Application of Dual Wavelength Spectrophotometric Method for Quantification of Amlodipine Besylate and Celecoxib in their Combined Dosage Form
Objectives: The present study focused on application of a simple, sensitive, rapid, accurate and precise, dual wavelength spectrophotometric method for the quantification of amlodipine besylate and celecoxib in combined dosage form using methanol as a solvent. Materials and Methods: Based on overlain spectra, for quantification of both drugs by proposed dual wavelength spectrophotometric method, the wavelengths selected for the analysis are 280 nm (λ1), 290 nm (λ2), 340 nm (λ3) and 360 nm (λ4). For the quantification of amlodipine besylate absorbance difference measurements was carried out at 340 nm and 360 nm where celecoxib shows same absorbance value. In case of celecoxib absorbance difference measurement carried out at 280 nm and 290 nm where amlodipine besylate showed the same absorbance value at both the wavelengths. The proposed was validated in accordance with guidelines of ICH. Results: The method shown linearity in the concentration range 20-100 μg/ml and 5-25 μg/ml for celecoxib and amlodipine besylate respectively, with good correlation coefficient (r2>0.998). The percentage recovery at different concentration levels were found to be 98.33 to 99.75 % for amlodipine besylate and 98.58 to 99.303 % for celecoxib, indicating the accuracy of the method. Conclusion: The results of analysis were statistically validated and demonstrated to be free from interferences through recovery studies. For the quantification of both the drugs in the commercial available tablets the method was successfully applied.