Derivatization and Spectrophotometric Quantification of Pamidronate in Bulk and Dosage Forms

Abstract

Aims: To quantify pamidronate in a sensitive and accurate way either in bulk or dosage forms. Methodology: The quantification of this group of drugs is a challenging task as they lack the presence of chromophore groups in their structure. The proposed method depends on the derivatization of the studied drug by its reaction with 4-Chloro-7-nitro-2,1,3-benzoxazole and the product is measured spectrophotometrically at 470 nm. The conditions for the reaction are optimized regarding the volume of the reagent, the optimum pH for the reaction completion, the buffer volume, the optimum temperature for the reaction and the optimum heating time. Results: The studied drug can be determined in the range of 9-30 µg/mL after optimizing the reaction conditions. Method validation is performed according to ICH guidelines and different validation parameters like, linearity, accuracy, precision and robustness are calculated and found to be excellent. Conclusion: The proposed method is accurate, sensitive and can be applied for the routine analysis of pamidronate in quality control laboratories.