DETERMINATION OF FORMALDEHYDE BY CAPILLARY ELECTROPHORESIS IN THE PRESENCE OF A DIHYDROXYACETONE MATRIX

A capillary electrophoretic (CE) method was developed that allows the trace determination of formaldehyde in the presence of an excess of di hydroxyacetone (DHA). As formaldehyde is an uncharged molecule with no electrophoretic mobility and a low response in UV detection, the cond itions for a direct CE trace determination are not promising. After de rivatisation with dansylhydrazine, a charged formaldehyde dansylhydraz one was obtained which has a very good UV response at 214 nm. Owing to the high separation efficiency of CE, it was possible to separate and determine formaldehyde dansylhydrazone in the presence of a 100 000-f old excess of DHA dansylhydrzone.