1
|
Costa BMDC, Griveau S, d'Orlye F, Bedioui F, da Silva JAF, Varenne A. Microchip electrophoresis and electrochemical detection: A review on a growing synergistic implementation. Electrochim Acta 2021; 391:138928. [DOI: 10.1016/j.electacta.2021.138928] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
|
2
|
Wells SS, Dawod M, Kennedy RT. CE-MS with electrokinetic supercharging and application to determination of neurotransmitters. Electrophoresis 2019; 40:2946-2953. [PMID: 31502303 PMCID: PMC6947659 DOI: 10.1002/elps.201900203] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 09/03/2019] [Accepted: 09/05/2019] [Indexed: 12/31/2022]
Abstract
Electrokinetic supercharging (EKS) is known as one of the most effective online electrophoretic preconcentration techniques, though pairing with it with mass spectrometry has presented challenges. Here, EKS is successfully paired with ESI-MS/MS to provide a sensitive and robust method for analysis of biogenic amines in biological samples. Injection parameters including electric field strength and the buffer compositions used for the separation and focusing were investigated to achieve suitable resolution, high sensitivity, and compatibility with ESI-MS. Using EKS, the sensitivity of the method was improved 5000-fold compared to a conventional hydrodynamic injection with CZE. The separation allowed for baseline resolution of several neurotransmitters within 16 min with LODs down to 10 pM. This method was applied to targeted analysis of seven biogenic amines from rat brain stem and whole Drosophila tissue. This is the first method to use EKS with CE-ESI-MS/MS to analyze biological samples.
Collapse
Affiliation(s)
- Shane S Wells
- Department of Chemistry, University of Michigan, Ann Arbor, MI, USA
| | - Mohamed Dawod
- Department of Chemistry, University of Michigan, Ann Arbor, MI, USA
| | - Robert T Kennedy
- Department of Chemistry, University of Michigan, Ann Arbor, MI, USA
| |
Collapse
|
3
|
Hendrickx S, de Malsche W, Cabooter D. An overview of the use of microchips in electrophoretic separation techniques: fabrication, separation modes, sample preparation opportunities, and on-chip detection. Methods Mol Biol 2015; 1274:3-17. [PMID: 25673478 DOI: 10.1007/978-1-4939-2353-3_1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
This chapter is intended as a basic introduction to microchip-based capillary electrophoresis to set the scene for newcomers and give pointers to reference material. An outline of some commonly used setups and key concepts is given, many of which are explored in greater depth in later chapters.
Collapse
Affiliation(s)
- Stijn Hendrickx
- Department of Pharmaceutical and Pharmacological Sciences, Pharmaceutical Analysis, KU Leuven, O&N2 923, Herestraat 49, 3000, Leuven, Belgium
| | | | | |
Collapse
|
4
|
Deng Y, Gasilova N, Qiao L, Zhou YL, Zhang XX, Girault HH. Highly sensitive detection of five typical fluoroquinolones in low-fat milk by field-enhanced sample injection-based CE in bubble cell capillary. Electrophoresis 2014; 35:3355-62. [DOI: 10.1002/elps.201400294] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Revised: 08/05/2014] [Accepted: 08/11/2014] [Indexed: 01/19/2023]
Affiliation(s)
- Yan Deng
- Beijing National Laboratory for Molecular Sciences (BNLMS); Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education; College of Chemistry; Peking University; Beijing China
- Laboratoire d'Electrochimie Physique et Analytique; Ecole Polytechnique Fédérale de Lausanne; Lausanne Switzerland
| | - Natalia Gasilova
- Laboratoire d'Electrochimie Physique et Analytique; Ecole Polytechnique Fédérale de Lausanne; Lausanne Switzerland
| | - Liang Qiao
- Laboratoire d'Electrochimie Physique et Analytique; Ecole Polytechnique Fédérale de Lausanne; Lausanne Switzerland
| | - Ying-Lin Zhou
- Beijing National Laboratory for Molecular Sciences (BNLMS); Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education; College of Chemistry; Peking University; Beijing China
| | - Xin-Xiang Zhang
- Beijing National Laboratory for Molecular Sciences (BNLMS); Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education; College of Chemistry; Peking University; Beijing China
| | - Hubert H. Girault
- Laboratoire d'Electrochimie Physique et Analytique; Ecole Polytechnique Fédérale de Lausanne; Lausanne Switzerland
| |
Collapse
|
5
|
