Specific determination of testosterone in female plasma by radioimmunoassay: a rapid and reliable procedure for the routine clinical laboratory.

A rapid and reliable procedure for the specific determination of testosterone in female plasma is described. The assay entails a simple biphasic solvent partitioning of plasma extracts in order to remove cross-reacting steroids before quantitation of testosterone by radioimmunoassay using an antiserum raised against testosterone-11alpha-hemisuccinyl-bovine serum albumin. "Testosterone' values obtained in this way are in excellent agreeement with those obtained following thin-layer chromatographic purification of plasma extracts. However, the present procedure is easier, faster and cheaper to perform, and enables a single technician to assay 32 females plasma samples (in duplicate) in one working day.