Identification of volatile selenium compounds produced in the hydride generation system from organoselenium compounds

We report a novel aqueous derivatization of selenomethionine (Semet), selen oethionine (Seet) and trimethylselenonium ion (TmSe) by NaBH4 and HCl to vo latile selenium species, namely, diethyldiselenide (DeDSe), dimethyldiselen ide (DMDSe), dimethylselenide (DmSe) and ethylhydrogenselenide (ESeH), in t he hydride generation (HG) system. The volatile selenium compounds produced in the HG system were on-line trapped and concentrated in a U-tube that wa s immersed in the liquid nitrogen trap. The trapped volatile Se compounds w ere volatilized at 80 degreesC in a water bath, and 50-500 muL of volatile gas was injected into the GC/AED and GC/MS, respectively. It has been estab lished that DmSe, DmDSe, and DeDSe are the predominant Se compounds that ar e produced in the HG system from TmSe, Semet, and Seet, respectively, follo wed by ESeH from Seet, Analytical methods previously employed have stated t hat these compounds are inactive in the HG system, Prior decomposition of S emet, Seet, and TmSe to selenous acid is essential before HG. To the best o f our knowledge, current findings for the production and identification of volatile selenium compounds in the HG system are new and different from exi sting reports; hence, direct estimation of Semet, Seet, and TmSe is possibl e when coupling with a HG system using a suitable Se-specific detector.