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Kim K, Ju J, Kim B, Chung HY, Vetráková L, Heger D, Saiz-Lopez A, Choi W, Kim J. Nitrite-Induced Activation of Iodate into Molecular Iodine in Frozen Solution. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:4892-4900. [PMID: 30916540 DOI: 10.1021/acs.est.8b06638] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
A new mechanism for the abiotic production of molecular iodine (I2) from iodate (IO3-), which is the most abundant iodine species, in dark conditions was identified and investigated. The production of I2 in aqueous solution containing IO3- and nitrite (NO2-) at 25 °C was negligible. However, the redox chemical reaction between IO3- and NO2- rapidly proceeded in frozen solution at -20 °C, which resulted in the production of I2, I-, and NO3-. The rapid redox chemical reaction between IO3- and NO2- in frozen solution is ascribed to the accumulation of IO3-, NO2-, and protons in the liquid regions between ice crystals during freezing (freeze concentration effect). This freeze concentration effect was verified by confocal Raman microscopy for the solute concentration and UV-visible absorption spectroscopy with cresol red (acid-base indicator) for the proton concentration. The freezing-induced production of I2 in the presence of IO3- and NO2- was observed under various conditions, which suggests this abiotic process for I2 production is not restricted to a specific region and occurs in many cold regions. NO2--induced activation of IO3- to I2 in frozen solution may help explain why the measured values of iodine are larger than the modeled values in some polar areas.
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Affiliation(s)
- Kitae Kim
- Korea Polar Research Institute (KOPRI) , Incheon 21990 , Republic of Korea
- Department of Polar Sciences , University of Science and Technology (UST) , Incheon 21990 , Republic of Korea
| | - Jinjung Ju
- Department of Environmental Sciences and Biotechnology , Hallym University , Chuncheon , Gangwon-do 24252 , Republic of Korea
| | - Bomi Kim
- Korea Polar Research Institute (KOPRI) , Incheon 21990 , Republic of Korea
- Department of Polar Sciences , University of Science and Technology (UST) , Incheon 21990 , Republic of Korea
| | - Hyun Young Chung
- Korea Polar Research Institute (KOPRI) , Incheon 21990 , Republic of Korea
- Department of Polar Sciences , University of Science and Technology (UST) , Incheon 21990 , Republic of Korea
| | - L'ubica Vetráková
- Department of Chemistry and Research Centre for Toxic Compounds in the Environment (RECETOX), Faculty of Science , Masaryk University , Kamenice 5 , 625 00 Brno , Czech Republic
| | - Dominik Heger
- Department of Chemistry and Research Centre for Toxic Compounds in the Environment (RECETOX), Faculty of Science , Masaryk University , Kamenice 5 , 625 00 Brno , Czech Republic
| | - Alfonso Saiz-Lopez
- Department of Atmospheric Chemistry and Climate , Institute of Physical Chemistry Rocasolano, CSIC , Madrid 28006 , Spain
| | - Wonyong Choi
- Division of Environmental Science and Engineering , Pohang University of Science and Technology (POSTECH) , Pohang 37673 , Republic of Korea
| | - Jungwon Kim
- Department of Environmental Sciences and Biotechnology , Hallym University , Chuncheon , Gangwon-do 24252 , Republic of Korea
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Xie WQ, Yu KX, Gong YX. Determination of iodate in iodized edible salt based on a headspace gas chromatographic technique. J Chromatogr A 2019; 1584:187-191. [DOI: 10.1016/j.chroma.2018.12.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2018] [Revised: 12/01/2018] [Accepted: 12/09/2018] [Indexed: 01/31/2023]
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3
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Zhang YN, Yu H, Ma YJ, Cui G. Imidazolium ionic liquids as mobile phase additives in reversed phase liquid chromatography for the determination of iodide and iodate. Anal Bioanal Chem 2018; 410:7347-7355. [DOI: 10.1007/s00216-018-1347-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 08/25/2018] [Accepted: 08/28/2018] [Indexed: 12/20/2022]
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4
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Fukushi K, Fujita Y, Nonogaki J, Tsujimoto JI, Hattori T, Inui H, Beškoski VP, Hotta H, Hayashi M, Nakano T. Capillary zone electrophoresis determination of fluoride in seawater using transient isotachophoresis. Anal Bioanal Chem 2018; 410:1825-1831. [DOI: 10.1007/s00216-017-0838-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2017] [Revised: 12/11/2017] [Accepted: 12/15/2017] [Indexed: 10/18/2022]
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5
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Li Q, Li S, Chen X, Bian L. A G-quadruplex based fluorescent oligonucleotide turn-on probe towards iodides detection in real samples. Food Chem 2017; 230:432-440. [PMID: 28407932 DOI: 10.1016/j.foodchem.2017.03.062] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Revised: 02/02/2017] [Accepted: 03/11/2017] [Indexed: 01/23/2023]
Abstract
A basket-type G-quadruplex (GQ) fluorescent oligonucleotide (OND) probe is designed to detect iodides dependent on thymine-Hg(II)-thymine (T-Hg(II)-T) base pairs and the intrinsic fluorescence quenching capacity of GQ. In the presence of Hg(II) ions (Hg2+), the two hexachloro-fluorescein-labeled ONDs form a hairpin structure and the fluorophores are dragged close to the GQ, leading to fluorescence quenching of the probe due to photoinduced electron transfer. Upon addition of iodide anions, Hg2+ are extracted from T-Hg(II)-T complexes which attributes to the stronger binding with iodide anions, resulting in the fluorescence recovery. Through performing the fluorescence quenching and recovery processes, this probe developed a fluorescence turn-on sensor for iodide anions determination over a linear range of 20-200nmol/L with a limit of detection of 5nmol/L. The practical use of the turn-on technology was demonstrated by its application in determination of iodides in water, food, pharmaceutical products and biological samples.
