Chromatographic Investigation of Purines in Normal Human Urine.

Abstract

The purine constituents other than uric acid and the methyluric acids were investigated in 2 normal subjects. The new method involved passage of acidified urine through a column of Dowex 50, washing with water to remove uric acid, and elution with ammonia. Purines precipitated in the eluate by acid AgNO3 were separated by paper chromatography and examined spectrophotometrically. On a meat-free, low-purine diet, each subject excreted daily approximately 10 mg hypoxanthine, 4 mg xanthine, 1.4 mg adenine, 0.4 mg guanine, 4.5 mg 7-methylguanine, 0.5 mg 1-methylguanine, and 5 UV-absorbing substances not yet identified. Paraxanthine, 1-methylxanthine and 7-methylxanthine were also excreted when caffeine was ingested.