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Monsef Khoshhesab Z, Divsar F. Nickel Ferrite Magnetic Nanoparticles as a Sorbent for Solid Phase Extraction of Trace Lead from Water Prior to Spectrophotometric Determination. JOURNAL OF ANALYTICAL CHEMISTRY 2019. [DOI: 10.1134/s1061934819040087] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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2
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Rathod T, Tiwari M, Maity S, Sahu S, Pandit G. Multi-element detection in sea water using preconcentration procedure and EDXRF technique. Appl Radiat Isot 2018; 135:57-60. [DOI: 10.1016/j.apradiso.2018.01.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 11/22/2017] [Accepted: 01/12/2018] [Indexed: 11/28/2022]
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3
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Khaled EM, Meguid NA, Bjørklund G, Gouda A, Bahary MH, Hashish A, Sallam NM, Chirumbolo S, El-Bana MA. Altered urinary porphyrins and mercury exposure as biomarkers for autism severity in Egyptian children with autism spectrum disorder. Metab Brain Dis 2016; 31:1419-1426. [PMID: 27406246 DOI: 10.1007/s11011-016-9870-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Accepted: 06/30/2016] [Indexed: 12/11/2022]
Abstract
Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder that affects social, communication, and behavioral development. Recent evidence supported but also questioned the hypothetical role of compounds containing mercury (Hg) as contributors to the development of ASD. Specific alterations in the urinary excretion of porphyrin-containing ring catabolites have been associated with exposure to Hg in ASD patients. In the present study, the level of urinary porphyrins, as biomarkers of Hg toxicity in children with ASD, was evaluated, and its correlation with severity of the autistic behavior further explored. A total of 100 children was enrolled in the present study. They were classified into three groups: children with ASD (40), healthy controls (40), and healthy siblings of the ASD children (20). Children with ASD were diagnosed using DSM-IV-TR, ADI-R, and CARS tests. Urinary porphyrins were evaluated within the three groups using high-performance liquid chromatography (HPLC), after plasma evaluation of mercury (Hg) and lead (Pb) in the same groups. Results showed that children with ASD had significantly higher levels of Hg, Pb, and the porphyrins pentacarboxyporphyrin, coproporphyrin, precoproporphyrin, uroporphyrins, and hexacarboxyporphyrin compared to healthy controls and healthy siblings of the ASD children. However, there was no significant statistical difference in the level of heptacarboxyporphyrin among the three groups, while a significant positive correlation between the levels of coproporphyrin and precoproporphyrin and autism severity was observed. Mothers of ASD children showed a higher percentage of dental amalgam restorations compared to the mothers of healthy controls suggesting that high Hg levels in children with ASD may relate to the increased exposure to Hg from maternal dental amalgam during pregnancy and lactation. The results showed that the ASD children in the present study had increased blood Hg and Pb levels compared with healthy control children indicating that disordered porphyrin metabolism might interfere with the pathology associated with the autistic neurologic phenotype. The present study indicates that coproporphyrin and precoproporhyrin may be utilized as possible biomarkers for heavy metal exposure and autism severity in children with ASD.
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Affiliation(s)
- Eman M Khaled
- Department of Pediatric, Al-Azhar University, Cairo, Egypt
| | - Nagwa A Meguid
- Department of Research on Children with Special Needs, National Research Centre, Giza, Egypt
| | - Geir Bjørklund
- Council for Nutritional and Environmental Medicine, Toften 24, 8610, Mo i Rana, Norway.
| | - Amr Gouda
- Department of Genetic Biochemistry, National Research Centre, Giza, Egypt
| | | | - Adel Hashish
- Department of Research on Children with Special Needs, National Research Centre, Giza, Egypt
| | - Nermin M Sallam
- Department of Research on Children with Special Needs, National Research Centre, Giza, Egypt
| | - Salvatore Chirumbolo
- University Laboratory of Medical Research, Department of Medicine, University of Verona, Verona, Italy
| | - Mona A El-Bana
- Department of Medical Biochemistry, National Research Centre, Giza, Egypt
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4
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Abstract
A dynamic development of methodologies of analytical flow injection measurements during four decades since their invention has reinforced the solid position of flow analysis in the arsenal of techniques and instrumentation of contemporary chemical analysis.