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Affiliation(s)
- Qian Li
- College of Life Sciences, Northwest University, Xi'an 710069, Shaanxi, China
| | - Shuaihua Li
- College of Life Sciences, Northwest University, Xi'an 710069, Shaanxi, China
| | - Xiu Chen
- College of Life Sciences, Northwest University, Xi'an 710069, Shaanxi, China
| | - Liujiao Bian
- College of Life Sciences, Northwest University, Xi'an 710069, Shaanxi, China.
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6
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Yasuno K, Fukushi K. CZE determination of submicromolar level of phenol in seawater using improved dynamic pH junction. Electrophoresis 2016; 37:2496-2501. [DOI: 10.1002/elps.201600120] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2016] [Revised: 06/14/2016] [Accepted: 07/08/2016] [Indexed: 11/09/2022]
Affiliation(s)
- Koki Yasuno
- Kobe University Graduate School of Maritime Sciences; Kobe Japan
| | - Keiichi Fukushi
- Kobe University Graduate School of Maritime Sciences; Kobe Japan
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7
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HORIOKA Y, KUSUMOTO R, YAMANE K, NOMURA R, HIROKAWA T, ITO K. Determination of Inorganic Anions in Seawater Samples by Ion Chromatography with Ultraviolet Detection Using Monolithic Octadecylsilyl Columns Coated with Dodecylammonium Cation. ANAL SCI 2016; 32:1123-1128. [DOI: 10.2116/analsci.32.1123] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Yuuta HORIOKA
- Cluster of Biotechnology and Chemistry Systems, Graduate School of Systems Engineering, Kindai University
| | - Ryuki KUSUMOTO
- Department of Biotechnology and Chemistry, Faulty of Engineering, Kindai University
| | - Kengo YAMANE
- Cluster of Biotechnology and Chemistry Systems, Graduate School of Systems Engineering, Kindai University
| | - Ryosuke NOMURA
- Cluster of Biotechnology and Chemistry Systems, Graduate School of Systems Engineering, Kindai University
| | | | - Kazuaki ITO
- Cluster of Biotechnology and Chemistry Systems, Graduate School of Systems Engineering, Kindai University
- Department of Biotechnology and Chemistry, Faulty of Engineering, Kindai University
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8
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Abstract
The human body requires iodine to develop and maintain proper metabolic balance. Worldwide, iodine deficiency affects two billion people and is the leading preventable cause of intellectual disability. Small amounts of iodine are needed for good health. However, large doses can eventually cause iodide goitre, hypothyroidism or myxedema. Children are especially sensitive to the effects of iodine. Because humans can be exposed to iodide via several different food chains, the development of on-site, real-time and reliable sensors for iodide is of great interest to ensure early diagnosis and improve management. We propose here a simple and low cost, yet sensitive and selective fluorescent ‘turn-off-on’ assay for rapid determination of iodide based on a combined carbon nanodots (CDs) and Hg2+ system. The fluorescence of CDs that was quenched by Hg2+ was restored and ‘turned on’ in the presence of iodide, which triggered a competitive reaction among CDs, Hg2+ and iodide. The recovered fluorescence intensity varied linearly with the concentration of iodide in the range of 0.05–5 μmol L–1, with a limit of detection as low as 46 nmol L–1. This approach shows excellent selectivity for iodine over the other anions.
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9
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Sun J, Wang D, Cheng H, Liu J, Wang Y, Xu Z. Use of ion-pairing reagent for improving iodine speciation analysis in seaweed by pressure-driven capillary electrophoresis and ultraviolet detection. J Chromatogr A 2015; 1379:112-7. [DOI: 10.1016/j.chroma.2014.12.056] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Revised: 12/18/2014] [Accepted: 12/19/2014] [Indexed: 11/30/2022]
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10
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Zhang K, Liang L, Huang M, Hu Y, Li G. Determination of iodate in iodized salt and water samples by shell-isolated nanoparticle-enhanced Raman spectroscopy. Mikrochim Acta 2014. [DOI: 10.1007/s00604-014-1248-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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11
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Timerbaev AR. Element speciation analysis using capillary electrophoresis: twenty years of development and applications. Chem Rev 2012; 113:778-812. [PMID: 23057472 DOI: 10.1021/cr300199v] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Andrei R Timerbaev
- Vernadsky Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, Kosygin Str. 19, 119991 Moscow, Russian Federation.
