Spectrophotometric Determination of Clopidogrel in Pharmaceutical Formulations

Two simple extractive spectrophotometric methods are described for the determination of clopidogrel in pure and pharmaceutical formulations. The method A is based on the formation of ion association complex of the clopidogrel with orange-G in acidic buffer followed by extraction into chloroform. Method B is based on the formation of colored complex in co-ordination of secondary/ tertiary amine group of drug with cobalt thiocyanate in acidic buffer of pH 2.0 which is extractable in to nitrobenzene. The absorbance of organic layer for each method was measured at appropriate λmax against reagent blank. Both the methods obeyed Beer's linearity in the concentration range 50-250 μg/mL for method A and 100-500 μg/mL for method B. These methods were successfully employed for the determination of clopidogrel in pharmaceutical preparations. These methods have been statistically evaluated and are found to be precise and accurate.