1
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Jing M, Gao W, Hutchins P. Development of Two-Dimensional Offline Coupling of Asymmetrical Flow Field-Flow Fractionation and Capillary Electrophoresis for the Separation of a Five-Component Submicrometer Particle Mixture. Anal Chem 2023; 95:3840-3847. [PMID: 36762381 DOI: 10.1021/acs.analchem.2c05352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Submicrometer colloidal particles are widely applied in a variety of industrial products. While precise size and surface charge control is crucial to the stability and functionality of these materials, a tool to determine these properties with sufficient resolution, detection sensitivity, and robustness is still not available. The recently reported offline coupling of asymmetrical flow field-flow fractionation and capillary electrophoresis (AF4 × CE) shows success in improving the separation resolution for nanoparticles; however, challenges remain for sensitive multiple-component submicrometer particle analysis because of wide size and mobility distributions. We here report offline coupling of an AF4 method and a CE method, which utilized the online reversed electrode polarity stacking mode, to successfully characterize a five-component, submicrometer particle mixture. The mixture was successfully separated and detected with an improved inter- and intracomponent resolution. Therefore, our developed platform holds great potential for industrial applications involving multiple-component particle mixtures.
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Affiliation(s)
- Meng Jing
- Analytical Science, Core R&D, Dow, Collegeville, Pennsylvania 19426, United States
| | - Wei Gao
- Analytical Science, Core R&D, Dow, Collegeville, Pennsylvania 19426, United States
| | - Paul Hutchins
- Analytical Science, Core R&D, Dow, Midland, Michigan 48640, United States
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2
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Mukunda DC, Rodrigues J, Joshi VK, Raghushaker CR, Mahato KK. A comprehensive review on LED-induced fluorescence in diagnostic pathology. Biosens Bioelectron 2022; 209:114230. [PMID: 35421670 DOI: 10.1016/j.bios.2022.114230] [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: 09/23/2021] [Revised: 03/19/2022] [Accepted: 03/25/2022] [Indexed: 11/02/2022]
Abstract
Sensitivity, specificity, mobility, and affordability are important criteria to consider for developing diagnostic instruments in common use. Fluorescence spectroscopy has been demonstrating substantial potential in the clinical diagnosis of diseases and evaluating the underlying causes of pathogenesis. A higher degree of device integration with appropriate sensitivity and reasonable cost would further boost the value of the fluorescence techniques in clinical diagnosis and aid in the reduction of healthcare expenses, which is a key economic concern in emerging markets. Light-emitting diodes (LEDs), which are inexpensive and smaller are attractive alternatives to conventional excitation sources in fluorescence spectroscopy, are gaining a lot of momentum in the development of affordable, compact analytical instruments of clinical relevance. The commercial availability of a broad range of LED wavelengths (255-4600 nm) has opened up new avenues for targeting a wide range of clinically significant molecules (both endogenous and exogenous), thereby diagnosing a range of clinical illnesses. As a result, we have specifically examined the uses of LED-induced fluorescence (LED-IF) in preclinical and clinical evaluations of pathological conditions, considering the present advancements in the field.
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Affiliation(s)
| | - Jackson Rodrigues
- Department of Biophysics, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, Karnataka-576104, India
| | - Vijay Kumar Joshi
- Department of Biophysics, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, Karnataka-576104, India
| | - Chandavalli Ramappa Raghushaker
- Department of Biophysics, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, Karnataka-576104, India
| | - Krishna Kishore Mahato
- Department of Biophysics, Manipal School of Life Sciences, Manipal Academy of Higher Education, Manipal, Karnataka-576104, India.
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3
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Yahaya N, Huang ZA, Yan B, Chen DDY. Capillary electrophoresis-mass spectrometry analysis of bisphenol A and its analogues in bottled tea beverages with dynamic pH focusing. Food Chem 2022; 372:131220. [PMID: 34607048 DOI: 10.1016/j.foodchem.2021.131220] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 09/07/2021] [Accepted: 09/23/2021] [Indexed: 01/25/2023]
Abstract
A simple and sensitive method for the determination of bisphenol A and its analogues at the ng/mL level in bottled tea beverages is presented. This method utilized a dynamic pH junction to focus the analyte into a more concentrated zone, based on the electrophoretic mobility difference of analytes in the sample matrix and background electrolytes in capillary electrophoresis coupled to mass spectrometry (CE-MS). The optimised analyte focusing led to enhanced signal detection with average peak heights for five bisphenols of 53-170 folds higher than conventional injections. Under optimised conditions, the method showed good linearity in the range of 0.1-100 ng/mL, excellent limits of detection (0.03-0.04 ng/mL), good analyte recovery (80.3-118.1%) with acceptable relative standard deviations (<12%). The limits of quantifications were below the maximum permissible content of bisphenol A set by the European Commission for this product. This method was used to quantitatively analyse bisphenols in six different kinds of bottled tea beverages, making it a promising tool for practical applications.