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12
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Huang Z, Zhu Z, Subhani Q, Yan W, Guo W, Zhu Y. Simultaneous determination of iodide and iodate in povidone iodine solution by ion chromatography with homemade and exchange capacity controllable columns and column-switching technique. J Chromatogr A 2012; 1251:154-159. [DOI: 10.1016/j.chroma.2012.06.059] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2012] [Revised: 06/07/2012] [Accepted: 06/14/2012] [Indexed: 11/16/2022]
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13
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Abdolmohammad-Zadeh H, Tavarid K, Talleb Z. Determination of iodate in food, environmental, and biological samples after solid-phase extraction with Ni-Al-Zr ternary layered double hydroxide as a nanosorbent. ScientificWorldJournal 2012; 2012:145482. [PMID: 22619590 PMCID: PMC3349096 DOI: 10.1100/2012/145482] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2011] [Accepted: 12/15/2011] [Indexed: 11/17/2022] Open
Abstract
Nanostructured nickel-aluminum-zirconium ternary layered double hydroxide was successfully applied as a solid-phase extraction sorbent for the separation and pre-concentration of trace levels of iodate in food, environmental and biological samples. An indirect method was used for monitoring of the extracted iodate ions. The method is based on the reaction of the iodate with iodide in acidic solution to produce iodine, which can be spectrophotometrically monitored at 352 nm. The absorbance is directly proportional to the concentration of iodate in the sample. The effect of several parameters such as pH, sample flow rate, amount of nanosorbent, elution conditions, sample volume, and coexisting ions on the recovery was investigated. In the optimum experimental conditions, the limit of detection (3s) and enrichment factor were 0.12 μg mL(-1) and 20, respectively. The calibration graph using the preconcentration system was linear in the range of 0.2-2.8 μg mL(-1) with a correlation coefficient of 0.998. In order to validate the presented method, a certified reference material, NIST SRM 1549, was also analyzed.
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Affiliation(s)
- Hossein Abdolmohammad-Zadeh
- Department of Chemistry, Faculty of Sciences, Azarbaijan University of Tarbiat Moallem, 35 Km Tabriz-Marageh Road, P.O. Box 53714-161, 5375171379 Tabriz, Iran.
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14
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Nguyen BDQ, Chernov'yants MS, Burykin IV. In-capillary derivatization and determination of iodine in sodium chloride solution. Analyst 2012; 137:481-4. [DOI: 10.1039/c1an15932a] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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15
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Barman S, Sadhukhan M. Facile bulk production of highly blue fluorescent graphitic carbon nitride quantum dots and their application as highly selective and sensitive sensors for the detection of mercuric and iodide ions in aqueous media. ACTA ACUST UNITED AC 2012. [DOI: 10.1039/c2jm35501a] [Citation(s) in RCA: 361] [Impact Index Per Article: 30.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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16
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Mahapatra AK, Roy J, Sahoo P, Mukhopadhyay SK, Chattopadhyay A. Carbazole–thiosemicarbazone–Hg(ii) ensemble-based colorimetric and fluorescence turn-on toward iodide in aqueous media and its application in live cell imaging. Org Biomol Chem 2012; 10:2231-6. [DOI: 10.1039/c2ob06792g] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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17
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Iodide selective membrane electrodes based on a Molybdenum–Salen as a neutral carrier. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2011. [DOI: 10.1016/j.msec.2011.06.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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18
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Determination of iodide and iodate in edible salt by ion chromatography with integrated amperometric detection. Food Chem 2010. [DOI: 10.1016/j.foodchem.2010.04.046] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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19
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Direct injection of seawater for the analysis of nitroaromatic explosives and their degradation products by micellar electrokinetic chromatography. J Chromatogr A 2010; 1217:4487-93. [DOI: 10.1016/j.chroma.2010.04.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2010] [Revised: 03/29/2010] [Accepted: 04/08/2010] [Indexed: 11/23/2022]
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20
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Fukushi K, Yamazaki R, Yamane T. Determination of bromate in highly saline samples using CZE with on-line transient ITP. J Sep Sci 2009; 32:457-61. [DOI: 10.1002/jssc.200800502] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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21
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Wang T, Zhao S, Shen C, Tang J, Wang D. Determination of iodate in table salt by transient isotachophoresis–capillary zone electrophoresis. Food Chem 2009. [DOI: 10.1016/j.foodchem.2008.03.090] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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22
