Screening of chloramphenicol residues in pork muscle by planar chromatography

A rapid planar chromatographic method is described for the qualitative determination of chloramphenicol residues in muscle. The drug is extracted with ethyl acetate and purified by solid-phase extraction. After elution, the collected phase is evaporated to dryness. The residue is dissolved in methanol, spotted on a silica gel plate, and chromatographed. After elution, the chloramphenicol is visualized after reduction with fluorescamine. This method detects chloramphenicol in meat at 10 micrograms/kg and has a sample throughput of about 25 samples per analyst per day.