Abstract: A reversed-phase high performance liquid chromatographic method (RP-HPLC) has been developed for the determination of amoxicillin residue in beeves. Beeves were extracted with phosphate buffer, precipitated the proteins with trichloroacetic acid (TCA) solution, and purified and enriched by solid phase extraction (SPE). The retention results on a C18 column and the chromatography conditions of amoxicillin were investigated. The samples were separated by RP-HPLC and quantified with external standard calibration curves.There are good linear correlations with the correlation coefficient as 0.99934 between the peak areas and concentrations of amoxicillin .The dynamic linear range is 5.0～500μg/ml. The average recoveries of amoxicillin in spiked animal tissues range from 77.3 % to 97.4 %, and the relative standard deviations are between 1.2% and 13.5%. The limit of detection is below 10μg/kg. The relative standard deviations of intra-assay and inter-assay are both within 10%. This analysis method shows good recurrence.

Key words: HPLC, solid phase extraction, amoxicillin, residue, beeves