Abstract
The Nair and Vaidyanathan modification of the Evans tungstate method has been automated to determine catechols in urine. The automation involves improving the sensitivity of the manual procedure from the grams-per-liter range to the milligrams-per-liter range, removing the turbidity caused by reactions between the reagents and urine, and eliminating the positive error caused by normal urinary recoveries of added catechol in the 0- to 15-mg/liter range average 96.8%, and the standard deviation for replicate analyses is 0.15 mg/liter. The test is specific for substances having a catechol structure (ortho-dihydroxy aromatic materials). It should find application as a screening test to detect abnormally high urinary catechol concentrations resulting from the metabolism of toxins, such as benzene, drugs (aspirin, etc.), food-stuffs or normal biological substances.