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Simpson SL, Quirino JP, Terabe S. On-line sample preconcentration in capillary electrophoresis. J Chromatogr A 2008; 1184:504-41. [DOI: 10.1016/j.chroma.2007.11.001] [Citation(s) in RCA: 269] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2007] [Revised: 10/30/2007] [Accepted: 11/01/2007] [Indexed: 02/06/2023]
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23
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Li H, Han C, Zhang L. Synthesis of cadmium selenide quantum dots modified with thiourea type ligands as fluorescent probes for iodide ions. ACTA ACUST UNITED AC 2008. [DOI: 10.1039/b806485g] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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24
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Chen JH, Wang KE, Jiang SJ. Determination of iodine and bromine compounds in foodstuffs by CE-inductively coupled plasma MS. Electrophoresis 2007; 28:4227-32. [DOI: 10.1002/elps.200700241] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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25
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Chen Y, Guo Z, Wang X, Qiu C. Sample preparation. J Chromatogr A 2007; 1184:191-219. [PMID: 17991475 DOI: 10.1016/j.chroma.2007.10.026] [Citation(s) in RCA: 252] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2007] [Revised: 10/08/2007] [Accepted: 10/10/2007] [Indexed: 11/17/2022]
Abstract
A panorama of sample preparation methods has been composed from 481 references, with a highlight of some promising methods fast developed during recent years and a somewhat brief introduction on most of the well-developed methods. All the samples were commonly referred to molecular composition, being extendable to particles including cells but not to organs, tissues and larger bodies. Some criteria to evaluate or validate a sample preparation method were proposed for reference. Strategy for integration of several methods to prepare complicated protein samples for proteomic studies was illustrated and discussed.
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Affiliation(s)
- Yi Chen
- Beijing National Laboratory of Molecular Science, Laboratory of Analytical Chemistry for Life Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China.
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26
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Pantůcková P, Urbánek M, Krivánková L. Determination of iodide in samples with complex matrices by hyphenation of capillary isotachophoresis and zone electrophoresis. Electrophoresis 2007; 28:3777-85. [PMID: 17893937 DOI: 10.1002/elps.200700189] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
A method has been developed for the determination of iodide in mineral water, seawater, cooking salt, serum, and urine based on hyphenation of capillary ITP and zone electrophoresis. A commercially available instrumentation for capillary ITP with column-switching system was used. ITP served for removal of chloride present in the analyzed samples in a ratio of 10(6)-10(7):1 to iodide, zone electrophoresis was used for evaluation. Isotachophoretic separation proceeded in a capillary made of fluorinated ethylene-propylene copolymer of 0.8 mm id and 90 mm total length to the bifurcation point filled with a leading electrolyte (LE) composed of 8 mM HCl + 16 mM beta-alanine (beta-Ala) + 10% PVP + 2.86 mM N(2)H(4)x2HCl, pH 3.2; and a terminating electrolyte composed of 8 mM H(3)PO(4) + 16 mM beta-Ala + 10% PVP + 5 mM N(2)H(4), pH 3.85 for all the matrices except seawater. For ITP of seawater the LE consisted of 50 mM HCl + 100 mM beta-Ala + 10% PVP + 2.86 mM N(2)H(4)x2HCl, pH 3.52. Distance of conductivity detector from the injection point and bifurcation point was 52 and 38 mm, respectively. Zone electrophoresis was performed in a capillary made of fused silica of 0.3 mm id and 160 mm total length filled with LE from isotachophoretic step. LODs reached for all matrices were 2-3x10(-8) M concentration (2.5-4 microg/L) enabled monitoring of iodide in all analyzed samples with RSD 0.4-9.3%. Estimated concentrations of iodide in individual matrices were 10(-6)-10(-8) M.
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Affiliation(s)
- Pavla Pantůcková
- Institute of Analytical Chemistry, Academy of Sciences of the Czech Republic, Brno, Czech Republic
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27
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Okamoto T, Fukushi K, Takeda S, Wakida SI. Determination of phosphate in seawater by CZE with on-line transient ITP. Electrophoresis 2007; 28:3447-52. [PMID: 17768722 DOI: 10.1002/elps.200700137] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
We developed CZE with indirect UV detection for the determination of phosphate in seawater using transient ITP as an on-line concentration procedure. The following optimum conditions were established: BGE, 5 mM 2,6-pyridinedicarboxylic acid (PDC) containing 0.01% hydroxypropylmethylcellulose (HPMC) adjusted to pH 3.5; detection wavelength, 200 nm; vacuum injection period of sample, 3 s (45 nL); terminating ion solution, 500 mM MES adjusted to pH 4.0; vacuum injection period of the terminating ion solution, 30 s (450 nL); applied voltage, 30 kV with the sample inlet side as the cathode. The LOD for phosphate was 16 microg/L (PO(3-)(4) -P) at S/N of 3. The respective values of the RSD of the peak area, peak height, and migration time for phosphate were 2.6, 2.3, and 0.34%. The proposed method was applied to the determination of phosphate in a seawater certified reference material for nutrients, MOOS-1, distributed by the National Research Council of Canada (NRC). The results were very similar to certified values. The method was also applied to the determination of phosphate in coastal seawaters. The results agreed with those obtained using a conventional spectrophotometric method.
