Liquid chromatographic methods for chloral hydrate determination

Liquid chromatographic methods, based on reversed-phase (RP) and anion-exch ange mechanisms, have been developed for chloral hydrate determination. Bot h methods are preceeded by derivatization of chloral hydrate. For RP separa tions, different reagents [namely dansylhydrazine and o-(4-nitrobenzyl)hydr oxylamine] have been studied, but the best results have been achieved using 1,2-benzenedithiol with UV detection at 220 nm. The anion-exchange method is based on derivatization with NaOH to form sodium formate that is then an alyzed by anion-exchange, with suppressed conductivity detection. Derivatiz ation conditions were optimized in order to reach the best yield of reactio n. The optimization of the procedure allowed to determine chloral hydrate w ith detection limits as low as 0.2 mug/l with good linearity and reproducib ility. The anion-exchange method was also applied for chloral hydrate deter mination in a drinking water sample. A preconcentration procedure has also been studied. (C) 2001 Elsevier Science B.V. All rights reserved.