DETERMINATION OF CARBONYL-COMPOUNDS IN THE LOW PPB-RANGE BY CAPILLARYELECTROPHORESIS

A new method for analysing carbonyls (aldehydes and ketones) by capill ary electrophoresis (CE) is described. The carbonyls are derivatized w ith DNSH [5-(dimethylamino)naphthalene-1-sulphonehydrazide, Dansylhydr azine] to form detectable compounds and also to form negative charged molecules (buffer pH 7.1). Detection is carried out by UV or, alternat ively, by fluorescence. Eight carbonyls are separated in less than 8 m in. Electrokinetic injection is made by using a new experimental set-u p. The electroendosmatic flow (EOF) is reversed during sample injectio n by pressure. Results are compared with HPLC-analysis as the most com mon method in carbonyl analysis.