Lian D, Zhao S, Li J, Li B. Progress in stacking techniques based on field amplification of capillary electrophoresis. Anal Bioanal Chem 2014; 406:6129-50. [DOI: 10.1007/s00216-014-8062-7] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2014] [Revised: 07/21/2014] [Accepted: 07/22/2014] [Indexed: 02/07/2023]
|
6
|
Tu FQ, Zhang LY, Guo XF, Wang H, Zhang HS. Development of a potential method based on microchip electrophoresis with fluorescence detection for the sensitive determination of intracellular thiols in RAW264.7 cells. Electrophoresis 2014; 35:1188-95. [DOI: 10.1002/elps.201300452] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2013] [Revised: 12/06/2013] [Accepted: 12/19/2013] [Indexed: 12/14/2022]
Affiliation(s)
- Feng-Qin Tu
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education); College of Chemistry and Molecular Sciences; Wuhan University; Wuhan P. R. China
| | - Li-Yun Zhang
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education); College of Chemistry and Molecular Sciences; Wuhan University; Wuhan P. R. China
| | - Xiao-Feng Guo
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education); College of Chemistry and Molecular Sciences; Wuhan University; Wuhan P. R. China
| | - Hong Wang
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education); College of Chemistry and Molecular Sciences; Wuhan University; Wuhan P. R. China
| | - Hua-Shan Zhang
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education); College of Chemistry and Molecular Sciences; Wuhan University; Wuhan P. R. China
| |
Collapse
|
7
|
Abstract
An approach to on-capillary dual-electrode detection for CE using a parallel electrode configuration has been developed. The parallel configuration provides two operating modes. In the first mode, one working electrode is held at an oxidizing potential and the second working electrode is held at a reducing potential. This results in redox cycling of analytes between the oxidized and reduced forms, enhancing sensitivity compared to single-electrode detection. In the second mode, both working electrodes are held at different oxidizing potentials. This mode provides electrochemical characterization of electrophoretic peaks. In the redox cyclying mode, signal enhancement of up to twofold was observed for the dual-electrode detection of phenolic acid standards compared to single-electrode detection. Variation in response of less than 10% from electrode to electrode was determined (at a concentration of 60 nM) indicating reproducible fabrication. LODs were determined to be as low as 5.0 nM for dual-electrode configuration. Using the dual-potential mode peak identification of targeted phenolic acids in whiskey samples were confirmed based on both migration time and current ratios.
Collapse
Affiliation(s)
- Megan K Dorris
- Department of Chemistry, Ralph N. Adams Institute for Bioanalytical Chemistry, University of Kansas, Lawrence, KS 66047, USA
| | | | | |
Collapse
|
8
|
Guan Q, Noblitt SD, Henry CS. Electrophoretic separations in poly(dimethylsiloxane) microchips using mixtures of ionic, nonionic and zwitterionic surfactants. Electrophoresis 2012; 33:2875-83. [PMID: 23019105 PMCID: PMC3804416 DOI: 10.1002/elps.201200255] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The use of surfactant mixtures to affect both EOF and separation selectivity in electrophoresis with PDMS substrates is reported, and capacitively coupled contactless conductivity detection is introduced for EOF measurement on PDMS microchips. First, the EOF was measured for two nonionic surfactants (Tween 20 and Triton X-100), mixed ionic/nonionic surfactant systems (SDS/Tween 20 and SDS/Triton X-100), and finally for the first time, mixed zwitterionic/nonionic surfactant systems (TDAPS/Tween 20 and TDAPS/Triton X-100). EOF for the nonionic surfactants decreased with increasing surfactant concentration. The addition of SDS or TDAPS to a nonionic surfactant increased EOF. After establishing the EOF behavior, the separation of model catecholamines was explored to show the impact on separations. Similar analyte resolution with greater peak heights was achieved with mixed surfactant systems containing Tween 20 and TDAPS relative to the single surfactant system. Finally, the detection of catecholamine release from PC12 cells by stimulation with 80 mM K(+) was performed to demonstrate the usefulness of mixed surfactant systems to provide resolution of biological compounds in complex samples.
