THE DETERMINATION OF NANDROLONE AND ITS METABOLITES IN URINE BY GAS-CHROMATOGRAPHY MASS-SPECTROMETRY

The determination of nandrolone and its major metabolites in urine of a healthy volunteer is typically performed by fused-silica capillary c olumn gas chromatography with electron impact quadropole mass spectrom etry. Two well-known urinary metabolites of nandrolone, 19-norandroste rone and 19-norethiocholanolone, were isolated by XAD-2 adsorption fro m urine, eluted with methanol and separated into unconjugated and conj ugated fractions. The conjugated fraction was hydrolyzed with beta-glu curonidase from Escherichia coli and the samples derivatized with MSTF A/ammonium iodide/dithioerythritol. Ion fragmentograms of the bis-trim ethylsilyl derivatives of nandrolone and its metabolites displayed mol ecular ions of M+ = 420 and M+-15 = 405. Extraction yield and the mini mum detection limit of nandrolone in urine were identified. Finally, e xcretion rates of nandrolone and its metabolites in urine were determi ned.