C.B. Sekharan's research while affiliated with University of Dar es Salaam and other places

Two simple and sensitive visible spectrophotometric methods (A and B) were developed for the determination of alogliptin in bulk and in its tablet dosage forms. The methods use the reaction of alogliptin with picric acid (method A) or 2,4 dinitrophenol (method B) in the chloroform medium. The complex of alogliptin with picric acid (method A) or 2,4 dinitrophenol (method B) showed λmax at 415 nm and 430 nm respectively. The different conditions affecting the formation and stability of the complexes were optimized. The methods were validated statistically according to ICH. The calibration curve is linear over the concentration range of 10–60 μg ml⁻¹ and 10–50 μg ml⁻¹ for methods A and B, respectively. The proposed methods were successfully applied for the assay of alogliptin in tablets with good recoveries. Interference was not observed from common tablet excipients.

Two simple and sensitive visible spectrophotometric methods (A and B) have been developed and validated for the determination of alogliptin in bulk and tablet dosage forms. The methods are based on the bromination of alogliptin using bromine produced by the action of HCl on the bromate–bromide mixture. The residual bromine is determined with a fixed amount of either methyl orange and measuring the absorbance at 505 nm (method A) or methylene blue and measuring the absorbance at 720 nm (method B). Linearity, accuracy and precision were found to be acceptable over the concentration ranges of 1–10 μg mL⁻¹ and 2.5–12.5 μg mL⁻¹ for method A and method B, respectively. The detection limits were 0.115 μg mL⁻¹ and 0.210 μg mL⁻¹ for method A and method B, respectively. The accuracy of the proposed methods was assessed by recovery studies and the percent recoveries of aloglitpin were found to be 99.91 ± 0.126%–99.99 ± 0.168% for method A and 99.86 ± 0.170%–99.98 ± 0.193% for method B. The methods were successfully applied to the determination of alogliptin in tablets with percentage recovery of 99.84 ± 0.139%–100.20 ± 0.625% (method A) and 99.96 ± 0.351%–10.320 ± 0.422% (method B). The optimized methods were fully validated and proved to be specific, robust, precise and accurate for the quality control of the alogliptin in their pharmaceutical formulations.