Collapse
Affiliation(s)
- Qian Guan
- Department of Chemistry, Colorado State University, Fort Collins, CO, USA
| | | | | |
Collapse
|
9
|
Abstract
This review highlights recent developments and applications of on-line sample preconcentration techniques to enhance the detection sensitivity in microchip electrophoresis (MCE); references are mainly from 2008 and later. Among various developed techniques, we focus on the sample preconcentration based on the changes in the migration velocity of analytes in two or three discontinuous solutions system, since they can provide the sensitivity enhancement with relatively easy experimental procedures and short analysis times. The characteristic features of the on-line sample preconcentration applied to microchip electrophoresis (MCE) are presented, categorized on the basis of "field strength-" or "chemically" induced changes in the migration velocity. The preconcentration techniques utilizing field strength-induced changes in the velocity include field-amplified sample stacking, isotachophoresis and transient-isotachophoresis, whereas those based on chemically induced changes in the velocity are sweeping, transient-trapping and dynamic pH junction.
Collapse
Affiliation(s)
- Fumihiko Kitagawa
- Department of Frontier Materials Chemistry, Graduate School of Science and Technology, Hirosaki University, 3 Bunkyo, Hirosaki, Aomori 036–8561, Japan.
| | | | | | | |
Collapse
|
10
|
Mark JJP, Scholz R, Matysik FM. Electrochemical methods in conjunction with capillary and microchip electrophoresis. J Chromatogr A 2012; 1267:45-64. [PMID: 22824222 DOI: 10.1016/j.chroma.2012.07.009] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2012] [Revised: 07/01/2012] [Accepted: 07/06/2012] [Indexed: 02/06/2023]
Abstract
Electromigrative techniques such as capillary and microchip electrophoresis (CE and MCE) are inherently associated with various electrochemical phenomena. The electrolytic processes occurring in the buffer reservoirs have to be considered for a proper design of miniaturized electrophoretic systems and a suitable selection of buffer composition. In addition, the control of the electroosmotic flow plays a crucial role for the optimization of CE/MCE separations. Electroanalytical methods have significant importance in the field of detection in conjunction with CE/MCE. At present, amperometric detection and contactless conductivity detection are the predominating electrochemical detection methods for CE/MCE. This paper reviews the most recent trends in the field of electrochemical detection coupled to CE/MCE. The emphasis is on methodical developments and new applications that have been published over the past five years. A rather new way for the implementation of electrochemical methods into CE systems is the concept of electrochemically assisted injection which involves the electrochemical conversions of analytes during the injection step. This approach is particularly attractive in hyphenation to mass spectrometry (MS) as it widens the range of CE-MS applications. An overview of recent developments of electrochemically assisted injection coupled to CE is presented.
Collapse
Affiliation(s)
- Jonas J P Mark
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Regensburg, Germany
| | | | | |
Collapse
|
11
|
Rattanarat P, Dungchai W, Siangproh W, Chailapakul O, Henry CS. Sodium dodecyl sulfate-modified electrochemical paper-based analytical device for determination of dopamine levels in biological samples. Anal Chim Acta 2012; 744:1-7. [PMID: 22935367 DOI: 10.1016/j.aca.2012.07.003] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Revised: 06/20/2012] [Accepted: 07/02/2012] [Indexed: 12/16/2022]
Abstract
We report the development of an electrochemical paper-based analytical device (ePAD) for the selective determination of dopamine (DA) in model serum sample. The ePAD device consists of three layers. In the top layer, SU-8 photoresist defines a hydrophilic sample application spot on the filter paper. The middle layer was made from transparency film and contained two holes, one for sample preconcentration and the other for the surfactant to allow transfer to the third layer. A screen-printed carbon electrode formed the bottom layer and was used for electrochemical measurements. In the absence of the anionic surfactant, sodium dodecyl sulfate (SDS), the oxidation peaks of DA, ascorbic acid (AA) and uric acid (UA) overlapped. With the addition of SDS, the DA oxidation peak shifted to more negative values and was clearly distinguishable from AA and UA. The oxidation potential shift was presumably due to preferential electrostatic interactions between the cationic DA and the anionic SDS. Indeed, whilst the SDS-modified paper improved the DA current five-fold, the non-ionic Tween-20 and cationic tetradecyltrimethylammonium bromide surfactants had no effect or reduced the current, respectively. Furthermore, only the SDS-modified paper showed the selective shift in oxidation potential for DA. DA determination was carried out using square-wave voltammetry between -0.2 and 0.8 V vs. Ag/AgCl, and this ePAD was able to detect DA over a linear range of 1-100 μM with a detection limit (S/N=3) of 0.37 μM. The ePAD seems suitable as a low cost, easy-to-use, portable device for the selective quantitation of DA in human serum samples.
