title: Combined high-performance liquid chromatography and radioimmunoassay for the screening of 19-nortestosterone and methyltestosterone residues in meat samples.
abstract: A procedure is described for the detection of 17 beta-19-nortestosterone (17 beta-19-NT) and 17 alpha-methyltestosterone (17 alpha-MT) in muscle tissue by a combination of high-performance liquid chromatography and radioimmunoassay. The steroids were released from the muscle tissue by enzyme digestion, and the extracts were purified by solid-phase extraction. A meat sample from the retail trade, which was proved to contain 17 beta-19-NT and 17 alpha-MT residues by gas chromatography-mass spectrometry, and blank meat samples obtained from non-treated experimental animals were purified and the extracts injected into the liquid chromatograph. With an automatic fraction collector, fifteen fractions of 1 ml each were obtained, which after evaporation were subjected to a radioimmunoassay for the steroid concerned. It was demonstrated that none of the fractions from the blank meat samples contains any substance that interfered with the immunochemical detection system. In addition, a good qualitative agreement between the two sets of results was obtained. Although the sample preparation step is rather labour-intensive, the method can be successfully applied as a reliable confirmation method for positive radioimmunoassay screening results in circumstances where no gas chromatography-mass spectrometry facilities are available.
authors.affiliation: Laboratory of Food Analysis, Faculty of Pharmaceutical Sciences, State University of Ghent, Belgium.
authors.forename: E
authors.initials: E
authors.lastname: Daeseleire
authors.forename: A
authors.initials: A
authors.lastname: De Guesquière
authors.forename: C
authors.initials: C
authors.lastname: Van Peteghem
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D008460:Meat / Q000032:analysis*; D008777:Methyltestosterone / Q000032:analysis*; D009277:Nandrolone / Q000032:analysis*; D011863:Radioimmunoassay / Q000379:methods*
chemical_list: D009277:Nandrolone; D008777:Methyltestosterone