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

Organic selenium compounds play an important role in the global cycling 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 method for the determination of these compounds. Three selenium-specific devices (FAAS, GFAAS, ICP-MS) are evaluated as chromatographic detectors. The HPLC/FAAS system has absolute detection limits of 10 ng Se with linear calibration curves from 10 to 100 mg Se/l (100 mu l injection). HPLC/GFAAS has lower detection limits (1 ng Se) and linear calibration curves from 0.2 to 5 mg Se/l (100 mu l injection). HPLC/ICP-MS shows 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 injection) of the investigated systems. The advantages, disadvantages, and possible applications for these hyphenated techniques are discussed. Directions of future research are proposed.