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Affiliation(s)
- Noorfatimah Yahaya
- Integrative Medicine Cluster, Advanced Medical and Dental Institute (AMDI), Universiti Sains Malaysia, 13200 Bertam Kepala Batas, Penang, Malaysia; Department of Chemistry, University of British Columbia, Vancouver V6T 1Z1, BC, Canada.
| | - Zi-Ao Huang
- Department of Chemistry, University of British Columbia, Vancouver V6T 1Z1, BC, Canada
| | - Binjun Yan
- Department of Chemistry, University of British Columbia, Vancouver V6T 1Z1, BC, Canada; College of Pharmaceutical Science, Zhejiang Chinese Medical University, Hangzhou 310053, Zhejiang, China
| | - David D Y Chen
- Department of Chemistry, University of British Columbia, Vancouver V6T 1Z1, BC, Canada.
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4
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Xu L, Meng W, Lu J, Cui F, Gao L, Chen L, Xin Y. Hyphenation of field‐amplified sample injection and transient isotachophoresis in CE for the determination of sotalol and metoprolol in human urine samples. J Sep Sci 2020; 43:2193-2200. [DOI: 10.1002/jssc.201901165] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 02/12/2020] [Accepted: 02/13/2020] [Indexed: 11/10/2022]
Affiliation(s)
- Lei Xu
- College of Chemistry and Chemical EngineeringQiqihar University Qiqihar P.R. China
| | - Weiqi Meng
- College of Chemistry and Chemical EngineeringQiqihar University Qiqihar P.R. China
| | - Jing Lu
- College of Chemistry and Chemical EngineeringQiqihar University Qiqihar P.R. China
| | - Fengjuan Cui
- College of Chemistry and Chemical EngineeringQiqihar University Qiqihar P.R. China
| | - Lidi Gao
- College of Chemistry and Chemical EngineeringQiqihar University Qiqihar P.R. China
| | - Lin Chen
- College of Chemistry and Chemical EngineeringQiqihar University Qiqihar P.R. China
| | - Yang Xin
- College of Chemistry and Chemical EngineeringQiqihar University Qiqihar P.R. China
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5
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Open-tubular admicellar electrochromatography of charged analytes. Talanta 2020; 208:120401. [PMID: 31816751 DOI: 10.1016/j.talanta.2019.120401] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 09/26/2019] [Accepted: 09/27/2019] [Indexed: 11/23/2022]
Abstract
Fundamental studies on the separation of cationic and anionic analytes in open-tubular admicellar electrochromatography (OT-AMEC) using cetyltrimethylammonium bromide (CTAB) and fused silica capillaries are presented. OT-AMEC was compared with open-tubular admicellar liquid chromatography (OT-AMLC) by running the two methods using the same mobile phases. The mobile phases were buffered at pH ≥ 6 and contained a low concentration (above the critical surface aggregation concentration and below the critical micelle concentration) of CTAB. The stationary pseudophase of CTAB admicelles were formed at the solid surface and liquid interface inside the capillary by simply conditioning the capillary with the mobile phase. Separations were performed in a 30 cm (21.5 cm to UV detector) long and 50 μm inner diameter capillary, using low pressure (50 mbar) in OT-AMLC and high voltage (15 kV at negative polarity) in OT-AMEC. The appropriate equations for the experimental estimation of retention factor (k) values of analytes were discussed. For anionic analytes, k in OT-AMEC were carefully determined by considering the observed interaction between CTAB monomers and tested analytes. The calculated k for each analyte was found similar in OT-AMLC and OT-AMEC, although the mechanism of retention was not entirely different due to the contribution of electrophoresis in OT-AMEC. Studies on the addition of a typical (i.e., acetonitrile) and atypical modifier (i.e., nonyl-β-glucoside) into the mobile phase, and sample focusing with >10x improvement in peak height under isocratic conditions were also conducted.
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6
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Hou M, Zhang M, Chen L, Gong K, Pan C, Wang Y. Amplification of lysozyme signal detected in capillary electrophoresis using mixed polymer brushes coating with switchable properties. Talanta 2019; 202:426-435. [PMID: 31171204 DOI: 10.1016/j.talanta.2019.05.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 04/22/2019] [Accepted: 05/02/2019] [Indexed: 12/29/2022]
Abstract
In this work, a mixed polymer brushes based on poly(2-methyl-2-oxazoline) (PMOXA) and poly(acrylic acid) (PAA) coated capillary with switchable protein adsorption/desorption properties was developed and applied for on-line extraction and preconcentration of lysozyme. The study of electroosmotic flow (EOF) and fluorescence microscope showed that the inner surface charge of PMOXA/PAA mixed brush coated capillary displayed the switchable behavior toward the change of pH value and ionic strength (I), and PMOXA/PAA mixed brushes coated capillary could adsorb high amounts of lysozyme at pH 7 (I = 10-5 M), and the most of adsorbed lysozyme could then be desorbed at pH 3 (I = 10-1 M). Subsequently, this coated capillary with switchable lysozyme adsorption/desorption ability was applied for on-line extraction and preconcentration of lysozyme during capillary electrophoresis (CE) performance. Under the process of on-line preconcentration, the detection signal (peak area) of lysozyme obtained in PMOXA/PAA coated capillary was 26 times that obtained in bare capillary under normal CE while the contour chain length of PAA was 1.56 times that of PMOXA. Moreover, the value of low detection limit (LOD) of lysozyme using above coated capillary under on-line preconcentration method reached to 4.5 × 10-9 mg/mL, and 1 × 105-fold sensitivity enhancement was realized for lysozyme as compared with the bare capillary under normal CE.
