Determination and speciation

Tutschku S, Mothes S, Dittrich K (1994) Determination and speciation of organotin compounds by gas chromatography-microwave induced plasma atomic emission spectrometry. Journal of Chromatography A, 683 269-276. 

HPLC (in both NP and RP modes) is quite suitable for speciation by coupling to FAAS, ETAAS, ICP-MS and MIP-MS [571,572]. Coupling of plasma source mass spectrometry with chromatographic techniques offers selective detection with excellent sensitivity. For HPLC-ICP-MS detection limits are in the sub-ng to pg range [36]. Metal ion determination and speciation by LC have been reviewed [573,574] with particular regard to ion chromatography [575]. 

Supersaturation of up to nearly 4 orders of magnitude is indicated relative to a log K= 4.9 which reflects freshly precipitated HFO. When elimination of all data points which are below the detection limits for Fe(lll) and for electrode measurements, values of Eh measured agree with Eh calculated from Fe(ll/lll) determinations and speciation calculations and the revised ferrihydrite saturation index diagram looks like fig. 3. 

K. G. Heumann. Isotope-dilution ICP-MS for Trace Element Determination and Speciation From a Reference Method to a Routine Method Anal. Bioanal. Chem., 378(2004) 318-329. 

Pei, J., Tercier-Waeber, M.-L. and Buffle, J. (2000). Simultaneous determination and speciation of zinc, cadmium, lead and copper in natural waters with minimum handling and artefacts by voltammetry on gel-integrated microelectrode arrays, Anal. Chem., 72, 161-171. 

J. J. Rosentreter and R. K. Skogerboe, Trace Determination and Speciation of Cyanide Ion by Atomic Absorption Spectroscopy, Anal. Chem. 1991,63, 682. 

Leonard, K.S., McCubbin, D. and Harvey, B.R. (1993) A radiochemical procedure for the determination and speciation of radio-cobalt in environmental waters. Sci. Total Environ., 130/131, 237-251. 

Advances in selenium biochemistry (Arthur, 1994 Heider and Boeck, 1994 Foster and Sumar, 1997 Patching and Gardiner, 1999) and methods for the determination and speciation of the element in biological and environmental samples (Pyrzynska, 1996 D Ullivo, 1997 Thomson, 1998) have been reviewed. In this section, a brief overview of more recent developments in analytical methods and their application to the study of selenium-containing species in biological materials is provided. 

Ure, A.M. (1990) Trace elements in soil their determination and speciation. Fresenius J. Anal. Chern., 337, 577-581. 

Bums, D.T., M. Harriott, and F. Glockling. 1987. The extraction, determination and speciation of tribu-tyltin in seawater. Fresenius J. Anal. Chem. 327 701-703. 

Gomez V. and M.P. Callao. 2006. Chromium determination and speciation since 2000. Trends Anal. Chem. 25 1006-1015. 

N. P. Vela, D. T. Heitkemper, Total arsenic determination and speciation in infant food products by ion chromatography-inductively coupled plasma-mass spectrometry, J. AOAC Int., 87 (2004), 244 D252. 

Enhancing the Se levels in crops can be achieved by adding organic amendments (manure of Se-supplemented farmed animals) or inorganic Se to mineral fertilizers [116, 117]. The use of sodium selenate-enriched fertilizers in Finland resulted in increased Se levels in different foods and, consequently, the average serum Se in the population improved over the period 1984 D1988. ICP-MS was used to study the feasibility of wheat enrichment by selenate addition to soil fertilizers [118]. AE-HPLC-ICP-MS was optimized for the separation of selenite, selenate, selenocysteine, and selenomethionine. Total Se determination and speciation analysis were performed in water extracts and in enzymatic digests of wheat samples. It was shown that a major part of the selenate taken up by cereals was converted to selenomethionine. 

ICP-MS this is the primary detection technique in the determination and speciation of trace elements. It has excellent selectivity, sensitivity, multielement and isotopic capability and easy coupling with different separation techniques (especially low-flow and low-volume chromatographic methods). Modem instruments enable practically interference-free response over the wide range of element concentrations in a variety of samples and quantification of metalloids and nomnetals. 

Capar, S.G., Szefer, P. Determination and speciation of trace elements in foods. In Otles, S. (ed.) Methods of Analysis of Food Components and Additives, pp. 111-158. CRC Press,... 

