Abstract: 【Objective】A confirmatory method was developed for the determination of clavulanic acid (CLAV) residue in edible tissues of animals by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). 【Method】 One gram tissues were extracted by 3 mL 0.01 mol•L-1 ammonium acetate solution and 3 mL acetonitrile，a back-extraction of the acetonitrile with dichloromethane，aqueous layer was diluted to 4mL，and the sample was determined by HPLC-MS/MS after defatted with N-hexane. The chromatographic separation was achieved on a Luna 5μ C8 column using 0.1% formic acid in water and acetonitrile as mobile phases with gradient elution. The identification of CLAV was carried out by MS/MS equipped with electrospray ionization in negative scanning and multiple reaction monitoring (MRM) modes. 【Result】Matrix-matched calibration standard was used for the quantification. Good linearity was achieved with correlation coefficients more than 0.999 for all analytes in the concentration of 5-500 μg•L-1. The limit of detection (LOD，S/N≥3) was 10 μg•kg-1 in tissues, and the limit of quantification (LOQ，S/N≥10) was 20 μg•kg-1. The mean recoveries at the four spiked levels of LOQ, 1/2MRL (the maximum residue limit), MRL and 2MRL were in the range of 76.39%-89.26% , with the inter-day relative standard deviations (RSD) of 1.89%-6.20%. 【Conclusion】In conclusion, the established method can be applied for the determination of CLAV residues in edible tissues of animals.

Key words: high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) , clavulanic acid , edible tissues , residue