A rapid method for the assay of lactulose

Abstract

A simple and rapid method of determining lactulose in the presence of the other carbohydrates has been described. The method is based on the cysteine-carbazole-sulfuric acid reaction of lactulose separated from the other carbohydrates by thin-layer chromatography. The method makes it possible to determine lactulose in amounts from 5 to 100 μg contained in 1 ml of the eluate from the developing spot. Aldoses and ketoses which usually occur do not influence the result. © 1965.