A quantitative HPLC-MS method for the simultaneous determination of testosterone, 11-ketotestosterone and 11-beta hydroxyandrostenedione in fish serum.

A simple and novel HPLC-MS method for the simultaneous quantification of testosterone, 11-ketotestosterone, and 11beta-hydroxyandrostenedione in fish serum was developed and validated. Separation was achieved on a C-18 column using a water-acetonitrile mobile-phase with a cycle time of 12 min. Ion detection was performed using ESI positive SIM at [M+H] (m/z 303, 303, 289). The linear ranges (0.2-50 ng/ml), limits of detection (0.1-0.2 ng/ml) and quantification (0.2-0.5 ng/ml) were established. The method was validated by measuring the three androgens in goldfish sera, displaying comparable values to those reported by other analytical techniques (RIA, EIA).