Validated Spectrophotometric method for the estimation of Zolpidem tartrate in Bulk and Tablet Formulation

Three simple, precise and economical UV spectrophotometric methods have been developed for the estimation of Zolpidem tartrate in bulk and tablet formulations. Zolpidem tartrate has absorbance maxima at 293 nm in zero order spectrum method (Method A ) First order derivative spectra of drug, showed λ maxima = 305 nm and λ minima = 280 nm and amplitude difference was measured for the respective concentration of standard and was plotted against concentration and regression equation was calculated. (Method B). Wavelength range of 316 nm to 263 nm was considered for the calculation of area under curve (AUC) for analysis (Method C). The drug followed the Beer-Lambert’s law in the concentration range of 5-30 μg/ml with correlation coefficient (R)=0.999, recovery of the drug was found to be more then 99.60% and relative standard deviation(SD) was found to be less than 2 % for precision studies in all the three methods. Results of the analysis, validated statistically and by recovery studies were found to be satisfactory. The newly developed methods can be used for routine analysis of zolpidem tartrate in bulk and tablet dosage forms.