2 SELECTIVE SPECTROPHOTOMETRIC METHODS FOR THE DETERMINATION OF AMOXICILLIN AND CEFADROXIL

Two simple, rapid and selective spectrophotometric procedures were dev eloped for the determination of amoxicillin and cefadroxil. The method s are based on the selective oxidation of the drugs with N-bromosuccin imide or N-chlorosuccinimide in an alkaline medium to give an intense yellow product (lambda(max) = 395 nm). The reaction conditions were st udied and optimized. The reactions obey Beer's law over the range 1-20 mu g ml(-1) for the two drugs with the two reagents. Interferences fr om other antibiotics, additives and common degradation products were i nvestigated. The proposed methods were applied to the analysis of phar maceutical formulations containing amoxicillin, either alone or in com bination with potassium clavulanate or flucloxacillin. They were also applied to the analysis of some cefadroxil dosage forms. The results o btained compared favourably with those obtained with other reported me thods.