Microdetermination of hypoxanthine and xanthine

Abstract

A method based on the use of xanthine oxidase is described which permits the detn. of hypoxanthine and xanthine in quantities from 0.1 mg. upwards. If both O2 uptake and uric acid formation are measured it is possible to distinguish between hypoxanthine and xanthine, since the former requires 2 atoms, the latter 1 atom of O2. In testing the specificity of the method it was found that purine reacts with xanthine oxidase as rapidly as hypoxanthine, but since purine is not found in biological material it is improbable that it will interfere.