Monitoring and identification of residues of anabolic preparations in slaughtered cattle by HPLC with diode array detection.

The new combination of isocratic high performance liquid chromatography (HPLC) with on line UV spectrum detection via a diode array configuration has been applied to the detection and identification of anabolics present in application sites of cattle. Combination of the characteristic retention time in the HPLC chromatogram and a comparison of the full spectrum between 190-400 nm of the anabolic components with that of a standard resulted in a very reliable identification. By means of this method 117 samples of application sites were investigated for the presence of anabolic residues. Of the xenobiotic anabolics , 19-nortestosterone (NT) was found most frequently (in 96 cases), whereas diethylstilbestrol (DES) was found in only 11 cases. In all samples the identification of NT and DES was confirmed by high resolution gas chromatography-mass spectrometry (GCMS).