Vanhaecke, F., Resano, M., Moens, L. Electrothermal vaporisation ICP-mass spectrometry (ETV-ICP-MS) for the determination and speciation of trace elements in solid samples - a review of real-life applications from the author s lab. Anal. Bioanal. Chem. 375, 188-195 (2002)... 

Both GC and LC behavior of metal complexes of various ligand types including salicy-laldimines and Schiff bases and fluorinated /3-diketones was reported. Metal ions included the lanthanides, transition metals, Pt, Pd and Zn. Dissociation and thermal instabilities were found to be the main limitations in the chromatography of such derivatives. The data indicate that pre-column derivatization and GC is unlikely to provide a viable method for the ultratrace determination of metal ions except in rare circumstances. On the other hand, LC of complexed metal ions was found as a valuable technique that combines the advantages of versatility, specificity and sensitivity with the capacity for simultaneous determination and speciation. Diastereoisomers of oxovanadium(IV) complexes of tetradentate Schiff bases could be resolved by both GC and LC . ... 

Vanhaecke, F. Moens, L. Recent trends in trace element determination and speciation using inductively coupled plasma mass spectrometry. J. Anal. Chem. 1999, 364 (5), 440-451. 

Determination and Speciation of Cu and Zn. Water samples were collected with a sampler (Go-Flo, General Oceanics), which had been carefully cleaned with HN03. Samples were filtered in the laboratory (0.45... 

The spectrophotometric methods for the determination (and speciation) of phosphorus in natural waters have been compared with other analytical techniques [144]. 

Heumann, K. G. Isotope-dilution ICP-MS for trace element determination and speciation from a reference method to a routine method Anal Bioanal Chem 2004, 378, 318-329. 

S.K. Aggarwal, R.L. Fitzgerald and D.A. Herold, Mass spectral studies for the determination and speciation of arsenic by gas chromatography-mass spectrometry (GC-MS). In Proceedings of Eighth ISMAS Symposium on Mass Spectrometry, 7-9 December 1999, Hyderabad, Vol. II, S.K. Aggarwal (Ed.). ISMAS Mumbai, 1999, pp. 553-556. 

Decision making based on the need for in-line analyte concentration in the determination and speciation of iron [392,393]. 

C. Pons, R. Forteza, V. Cerda, The use of anion-exchange disks in an optrode coupled to a multi-syringe flow-injection system for the determination and speciation analysis of iron in natural water samples, Talanta 66 (2005) 210. 

Rosentreter, J.J. Skogerboe, R.K. (1991) Trace determination and speciation of cyanide ion by atomic-absorption spectroscopy. Anal. Chem., 63, 682—688. 

Liu, Y., Lopez-Avila, V., Alcaraz, M., and Beckert, W. F., Offline complexation/SFE and GC with atomic emission detection for the determination and speciation of organotin compounds in soils and sediments. Anal. Chem., 66, 3788-3796, 1994. 

More recently for ultratrace determination and speciation of antimony compounds the so-called hyphenated instrumental techniques have been applied which combine adequate separation devices with suitable element-specific detectors. They include high-performance liquid chromatography (HPLC) connected on-line with heated graphite furnace (HGF) AAS (HPLC-HGF-AAS), hydride-generation atomic fluorescence spectrometry (HPLC-HG-AFS) or inductively coupled plasma (ICP) mass spectrometry (MS) (HPLC-ICP-MS) capillary electrophoresis (CE) connected to inductively coupled plasma mass spectrometry (CE-ICP-MS) and gas chromatography (GC) coupled with the same detectors as with HPLC. Reliable speciation of antimony compounds is still hampered by such problems as extractability of the element, preservation of its species information, and availability of Sb standard compounds (Nash et al. 2000, Krachler etal. 2001). Variants of anodic stripping voltammetry for speciation of antimony have also been applied (Quentel and Eilella 2002). 

Nash et al. (2000) (Methodologies for determination of antimony in terrestrial environmental samples). The review by Tolg (1987) (Extreme trace analysis of the elements -the state of the art today and tomorrow) is an insightful review by an experienced trace analyst concentrating on atomic spec-trometric methods including AAS, OES, XRE, MS with many variants of excitation. A table is provided comparing the capability of determinative methods listing the method, the specific technique, limit of determination, matrix effects, multielement determination, and speciation analysis. Methods compared include AAS, ZAAS, OES-DCP, OES-ICP, OES-MIP, OES-HC, EANES, AES, XRS, MS, NAA, voltammetry, LAS and fluorimetry. 

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