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Affiliation(s)
- Mingxin Hou
- CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, 230026, PR China
| | - Miao Zhang
- CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, 230026, PR China
| | - Lijuan Chen
- CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, 230026, PR China; Colllege of Materials and Chemical Engineering, West Anhui University, Luan, 237012, PR China
| | - Kai Gong
- CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, 230026, PR China
| | - Chao Pan
- CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, 230026, PR China
| | - Yanmei Wang
- CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, 230026, PR China.
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7
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Yan P, Zhang K, Wang L, Tong W, Chen DDY. Quantitative analysis of microcystin variants by capillary electrophoresis mass spectrometry with dynamic pH barrage junction focusing. Electrophoresis 2019; 40:2285-2293. [PMID: 30924152 DOI: 10.1002/elps.201900042] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 03/04/2019] [Accepted: 03/24/2019] [Indexed: 01/08/2023]
Abstract
Dynamic pH junction is an online focusing method in CE based on the electrophoretic mobility difference of analytes in the sample matrix and the background electrolyte. An advantage of this method over the conventional CE is that the sensitivity can be significantly improved. By injecting a long sample plug in the capillary and focusing the analytes at the pH boundary between the background electrolyte and sample matrix, the LOD can be improved by 10-100 folds. The dynamic pH junction method can be easily coupled with ESI-MS. In this work, we used this method for the analysis of microcystins (MCs). The detection limits and dynamic ranges were studied. The separation was optimized by adjusting the injection time, and concentrations and pH values of the background electrolyte. The optimization of analyte focusing leads to enhanced detection response compared to conventional injections, achieving 200-400 fold higher averaged peak heights for four microcystin (MC) variants. More importantly, this method was successfully used for the quantitative analysis of microcystins (MCs) in crude algae samples from natural water bodies, making it promising for practical applications.
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Affiliation(s)
- Ping Yan
- Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, Jiangsu Key Laboratory of Biomedical Materials, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing, P. R. China
| | - Keke Zhang
- Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, Jiangsu Key Laboratory of Biomedical Materials, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing, P. R. China
| | - Lingyu Wang
- Department of Chemistry, University of British Columbia, Vancouver, BC, Canada
| | - Wenjun Tong
- Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, Jiangsu Key Laboratory of Biomedical Materials, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing, P. R. China
| | - David D Y Chen
- Department of Chemistry, University of British Columbia, Vancouver, BC, Canada
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8
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Wang J, Wang C, Fan L, Zhao L, Tan WS. Simultaneous detection of nicotinamide adenine nucleotides and adenylate pool to quantify redox and energy states in mAb-producing CHO cells by capillary electrophoresis. Anal Bioanal Chem 2019; 411:2971-2979. [PMID: 30923861 DOI: 10.1007/s00216-019-01747-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2018] [Revised: 02/15/2019] [Accepted: 03/01/2019] [Indexed: 11/24/2022]
Abstract
Chinese hamster ovary (CHO) cells are predominant in the production of therapeutic proteins to treat various diseases. Characterization and investigation of CHO cell metabolism in a quick and simple way could boost process and cell line development. Therefore, a method to simultaneously detect seven redox- and energy-related metabolites in CHO cells by capillary electrophoresis has been developed. An on-line focusing technique was applied to improve the peak shape and resolution by using a 50 μm × 44 cm uncoated fused silica capillary. Key parameters and their interactions were investigated by design of experiments (DoE) and optimized conditions were determined by desirability function as follows: 24 °C, 95 mM, and pH 9.4 of BGE. The method was validated to ensure sensitivity, linearity, and reproducibility. The limits of detection (LODs) ranged from 0.050 to 0.688 mg/L for seven metabolites, and correlation coefficients of linearity were all greater than 0.996. The relative standard deviations (RSD) of migration time and peak area were smaller than 0.872% and 5.5%, respectively, except for NADPH, and the recoveries were between 97.5 and 101.2%. The method was successfully applied to analyze the extracts from CHO cells under two different culture conditions. Graphical abstract.
