A COMPARATIVE-STUDY OF LC METHODS FOR ANALYSIS OF CEFRADINE

A comparative study of two isocratic liquid chromatographic methods fo r the analysis of cefradine is described. The first method is prescrib ed by the European Pharmacopoeia for the assay of cefradine, using cla ssical alkyl bonded phase (C18) as the stationary phase. Poor reproduc ibility of the selectivity towards cefradine and its related substance s was observed when this method was used and none of the C18 columns e xamined was able to separate cefradine completely from its potential r elated substances under the prescribed LC conditions. On the other han d, the second method, which uses poly(styrene-divinylbenzene) as the s tationary phase, shows good selectivity even when using columns from d ifferent manufacturers and of different age. Four bulk samples of cefr adine were analysed following both methods and the results were compar ed.