Chromatography speciation analysis

C.B. Hymer and J.A. Caruso, Arsenic and its speciation analysis using high-performance liquid chromatography and inductively coupled plasma mass spectrometry. J. Chromatogr.A 1045 (2004) 1-14. 

The compounds MMA, DMA, and TMAO are reduced in acidic aqueous media by borohydride solutions to methylarsine (MeAsH2, bp 2°C), dimethylarsine (Me2AsH, bp 35°C), and trimethylarsine (Me3As, bp 55°C), respectively. These products are useful derivatives for speciation analysis of arsenic because they are readily separated from complex sample matrices and may be further separated from each other by distillation (41) or by gas chromatography (42) prior to their determination by element-specific detectors. Consequently, arsine generation techniques are the most commonly used methods for determining MMA, DMA, and TMAO in marine samples. 

Importantly, neither arsenobetaine nor arsenocholine forms an arsine on treatment with borohydride solutions. Consequently, arsenobetaine and arsenocholine may remain undetected in samples, seawater for example, when arsines are generated and determined in an arsenic speciation analysis. The technique HPLC/ICP-MS is most suitable for the analysis of these (non-arsine-forming) compounds (49). Use of the highly sensitive ICP-MS detector allows application of small quantities of material to the chromatography column, thereby obviating possible sample matrix effects previously observed for arsenobetaine (50). 

Sadi, . . M., Vonderheide, A. P., Becker, J. S. and Caruso, J., Multiple Detection Size-Exclusion Chromatography, ACS Symposium Series 893, American Chemical Society, Washington, DC, 168 (2004). Szpunar, J. and Lobinski, R., Hyphenated Techniques in Speciation Analysis. R. M. Smith (ed.) RSC Chromatic Monographs, Cambridge (2003). 

J. Gomez-Ariza, M.-A. Caro-de-la-Torre, I. Giraldez and E. Morales, Speciation analysis of selenium compounds in yeasts using pressurized liquid extraction and liquid chromatography-microwave-assisted digestion-hydride generation-atomic fluorescence spectrometry. Anal. Chim. Acta, 524(1-2), 2004, 305-314. 

Every coupling application favors one part of the coupling system. A dominating chromatography part leads to the speciation analysis [5,6,26,27]. The elemental specific detection facilities of atomic spectrometry are strongly favored over the multielement capabilities. An inversion of this construction leads to multielement trace analysis in complex matrices with the use of chromatographic equipment as powerful preconcentration and matrix elimination tool [13k The ability of chromatography for a further time resolution between the separated traces is not really required because of the excellent elemental specific detection capabilities of atomic spectrometry. 

Lobinski, R., Boutron, C.F., Candelone, J.P., Hong, S.M., Szpunarlobinska, J. and Adams, F.C. (1993) Speciation analysis of organolead compounds in Greenland snow at the femtogram-per-gram level by capillary gas chromatography/atomic emission spectrometry. Anal. Chem., 65, 2509-2515. 

Pereiro, I.R., Schmitt, V.O. and Lobinski, R. (1997) Elemental speciation analysis by multi capillary gas chromatography with microwave-induced plasma atomic spectrometric detection. Anal. Client., 122, 1057-1061. 

Szpunar, J., Ceulemans, M., Schmitt, VO., Adams, F.C. and Lobinski, R. (1996) Microwave-accelerated speciation analysis for butyltin compounds in sediments and biomaterials by large volume injection capillary gas chromatography quartz furnace atomic absorption spectrometry. Anal. Chim. Acta, 332, 225-232. 

Basic techniques for speciation analysis are typically composed of a succession of analytical steps, e.g. extraction either with organic solvents (e.g. toluene, dichloromethane) or different acids (e.g. acetic or hydrochloric acid), derivatisa-tion procedures (e.g. hydride generation, Grignard reactions), separation (gas chromatography (GC) or high-performance liquid chromatography (HPLC)), and detection by a wide variety of methods, e.g. atomic absorption spectrometry (AAS), mass spectrometry (MS), flame photometric detection (FPD), electron capture detection (ECD), etc. Each of these steps includes specific sources of error which have to be evaluated. 

Lobinski, R. and Adams, F.C. (1992b) Ultratrace speciation analysis oforganolead in water by gas chromatography-atomic emission spectrometry after in-line preconcentration. J. Anal. At. Spectrom., 7, 987-991. 

Qiang, T., W. Johnson, and B. Buckley. 2003. Mercury speciation analysis in soil samples by ion chromatography, post-column cold vapor generation and inductively coupled plasma mass spectrometry. J. Anal. At. Spectrom. 18 696-701. 

Jitaru, P. and F.C. Adams. 2004. Speciation analysis of mercury by solid-phase microextraction and multicapillary gas chromatography hyphenated to inductively coupled plasma-time-of-flight-mass spectrometry. J. Chromatogr. A 1055 197-207. 

Pantsar-Kallio, M. and P.K.G. Manninen. 1999. Optimizing ion chromatography-inductively coupled plasma mass spectrometry for speciation analysis of arsenic, chromium and bromine in water samples. Int. J. Environ. Anal. Chem. 75 43-55. 

Gonzalez-Toledo, E., R. Compano, M. Granados, et al. 2003. Detection techniques in speciation analysis of organotin compounds by liquid chromatography. Trends Anal. Chem. 22 26-33. 

Rosenberg, E., V. Kmetov, and M. Grasserbauer. 2000. Investigating the potential of high-performance liquid chromatography with atmospheric pressure chemical ionization-mass spectrometry as an alternative method for the speciation analysis of organotin compounds. Fresenius J. Anal. Chem. 366 400-407. 

Jiang, G. B., M. Ceulemans, and F.C. Adams. 1996. Optimization study for the speciation analysis of organotin and organogermanium compounds by on-column capillary gas chromatography with flame photometric detection using quartz surface-induced luminescence. J. Chromatogr. A 727 119-129. 

C. Gerbersmann, M. Heisterkamp, F. C. Adams, J. A. C. Broekaert, Two methods for the speciation analysis of mercury in t>sh involving microwave-assisted digestion and gas chromatography-atomic emission spectrometry, Anal. Chim. Acta, 350 (1997), 273 D285. 

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