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Affiliation(s)
- Jiaqi Wang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Box 309, 130 Meilong Road, Shanghai, 200237, China
| | - Chen Wang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Box 309, 130 Meilong Road, Shanghai, 200237, China
| | - Li Fan
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Box 309, 130 Meilong Road, Shanghai, 200237, China.,Shanghai BioEngine Sci-Tech Co. Ltd, Shanghai, 201203, China
| | - Liang Zhao
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Box 309, 130 Meilong Road, Shanghai, 200237, China.
| | - Wen-Song Tan
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Box 309, 130 Meilong Road, Shanghai, 200237, China
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9
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Ghiasvand A, Feng Z, Quirino JP. Enrichment and Separation of Cationic, Neutral, and Chiral Analytes by Micelle to Cyclodextrin Stacking–Micellar Electrokinetic Chromatography. Anal Chem 2018; 91:1752-1757. [DOI: 10.1021/acs.analchem.8b03542] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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10
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Rageh AH, Pyell U. “Pseudostationary Ion-Exchanger” Sweeping as an Online Enrichment Technique in the Determination of Nucleosides in Urine via Micellar Electrokinetic Chromatography. Chromatographia 2018. [DOI: 10.1007/s10337-018-3570-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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11
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Song YZ, Zhang XX, Liu JJ, Fang F, Wu ZY. Electrokinetic stacking of electrically neutral analytes with paper-based analytical device. Talanta 2018; 182:247-252. [DOI: 10.1016/j.talanta.2018.01.090] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 01/15/2018] [Accepted: 01/30/2018] [Indexed: 11/26/2022]
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12
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Liu L, Wan Q, Xu X, Duan S, Yang C. Combination of micelle collapse and field-amplified sample stacking in capillary electrophoresis for determination of trimethoprim and sulfamethoxazole in animal-originated foodstuffs. Food Chem 2017; 219:7-12. [DOI: 10.1016/j.foodchem.2016.09.118] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Revised: 09/02/2016] [Accepted: 09/18/2016] [Indexed: 11/25/2022]
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13
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The Concept of Stationary and Moving Boundaries Modelled as Accelerating or Decelerating Planes in the Understanding of Sweeping Processes Employed for Online Focusing in Capillary Zone Electrophoresis and Electrokinetic Chromatography. Chromatographia 2017. [DOI: 10.1007/s10337-017-3261-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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14
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Zhang Z, Zhu G, Peuchen EH, Dovichi NJ. Preparation of linear polyacrylamide coating and strong cationic exchange hybrid monolith in a single capillary, and its application as an automated platform for bottom-up proteomics by capillary electrophoresis-mass spectrometry. Mikrochim Acta 2017. [DOI: 10.1007/s00604-017-2084-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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15
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Zhang Y, Chen W, Zhang Y, Zhang Y, Zhu L, He P, Wang Q. Sensitive analysis of reduced glutathione in bacteria and HaCaT cells by capillary electrophoresis via online pre-concentration of transient trapping combined with the dynamic pH junction mode. NEW J CHEM 2017. [DOI: 10.1039/c7nj02184d] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new method of capillary electrophoresis was developed for the sensitive determination of glutathione in biological samples.
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Affiliation(s)
- Yan Zhang
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai 200241
- P. R. China
| | - Wujuan Chen
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai 200241
- P. R. China
| | - Yi Zhang
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai 200241
- P. R. China
| | - Yating Zhang
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai 200241
- P. R. China
| | - Luqi Zhu
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai 200241
- P. R. China
| | - Pingang He
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai 200241
- P. R. China
| | - Qingjiang Wang
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai 200241
- P. R. China
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16
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Analysis of four antimigraine drugs in two ternary mixtures by sweeping-micellar electrokinetic chromatography with retention factor gradient effect and dynamic pH junction. Microchem J 2016. [DOI: 10.1016/j.microc.2016.01.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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17
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Hussain S, Malik AH, Iyer PK. FRET-assisted selective detection of flavins via cationic conjugated polyelectrolyte under physiological conditions. J Mater Chem B 2016; 4:4439-4446. [DOI: 10.1039/c6tb01350c] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Cationic conjugated polyelectrolyte PMI performs ppb level detection and discrimination of flavins (RF, FMN and FAD) in aqueous media as well as in biological medium like serum.