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Affiliation(s)
- Marek Trojanowicz
- Laboratory of Nuclear Analytical Methods
- Institute of Nuclear Chemistry and Technology
- 03-195 Warsaw
- Poland
- Department of Chemistry
| | - Kamila Kołacińska
- Laboratory of Nuclear Analytical Methods
- Institute of Nuclear Chemistry and Technology
- 03-195 Warsaw
- Poland
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5
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Marguí E, Zawisza B, Sitko R. Trace and ultratrace analysis of liquid samples by X-ray fluorescence spectrometry. Trends Analyt Chem 2014. [DOI: 10.1016/j.trac.2013.09.009] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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6
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Miró M, Hansen EH. On-line sample processing involving microextraction techniques as a front-end to atomic spectrometric detection for trace metal assays: a review. Anal Chim Acta 2013; 782:1-11. [PMID: 23708278 DOI: 10.1016/j.aca.2013.03.019] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2012] [Revised: 02/22/2013] [Accepted: 03/08/2013] [Indexed: 12/24/2022]
Abstract
Within the last decade, liquid-phase microextraction (LPME) and micro-solid phase extraction (μSPE) approaches have emerged as substitutes for conventional sample processing procedures for trace metal assays within the framework of green chemistry. This review surveys the progress of the state of the art in simplification and automation of microextraction approaches by harnessing to the various generations of flow injection (FI) as a front end to atomic absorption spectrometry (AAS), atomic fluorescence spectrometry (AFS) or inductively coupled plasma atomic emission spectrometry or mass spectrometry (ICP-AES/MS). It highlights the evolution of flow injection analysis and related techniques as vehicles for appropriate sample presentation to the detector and expedient on-line matrix separation and pre-concentration of trace levels of metals in troublesome matrices. Rather than being comprehensive this review is aimed at outlining the pros and cons via representative examples of recent attempts in automating green sample preparation procedures in an FI or sequential injection (SI) mode capitalizing on single-drop microextraction, dispersive liquid-phase microextraction and advanced sorptive materials including carbon and metal oxide nanoparticles, ion imprinted polymers, superparamagnetic nanomaterials and biological/biomass sorbents. Current challenges in the field are identified and the synergetic combination of flow analysis, nanotechnology and metal-tagged biomolecule detection is envisaged.
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Affiliation(s)
- Manuel Miró
- FI-TRACE Group, Department of Chemistry, Faculty of Sciences, University of the Balearic Islands, E-07122 Palma de Mallorca, Illes Balears, Spain.
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Chen J, Cao J, Gao W, Qi LW, Li P. Environmentally friendly ionic liquid-in-water microemulsions for extraction of hydrophilic and lipophilic components from Flos Chrysanthemi. Analyst 2013; 138:5933-41. [DOI: 10.1039/c3an00957b] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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8
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Anthemidis AN, Tsartsidou MS, Stratis JA. Sequential Injection On-Line Sorption Preconcentration Using PEEK-Turnings Packed Micro-Column for Ultra-Trace Cobalt Determination by Electrothermal Atomic Absorption Spectrometry. ANAL LETT 2012. [DOI: 10.1080/00032719.2011.649449] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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9
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Yu HM, Song H, Chen ML. Dithizone immobilized silica gel on-line preconcentration of trace copper with detection by flame atomic absorption spectrometry. Talanta 2011; 85:625-30. [PMID: 21645750 DOI: 10.1016/j.talanta.2011.04.039] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2010] [Revised: 04/08/2011] [Accepted: 04/12/2011] [Indexed: 11/29/2022]
Abstract
A novel adsorbent-silica gel bound dithizone (H(2)Dz-SG) was prepared and used as solid-phase extraction of copper from complex matrix. The H(2)Dz-SG is investigated by means of FT-IR spectra and the SEM images, demonstrating the bonding of dithizone. The H(2)Dz-SG quantitatively adsorb copper ions, and the retained copper is afterwards collected by elution of 10% (v/v) nitric acid. An on-line flow injection solid-phase extraction procedure was developed for trace copper separation and preconcentration with detection by flame atomic spectrometry. By loading 5.4 mL of sample solution, a liner range of 0.5-120 μg L(-1), an enrichment factor of 42.6, a detection limit of 0.2 μg L(-1) and a precision of 1.7% RSD at the 40 μg L(-1) level (n=11) were obtained, along with a sampling frequency of 47 h(-1). The dynamic sorption capacity of H(2)Dz-SG to Cu(2+) was 0.76 mg g(-1). The accuracy of the proposed procedure was evaluated by determination of copper in reference water sample. The potential applications of the procedure for extraction of trace copper were successfully accomplished in water samples (tap, rain, snow, sea and river). The spiking recoveries within 91-107% are achieved.
