Study on the fluorescence characteristics of alkaline degradation of cefadroxil, cephradine, cefotaximum sodium and amoxicillini

A simple and sensitive fluorescence method for cefadroxil, cephradine, cefotaximum and amoxicillini is described. The method is based on their degradation under alkaline condition producing fluorescence products. The factors affecting the degradation and the determination were studied in detail. Under optimum conditions a linear relationship was obtained between the concentration of the antibiotics and the fluorescence intensity. The linear ranges of cefadroxil, cephradine, sodium cefotaximum and amoxicillini were 2.5 x 10(-5) similar to 4.0 x 10(-3) mg/ml, 4.0 x 10(-5) similar to 4.0 x 10(-3) mg/ml, 2.0 x 10(-5) similar to 4.0 x 10(-3) mg/ml and 8.0 x 10(-5) similar to 4.0 x 10(-3) mg/ml, respectively. Their detection limits (S/N=2) were 5.0x10(-6) mg/ml, 8.0x10(-6) mg/ml 2.0x10(-6) mg/ml and 7.5x10(-6) mg/ml respectively. The proposed method has been applied to the determination of cephalosporins and amoxicillini in human serum, urine and pharmaceutical formulations with satisfactory results.