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Affiliation(s)
- Sameer Hussain
- Department of Chemistry
- Indian Institute of Technology Guwahati
- Guwahati-781039
- India
| | - Akhtar Hussain Malik
- Department of Chemistry
- Indian Institute of Technology Guwahati
- Guwahati-781039
- India
| | - Parameswar Krishnan Iyer
- Department of Chemistry
- Indian Institute of Technology Guwahati
- Guwahati-781039
- India
- Centre for Nanotechnology
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18
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Cheng HL, Tsai YH, Hsu WL, Lin YH. An on-line stacking capillary electrophoresis method for the analysis of Δ9-tetrahydrocannabinol and its metabolites. J Chromatogr A 2015; 1426:226-32. [DOI: 10.1016/j.chroma.2015.11.032] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 10/31/2015] [Accepted: 11/09/2015] [Indexed: 11/25/2022]
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19
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Xu X, Jia Z, Shu Y, Liu L. Dynamic pH junction–sweeping technique for on-line concentration of acidic amino acids in human serum by capillary electrophoresis with indirect UV detection. J Chromatogr B Analyt Technol Biomed Life Sci 2015; 980:20-7. [DOI: 10.1016/j.jchromb.2014.12.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Revised: 12/06/2014] [Accepted: 12/11/2014] [Indexed: 11/29/2022]
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20
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Tubaon RM, Haddad PR, Quirino JP. High-sensitivity analysis of anionic sulfonamides by capillary electrophoresis using a synergistic stacking approach. J Chromatogr A 2014; 1349:129-34. [PMID: 24856966 DOI: 10.1016/j.chroma.2014.05.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Revised: 03/19/2014] [Accepted: 05/02/2014] [Indexed: 11/19/2022]
Abstract
A synergistic stacking approach whereby field-enhanced sample injection and micelle-to-solvent stacking in capillary zone electrophoresis are combined has been developed and has been applied to the separation and quantification of anionic sulfonamides. Electrokinetic injection of the sample in a low conductivity alkaline diluent was performed for 90s at -15kV. Micelle-to-solvent stacking was then undertaken by hydrodynamic injection of micellar cetyltrimethylammonium bromide solution prior to the electrokinetic injection of sample that also contained 50% methanol. This combined stacking approach, when compared to a typical hydrostatic injection, provided improvements in peak height and corrected peak area in the range of 397-1024 and 758-1246, respectively. Limits of quantification in the range of 0.01-0.03μg/mL were obtained for sulfamerazine, sulfamethazine and sulfamethizole and were sufficient for the determination of these analytes in river water. The percentage recovery and accuracy values obtained for a fortified river water sample that had been subjected to sample preparation by evaporation and reconstitution with diluent were 74-135%. Intra-day and inter-day repeatabilities for migration time, peak height, and corrected peak area were in the range 0.5-5.0% (percentage relative standard deviation, n=8) and these relatively low values were attributed to the use of a stable capillary coating established by the successive multiple ionic-polymer layer technique.
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Affiliation(s)
- Ria Marni Tubaon
- Australian Centre for Research on Separation Science, School of Physical Sciences-Chemistry, University of Tasmania, Hobart, Tasmania 7001, Australia
| | - Paul R Haddad
- Australian Centre for Research on Separation Science, School of Physical Sciences-Chemistry, University of Tasmania, Hobart, Tasmania 7001, Australia
| | - Joselito P Quirino
- Australian Centre for Research on Separation Science, School of Physical Sciences-Chemistry, University of Tasmania, Hobart, Tasmania 7001, Australia.
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21
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Novel and simple headspace in-tube microextraction coupled with capillary electrophoresis. J Chromatogr A 2014; 1346:117-22. [PMID: 24811149 DOI: 10.1016/j.chroma.2014.04.052] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Revised: 04/16/2014] [Accepted: 04/17/2014] [Indexed: 11/21/2022]
Abstract
In liquid phase microextraction, high enrichment factors can be obtained using an acceptor phase of small volume. By hanging an acceptor drop at the separation capillary tip, single drop microextraction (SDME) can be in-line coupled with capillary electrophoresis (CE). The small surface-to-volume ratio of the drop enables high enrichment factors to be obtained in a short time. One practical issue in SDME is how to keep the drop attached to the capillary stable. Here, we present novel but extremely simple in-tube microextraction (ITME) using the liquid inside the capillary as an acceptor phase, without forming a drop at the capillary tip. As a first example, ITME has been combined with headspace (HS) extraction. Simply by placing a capillary filled with a basic run buffer in the HS above an acidic donor solution, volatile acidic analytes were extracted into the acceptor phase in the capillary. After extraction, electrophoresis of the extracts in the capillary was carried out. Owing to the robust nature of the acceptor phase, the extraction temperature and time ranges of HS-ITME can be extended significantly, compared to HS-SDME. The enrichment factors for chlorophenols in a standard solution were up to 1100 under an optimal HS-ITME condition of 80°C for 15min and the limits of detections (LODs) obtained by monitoring the absorbance at 214nm were about 4nM. The whole procedures of HS-ITME-CE were carried out automatically using built-in programs of a commercial CE instrument.
