Development and validation of a high-performance liquid chromatography assay for the quantitative determination of 7-oxo-dehydroepiandrosterone-3 beta-sulfate in human plasma

A new, simple, reproducible and reliable high-performance liquid chromatogr aphy method with ultraviolet absorbance detection at 240 nm was developed a nd validated for the determination of 7-oxo-dehydrorpiandrosterone-3 beta-s ulfate in human plasma. The method was based upon solid-phase (C-18) extrac tion of plasma after addition of 17 beta-hydroxy-3 beta-methoxy-androst-5-e n-7-one as internal standard. Using 1 mi of plasma for extraction, the dete ction limit of the assay was 3 ng/ml. The standard curve was linear over th e concentration range 10-1000 ng/ml. Stored at -20 degrees C for about 4 mo nths at various concentrations in plasma, 7-oxo-dehydroepiandrosterone-3 be ta-sulfate did not reveal any appreciable degradation. Also included herein is a method for the simultaneous detection and determination of 7-oxo-dehy droepiandrosterone and 7-oxo-dehydroepiandrostcrone-3 beta-acetate in plasm a. (C) 1999 Elsevier Science B.V. All rights reserved.