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28
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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.
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Affiliation(s)
- Andrei R Timerbaev
- Vernadsky Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, Moscow, Russia.
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29
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Breadmore MC. Recent advances in enhancing the sensitivity of electrophoresis and electrochromatography in capillaries and microchips. Electrophoresis 2007; 28:254-81. [PMID: 17149782 DOI: 10.1002/elps.200600463] [Citation(s) in RCA: 160] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Poor sensitivity is considered to be one of the major limitations of electrophoretic separation methods, particularly when compared to traditional liquid chromatographic techniques. To address this issue, various in-line preconcentration techniques have been developed over the past 15 years, ranging in power and complexity, and there are now a number of well understood approaches routinely capable of providing a 10,000- to 100,000-fold increase in sensitivity, as well as several that can be pushed above a million. Furthermore, these have been achieved with particularly troublesome and often difficult samples, such as those having high salinity from a biological or environmental origin. This review will discuss the most common methods for improving the sensitivity of CE, CEC and microchip version of these, with particular attention to those approaches developed over the last five years.
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Affiliation(s)
- Michael C Breadmore
- Australian Centre for Research on Separation Science, School of Chemistry, University of Tasmania, Hobart, Tasmania, Australia.
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30
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Malá Z, Krivánková L, Gebauer P, Bocek P. Contemporary sample stacking in CE: A sophisticated tool based on simple principles. Electrophoresis 2007; 28:243-53. [PMID: 17136738 DOI: 10.1002/elps.200600397] [Citation(s) in RCA: 125] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Sample stacking is a general term for methods in CE which are used for on-line concentration of diluted analytes. During the stacking process, analytes present at low concentrations in a long injected sample zone are concentrated into a short zone (stack). The stacked analytes are then separated and individual zones are detected. Thus stacking provides better separation efficiency and detection sensitivity. Many papers have been published on stacking till now, various procedures have been described, and, many names have been proposed for stacking procedures utilizing the same principles. This contribution brings an easy and unified view on stacking, describes the basic principles utilized, makes a list of recognized operational principles and brings an overview of principal current procedures. Further, it surveys selected recent practical applications ordered according to their operational principles and includes the terms, nicknames, and acronyms used for these actual stacking procedures. This contribution may help both newcomers and experts in the field of CE to orient themselves in the already quite complex topic of sample stacking.
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Affiliation(s)
- Zdena Malá
- Institute of Analytical Chemistry, Academy of Sciences of the Czech Republic, Brno, Czech Republic
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31
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Petr J, Maier V, Horáková J, Sevcík J, Stránský Z. Capillary isotachophoresis from the student point of view – images and the reality. J Sep Sci 2006; 29:2705-15. [PMID: 17305231 DOI: 10.1002/jssc.200600249] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A review of some fundamental aspects of ITP from the student point of view, imaginations of some basic facts and laws, use of ITP, and the recent trends are presented. The results of theoretical computations of ITP separation processes are added for comparison of imaginations with the exact mathematical description.
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Affiliation(s)
- Jan Petr
- Department of Analytical Chemistrý, Palackỳ University, Trída Svobody 8, Olomouc, Czech Republic.
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Han Y, Zuo M, Qi L, Liu K, Mao L, Chen Y. Online acid barrage stacking anti-salt injection for capillary electrophoresis of 9-fluorenylmethylchloroformate-derivatized amino acids in high ionic strength solutions by UV detection. Electrophoresis 2006; 27:4240-8. [PMID: 17022015 DOI: 10.1002/elps.200600149] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
An acid barrage stacking (ABS) method has been shown to be feasible for online anti-salt injection in CE of 9-fluorenylmethyl chloroformate (FMOC)-labeled amino acids (AAs) detected by common UV absorption. The operation was performed on normal polar CE by sucking in an extra plug of acid following a sample zone, serving as a selective acid barrage to block the backward migration of weak anionic analytes due to a sudden mobility reduction via acid-base reaction which does not affect strong co-ions such as Cl(-) to penetrate the barrage freely. By CE-UV of FMOC-AAs in various NaCl solutions, the effectiveness of ABS was firmly validated, able to stand up to 500 mM NaCl and to stack analytes by 10(3)-fold calculated from the UV detection limits, that is 0.01 microM for ABS and 10 microM for non-stacking injection. The method was also validated by determining trace Glu and Asp in real samples of rat brain microdialysate, rat serum and human saliva. The intraday RSDs were 0.33-4.9% for migration time and 1.8-9.6% for peak area. The recoveries measured by spiking technique were 82-115% for Glu and 86-116% for Asp. Working equations were obtained by plotting peak height vs. concentration at 0.1-50 microM, with correlation coefficients of >0.999. The contents of Glu and Asp were thus found at 0.26-0.83 microM and 0.24-0.64 microM respectively, in rat brain microdialyste; 37-40 microM and 8.4-10 microM, respectively, in rat serum; and 3.5-5.8 microM and 1.0-4.1 microM, respectively in human saliva. They were consistent with the data from other methods.
