Determination of Clavulanic Acid Residue in Edible Tissues of Animals by High Performance Liquid Chromatography-Tandem Mass Spectrometry

【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.