Liquid chromatographic analysis of monosaccharides with phenylisocyanate derivatization

Because of the lack of sensitivity in carbohydrate analysis, HPLC pre-column derivatization techniques which give strongly UV absorbing compounds have been reported. These techniques have the disadvantage of leading to several chromatographic peaks from each reducing sugar. To enhance both the sensitivity and the selectivity of such specific separation problems, a simplex procedure was applied to optimize the phenylisocyanate derivatization of monosaccharides: a major and stable derivative was formed under the optimal conditions established. The method was extended to deoxysugars and methylglycosides. The limit of detection was 0.2-1 ng for all sugars tested.