
Rapid analysis of trace amount of aromatic amines in environmental samples and daily necessities has attracted considerable attentions because some of them are strongly toxic and carcinogenic. In this study, fast and efficient electrophoretic separation and sensitive determination of 5 banned aromatic amines were explored for practical analysis using disposable plastic microchips combined with a low-cost laser-induced fluorescence detector. The effect of running buffer and its additive was systematically investigated. Under the selected condition, 5 fluorescein isothiocyanate labeled aromatic amines could be baseline separated within 90s by using a 10mmol/L borate buffer containing 2% (w/v) hydroxypropyl cellulose. Calibration curves of peak areas vs. concentrations were linear up to 40 or 120μmol/L for different analytes and limits of detection were in a range of 1-3nmol/L. Theoretical plate numbers of 6.8-8.5×10(5)/m were readily achieved. The method exhibited good repeatability, relative standard deviations (n=5) of peak areas and migration times were no more than 4.6% and 0.9%, respectively. The established method was successfully applied in the quantitative analysis of these banned aromatic amines in real samples of waste water and textile, recoveries of added standards were 85-110%.
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Affiliation(s)
- Ruina 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
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15
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A study on the system of nonaqueous microchip electrophoresis with on-line peroxyoxalate chemiluminescence detection. J Sep Sci 2013; 36:713-20. [DOI: 10.1002/jssc.201200832] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2012] [Revised: 10/24/2012] [Accepted: 10/24/2012] [Indexed: 01/16/2023]
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16
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Saito RM, Coltro WKT, de Jesus DP. Instrumentation design for hydrodynamic sample injection in microchip electrophoresis: a review. Electrophoresis 2012; 33:2614-23. [PMID: 22965705 DOI: 10.1002/elps.201200089] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Reproducible and representative sample injection in microchip electrophoresis has been a bottleneck for quantitative analytical applications. Electrokinetic sample injection is the most used because it is easy to perform. However, this injection method is usually affected by sample composition and the bias effect. On the other hand, these drawbacks are overcome by the hydrodynamic (HD) sample injection, although this injection mode requires HD flow control. This review gives an overview of the basic principles, the instrumentation designs, and the performance of HD sample injection systems for microchip electrophoresis.
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Affiliation(s)
- Renata M Saito
- Institute of Chemistry, State University of Campinas, Campinas, São Paulo, Brazil
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Zhang H, Liu L, Fu X, Zhu Z. Microfluidic beads-based immunosensor for sensitive detection of cancer biomarker proteins using multienzyme-nanoparticle amplification and quantum dots labels. Biosens Bioelectron 2012. [PMID: 23202325 DOI: 10.1016/j.bios.2012.10.076] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
This study reports the development of a microfluidic beads-based immunosensor for sensitive detection of cancer biomarker α-fetoprotein (AFP) that uses multienzyme-nanoparticle amplification and quantum dots labels. This method utilizes microbeads functionalized with the capture antibodies (Ab₁) and modified electron rich proteins as sensing platform that was fabricated within a microfluidic channel, and uses gold nanoparticles (AuNPs) functionalized with the horseradish peroxidase (HRP) and the detection antibodies (Ab₂) as label. Greatly enhanced sensitivity for the cancer biomarker is based on a dual signal amplification strategy: first, the large surface area of Au nanoparticle carrier allows several binding events of HRP on each nanosphere. Enhanced sensitivity was achieved by introducing the multi-HRP-antibody functionalized AuNPs onto the surface of microbeads through "sandwich" immunoreactions and subsequently multiple biotin moieties could be deposited onto the surface of beads resulted from the oxidation of biotin-tyramine by hydrogen peroxide. Streptavidin-labeled quantum dots were then allowed to bind to the deposited biotin moieties and displayed the signal. Secondly, enhanced mass transport capability inherent from microfluidics leads to higher capture efficiency of targets because continuous flow within micro-channel delivers fresh analyte solution to the reaction site which maintains a high concentration gradient differential to enhance mass transport. Based on the dual signal amplification strategy, the developed microfluidic bead-based immunosensor could discriminate as low as 0.2 pg mL⁻¹ AFP in 10 μL of undiluted calf serum (0.2 fg/chip), and showed a 500-fold increase in detection limit compared to the off-chip test and 50-fold increase in detection limit compared to microfluidic beads-based immunoassay using single label HRP-Ab₂. The immunosensor showed acceptable repeatability and reproducibility. This microfluidic beads-based immunosensor is a promising platform for disease-related biomolecules at the lowest level at their earliest incidence.
