Improved procedure for n-hexyl chloroformate-mediated derivatization of highly hydrophilic substances directly in water:hydroxyaminic compounds

A fast derivatization procedure, carried out directly on aqueous solutions of highly hydrophilic substances, has been modified and improved in order to determine amino alcohols, hydroxylamines, aminophenols and other aminic substances in water. Aqueous samples were mixed with n-hexyl chloroformate under sonication and subsequently added to the catalyst, a saturated pyridine solution of dicyclohexylcarbodiimide. The n-hexane extracts were analyzed by GC-MS in the positive chemical ionization mode. Detection limits on the non-concentrated extracts (1:1, v/v vs. the sample) were in the 10-100 mu g/l range, depending on the analyte. (C) 1998 Elsevier Science B.V.