Densitometric determination of catecholamine metabolites and 5-hydroxy-indoleacetic acid after two-dimensional thin-layer chromatography on cellulose

A quantitative two-dimensional chromatographic determination for the catecholamine metabolites vanilglycolic (vanilmandelic) acid, vanilacetic acid, vanillactic acid and vanilglycol is described. The method can also be used for the determination of 5-hydroxy-indoleacetic acid. The analytical procedure consists of the following steps: 1. extraction (after enzymatic hydrolysis when vanilglycol has to be determined); 2. two-dimensional chromatography on thin-layer cellulose; 3. quantitative evaluation of the spots by means of a chromatogram scanner. Standard deviations, recoveries, 24-h excretions in 10 normal adults and results in 10 patient suffering from neurogenic tumors are given. Some of the merits of a multi-component determination of the type described here for the clinical diagnosis of secreting neurogenic and serotonin-producing tumors are discussed