11-Oxygenated androgens (11-OAs) are being discussed as potential biomarkers in diagnosis and therapy control of disorders with androgen excess such as congenital adrenal hyperplasia and polycystic ovary syndrome. However, quantification of 11-OAs by liquid chromatography-tandem mass spectrometry (LC-MS/MS) still relies on extensive sample preparation including liquid-liquid extraction, derivatization and partial long runtimes, which is unsuitable for high-throughput analysis under routine laboratory settings. For the first time, an established online-solid-phase extraction-LC-MS/MS (online-SPE-LC-MS/MS) method for the quantitation of seven serum steroids in daily routine use was extended and validated to include 11-ketoandrostenedione, 11-ketotestosterone, 11β-hydroxyandrostenedione and 11β-hydroxytestosterone. Combining a simple protein precipitation step with fast chromatographic separation and ammonium fluoride-modified ionization resulted in a high-throughput method (6.6 min run time) featuring lower limits of quantification well below endogenous ranges (63-320 pmol/L) with recoveries between 85% and 117% (CVs ≤ 15%). Furthermore, the ability of this method to distinguish between adrenal and gonadal androgens was shown by comparing 11-OAs in patients with hyperandrogenemia to healthy controls. Due to the single shot multiplex design of the method, potential clinically relevant ratios of 11-OAs and corresponding androgens were readily available. The fully validated method covering endogenous concentration levels is ready to investigate the diagnostic values of 11-OAs in prospective studies and clinical applications.
Keywords: 11-oxygenated androgens; LC-MS/MS; androgens; method validation; steroid hormones.