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Affiliation(s)
- Hong-Mei Yu
- Research Center for Analytical Sciences, College of Sciences, Northeastern University, Shenyang 110819, China
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Berton P, Wuilloud RG. An online ionic liquid-based microextraction system coupled to electrothermal atomic absorption spectrometry for determination in environmental samples and pharmaceutical formulations. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2011; 3:664-672. [PMID: 32938088 DOI: 10.1039/c0ay00616e] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
In the present work, an ionic liquid (IL) lighter than water was employed as extraction solvent in a dispersive liquid-liquid microextraction (DLLME) methodology. An original flow injection system for online microextraction and preconcentration of cobalt (Co) based on the use of tetradecyl(trihexyl)phosphonium chloride (CYPHOS® IL 101) was designed. Cobalt was complexed with 4-(2-pyridylazo)-resorcinol (PAR) reagent at pH 4.8 and then, the IL-DLLME procedure was developed by dispersing CYPHOS® IL 101 with acetone in an aqueous solution containing Co-PAR complex. Different pyridylazo dyes were evaluated for Co preconcentration in terms of their molecular structure, stability and acid-base equilibrium. Online extraction of Co-PAR into the IL and separation of the dispersed IL enriched phase were accomplished with a microcolumn containing Florisil material. Cobalt was removed from the microcolumn with a 10% (v/v) HNO3 acidified-acetone solution and finally measured by electrothermal atomic absorption spectrometry (ETAAS). The detection limit achieved after preconcentration of 2 mL of sample solution was 8 ng L-1. The precision for 10 replicate determinations at the 1 µg L-1 Co level was 5.1% relative standard deviation (RSD), calculated from the peak heights obtained. The method was successfully applied to Co determination in water samples as well as ophthalmic and parenteral solutions. For the first time, an IL-based microextraction technique was applied for metal determination in these complex samples, where Co recovery varied between 97.9 and 103%.
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Affiliation(s)
- Paula Berton
- Analytical Chemistry Research and Development Group (QUIANID), (LISAMEN-CCT-CONICET-Mendoza), Av. Ruiz Leal S/N Parque General San Martín, M 5502 IRA, Mendoza, Argentina.
| | - Rodolfo G Wuilloud
- Analytical Chemistry Research and Development Group (QUIANID), (LISAMEN-CCT-CONICET-Mendoza), Av. Ruiz Leal S/N Parque General San Martín, M 5502 IRA, Mendoza, Argentina.
- Instituto de Ciencias Básicas, Universidad Nacional de Cuyo, Mendoza, Argentina
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11
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Nageswara Rao R, Ramachandra B, Mastan Vali R. Reversed-phase liquid chromatographic separation of antiretroviral drugs on a monolithic column using ionic liquids as mobile phase additives. J Sep Sci 2011; 34:500-7. [DOI: 10.1002/jssc.201000723] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2010] [Revised: 12/08/2010] [Accepted: 12/11/2010] [Indexed: 01/07/2023]
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12
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Pinto PCAG, Lúcia M, Saraiva MFS, Lima JLFC. Sequential Injection Analysis Hyphenated with Other Flow Techniques: A Review. ANAL LETT 2011. [DOI: 10.1080/00032719.2010.500780] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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13
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Chen XW, Chen ML, Chen S, Wang JH. Flow-based analysis: a versatile, powerful platform for DNA assays. Trends Analyt Chem 2008. [DOI: 10.1016/j.trac.2008.07.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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14
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Su CK, Li TW, Sun YC. Online In-Tube Solid-Phase Extraction Using a Nonfunctionalized PVC Tube Coupled with ICPMS for in Vivo Monitoring of Trace Metals in Rat Brain Microdialysates. Anal Chem 2008; 80:6959-67. [DOI: 10.1021/ac800802e] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- C. K. Su
- Department of Biomedical Engineering and Environmental Sciences and Nuclear Science and Technology Development Center, National Tsing-Hua University, 30013 Hsinchu, Taiwan
| | - T. W. Li
