DETERMINATION OF QUINOXALINE CARBOXYLIC-ACID (METABOLITE OF CARBADOX)IN ANIMAL TISSUE BY HPLC

A method for the determination of residues of quinoxaline-2-carboxylic acid (QCA), the major metabolite of carbadox, in pig kidney has been developed. Tissue samples were subjected to alkaline hydrolysis, liqui d-liquid extractions, ion-exchange chromatography and further extracti on to concentrate the analyte and purify the extract. Determination wa s by reverse phase HPLC with UV detection at 320 nm. Validation exerci ses carried out on batches of six samples fortified with 0.050 mg/kg Q CA on three separate days gave mean recoveries ranging from 72 to 79% with relative standard deviations ranging from 5.6 to 7.8%. Samples fo rtified with 0.010 mg/kg QCA gave a mean recovery of 100% with a relat ive standard deviation of 9.8%.