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Affiliation(s)
- He Zhang
- School of Chemistry and Chemical Engineering, Hunan Institute of Engineering, Xiangtan 411104, People's Republic of China.
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18
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Karlinsey JM. Sample introduction techniques for microchip electrophoresis: A review. Anal Chim Acta 2012; 725:1-13. [DOI: 10.1016/j.aca.2012.02.052] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2011] [Revised: 02/25/2012] [Accepted: 02/29/2012] [Indexed: 12/24/2022]
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Wang L, Wu J, Wang Q, He C, Zhou L, Wang J, Pu Q. Rapid and sensitive determination of sulfonamide residues in milk and chicken muscle by microfluidic chip electrophoresis. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2012; 60:1613-1618. [PMID: 22277081 DOI: 10.1021/jf2036577] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
A new, rapid, and sensitive method was proposed for the determination of sulfonamide residues in milk and chicken muscle samples by microchip electrophoresis with laser-induced fluorescence detection. Separation of fluorescamine-labeled sulfonamides was accomplished by using a buffer containing 5 mmol/L boric acid and 1% (w/v) polyvinyl alcohol (PVA). The pH, amount of PVA, and concentration of boric acid in the running buffer were found to have great influence on the separation. By optimizing these conditions, the separation of four sulfonamides, sulfamethazine, sulfamethoxazole, sulfaquinoxaline, and sulfanilamide, was achieved within 1 min with limits of detection (S/N = 3) of 0.2-2.3 μg/L, which are well below the maximum residue limit. The proposed method also exhibited very good repeatability; the relative standard deviations for both within-day and between-day measurements were ≤3.0%. With a simplified sample pretreatment protocol, fast determination of sulfonamides in real samples was successfully performed with standard addition recoveries of 93.3-100.8 and 82.9-92.3%, respectively.
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Affiliation(s)
- Lili Wang
- 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, China
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Cheng H, Liu J, Yin X, Shen H, Xu Z. Elimination of suction effect in interfacing microchip electrophoresis with inductively coupled plasma mass spectrometry using porous monolithic plugs. Analyst 2012; 137:3111-8. [DOI: 10.1039/c2an35050e] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Lok KS, Kwok YC, Nguyen NT. Sample loading and retrieval by centrifugation in a closed-loop PCR microchip. Mikrochim Acta 2011. [DOI: 10.1007/s00604-011-0741-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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Multienzyme-nanoparticles amplification for sensitive virus genotyping in microfluidic microbeads array using Au nanoparticle probes and quantum dots as labels. Biosens Bioelectron 2011; 29:89-96. [DOI: 10.1016/j.bios.2011.07.074] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2011] [Accepted: 07/28/2011] [Indexed: 01/27/2023]
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23
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Sun X, Kelly RT, Danielson WF, Agrawal N, Tang K, Smith RD. Hydrodynamic injection with pneumatic valving for microchip electrophoresis with total analyte utilization. Electrophoresis 2011; 32:1610-8. [PMID: 21520147 DOI: 10.1002/elps.201000522] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2010] [Revised: 12/01/2010] [Accepted: 12/29/2010] [Indexed: 11/06/2022]
Abstract
A novel hydrodynamic injector that is directly controlled by a pneumatic valve has been developed for reproducible microchip CE separations. The PDMS devices used for the evaluation comprise a separation channel, a side channel for sample introduction, and a pneumatic valve aligned at the intersection of the channels. A low pressure (≤ 3 psi) applied to the sample reservoir is sufficient to drive sample into the separation channel. The rapidly actuated pneumatic valve enables injection of discrete sample plugs as small as ~ 100 pL for CE separation. The injection volume can be easily controlled by adjusting the intersection geometry, the solution back pressure, and the valve actuation time. Sample injection could be reliably operated at different frequencies (< 0.1 Hz to > 2 Hz) with good reproducibility (peak height relative standard deviation ≤ 3.6%) and no sampling biases associated with the conventional electrokinetic injections. The separation channel was dynamically coated with a cationic polymer, and FITC-labeled amino acids were employed to evaluate the CE separation. Highly efficient (≥ 7.0 × 10³ theoretical plates for the ~2.4-cm-long channel) and reproducible CE separations were obtained. The demonstrated method has numerous advantages compared with the conventional techniques, including repeatable and unbiased injections, little sample waste, high duty cycle, controllable injected sample volume, and fewer electrodes with no need for voltage switching. The prospects of implementing this injection method for coupling multidimensional separations for multiplexing CE separations and for sample-limited bioanalyses are discussed.
