Application of UV-spectrophotometric methods for estimation of tenofovir disoproxil fumarate in tablets.

Two new, simple and cost effective UV-spectrophotometric and first order derivative methods were developed for estimation of tenofovir disoproxil fumarate in bulk and tablets. Tenofovir disoproxil fumarate was estimated at 260 nm in 0.1N HCl. In first order derivative, it showed amplitude at 273 nm. In both the methods linearity was found to be in the range of 5-40 micro/ ml; for UV-spectrophotometric method (Y=0.02586 x +0.0083; r(2)=0.9999) and for first order derivative spectrophotometric method (Y=0.00132 x +0.00035; r(2)=0.9995), respectively. These methods were tested and validated for various parameters according to USP guidelines. The quantitation limits were found to be 1.546 and 1.986 micro/ ml, for both the methods. The proposed methods were successfully applied for the determination of tenofovir disoproxil fumarate in pharmaceutical formulations. The results demonstrated that the procedure is accurate, precise and reproducible (relative standard deviation <2%), while being simple, cheap and less time consuming and can be suitably applied for the estimation of tenofovir disoproxil fumarate in different dosage forms.