Determination by Thin-Layer Chromatography of Urinary Homovanillic Acid in Normal and Disease States

A rapid method using thin-layer chromatography has been developed to measure urinary HVA (homovanillic acid). Ethyl acetate extracts of urine are chromatographed on glass plates coated with silica gel. The solvent used is the organic phase of benzene: acetic acid: water (2:3:1) mixture. The eluted HVA is treated with Folin's phenol reagent and absorbance is measured at 750 mμ in a spectrophotometer. Normal amounts of HVA in human urine are 8.23 ± 2.96 (mean ± standard deviation) mg/24 hours or 6.42 ± 2.28 mg/g of creatinine. Higher values were obtained in cases of ganglioneuroma and neuroblastoma, in a case of pheochromocytoma, and in one of two cases of hepatolenticular degeneration (Wilson's disease). In three cases of Huntington's chorea, values lay in the normal range.