AUTOMATED COLUMN LIQUID-CHROMATOGRAPHIC DETERMINATION OF AMOXICILLIN AND CEFADROXIL IN BOVINE SERUM AND MUSCLE-TISSUE USING ONLINE DIALYSIS FOR SAMPLE PREPARATION

A fully automated method is described for the determination of amoxicillin and cefadroxil in bovine serum and muscle tissue. The method is based on the on-line combination of dialysis and solid-phase extraction for sample preparation, and column liquid chromatography with ultraviolet detection. In order to enhance the UV detectability of the analytes, post-column addition of 0.1 M sodium hydroxide is performed. The method shows good linearity and repeatability for both analytes in serum as well as in muscle tissue; the limits of detection in these samples are 0.05 mu g/ml and 0.2 mu g/g, respectively. The method has a sample throughput of 30 samples per 24 h.