On line speciation of Se(VI), Se(IV), and trimethylselenium by HPLC-microwave oven-hydride generation-atomic absorption spectrometry

• Published in: Fresenius' Journal of Analytical Chemistry 1995-01, Vol.351 (4-5), p.438-442
• Main Authors: COBO-FERNANDEZ, M. G, PALACIOS, M. A, CHAKRABORTI, D, QUEVAUVILLER, P, CAMARA, C
• Format: Article
• Language: English
• Subjects: Analytical chemistry; Chemistry; Chromatographic methods and physical methods associated with chromatography; Exact sciences and technology; Other chromatographic methods
• ISSN: 0937-0633; 1432-1130; 1618-2650
• DOI: 10.1007/bf00322915

An on-line system is proposed consisting of an anion-exchange chromatographic column, microwave-induced thermooxidation of trimethylselenium in the presence of persulphate, and microwave-induced thermoreduction of Se(VI) to Se(IV) in HCl medium, followed by hydride generation and atomic absorption for the determination of trimethylselenium (TMeSe), Se(IV) and Se(VI). Trimethylselenium is eluted in the dead volume of an anion-exchange column (Hamilton PRP-X-100), before elution of Se(IV) and Se(VI). Optimum chromatographic conditions have been obtained using 100 mmol L super(-1) phosphate buffer (pH = 6.8) H sub(2)PO sub(4) super(-)/HPO sub(4) super(2-) as the mobile phase. Recoveries were around 100%, absolute detection limits were 1.1, 1.4 and 2.2 ng for TMeSe, Se(IV) and Se(VI), respectively. Precision was lower than 10% in all cases. The method has been applied to tap water.