Comparison of purification procedures for the isolation and detection of anabolic residues in faeces using gas chromatography mass spectrometry

Within several regional field laboratories and the national reference labor atory a harmonised methodology for the analysis of anabolic residues in fae cal samples was developed. The method consists of a Liquid-liquid and a sol id-phase extraction step, followed by a high-performance liquid chromatogra phy purification step. Using gas chromatography-mass spectrometry, currentl y illegally used anabolic steroids can be detected in faeces at the ppb lev el. Within this context acidification, followed by centrifugation under coo ling, allows efficient, practical and rapid defatting of faecal samples. Fu rthermore, a combination of a silica and an aminopropyl solid-phase extract ion column was found to give the best results as regards the sample purific ation process.