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Affiliation(s)
- Yanli Han
- Beijing National Laboratory of Molecular Sciences, Laboratory of Analytical Chemistry for Life Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing , P R China
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Pereira FC, Moretto LM, De Leo M, Zanoni MVB, Ugo P. Gold nanoelectrode ensembles for direct trace electroanalysis of iodide. Anal Chim Acta 2006; 575:16-24. [PMID: 17723566 DOI: 10.1016/j.aca.2006.05.056] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2006] [Revised: 05/18/2006] [Accepted: 05/18/2006] [Indexed: 11/28/2022]
Abstract
A procedure for the standardization of ensembles of gold nanodisk electrodes (NEE) of 30 nm diameter is presented, which is based on the analytical comparison between experimental cyclic voltammograms (CV) obtained at the NEEs in diluted solutions of redox probes and CV patterns obtained by digital simulation. Possible origins of defects sometimes found in NEEs are discussed. Selected NEEs are then employed for the study of the electrochemical oxidation of iodide in acidic solutions. CV patterns display typical quasi-reversible behavior which involves associated chemical reactions between adsorbed and solution species. The main CV characteristics at the NEE compare with those observed at millimeter sized gold disk electrodes (Au-macro), apart a slight shift in E1/2 values and slightly higher peak to peak separation at the NEE. The detection limit (DL) at NEEs is 0.3 microM, which is more than one order of magnitude lower than DL at the Au-macro (4 microM). The mechanism of the electrochemical oxidation of iodide at NEEs is discussed. Finally, NEEs are applied to the direct determination of iodide at micromolar concentration levels in real samples, namely in some ophthalmic drugs and iodized table salt.
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Affiliation(s)
- Francisco C Pereira
- Department of Chemistry, Federal University of Rio Grande do Norte, 59072-970 Natal, RN, Brazil
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Dabek-Zlotorzynska E, Celo V. Recent advances in capillary electrophoresis and capillary electrochromatography of pollutants. Electrophoresis 2006; 27:304-22. [PMID: 16315167 DOI: 10.1002/elps.200500547] [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: 02/07/2023]
Abstract
Recent advances in the CE and CEC separation, detection, and sample preparation methodologies applied to the determination of a variety of compounds having current or potential environmental relevance have been overviewed. The reviewed literature has illustrated the wide range of CE applications, indicating the continuing interest in CE and CEC in the environmental field.
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Affiliation(s)
- Ewa Dabek-Zlotorzynska
- Analysis and Air Quality Division, Environmental Technology Centre, Environment Canada, Ottawa, Ontario, Canada.
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Riaz A, Chung DS. Calibration of migration times of variable salinity samples with internal standards in capillary electrophoresis. Electrophoresis 2006; 27:553-62. [PMID: 16380955 DOI: 10.1002/elps.200500595] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
A practical approach is presented for identifying the analyte peaks stacked by transient ITP (TITP) in samples of uncontrolled salinity. For TITP with chloride ions acting as the leading electrolyte, the effect of matrix chloride of an unknown concentration was calibrated using multiple internal standards to predict the migration times of weakly acidic anionic analytes behaving as strong electrolytes to an accuracy of over 99.9%. The calibration equations for the migration time of an analyte are given as a function of the migration times of internal standards using the mobilities of the relevant ions as parameters. The effects of matrix chloride and various separation conditions such as the temperature, plug length, ionic strength, and pH of the BGE were completely eliminated from the calibration equations. In addition, the actual mobilities, determined for a standard saline sample under the working conditions, were used, and thus, there was no need to conduct supplementary experiments to determine the absolute mobilities at infinite dilution. The internal standards were dyes, which were easily identified in an auxiliary channel monitoring the absorbance at a longer wavelength. For five standard saline matrices containing 100-300 mM NaCl at intervals of 50 mM, the mean absolute error (MAE) in migration times calibrated with two internal standards was 0.4 s (n=5x13). For an electropherogram of a real standard reference urine sample, peaks of spiked analytes were identified with an MAE of 0.9 s (n=13) without conductivity normalizing or desalting of the sample.
