Analytical methods for quantitative and qualitative analysis of naltrexone and metabolites in biological fluids

Analytical procedures for the determination of naltrexone and metabolites have been presented. The basic procedure involves the use of radiolabeled drugs and thin layer chromatography. Naltrexone, 6 beta-naltrexol and 2-hydroxy-3-O-methyl-6 beta-naltrexol were found by both the TLC procedure and combined gas chromatography-mass spectrometry. The presence of 3-O-methyl-6 beta-naltrexol was indicated by the TLC method, but this metabolite could not be found by mass spectrometry.