A METHOD FOR THE ESTIMATION OF INDIVIDUAL URINARY CORTICOSTEROIDS, PREGNANEDIOL, PREGNANETRIOL AND PREGNANETRIOLONE FOLLOWING THEIR SEPARATION BY THIN-LAYER CHROMATOGRAPHY

Abstract

A method is described for estimating urinary pregnanediol, pregnanetriol, pregnanetriolone and the following individual corticosteroids: tetrahydrocortisol (THF), allotetrahydrocortisol (allo-THF), tetrahydrocortisone (THE), cortisol (F), tetrahydro-11-deoxycortisol (THS), tetrahydrocorticosterone (THB), allotetrahydrocorticosterone (allo-THB), tetrahydro-11-dehydrocorticosterone (THA), tetrahydro-11-deoxycorticosterone (THDOC). The main steps of the method are: enzymatic hydrolysis, extraction, fractionation by thin-layer chromatography, and colorimetric estimation using the sulphuric acid reaction for pregnanediol, pregnanetriol and pregnanetriolone, and the blue tetrazolium reaction for the individual corticosteroids. The reliability criteria (specificity, accuracy, precision and sensitivity) of the method have been assessed. The advantage of the method lies in its practicability since, unlike other methods: a) the same urine sample (50 ml) is submitted, for the estimation of the twelve C₂₁ steroids, to the same procedure until fractionation, and b) thin-layer chromatography alone is used for the latter purpose.