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Affiliation(s)
- Asif Riaz
- School of Chemistry, Seoul National University, Seoul, Korea
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Timerbaev AR, Hirokawa T. Recent advances of transient isotachophoresis-capillary electrophoresis in the analysis of small ions from high-conductivity matrices. Electrophoresis 2006; 27:323-40. [PMID: 16421955 DOI: 10.1002/elps.200500320] [Citation(s) in RCA: 117] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Since its invasion into the field of small ion analysis, quantitation of trace ionic analytes has always been a challenging task for CE, especially when dealing with highly saline samples. This review summarizes the method's progress and significant developments in the area due to its combination with on-line preconcentration by transient ITP (tITP). Principles of tITP stacking in high-conductivity solutions and operational preconcentration modes are considered. The most important application areas covered in this review include the analysis of seawater and biological fluids (urine, serum, etc.). Examples cited in this review demonstrate that tITP-CE is now on a certain way of becoming a recognized technique when the determination of trace ionic species in loaded matrices is the aim.
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Affiliation(s)
- Andrei R Timerbaev
- Vernadsky Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, Moscow, Russia
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OKAMOTO T, FUKUSHI K, YOKOTA K, TAKEDA S, WAKIDA SI. Determination of Phosphate in Seawater by Transient Isotachophoresis/Capillary Zone Electrophoresis with Suppressed Electroosmotic Flow. BUNSEKI KAGAKU 2006. [DOI: 10.2116/bunsekikagaku.55.627] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
| | | | - Kuriko YOKOTA
- Faculty of Crisis Management, Chiba Institute of Science
| | - Sahori TAKEDA
- National Institute of Advanced Industrial Science and Technology, AIST Kansai
| | - Shin-ichi WAKIDA
- National Institute of Advanced Industrial Science and Technology, AIST Kansai
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Fukushi K, Ito H, Kimura K, Yokota K, Saito K, Chayama K, Takeda S, Wakida SI. Determination of ammonium in river water and sewage samples by capillary zone electrophoresis with direct UV detection. J Chromatogr A 2005; 1106:61-6. [PMID: 16297395 DOI: 10.1016/j.chroma.2005.10.054] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2005] [Revised: 10/17/2005] [Accepted: 10/26/2005] [Indexed: 11/25/2022]
Abstract
We developed capillary zone electrophoresis (CZE) with direct UV detection for determination of ammonium in environmental water samples. Ammonium in the samples was partly converted into ammonia in the alkaline background electrolyte (BGE) during migration and was detected by molecular absorption of ammonia at 190 nm in approximately 7 min. The limit of detection (LOD) for ammonium was 0.24 mg/l (as nitrogen) at a signal-to-noise ratio of three. The respective values of the relative standard deviation (RSD) of peak area, peak height, and migration time for ammonium were 2.1, 1.8, and 0.46%. Major alkali and alkaline earth metal ions coexisting in the samples did not interfere with ammonium determination by the proposed method. The proposed method determined ammonium in surface water and sewage samples. The results were compared to those obtained using ion chromatography (IC).
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Affiliation(s)
- Keiichi Fukushi
- Faculty of Maritime Sciences, Kobe University, 5-1-1 Fukaeminami-machi, Kobe 658-0022, Japan.
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Liang L, Cai Y, Mou S, Cheng J. Comparisons of disposable and conventional silver working electrode for the determination of iodide using high-performance anion-exchange chromatography with pulsed amperometric detection. J Chromatogr A 2005; 1085:37-41. [PMID: 16106845 DOI: 10.1016/j.chroma.2004.12.060] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The paper compared the performance of two kinds of silver working electrode in electrochemical detector-the disposable and conventional electrode for the determination of iodide using high-performance anion-exchange chromatography (HPAEC) hyphenated with pulsed amperometric detection (PAD). The comparisons were carried out on the time of equilibration, long and short-term reproducibility, limits of detection and linearity of calibration. Results showed that disposable working electrode manifested equal or better results than conventional working electrode and could be used for iodide analysis. Besides, the disposable electrode could work for consecutive 2660 min (about 44 h, 10 min needed for each run) with no degradation. Due to its "disposable" property, disposable working electrode could be discarded if the detection sensitivity decreased to 80% so the time for polishing and reconditioning was spared and good reproducible results could be obtained. At last, the disposable electrode was applied for the determination of iodide in soil and sea water samples with the spiked recovery ranging from 96-104% and the detection limit of 0.5 microg/L (10 microL injection, three times of the baseline noise).
