1
|
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.
Collapse
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
| |
Collapse
|
2
|
AL-Othman ZA, Ali I. NANO CAPILLARY ELECTROPHORESIS IN MICROCHIPS: A NEED OF THE PRESENT CENTURY. J LIQ CHROMATOGR R T 2011. [DOI: 10.1080/10826076.2011.566031] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Zeid A. AL-Othman
- a Department of Chemistry, College of Science , King Saud University , Riyadh, Kingdom of Saudi Arabia
| | - Imran Ali
- b Department of Chemistry , Jamia Millia Islamia, (Central University) , New Delhi, India
| |
Collapse
|
3
|
Kubáň P, Seiman A, Kaljurand M. Improving precision of manual hydrodynamic injection in capillary electrophoresis with contactless conductivity detection. J Chromatogr A 2011; 1218:1273-80. [DOI: 10.1016/j.chroma.2010.12.107] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2010] [Revised: 12/20/2010] [Accepted: 12/24/2010] [Indexed: 11/16/2022]
|
4
|
Mark JJP, Kumar A, Demattio H, Hoffmann W, Malik A, Matysik FM. Combination of Headspace Single-Drop Microextraction, Microchip Electrophoresis and Contactless Conductivity Detection for the Determination of Aliphatic Amines in the Biodegradation Process of Seafood Samples. ELECTROANAL 2010. [DOI: 10.1002/elan.201000445] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
5
|
Portable, lightweight, low power, ion chromatographic system with open tubular capillary columns. J Chromatogr A 2010; 1217:5116-23. [DOI: 10.1016/j.chroma.2010.06.017] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2010] [Revised: 05/28/2010] [Accepted: 06/04/2010] [Indexed: 11/22/2022]
|
6
|
Kubán P, Hauser PC. Fundamentals of electrochemical detection techniques for CE and MCE. Electrophoresis 2010; 30:3305-14. [PMID: 19802845 DOI: 10.1002/elps.200900217] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The electroanalytical techniques of amperometry, conductometry and potentiometry match well with the instrumental simplicity of CE. Indeed, all three detection approaches have been reported for electrophoretic separations. However, the characteristics of the three methods are quite distinct and these are not related to the optical methods more commonly employed. A detailed discussion of the underlying principles of each is given. The issue of possible effects of the separation voltage on the electrochemical detection techniques is considered in depth, and approaches to the elimination of such interferences are also discussed for each case.
Collapse
Affiliation(s)
- Pavel Kubán
- Institute of Analytical Chemistry, Academy of Sciences of the Czech Republic, Brno, Czech Republic
| | | |
Collapse
|
7
|
Separation of fluoroquinolones in acidic buffer by capillary electrophoresis with contactless conductivity detection. J Chromatogr A 2009; 1216:5327-32. [DOI: 10.1016/j.chroma.2009.05.014] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2009] [Revised: 05/06/2009] [Accepted: 05/08/2009] [Indexed: 11/17/2022]
|
8
|
TIAN J, QIN W. Quick and Sensitive Determination of Flavonoids by Capillary Electrophoresis-Potential Gradient Detection. ANAL SCI 2009; 25:1119-23. [DOI: 10.2116/analsci.25.1119] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Jing TIAN
- College of Chemistry, Beijing Normal University
| | - Weidong QIN
- College of Chemistry, Beijing Normal University
| |
Collapse
|
9
|
Noblitt SD, Henry CS. Improving the Compatibility of Contact Conductivity Detection with Microchip Electrophoresis Using a Bubble Cell. Anal Chem 2008; 80:7624-30. [DOI: 10.1021/ac8013862] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Scott D. Noblitt
- Department of Chemistry, Colorado State University, 1872 Campus Delivery, Fort Collins, Colorado 80523
| | - Charles S. Henry
- Department of Chemistry, Colorado State University, 1872 Campus Delivery, Fort Collins, Colorado 80523
| |
Collapse
|
10
|
Wu ZY, Fang F, Josserand J, Girault HH. On-column conductivity detection in capillary-chip electrophoresis. Electrophoresis 2008; 28:4612-9. [PMID: 18008311 DOI: 10.1002/elps.200700456] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
On-column conductivity detection in capillary-chip electrophoresis was achieved by actively coupling the high electric field with two sensing electrodes connected to the main capillary channel through two side detection channels. The principle of this concept was demonstrated by using a glass chip with a separation channel incorporating two double-Ts. One double-T was used for sample introduction, and the other for detection. The two electrophoresis electrodes apply the high voltage and provide the current, and the two sensing electrodes connected to the separation channel through the second double-T and probe a potential difference. This potential difference is directly related to the local resistance or the conductivity of the solution defined by the two side channels on the main separation channel. A detection limit of 15 microM (600 ppb or 900 fg) was achieved for potassium ion in a 2 mM Tris-HCl buffer (pH 8.7) with a linear range of 2 orders of magnitude without any stacking. The proposed detection method avoids integrating the sensing electrodes directly within the separation channel and prevents any direct contact of the electrodes with the sample. The baseline signal can also be used for online monitoring of the electric field strength and electroosmosis mobility characterization in the separation channel.