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Affiliation(s)
- Xuefei Sun
- Biological Sciences Division and Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA, USA
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24
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FENG J, YANG XJ, LI XC, YANG H, CHEN ZG. An Automated Fluid-transport Device for a Microfluidic System. ANAL SCI 2011; 27:1057-60. [DOI: 10.2116/analsci.27.1057] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Jun FENG
- School of Pharmaceutical Sciences, Sun Yat-sen University
| | - Xiu-Juan YANG
- School of Pharmaceutical Sciences, Sun Yat-sen University
| | - Xin-Chun LI
- School of Pharmaceutical Sciences, Sun Yat-sen University
| | - Hui YANG
- School of Pharmaceutical Sciences, Sun Yat-sen University
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25
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Wang X, Yin X, Cheng H, Shen H. A compact and low-cost miniaturized analysis system composed of microchip electrophoresis and chemiluminescence detection manipulated by a simple subatmospheric pressure fluid-driven device. Analyst 2010; 135:1663-71. [DOI: 10.1039/c005216g] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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26
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Hu H, Yin X, Qi L, Liu J. Pump-free and low-cost negative pressure sampling device for rapid sample loading in MCE. Electrophoresis 2009; 30:4213-8. [DOI: 10.1002/elps.200900378] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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27
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Price AK, Culbertson CT. Generation of Nonbiased Hydrodynamic Injections on Microfluidic Devices Using Integrated Dielectric Elastomer Actuators. Anal Chem 2009; 81:8942-8. [DOI: 10.1021/ac9015837] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Alexander K. Price
- Department of Chemistry, Kansas State University, 213 CBC Building, Manhattan, Kansas 66506
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28
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Oakley JA, Robinson S, Dyer CE, Greenman J, Greenway GM, Haswell SJ. Development of a gel-to-gel electro-kinetic pinched injection method for an integrated micro-fluidic based DNA analyser. Anal Chim Acta 2009; 652:239-44. [DOI: 10.1016/j.aca.2009.07.063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2009] [Revised: 07/23/2009] [Accepted: 07/24/2009] [Indexed: 10/20/2022]
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29
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Qi LY, Yin XF, Liu JH. Rapid and efficient isotachophoretic preconcentration in free solution coupled with gel electrophoresis separation on a microchip using a negative pressure sampling technique. J Chromatogr A 2009; 1216:4510-6. [DOI: 10.1016/j.chroma.2009.03.034] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2009] [Revised: 03/11/2009] [Accepted: 03/13/2009] [Indexed: 11/30/2022]
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30
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A micro-electrophoresis system based on a short capillary with hydrostatic pressure assisted separation and injection. Mikrochim Acta 2009. [DOI: 10.1007/s00604-009-0160-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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31
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Li B, Jiang L, Wang Q, Qin J, Lin B. Micropumps actuated negative pressure injection for microchip electrophoresis. Electrophoresis 2009; 29:4906-13. [PMID: 19130570 DOI: 10.1002/elps.200800336] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
A simple negative pressure pinched sample injection method was presented. This method combined diaphragm micropumps and a single voltage supply to generate controllable well-defined sample plug, and led to effective electrophoresis separation. The pinched plug was found to be favorable for obtaining representative and reproducible results that the RSD of the migration time and peak height of sodium fluorescein were 0.5 and 2.1%, respectively (n=25). The established method had been applied in separation of amino acid samples. This method has the advantages of well-defined plug, free sample bias effect, high reproducibility and convenience of controlling the negative pressure by the integrated pumps on the microchip. In addition, the single high voltage supply and the world-to-chip interface simplified the instrumentation, which is of benefit to the minimization and automation. These advantages demonstrate the potential of this method for a wide range of applications.
