CONCEPTS FOR THE IDENTIFICATION AND DETERMINATION OF SELENIUM-COMPOUNDS IN THE AQUATIC ENVIRONMENT

Organic selenium compounds play an important role in the global cyclin g of selenium. Only few methods exist for the determination of organic selenium compounds. High-performance liquid chromatography (HPLC) in combination with selenium-specific detection might be an appropriate m ethod for the determination of these compounds. Three selenium-specifi c devices (FAAS, GFAAS, ICP-MS) are evaluated as chromatographic detec tors. The HPLC/FAAS system has absolute detection limits of 10 ng Se w ith linear calibration curves from 10 to 100 mg Se/l (100 mu l injecti on). HPLC/GFAAS has lower detection limits (1 ng Se) and linear calibr ation curves from 0.2 to 5 mg Se/l (100 mu l injection). HPLC/ICP-MS s hows the lowest absolute detection limits (0.1 ng Se) and the greatest linear calibration range (10 mu g to 10 mg Se/l for 100 mu l injectio n) of the investigated systems. The advantages, disadvantages, and pos sible applications for these hyphenated techniques are discussed. Dire ctions of future research are proposed.