- Department of Biomedical Engineering and Environmental Sciences and Nuclear Science and Technology Development Center, National Tsing-Hua University, 30013 Hsinchu, Taiwan
| | - Y. C. Sun
- Department of Biomedical Engineering and Environmental Sciences and Nuclear Science and Technology Development Center, National Tsing-Hua University, 30013 Hsinchu, Taiwan
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16
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NUKATSUKA I, OSANAI S, OHZEKI K. Preparation of Open Tubular Solid-Phase Extraction Column with 5-Amino-8-hydroxyquinoline-modified Gold Nanoparticle Phase for the Enrichment of Heavy Metal Ions. ANAL SCI 2008; 24:267-71. [DOI: 10.2116/analsci.24.267] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Isoshi NUKATSUKA
- Department of Materials Science and Technology, Graduate School of Science and Technology, Hirosaki University
| | - Shigeaki OSANAI
- Department of Materials Science and Technology, Graduate School of Science and Technology, Hirosaki University
| | - Kunio OHZEKI
- Department of Materials Science and Technology, Graduate School of Science and Technology, Hirosaki University
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17
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Zou AM, Chen ML, Chen XW, Wang JH. Cell-sorption of paramagnetic metal ions on a cell-immobilized micro-column in the presence of an external magnetic field. Anal Chim Acta 2007; 598:74-81. [PMID: 17693309 DOI: 10.1016/j.aca.2007.07.022] [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] [Received: 07/05/2007] [Accepted: 07/10/2007] [Indexed: 11/19/2022]
Abstract
The cell-sorption of paramagnetic ions of Mn2+ and Cr3+ onto a Chlorella vulgaris (C. vulgaris) cell-immobilized micro-column was significantly improved in the presence of an external magnetic field generated in a finite solenoid, by placing the micro-column in the center of the solenoid in a sequential injection system. Magnetic field creates an opposite drift velocity on the hydrated paramagnetic ions against the flow of the sample zone, retards the moving velocity of the metal ions and provides extra contacting time with the cells on the micro-column and offers more chances for the paramagnetic ions to interact with the various functional groups or binding sites on the cell surface, which significantly facilitates cell-sorption of the paramagnetic ions. The sorption efficiencies of Mn2+ and Cr3+ at the 20 microg L(-1) level were improved from 45 to 80% and 60 to 90%, respectively, in a magnetic field of 240 mT. The system was applied for the separation/preconcentration of ultra-trace level of manganese. The presence of an external magnetic field significantly alleviated the interfering effects from coexisting metal ions. Within a liner range of 0.025-0.5 microg L(-1) and a sampling volume of 500 microL, an enrichment factor of 21.2, a limit of detection of 0.008 microg L(-1), along with a sampling frequency of 20 h(-1) was attained, achieving a precision of 2.1% R.S.D. (0.2 microg L(-1)). Manganese contents in a certified reference material of riverine water and a snow water were analyzed.
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Affiliation(s)
- Ai-Mei Zou
- Research Center for Analytical Sciences, Northeastern University, Box 332, Shenyang 110004, China
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18
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Erxleben H, Ruzicka J. Atomic absorption spectroscopy for mercury, automated by sequential injection and miniaturized in lab-on-valve system. Anal Chem 2007; 77:5124-8. [PMID: 16097748 DOI: 10.1021/ac058007s] [Citation(s) in RCA: 133] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Sodium borohydride-based hydride generation was automated by using programmable flow within the lab-on-valve module. Mercury vapor, generated in the reaction mixture, was extracted in a gas/liquid separator. The gas-expansion separator was miniaturized and compared with the performance of a novel gas separator that exploits the combination of Venturi effect and reduced pressure. Cold vapor atomic spectroscopy was used as a model system, with detection of mercury by absorption at 254 nm and limit of detection of 9 microg of Hg/L, using 300 microL of sample and 100 microL of borohydride. This work introduces, for the first time, sequential injection technique for hydride generation, highlights advantages of using programmable flow, and outlines means for miniaturization of assays based on spectroscopy of volatile species.