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Affiliation(s)
- Bowei Li
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, PR China
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32
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Lü WJ, Chen YL, Zhu JH, Chen XG. The combination of flow injection with electrophoresis using capillaries and chips. Electrophoresis 2009; 30:83-91. [DOI: 10.1002/elps.200800402] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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33
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Yang Q, Zhao YC, Xiong Q, Cheng J. Rapid chip-based capillary electrophoretic mobility shift assay with negative pressure injection for the binding study of transcription factor Abf1 inSaccharomyces cerevisiae. Electrophoresis 2008; 29:5003-9. [DOI: 10.1002/elps.200800218] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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34
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Qi LY, Yin XF, Zhang L, Wang M. Rapid and variable-volume sample loading in sieving electrophoresis microchips using negative pressure combined with electrokinetic force. LAB ON A CHIP 2008; 8:1137-1144. [PMID: 18584090 DOI: 10.1039/b800085a] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
A rapid and variable-volume sample loading scheme for chip-based sieving electrophoresis was developed by negative pressure combined with electrokinetic force. This was achieved by using a low-cost microvacuum pump and a single potential supply at a constant voltage. Both 12% linear polyacrylamide (LPA) with a high viscosity of 15000 cP and 2% hydroxyethylcellulose (HEC) with a low viscosity of 102 cP were chosen as the sieving materials to study the behavior and the versatility of the proposed method. To reduce the hydrodynamic resistance in the sampling channel, sieving material was only filled in the separation channel between the buffer waste reservoir (BW) to the edge of the crossed intersection. By applying a subambient pressure to the headspace of sample waste reservoir (SW), sample and buffer solution were drawn immediately from sample reservoir (S) and buffer reservoir (B) across the intersection to SW. At the same time, the charged sample in the sample flow was driven across the interface between the sample flow and the sieving matrix into the sieving material filled separation channel by the applied electric field. The injected sample plug length is in proportion with the loading time. Once the vacuum in SW reservoir was released to activate electrophoretic separation, flows from S and B to SW were immediately terminated by the back flow induced by the difference of the liquid levels in the reservoirs to prevent sample leakage during the separation stage. The sample consumption was about 1.7 x 10(2) nL at a loading time of 1 s for each cycle. Only 0.024 s was required to transport bias-free analyte to the injection point. It is easy to freely choose the sample plug volume in this method by simply changing the loading time and to inject high quality sample plug with non-distorted shape into the separation channel. The system has been proved to possess an exciting potential for improving throughput, repeatability, sensitivity and separation performance of chip-based sieving electrophoresis.
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Affiliation(s)
- Li-Ya Qi
- Institute of Microanalytical Systems, Department of Chemistry, Zhejiang University, Hangzhou, China
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35
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Low electroosmotic flow measurement by tilting microchip. J Chromatogr A 2008; 1194:221-4. [PMID: 18499115 DOI: 10.1016/j.chroma.2008.03.085] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2007] [Revised: 03/11/2008] [Accepted: 03/13/2008] [Indexed: 11/23/2022]
Abstract
A novel method for low electroosmotic flow (EOF) rates measurement by tilting microchip which based upon the hydrostatic pressure conception and sampling zone method is described. Sampling zone could be detected in the tilting microchip but not in non-tilting one due to the hydrostatic pressure driven. The method is fulfilled to calculate low EOF rates by detecting the liquid flow velocity driven by hydrostatic pressure, and difference between the apparent mobility of the migrating analyte in two modes is caused by the effect of hydrostatic pressure. And then the EOF rates in unknown low EOF microchip can be calculated. Different microchannels modified with bovine serum albumin (BSA), myoglobin (MB) and polyvinyl alcohol (PVA) were used to verify the method, the EOF rate value was 1.73+/-0.03, 1.21+/-0.05, 0.34+/-0.04 x 10(-4)cm(2) V(-1)s(-1), respectively. The results obtained by the proposed method were agreed well with conventional methods.
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36
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Wu D, Qin J, Lin B. Electrophoretic separations on microfluidic chips. J Chromatogr A 2008; 1184:542-59. [PMID: 18207148 PMCID: PMC7094303 DOI: 10.1016/j.chroma.2007.11.119] [Citation(s) in RCA: 148] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2007] [Revised: 11/17/2007] [Accepted: 11/30/2007] [Indexed: 02/07/2023]
Abstract
This review presents a brief outline and novel developments of electrophoretic separation in microfluidic chips. Distinct characteristics of microchip electrophoresis (MCE) are discussed first, in which sample injection plug, joule heat, channel turn, surface adsorption and modification are introduced, and some successful strategies and recognized conclusions are also included. Important achievements of microfluidic electrophoresis separation in small molecules, DNA and protein are then summarized. This review is aimed at researchers, who are interested in MCE and want to adopt MCE as a functional unit in their integrated microsystems.
