TRACE ANALYSIS OF CHLORAMPHENICOL RESIDUES IN EGG POWDERS BY CAPILLARY GAS-CHROMATOGRAPHY ELECTRON-CAPTURE DETECTION

Chloramphenicol (CAP) in egg powder samples was extracted with acetonitrile by sonication. After centrifugation, the supernatant was diluted with water and de fatted with n-hexane, and cleanup was performed on a column of graphitized carbon black (GCB). Different silylation methods were compared for the derivatization of the analytes. Trimethylsilyl N, N-dimethylcerbamate produced stable di-TMS derivatives which were analyzed by capillary gas chromatography-electron capture detection (CGC-ECD) after splitless Injection. The meta isomer of the ehloramphenicol served as the internal standard for quantitation, and 80%+ mean recovery was obtained in the 0.1-10 μg/kg (ppb) concentration range. © 1990 Oxford University Press.