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Affiliation(s)
- Holger Erxleben
- Department of Chemistry, University of Washington, Box 351700, Seattle, WA 98195-1700, USA
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19
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Amorim FAC, Bezerra MA. Online preconcentration system for determining ultratrace amounts of Cd in vegetal samples using thermospray flame furnace atomic absorption spectrometry. Mikrochim Acta 2007. [DOI: 10.1007/s00604-006-0713-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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20
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Pyrzynska K. Online Sample Pretreatment Systems for Determination of Cadmium by the ETAAS Method. Crit Rev Anal Chem 2007. [DOI: 10.1080/10408340600976473] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Krystyna Pyrzynska
- a Department of Chemistry , University of Warsaw, Pasteura 1 , Warsaw, 02-093, Poland
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21
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Hansen EH, Miró M. How flow-injection analysis (FIA) over the past 25 years has changed our way of performing chemical analyses. Trends Analyt Chem 2007. [DOI: 10.1016/j.trac.2006.07.010] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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22
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Octadecyl immobilized silica beads packed microcolumn versus PTFE knotted reactor as Cd(OH)2 precipitate collection media coupled to ETAAS for cadmium determination. CHINESE JOURNAL OF ANALYTICAL CHEMISTRY 2006. [DOI: 10.1016/s1872-2040(06)60051-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Hansen EH, Miró M, Long X, Petersen R. Recent Developments in Automated Determinations of Trace Level Concentrations of Elements and On‐Line Fractionation Schemes Exploting the Micro‐Sequential Injection—Lab‐On‐Valve Approach. ANAL LETT 2006. [DOI: 10.1080/00032710600665943] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Long X, Miró M, Jensen R, Hansen EH. Highly selective micro-sequential injection lab-on-valve (μSI-LOV) method for the determination of ultra-trace concentrations of nickel in saline matrices using detection by electrothermal atomic absorption spectrometry. Anal Bioanal Chem 2006; 386:739-48. [PMID: 16724222 DOI: 10.1007/s00216-006-0467-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2006] [Revised: 03/24/2006] [Accepted: 04/04/2006] [Indexed: 10/24/2022]
Abstract
A highly selective procedure is proposed for the determination of ultra-trace level concentrations of nickel in saline aqueous matrices exploiting a micro-sequential injection Lab-On-Valve (muSI-LOV) sample pretreatment protocol comprising bead injection separation/pre-concentration and detection by electrothermal atomic absorption spectrometry (ETAAS). Based on the dimethylglyoxime (DMG) reaction used for nickel analysis, the sample, as contained in a pH 9.0 buffer, is, after on-line merging with the chelating reagent, transported to a reaction coil attached to one of the external ports of the LOV to assure sufficient reaction time for the formation of Ni(DMG)(2) chelate. The non-ionic coordination compound is then collected in a renewable micro-column packed with a reversed-phase copolymeric sorbent [namely, poly(divinylbenzene-co-N-vinylpyrrolidone)] containing a balanced ratio of hydrophilic and lipophilic monomers. Following elution by a 50-muL methanol plug in an air-segmented modality, the nickel is finally quantified by ETAAS. Under the optimized conditions and for a sample volume of 1.8 mL, a retention efficiency of 70 % and an enrichment factor of 25 were obtained. The proposed methodology showed a high tolerance to the commonly encountered alkaline earth matrix elements in environmental waters, that is, calcium and magnesium, and was successfully applied for the determination of nickel in an NIST standard reference material (NIST 1640-Trace elements in natural water), household tap water of high hardness and local seawater. Satisfying recoveries were achieved for all spiked environmental water samples with maximum deviations of 6 %. The experimental results for the standard reference material were not statistically different to the certified value at a significance level of 0.05.