Collapse
Affiliation(s)
- Zhi-Yong Wu
- Research Center of Analytical Science, Northeastern University, Shenyang, PR China.
| | | | | | | |
Collapse
|
11
|
Tay ETT, Law WS, Sim SPC, Feng H, Zhao JH, Li SFY. Floating resistivity detector for microchip electrophoresis. Electrophoresis 2007; 28:4620-8. [DOI: 10.1002/elps.200700185] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
12
|
Timerbaev AR. Recent trends in CE of inorganic ions: From individual to multiple elemental species analysis. Electrophoresis 2007; 28:3420-35. [PMID: 17768723 DOI: 10.1002/elps.200600491] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The major methodological developments in CE related to inorganic analysis are overviewed. This is an update to a previous review article by the author (Timerbaev, A. R., Electrophoresis 2004, 25, 4008-4031) and it covers the review work and innovative research papers published between January 2004 and the first part of 2006. As was underlined in that review, a growing interest of analytical community in providing elemental speciation information found a sound response of the CE method developers. Presently, almost every second research paper in the field of interest deals with element species analysis, the use of inductively coupled plasma MS detection and biochemical applications being the topics of utmost research efforts. On the other hand, advances in general methodology traditionally centered on a CE system modernization for improvements in sensitivity and separation selectivity have attracted less attention over the review period. While there is no indication that inorganic ion applications would surpass by the developmental rate the more matured analysis of organic analytes, CE can now be seen as an analytical technique to be before long customary in a number of inorganic analysis arenas.
Collapse
Affiliation(s)
- Andrei R Timerbaev
- Vernadsky Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, Moscow, Russia.
| |
Collapse
|
13
|
Kubáň P, Nguyen H, Macka M, Haddad P, Hauser P. New Fully Portable Instrument for the Versatile Determination of Cations and Anions by Capillary Electrophoresis with Contactless Conductivity Detection. ELECTROANAL 2007. [DOI: 10.1002/elan.200703908] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
14
|
Yuan L, Wei H, Feng H, Li SFY. Rapid analysis of native neomycin components on a portable capillary electrophoresis system with potential gradient detection. Anal Bioanal Chem 2006; 385:1575-9. [PMID: 16896633 DOI: 10.1007/s00216-006-0617-9] [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: 12/16/2005] [Revised: 04/30/2006] [Accepted: 06/09/2006] [Indexed: 11/25/2022]
Abstract
A simple method based on capillary electrophoresis with potential gradient detection was developed to separate and detect neomycin components within 4 min without a derivatization step. Satisfactory separation and good repeatability were obtained using a separation buffer composed of 1 mM ammonium citrate (pH 3.5). The linearity of the method ranged from 10 to 1000 ppm with a limit of detection for neomycin B of about 7 ppm. After a simple dilution and filtering pretreatment step, neomycin components in three real samples were successfully analyzed without any major interference. Due to its simplicity and reliability, this method could provide an excellent alternative to the assays currently listed in U.S. and European Pharmacopoeia. The experiments were performed on a portable capillary electrophoresis system and, hence, the method can be readily applied to field analysis and point-of-care testing. Figure Photo of portable CE-P2-PGD system.
Collapse
Affiliation(s)
- Lingling Yuan
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore, 117543, Republic of Singapore
| | | | | | | |
Collapse
|
15
|
Xu Y, Qin W, Li SFY. Portable capillary electrophoresis system with potential gradient detection for separation of DNA fragments. Electrophoresis 2005; 26:517-23. [PMID: 15690452 DOI: 10.1002/elps.200410293] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A portable capillary electrophoresis (CE) system with a novel potential gradient detection (PGD) was utilized to separate DNA fragments. For the first time it was demonstrated that separation of DNA fragments in polymer solution could be detected by a portable CE system integrated with PGD, with a limit of detection (LOD) comparable to that of the CE-ultraviolet (UV) method. Effects of buffer solution, sieving medium, and applied voltage were also investigated. The portable CE-PGD system shows several potential advantages, such as simplicity, cost effectiveness, and miniaturization.
