Development and Validation of Extractive Spectrophotometric Methods for the Estimation of Telmisartan by Using Smartphone Application

Abstract

Two simple, sensitive, accurate, precise and reproducible extractive colorimetric methods were developed for estimation of Telmisartan in bulk and pharmaceutical dosage form. These methods are based on the formation of colored ion-pair complex of Telmisartan with Bromocresol green (BCG) and Bromocresol purple (BCP) dyes in acidic medium. The complex was extracted in chloroform and estimated quantitatively at 421 nm and 411 nm for BCG and BCP dyes respectively. For estimation of TMS present in the sample, estimation was also done by using Smartphone Application known as PhotoMetrix Pro. Beer Lambert’s law was obeyed over a range of 4-12 μg/ml for TMS with BCG dye by UV (r²= 0.9997) and PhotoMetrix (r²= 0.997) and for BCP dye it was obeyed over a range of 2-10 μg/ml by UV (r²= 0.999) and PhotoMetrix (r²= 0.998). The developed method was successfully applied for estimation of TMS in three commercial product tablet formulation without interference from common additives. The developed method was validated according to ICH Q2 guideline for linearity, range, accuracy, and precision. Comparison for both method UV and PhotoMetrix was done by performing t-test, and results show that there is no significant difference between both methods and hence Photometrix can be used as an alternative to UV for routine analysis of TMS.
 Keywords: Telmisartan, Bromocresol green, Bromocresol purple, Acidic dyes, Colorimetry, UV spectrophotometry, PhotoMetrix.