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Affiliation(s)
| | - Jianhua Qin
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Bingcheng Lin
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
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37
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Wang W, Zhou F, Zhao L, Zhang JR, Zhu JJ. Improved hydrostatic pressure sample injection by tilting the microchip towards the disposable miniaturized CE device. Electrophoresis 2008; 29:561-6. [DOI: 10.1002/elps.200700207] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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38
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On-chip oligonucleotide ligation assay using one-dimensional microfluidic beads array for the detection of low-abundant DNA point mutations. Biosens Bioelectron 2008; 23:945-51. [DOI: 10.1016/j.bios.2007.09.012] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2007] [Revised: 09/07/2007] [Accepted: 09/17/2007] [Indexed: 11/17/2022]
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39
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Flow Injection Analysis–Capillary Electrophoresis. ACTA ACUST UNITED AC 2008. [DOI: 10.1016/s0166-526x(08)00611-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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40
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Zhang L, Yin X. Parallel separation of multiple samples with negative pressure sample injection on a 3-D microfluidic array chip. Electrophoresis 2007; 28:1281-8. [PMID: 17366485 DOI: 10.1002/elps.200600553] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A simple and powerful microfluidic array chip-based electrophoresis system, which is composed of a 3-D microfluidic array chip, a microvacuum pump-based negative pressure sampling device, a high-voltage supply and an LIF detector, was developed. The 3-D microfluidic array chip was fabricated with three glass plates, in which a common sample waste bus (SW(bus)) was etched in the bottom layer plate to avoid intersecting with the separation channel array. The negative pressure sampling device consists of a microvacuum air pump, a buffer vessel, a 3-way electromagnet valve, and a vacuum gauge. In the sample loading step, all the six samples and buffer solutions were drawn from their reservoirs across the injection intersections through the SW(bus) toward the common sample waste reservoir (SW(T)) by negative pressure. Only 0.5 s was required to obtain six pinched sample plugs at the channel crossings. By switching the three-way electromagnetic valve to release the vacuum in the reservoir SW(T), six sample plugs were simultaneously injected into the separation channels by EOF and electrophoretic separation was activated. Parallel separations of different analytes are presented on the 3-D array chip by using the newly developed sampling device.
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Affiliation(s)
- Lei Zhang
- Institute of Microanalytical Systems, Department of Chemistry, Zhejiang University, Hangzhou, PR China
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41
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Abstract
The history and current status of research on microfluidics in China is summarized in this review. The recent representative contributions in this field by Chinese scientists are cited. A perspective on some trends in future development of this field in China is presented.
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Affiliation(s)
- Bingcheng Lin
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, PR China.
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42
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Zhang L, Yin XF. Field amplified sample stacking coupled with chip-based capillary electrophoresis using negative pressure sample injection technique. J Chromatogr A 2006; 1137:243-8. [PMID: 17055523 DOI: 10.1016/j.chroma.2006.10.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2006] [Revised: 10/02/2006] [Accepted: 10/04/2006] [Indexed: 11/21/2022]
Abstract
A multi-T microchip for integrated field amplified sample stacking (FASS) with CE separation to increase the chip-based capillary electrophoresis (chip-based CE) sensitivity was developed. Volumetrically defined large sample plug was formed in one step within 5s by the negative pressure in headspace of the two sealed sample waste reservoirs produced using a syringe pump equipped with a 3-way valve. Stacking and separation can proceed only by switching the 3-way valve to release the vacuum in headspace of the two sample waste reservoirs. This approach considerably simplified the operations and the equipments for FASS in chip-based CE systems. Migration time precisions of 3.3% and 1.3% RSD for rhodamine123 (Rh123) and fluorescien sodium salt (Flu) in the separation of a mixture of Flu and Rh123 were obtained for nine consecutive determinations with peak height precisions of 4.8% and 3.4% RSD, respectively. Compared with the chip-based CE on the cross microchip, the sensitivity for analysis of FlTC, FITC-labeled valine (Val) and Alanine (Ala) increased 55-, 41- and 43-fold, respectively.
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Affiliation(s)
- Lei Zhang
- Institute of Microanalytical Systems, Department of Chemistry, Zhejiang University, Hangzhou 310027, China
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