Collapse
Affiliation(s)
- Yan Xu
- Department of Chemistry, National University of Singapore, Republic of Singapore
| | | | | |
Collapse
|
16
|
Yuan L, Wei H, Li SFY. Direct determination of gentamicin components by capillary electrophoresis with potential gradient detection. Electrophoresis 2005; 26:196-201. [PMID: 15624170 DOI: 10.1002/elps.200406121] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A simple and fast method was developed to determine non-UV active compounds directly without derivatization. The usefulness of the method was demonstrated by detecting the major components in aminoglycoside antibiotic mixtures using capillary zone electrophoresis with potential gradient detection. Under optimized separation conditions (0.2 mM cetyltrimethylammonium bromide (CTAB), 1 mM ammonium citrate, pH 3.5), gentamicin was separated into three major peaks (C1, C1a, and C2+C2a) within 15 min. This method showed better sensitivity than other capillary electrophoresis (CE) methods for determining underivatized gentamicin. The linear range was from 10 to 500 ppm. Because of its good repeatability and simplicity, this new method could be a good alternative for the current assays given by US Pharmacopoeia and European Pharmacopoeia.
Collapse
Affiliation(s)
- Lingling Yuan
- Department of Chemistry, National University of Singapore, Singapore, Republic of Singapore
| | | | | |
Collapse
|
17
|
Guijt RM, Evenhuis CJ, Macka M, Haddad PR. Conductivity detection for conventional and miniaturised capillary electrophoresis systems. Electrophoresis 2004; 25:4032-57. [PMID: 15597418 DOI: 10.1002/elps.200406156] [Citation(s) in RCA: 111] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Since the introduction of capillary electrophoresis (CE), conductivity detection has been an attractive means of detection. No additional chemical properties are required for detection, and no loss in sensitivity is expected when miniaturising the detector to scale with narrow-bore capillaries or even to the microchip format. Integration of conductivity and CE, however, involves a challenging combination of engineering issues. In conductivity detection the resistance of the solution is most frequently measured in an alternating current (AC) circuit. The influence of capacitors both in series and in parallel with the solution resistance should be minimised during conductivity measurements. For contact conductivity measurements, the positioning and alignment of the detection electrodes is crucial. A contact conductivity detector for CE has been commercially available, but was withdrawn from the market. Microfabrication technology enables integration and precise alignment of electrodes, resulting in the popularity of conductivity detection in microfluidic devices. In contactless conductivity detection, the alignment of the electrodes with respect to the capillary is less crucial. Contactless conductivity detection (CCD) was introduced in capillary CE, and similar electronics have been applied for CCD using planar electrodes in microfluidic devices. A contactless conductivity detector for capillaries has been commercialised recently. In this review, different approaches towards conductivity detection in capillaries and chip-based CE are discussed. In contrast to previous reviews, the focus of the present review is on the technological developments and challenges in conductivity detection in CE.
Collapse
Affiliation(s)
- Rosanne M Guijt
- Australian Centre for Research on Separation Science (ACROSS), University of Tasmania, School of Chemistry, Hobart, TAS, Australia
| | | | | | | |
Collapse
|
18
|
Abstract
This review as a sequel of three earlier similar reports gives a summary of the progress and significant methodological developments, starting from 2002, in the use of capillary electrophoresis (CE) for inorganic ion analysis. As substantiated by the illustrative number of relevant references, improvements in sensitivity achieved both in and outside a CE system, advances in manipulating the separation selectivity, novel hardware configurations, and system performance innovations are continually being reported over the review period. Specifically viewed are the recent advancements in elemental (bio)speciation analysis, which remains one of the most fertile areas of CE research, as well as in three recently booming research topics: contactless conductivity detection, separations on microchips, and transient isotachophoretic preconcentration. A state-of-the-art picture of technique's potentialities within the field of interest presented here demonstrates that CE has become recognized and is growing in acceptance as a reliable alternative to traditional analytical methods such as high-performance liquid chromatography (HPLC).
Collapse
Affiliation(s)
- Andrei R Timerbaev
- Vernadsky Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, Moscow, Russia.
| |
Collapse
|