Abstract: To develop a high performance liquid chromatography method for determination of 3-methyl-quinoxaline-2-carboxylic acid (MQCA) in porcine liver.MQCA was extracted from porcine liver with 0.3 mol/L hydrochloric acid. The extract was cleaned up on MAX Sep-Pak Silica solid-phase extraction cartridge. Then the eluate was collected and dried under a gentle stream of nitrogen gas and the dissolved residue was analyzed by HPLC. The HPLC separation was performed on a Symmetry Shield reversed phase C18 boned silica column, with mobile phase of acetonitrile-methanol-0.5% formic acid (15∶50∶35,V/V/V) and determination wave of 320 nm in an UV detector.The validation was carried out on spiked porcine liver(spiked at 20～250 μg/kg), and the average recoveries of target drug ranged from 72.35% to 85.00%, with intra-day relative standard deviations(RSD)(n＝5) of 5.56% to 9.49%, and inter-day RSD(n＝3) of 5.96% to 9.63%.The limits of quantification (LOQ) in porcine liver was 20 μg/kg and the limits of detection (LOD) was 6.65 μg/kg.The results demonstrated that the sensitivity, accuracy, and precision of this method meet the requirements of veterinary drug residue analysis. The method is applicable to detect MQCA in porcine liver.

Key words: high performance liquid chromatography（HPLC）; porcine liver; MQCA