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22
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Kukusamude C, Srijaranai S, Quirino JP. Anionic microemulsion to solvent stacking for on-line sample concentration of cationic analytes in capillary electrophoresis. Electrophoresis 2014; 35:1478-83. [DOI: 10.1002/elps.201300512] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2013] [Revised: 02/02/2014] [Accepted: 02/03/2014] [Indexed: 11/09/2022]
Affiliation(s)
- Chunyapuk Kukusamude
- Australian Centre for Research on Separation Science (ACROSS); School of Physical Sciences-Chemistry; University of Tasmania; Hobart Australia
- Materials Chemistry Research Unit; Department of Chemistry and Center of Excellence for Innovation in Chemistry; Faculty of Science; Khon Kaen University; Khon Kaen Thailand
| | - Supalax Srijaranai
- Materials Chemistry Research Unit; Department of Chemistry and Center of Excellence for Innovation in Chemistry; Faculty of Science; Khon Kaen University; Khon Kaen Thailand
| | - Joselito P. Quirino
- Australian Centre for Research on Separation Science (ACROSS); School of Physical Sciences-Chemistry; University of Tasmania; Hobart Australia
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23
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Kong Y, Yuan J, Wang Z, Hou Z, Yu J, Jin H, Xie M, Chang N, Xu W, Zhao Y, Tang Y. Assay of melamine in milk products with a pH-mediated stacking technique in capillary electrophoresis. J Sep Sci 2014; 37:717-24. [DOI: 10.1002/jssc.201300603] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Revised: 12/10/2013] [Accepted: 12/20/2013] [Indexed: 11/11/2022]
Affiliation(s)
- Yu Kong
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education; School of Life Science and Technology; Xi'an Jiaotong University; Xi'an P.R. China
| | - Jiaqiang Yuan
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education; School of Life Science and Technology; Xi'an Jiaotong University; Xi'an P.R. China
| | - Zilong Wang
- Institute of Analytical Science; School of Science; Xi'an Jiaotong University; Xi'an P.R. China
| | - Zhanwu Hou
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education; School of Life Science and Technology; Xi'an Jiaotong University; Xi'an P.R. China
| | - Jiang Yu
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education; School of Life Science and Technology; Xi'an Jiaotong University; Xi'an P.R. China
| | - Han Jin
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education; School of Life Science and Technology; Xi'an Jiaotong University; Xi'an P.R. China
| | - Meihua Xie
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education; School of Life Science and Technology; Xi'an Jiaotong University; Xi'an P.R. China
| | - Nan Chang
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education; School of Life Science and Technology; Xi'an Jiaotong University; Xi'an P.R. China
| | - Weiyong Xu
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education; School of Life Science and Technology; Xi'an Jiaotong University; Xi'an P.R. China
| | - Yongxi Zhao
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education; School of Life Science and Technology; Xi'an Jiaotong University; Xi'an P.R. China
| | - Yuhai Tang
- Institute of Analytical Science; School of Science; Xi'an Jiaotong University; Xi'an P.R. China
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24
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El-Awady M, Pyell U. Processes involved in sweeping as sample enrichment method in cyclodextrin-modified micellar electrokinetic chromatography of hydrophobic basic analytes. Electrophoresis 2014; 35:605-16. [DOI: 10.1002/elps.201300259] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2013] [Revised: 12/02/2013] [Accepted: 12/02/2013] [Indexed: 11/08/2022]
Affiliation(s)
- Mohamed El-Awady
- Department of Chemistry; University of Marburg; Marburg Germany
- Faculty of Pharmacy; Department of Analytical Chemistry; Mansoura University; Mansoura Egypt
| | - Ute Pyell
- Department of Chemistry; University of Marburg; Marburg Germany
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25
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Yang X, Zhang S, Wang J, Wang C, Wang Z. On-line two-step stacking in capillary zone electrophoresis for the preconcentration of strychnine and brucine. Anal Chim Acta 2014; 814:63-8. [PMID: 24528845 DOI: 10.1016/j.aca.2014.01.027] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2013] [Revised: 01/07/2014] [Accepted: 01/10/2014] [Indexed: 10/25/2022]
Abstract
An on-line sample preconcentration method by two-step stacking i.e., sweeping and micelle to solvent stacking, in capillary zone electrophoresis (CZE) has been developed for the determination of strychnine and brucine in traditional Chinese herbal medicines. After experimental optimizations, the best separation was achieved by using 75 mM phosphate buffer (pH 2.5) with 30% methanol (v/v). Compared with normal CZE injection, 51- and 38-fold improvement in concentration sensitivity was achieved for strychnine and brucine, respectively. The calibration curve was linear in the range of 0.1-5.0 μg mL(-1) for both strychnine and brucine, with the correlation coefficients of 0.9998 and 0.9997, respectively. The limits of detection (S/N=3) for both alkaloids were 0.01 μg mL(-1). The inter-day (n=8) and intra-day (n=5) reproducibilities expressed as the relative standard deviations for corrected peak area were less than 9.5%. The method was applied to determine strychnine and brucine in two Chinese herbal medicines, with recoveries ranging from 94.2% to 105.4%. The results indicated that the method is simple, rapid, reliable, and can be applied to determine strychnos alkaloids in traditional Chinese herbal medicines.
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Affiliation(s)
- Xiumin Yang
- Department of chemistry, College of Science, Agricultural University of Hebei, Baoding 071001, PR China
| | - Shuaihua Zhang
- Department of chemistry, College of Science, Agricultural University of Hebei, Baoding 071001, PR China
| | - Juntao Wang
- Department of chemistry, College of Science, Agricultural University of Hebei, Baoding 071001, PR China
| | - Chun Wang
- Department of chemistry, College of Science, Agricultural University of Hebei, Baoding 071001, PR China
| | - Zhi Wang
- Department of chemistry, College of Science, Agricultural University of Hebei, Baoding 071001, PR China.
