An Enzymatic Spectrophotometric Method for the Determination of Xanthine and Hypoxanthine

Abstract A method for determining the total content of the oxypurines xanthine and hypoxanthine in urine is described which is technically simplified and has greater specificity than existing methods. This method is highly specific, reproducible, and accurate. It also allows an estimation of the present xanthine and hypoxanthine in the urine without performing any additional measurements. When applied to plasma, special concentrating procedures are required and the method is therefore less precise.