Estimation of Testosterone in Human Peripheral Blood Using S35-thiosemicarbazide1

Abstract

A double isotope method for the estimation of testosterone in 10 ml human peripheral plasma is described. S³⁵-thiosemicarbazide (100 mc/mM) is used as reagent and 1,2-H³-testosterone (137 μc/μc) as indicator. Purification is obtained by 2 silica gel thin layer and 1 paper chromatogram of the thiosemicarbazone of testosterone followed by 1 thin layer and 1 paper chromatogram of the 2,4-diacetylthiosemicarbazone of testosterone acetate.⁴ The precision and accuracy of the method is 6% for quantities of testosterone occurring in male plasma. The nonspecific blank is 0.013±0.004 (SD) μg/100 ml (plasma from ovariectomized-adrenalectomized women). No known product or metabolites of endocrine glands were found to be likely to interfere with the specificity of the estimation, with the possible exception of 17-epitestosterone (5% of any initial amount of this compound would be estimated as estosterone). A highly significantly greater value was found for testosterone in the plasma of 8 ovariectomized women [(0.032±0.003 (se) μg/100 ml] compared with 5 ovariectomized-adrenalectomized women [0.013±0.002 (se) μg/100 ml]. Eleven normal men (ages 21–36) had a mean plasma concentration of 0.80±0.25 (SD) μg/100 ml and 2 normal women 0.059 and 0.079 μg/100 ml in the progestational phase of the menstrual cycle.