NEW VALIDATED SPECTROFLUORIMETRIC AND SPECTROPHOTOMETRIC METHODS FOR THE DETERMINATION OF CLOPIDOGREL IN PHARMACEUTICAL PREPARATIONS USING EOSIN

New Sensitive and accurate two spectroscopic methods were developed and validated for the determination of Clopidogrel (CLP) in tablet dosage forms. The spectrophotometric method (Method I) is based on the formation of red colored complex with eosin at (545 nm) in sodium acetate – acetic acid buffer of pH 3. The absorbance-concentration plot is rectilinear over the range (0.5-9 µg mL-1) with LOD of (0.076 µg mL-1) and LOQ of (0.23 µg mL-1). The Spectrofluorimetric method (Method II) depends on the quantitative quenching effect of Clopidogrel on the native fluorescence of eosin at the same pH. The quenching effect of the formed ion-pair complex of the drug with eosin was measured at (560 nm) after excitation at (499 nm). The fluorescence-concentration plot is rectilinear over the range (0.2-6 µg mL-1) with LOD of (0.0341 µg mL-1) and LOQ of (0.1033 µg mL-1). Under the optimized experimental conditions, the proposed methods were validated as per International Conference of Harmonization guidelines. The proposed methods were perfectly applied to the analysis of commercial tablets containing the drug. Statistical comparison of the results with those of the reference method illustrate good agreement and confirm that there were no significant difference in the accuracy and precision between the proposed and reference one respectively.