Residue analysis of spectinomycin in tissues of chicken and swine by HPLC

A reversed-phase HPLC method with ultraviolet detection using p-nitrophenyl hydrazine as a pre-column derivatizing reagent was investigated for the determination of the antibiotic spectinomycin (SPCM) in muscle, liver, kidney and fat of chicken and swine. SPCM was extracted from samples with 10% trichloroacetic acid saturated with EDTA-2Na, and then cleaned up with coupled Sep-Pak Plus PS-2 cartridges. The detection limit of SPCM was 0.02 microgram (potency)/g. Recoveries of SPCM ranged from 77.4 to 97.4% for chicken tissues and from 74.5 to 91.8% for swine tissues. The present method was used for the analysis of chicken tissues after the 11th day of withdrawal (SPCM-medicated drinking water: 500 mg (potency)/L, for 7 days), and swine tissues after the 14th day of withdrawal (SPCM-medicated feed: 100 mg (potency)/kg, for 7 days). Results showed that SPCM concentrations were lower than the MRLs in all tissues.