THE DETERMINATION OF 17-OH CORTICOSTEROIDS IN URINE

Abstract

Two methods that are widely used for the routine determination of 17-hydroxy-corticosteroids in urine were originally described by Reddy, Jenkins & Thorn (1952) and Norymberski, Stubbs & West (1953). They both avoid the problem of the hydrolysis of conjugated corticosteroids, a factor which complicated the earlier methods of analysis. In the first method the free and conjugated 17-hydroxycorticosteroids are extracted from acidified urine by n-butanol and then estimated by reaction with phenylhydrazine (Porter & Silber, 1950). The second method involves the oxidation of the 17-hydroxycorticosteroids with sodium bismuthate to 17-ketosteroids (17-KS) which are then hydrolysed and measured by the Zimmermann reaction. There have been numerous criticisms and modifications of these methods. The major difficulty associated with the method of Reddy et al. (1952) has concerned the colour reaction. The 62 % v/v H₂SO₄ used in the phenylhydrazine reagent often produces as much colour with the extracts of urine