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Affiliation(s)
- Xiangbao Long
- Department of Chemistry, Technical University of Denmark, Kemitorvet, Building 207, 2800, Kgs. Lyngby, Denmark
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25
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Wan Z, Xu Z, Wang J. Flow injection on-line solid phase extraction for ultra-trace lead screening with hydride generation atomic fluorescence spectrometry. Analyst 2006; 131:141-7. [PMID: 16365675 DOI: 10.1039/b511829h] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A flow injection (FI) on-line solid phase extraction (SPE) procedure for ultra-trace lead separation and preconcentration was developed, followed by hydride generation and atomic fluorescence spectrometric (AFS) detection. Lead is retained on an iminodiacetate chelating resin packed microcolumn, and is afterward eluted with 2.5% (v/v) hydrochloric acid to facilitate the hydride generation by reaction with alkaline tetrahydroborate solution with 1% (m/v) potassium ferricyanide as an oxidizing (or sensitizing) reagent. The hydride was separated from the reaction medium in the gas-liquid separator and swept into the atomizer for quantification. The chemical variables and the FI flow parameters were carefully optimized. With a sample loading volume of 4.8 ml, quantitative retention of lead was obtained, along with an enrichment factor of 11.3 and a sampling frequency of 50 h(-1). A detection limit of 4 ng l(-1), defined as 3 times the blank standard deviation (3 sigma), was achieved along with a RSD value of 1.6% at the 0.4 microg l(-1) level. The procedure was validated by determining lead contents in two certified reference materials, and its practical applicability was further demonstrated by analysing a variety of biological and environmental samples.
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Affiliation(s)
- Zhuo Wan
- Research Center for Analytical Sciences, Box 332, Northeastern University, Shenyang 110004, China
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Kulka S, Quintás G, Lendl B. Automated sample preparation and analysis using a sequential-injection–capillary electrophoresis (SI–CE) interface. Analyst 2006; 131:739-44. [PMID: 16732362 DOI: 10.1039/b517162h] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A fully automated sequential-injection-capillary electrophoresis (SI-CE) system was developed using commercially available components as the syringe pump, the selection and injection valves and the high voltage power supply. The interface connecting the SI with the CE unit consisted of two T-pieces, where the capillary was inserted in one T-piece and a Pt electrode in the other (grounded) T-piece. By pressurising the whole system using a syringe pump, hydrodynamic injection was feasible. For characterisation, the system was applied to a mixture of adenosine and adenosine monophosphate at different concentrations. The calibration curve obtained gave a detection limit of 0.5 microg g(-1) (correlation coefficient of 0.997). The reproducibility of the injection was also assessed, resulting in a RSD value (5 injections) of 5.4%. The total time of analysis, from injection, conditioning and separation to cleaning the capillary again was 15 minutes. In another application, employing the full power of the automated SIA-CE system, myoglobin was mixed directly using the flow system with different concentrations of sodium dodecyl sulfate (SDS), a known denaturing agent. The different conformations obtained in this way were analysed with the CE system and a distinct shift in migration time and decreasing of the native peak of myoglobin (Mb) could be observed. The protein samples prepared were also analysed with off-line infrared spectroscopy (IR), confirming these results.
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Affiliation(s)
- Stephan Kulka
- Institute for Chemical Technologies and Analytics, Vienna University of Technology, Getreidemarkt 9-164, Vienna, A-1060, Austria
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27
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Hansen EH. Use of flow injection and sequential injection analysis schemes for the determination of trace-level concentrations of metals in complex matrices by ETAAS and ICPMS. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2005; 40:1507-24. [PMID: 15991720 DOI: 10.1081/ese-200060600] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Despite their excellent analytical chemical capacities for determination of low levels of metal species, electrothermal atomic absorption spectrometry and inductively coupled plasma mass spectrometry often require suitable pretreatment (separation and preconcentration) of the sample material to facilitate the desired sensitivity and selectivity of measurement. Such pretreatment schemes are advantageously performed in flow injection (FI) or sequential injection (SI) manifolds, where all unit operations can be effected on-line and under enclosed and strictly controlled conditions. Various separation/preconcentration procedures are feasible, such as liquid-liquid extraction (possibly including back extraction), (co)precipitation with collection in knotted coils, adsorption on hydrophilic or hydrophobic reactors, hydride generation, or the use of ion-exchange/chelating packed columns. After describing the particulars and characteristics of FI and SI, we present, via selected examples, various separation/preconcentration FI/SI schemes for the determination of trace levels of metals, with particular emphasis on the use of the novel extension of FI/SI, that is, the so-called lab-on-valve concept.
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Affiliation(s)
- Elo Harald Hansen
- Department of Chemistry, Technical University of Denmark, Kemitorvet, Kgs. Lyngby, Denmark.
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