Collapse
|
12
|
Giordano BC, Burgi DS, Hart SJ, Terray A. On-line sample pre-concentration in microfluidic devices: a review. Anal Chim Acta 2012; 718:11-24. [PMID: 22305893 DOI: 10.1016/j.aca.2011.12.050] [Citation(s) in RCA: 89] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2011] [Revised: 12/01/2011] [Accepted: 12/21/2011] [Indexed: 11/25/2022]
Abstract
On-line sample preconcentration is an essential tool in the development of microfluidic-based separation platforms. In order to become more competitive with traditional separation techniques, the community must continue to develop newer and more novel methods to improve detection limits, remove unwanted sample matrix components that disrupt separation performance, and enrich/purify analytes for other chip-based actions. Our goal in this review is to familiarize the reader with many of the options available for on-chip concentration enhancement with a focus on those manuscripts that, in our assessment, best describe the fundamental principles that govern those enhancements. Sections discussing both electrophoretic and nonelectrophoretic modes of preconcentration are included with a focus on device design and mechanisms of preconcentration. This review is not meant to be a comprehensive collection of every available example, but our hope is that by learning how on-line sample concentration techniques are being applied today, the reader will be inspired to apply these techniques to further enhance their own programs.
Collapse
Affiliation(s)
- Braden C Giordano
- Naval Research Laboratory, Chemistry Division, Washington, DC 20375-5342, United States.
| | | | | | | |
Collapse
|
13
|
|
14
|
Abstract
The use of mixtures of ionic and zwitterionic surfactants in poly(dimethylsiloxane) (PDMS) microchips is reported. The effect of surfactant concentration on electroosmotic flow (EOF) was studied for a single anionic surfactant (sodium dodecyl sulfate, SDS), a single zwitterionic surfactant (N-tetradecylammonium-N,N-dimethyl-3-ammonio-1-propanesulfonate, TDAPS), and a mixed SDS/TDAPS surfactant system. SDS increased the EOF as reported previously while TDAPS showed an initial increase in EOF followed by a reduction at higher concentrations. When TDAPS was added to a solution containing SDS, the EOF decreased in a concentration-dependent manner. The EOF for all three surfactant systems followed expected pH trends, with increasing EOF at higher pH. The mixed surfactant system allowed tuning of the EOF across a range of pH and concentration conditions. After establishing the EOF behavior, the adsorption/desorption kinetics were measured and showed a slower adsorption/desorption rate for TDAPS than SDS. Finally, the separation and electrochemical detection of model catecholamines in buffer and reduced glutathione in red blood cell lysate using the mixed surfactant system were explored. The mixed surfactant system provided shorter analysis times and/or improved resolution when compared to the single surfactant systems.
Collapse
Affiliation(s)
- Qian Guan
- Department of Chemistry, Colorado State University, Fort Collins, CO, USA
| | | | | |
Collapse
|
15
|
Malá Z, Gebauer P, Boček P. Contemporary sample stacking in analytical electrophoresis. Electrophoresis 2010; 32:116-26. [DOI: 10.1002/elps.201000327] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2010] [Revised: 08/09/2010] [Accepted: 08/09/2010] [Indexed: 12/31/2022]
|