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26
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Online dynamic pH junction–sweeping for the determination of benzoic and sorbic acids in food products by capillary electrophoresis. Anal Bioanal Chem 2013; 406:635-41. [DOI: 10.1007/s00216-013-7481-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Revised: 10/29/2013] [Accepted: 11/01/2013] [Indexed: 12/19/2022]
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27
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El-Awady M, Belal F, Pyell U. Robust analysis of the hydrophobic basic analytes loratadine and desloratadine in pharmaceutical preparations and biological fluids by sweeping—cyclodextrin-modified micellar electrokinetic chromatography. J Chromatogr A 2013; 1309:64-75. [DOI: 10.1016/j.chroma.2013.08.020] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Revised: 08/02/2013] [Accepted: 08/06/2013] [Indexed: 10/26/2022]
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28
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El-Awady M, Pyell U. Sweeping as a multistep enrichment process in micellar electrokinetic chromatography: The retention factor gradient effect. J Chromatogr A 2013; 1297:213-25. [DOI: 10.1016/j.chroma.2013.04.069] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Revised: 04/18/2013] [Accepted: 04/21/2013] [Indexed: 10/26/2022]
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29
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Tang W, Ge S, Gao F, Wang G, Wang Q, He P, Fang Y. On-line sample preconcentration technique based on a dynamic pH junction in CE-amperometric detection for the analysis of biogenic amines in urine. Electrophoresis 2013; 34:2041-8. [DOI: 10.1002/elps.201300116] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Revised: 04/04/2013] [Accepted: 04/07/2013] [Indexed: 11/12/2022]
Affiliation(s)
- Wanrong Tang
- Department of Chemistry; East China Normal University; Shanghai; P. R. China
| | - Shuli Ge
- Department of Chemistry; East China Normal University; Shanghai; P. R. China
| | - Fan Gao
- Department of Chemistry; East China Normal University; Shanghai; P. R. China
| | - Guan Wang
- Department of Chemistry; East China Normal University; Shanghai; P. R. China
| | - Qingjiang Wang
- Department of Chemistry; East China Normal University; Shanghai; P. R. China
| | - Pingang He
- Department of Chemistry; East China Normal University; Shanghai; P. R. China
| | - Yuzhi Fang
- Department of Chemistry; East China Normal University; Shanghai; P. R. China
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30
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Chen J, Sun J, Liu S. Determination of Riboflavin in Cereal Grains by Capillary Electrophoresis with Laser-Induced Fluorescence Detection with On-Line Concentration. ANAL LETT 2013. [DOI: 10.1080/00032719.2012.747097] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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31
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de Kort BJ, de Jong GJ, Somsen GW. Native fluorescence detection of biomolecular and pharmaceutical compounds in capillary electrophoresis: Detector designs, performance and applications: A review. Anal Chim Acta 2013; 766:13-33. [DOI: 10.1016/j.aca.2012.12.006] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2012] [Revised: 12/01/2012] [Accepted: 12/03/2012] [Indexed: 01/05/2023]
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32
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Hsieh BC, Chen RLC, Tsai T. Quantification of 5-aminolevulinic acid by CE using dynamic pH junction technique. J Sep Sci 2013; 36:803-8. [DOI: 10.1002/jssc.201200889] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2012] [Revised: 11/02/2012] [Accepted: 11/04/2012] [Indexed: 11/10/2022]
Affiliation(s)
- Bo-Chuan Hsieh
- Graduate Institute of Biomedical Materials and Tissue Engineering, College of Oral Medicine; Taipei Medical University; Taipei Taiwan
| | - Richie L. C. Chen
- Department of Bio-Industrial Mechatronics Engineering; National Taiwan University; Taipei Taiwan
| | - Tsuimin Tsai
- Graduate Institute of Biomedical Materials and Tissue Engineering, College of Oral Medicine; Taipei Medical University; Taipei Taiwan
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33
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Kubalczyk P, Bald E. Methods of Analyte Concentration in a Capillary. SPRINGER SERIES IN CHEMICAL PHYSICS 2013. [DOI: 10.1007/978-3-642-35043-6_12] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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34
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Rabanes HR, Aranas AT, Benbow NL, Quirino JP. Synergistic effect of field enhanced sample injection on micelle to solvent stacking in capillary electrophoresis. J Chromatogr A 2012; 1267:74-9. [DOI: 10.1016/j.chroma.2012.08.073] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2012] [Revised: 08/22/2012] [Accepted: 08/24/2012] [Indexed: 12/28/2022]
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35
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Dong YL, Zhang HG, Rahman ZU, Zhang HJ, Chen XJ, Hu J, Chen XG. A new on-line concentration method of cationic molecules in capillary electrophoresis by a hyphenated micelle to solvent stacking coupling with large amount sample electrokinetic stacking injection. J Chromatogr A 2012; 1265:176-80. [DOI: 10.1016/j.chroma.2012.09.082] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2012] [Revised: 09/17/2012] [Accepted: 09/18/2012] [Indexed: 11/16/2022]
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36
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Processes involved in sweeping under inhomogeneous electric field conditions as sample enrichment procedure in micellar electrokinetic chromatography. J Chromatogr A 2012; 1264:124-36. [DOI: 10.1016/j.chroma.2012.09.044] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2012] [Revised: 09/13/2012] [Accepted: 09/18/2012] [Indexed: 11/19/2022]
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37
