DEVELOPMENT AND VALIDATION OF SPECTROPHOTOMETRIC DETERMINATION OF CEFPODOXIME PROXETIL IN PURE AND TABLET DOSAGE FORMS THROUGH ION-PAIR COMPLEX FORMATION USING BROMOTHYMOL BLUE

摘要

Objective: A simple, direct and accurate spectrophotometric method has been developed for the determination of cefpodoxime proxetil (CEFP) in pure and pharmaceutical formulations by complex formation with bromothymol blue (BTB). Methods: The method involves the formation of yellow ion-pair complexes between BTB reagent and CEFP in chloroform. The two formed complexes ([CEFP]: [BTB] and [CEFP]: [BTB] 2 ) have maximum absorption at l max 422 nm. The proposed method was validated for specificity, linearity, precision and accuracy, repeatability, sensitivity (LOD and LOQ) and robustness with an average recovery of 99.0-101.4%. Results: The formed complex ([CEFP]: [BTB] 2 ) was measured against the reagent blank prepared in the same manner. Variables were studied in order to optimize the reaction conditions. Molar absorptivity (e) for two complexes were 8100 and 12600 L. mol -1 . cm -1 , respectively. Beer’s law was obeyed in the concentration range of 0.5576-55.760 μg/ml in the present of 1x10 -3 mol/l of BTB with good correlation coefficient (R 2 = 0.9995). The relative standard deviation did not exceed 4.7%. The limit of detection (LOD) and the limit of quantification (LOQ) were 0.088 and 0.27 μg/ml, respectively. Conclusion: The developed method is applicable for the determination of CEFP in pure and different dosage forms with the average assay of marketed formulations 99.5 to 103.2%, and the results are in good agreement with those obtained by the RP-HPLC reference method.