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Affiliation(s)
- Lina Liang
- Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P. O. Box 2871, Beijing 100085, China
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McReynolds JA, Gao L, Barber-Singh J, Shippy SA. Hadamard transform CE-UV detection for biological samples. J Sep Sci 2005; 28:128-36. [PMID: 15754819 DOI: 10.1002/jssc.200401923] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
A Hadamard transform-capillary electrophoresis-UV (HT-CE-UV) detection technique is described for the analysis of biological samples. Pseudorandom injections of sample and buffer according to a simplex matrix obtained from the corresponding Hadamard matrix is performed with conventional capillaries. Alternating injections are achieved with a novel capillary "T" connector created by drilling conventional capillary dimensions through a 1-cm diameter polycarbonate disc. This connector design coupled with a switching system allows for rapid, electrokinetic injections of solution into alternating sample and buffer capillary arms for UV detection. The standard mixtures of nitric oxide (NO) metabolites, nitrite and nitrate, dissolved in physiological saline solution are injected into the separation capillary according to an 83-element injection sequence to obtain a signal-to-noise ratio (S/N) enhancement of ca. 4.5 over a single injection. Nitrite, being the less concentrated metabolite in NO detection and thereby more difficult to detect, was calibrated with the HT-CE-UV method and a limit of detection (LOD) of 0.56 microM was obtained. Rat blood plasma was analyzed with this detection system and demonstrated to be comparable with NO metabolite concentrations of previously published results. This HT-CE-UV method is described where a unique reservoir tube design that contains 8-microL standard nitrite sample volumes is placed over the end of the capillary arm to explore low volume limits for biological samples.
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Affiliation(s)
- Jennifer A McReynolds
- Department of Chemistry (M/C 111), University of Illinois at Chicago, Chicago, Illinois 60607-7061, USA
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Huang Z, Ito K, Morita I, Yokota K, Fukushi K, Timerbaev AR, Watanabe S, Hirokawa T. Sensitive monitoring of iodine species in sea water using capillary electrophoresis: vertical profiles of dissolved iodine in the Pacific Ocean. ACTA ACUST UNITED AC 2005; 7:804-8. [PMID: 16049582 DOI: 10.1039/b501398d] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Using a novel high-sensitivity capillary electrophoretic method, vertical distributions of iodate, iodide, total inorganic iodine, dissolved organic iodine and total iodine in the North Pacific Ocean (0-5500 m) were determined without any sample pre-treatment other than UV irradiation before total iodine analysis. An extensive set of data demonstrated that the iodine behaviour in the ocean water collected during a cruise in the North Pacific Ocean in February-March 2003 was not conservative but correlated with variations in concentrations of dissolved oxygen and nutrient elements such as silicon, nitrogen and phosphorus. This suggests that the vertical distribution of iodine is associated with biological activities. The dissolved organic iodine was found in the euphotic zone in accord with observations elsewhere in the oceans. The vertical profile of dissolved organic iodine also appears to be related to biogeochemical activity. The concentrations of all measured iodine species vary noticeably above 1000 m but only minor latitudinal changes occur below 1000 m and slight vertical alterations can be observed below 2400 m. These findings are thought to reflect the stratification of nutrients and iodine species with different biological activities in the water column.
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Affiliation(s)
- Zhuo Huang
- Department of Applied Chemistry, Graduate School of Engineering, Hiroshima University, Higashi-hiroshima, Japan
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FUKUSHI K, YOKOTA K, NAKAYAMA Y, ISHIO N, MIYADO T. Determination of Trace Inorganic Anions in Seawater by Capillary Zone Electrophoresis with Artificial Seawater as Background Electrolyte. BUNSEKI KAGAKU 2005. [DOI: 10.2116/bunsekikagaku.54.665] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
| | - Kuriko YOKOTA
- Faculty of Maritime Sciences, Kobe University
- Present address, Faculty of Crisis Management, Chiba Institute of Science
| | - Yusuke NAKAYAMA
- Faculty of Maritime Sciences, Kobe University
- Present address, Arkray, Inc
| | | | - Takashi MIYADO
- Faculty of Maritime Sciences, Kobe University
- Present address, National Institute of Advanced Industrial Science and Technology, AIST Kansai
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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).
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Affiliation(s)
- Andrei R Timerbaev
- Vernadsky Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, Moscow, Russia.
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Huang Z, Ito K, Hirokawa T. Further research on iodine speciation in seawater by capillary zone electrophoresis with isotachophoresis preconcentration. J Chromatogr A 2004; 1055:229-34. [PMID: 15560501 DOI: 10.1016/j.chroma.2004.09.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
A novel, simple and highly sensitive CE method was developed to determine total iodine (TI) in seawater. The method is based on the on-capillary reduction of iodine species to iodide by a reductant, introduced into the capillary before sample injection, the preconcentration of iodide using isotachophoresis, followed by its UV detection. Under optimized conditions for reduction and CE separation, the limit of detection for TI (S/N = 3) reached 0.4 microg L(-1) (226 nm). The repeatability of migration time and peak area, expressed by relative standard deviation, was 0.46 and 1.45%, respectively (n = 19). The correlation factor was 0.9991 (n = 10) for the concentration range of 12-115 microg I L(-1). The CE results obtained for the real seawater analysis agreed with the data of ion chromatography. To determine the genuine TI by the proposed method, organic iodinated compounds in the sample were treated with H202 and irradiation with UV light before analysis.
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Affiliation(s)
- Zhuo Huang
- Department of Applied Chemistry, Graduate School of Engineering, Hiroshima University, Higashi-Hiroshima 739-8527, Japan
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