Measurement of testosterone with a high-performance liquid chromatograph equipped with a flow-through ultraviolet spectrophotometer

A technique is described for measuring nanogram amounts of testosterone using high-performance liquid chromatography with detection by a flow-through spectrophotometer. The addition of a non-radioisotopic internal standard (4-androsten-11β-ol-3,17-dione) to the biological specimen automatically corrects for testosterone losses due to extraction and non-quantitative sample injection into the high-performance liquid chromatograph. This new method, which can be performed by inexperienced personnel, is shown to be rapid, precise, accurate and specific for testosterone.