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Zhang S, Ma R, Yang X, Wang C, Wang Z. On-line sample concentration and determination of cationic alkaloids in human plasma by micelle to solvent stacking in capillary zone electrophoresis. J Chromatogr B Analyt Technol Biomed Life Sci 2012; 906:41-7. [DOI: 10.1016/j.jchromb.2012.08.017] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Revised: 07/30/2012] [Accepted: 08/13/2012] [Indexed: 10/28/2022]
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38
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Improvement of the sensitivity of 2D LC-MEKC separation of phenolic acids and flavonoids natural antioxidants using the on-line preconcentration step. Electrophoresis 2012; 33:2464-73. [DOI: 10.1002/elps.201100594] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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39
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Quirino JP, Aranas AT. On-line sample concentration via micelle to solvent stacking of cations prepared with aqueous organic solvents in capillary electrophoresis. Electrophoresis 2012; 33:2167-75. [DOI: 10.1002/elps.201200023] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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40
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Quirino JP, Aranas AT. Simultaneous electrokinetic and hydrodynamic injection with on-line sample concentration via micelle to solvent stacking in micellar electrokinetic chromatography. Anal Chim Acta 2012; 733:84-9. [DOI: 10.1016/j.aca.2012.04.032] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2012] [Revised: 04/13/2012] [Accepted: 04/24/2012] [Indexed: 01/25/2023]
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41
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Online sample pre-concentration via dynamic pH junction in capillary and microchip electrophoresis. J Sep Sci 2011; 34:2800-21. [DOI: 10.1002/jssc.201100414] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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42
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Determination of some sulfonylurea herbicides in soil by a novel liquid-phase microextraction combined with sweeping micellar electrokinetic chromatography. Anal Bioanal Chem 2011; 401:1071-81. [DOI: 10.1007/s00216-011-5138-5] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2011] [Revised: 05/17/2011] [Accepted: 05/23/2011] [Indexed: 10/18/2022]
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43
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Cao C, Zhang W, Fan L, Shao J, Li S. Comparative study on sample stacking by moving reaction boundary formed with weak acid and weak or strong alkali in capillary electrophoresis. Talanta 2011; 84:651-8. [DOI: 10.1016/j.talanta.2011.01.059] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2010] [Revised: 01/14/2011] [Accepted: 01/21/2011] [Indexed: 10/18/2022]
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44
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Sueyoshi K, Hashiba K, Kawai T, Kitagawa F, Otsuka K. Hydrophobic labeling of amino acids: Transient trapping-capillary/microchip electrophoresis. Electrophoresis 2011; 32:1233-40. [DOI: 10.1002/elps.201000567] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2010] [Revised: 01/04/2011] [Accepted: 01/04/2011] [Indexed: 11/11/2022]
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45
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Zhu HD, Ren CL, Hu SQ, Zhou XM, Chen HL, Chen XG. Thousand fold concentration of an alkaloid in capillary zone electrophoresis by micelle to solvent stacking. J Chromatogr A 2011; 1218:733-8. [DOI: 10.1016/j.chroma.2010.11.060] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2010] [Revised: 11/19/2010] [Accepted: 11/24/2010] [Indexed: 10/18/2022]
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46
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Quirino JP, Guidote AM. Two-step stacking in capillary zone electrophoresis featuring sweeping and micelle to solvent stacking: II. Organic anions. J Chromatogr A 2011; 1218:1004-10. [DOI: 10.1016/j.chroma.2010.12.095] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2010] [Revised: 12/19/2010] [Accepted: 12/21/2010] [Indexed: 11/28/2022]
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47
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Zhang Z, Du X, Li X. Sweeping with Electrokinetic Injection and Analyte Focusing by Micelle Collapse in Two-Dimensional Separation via Integration of Micellar Electrokinetic Chromatography with Capillary Zone Electrophoresis. Anal Chem 2011; 83:1291-9. [DOI: 10.1021/ac102344y] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Zhaoxiang Zhang
- State Key Laboratory Base of Eco-chemical Engineering, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, P.R. China
| | - Xiuzhen Du
- State Key Laboratory Base of Eco-chemical Engineering, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, P.R. China
| | - Xuemei Li
- State Key Laboratory Base of Eco-chemical Engineering, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, P.R. China
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48
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Chen Y, Zhang L, Cai Z, Chen G. Dynamic pH junction–sweeping for on-line focusing of dipeptides in capillary electrophoresis with laser-induced fluorescence detection. Analyst 2011; 136:1852-8. [DOI: 10.1039/c0an00744g] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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49
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Szökő É, Tábi T. Analysis of biological samples by capillary electrophoresis with laser induced fluorescence detection. J Pharm Biomed Anal 2010; 53:1180-92. [DOI: 10.1016/j.jpba.2010.07.045] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2010] [Revised: 07/23/2010] [Accepted: 07/27/2010] [Indexed: 12/26/2022]
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50
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Quirino JP. Two-step stacking in capillary zone electrophoresis featuring sweeping and micelle to solvent stacking: I. Organic cations. J Chromatogr A 2010; 1217:7776-80. [DOI: 10.1016/j.chroma.2010.10.020] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2010] [Revised: 09/30/2010] [Accepted: 10/05/2010] [Indexed: 11/15/2022]
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