Three spectrophotometric quantitative analysis of bisoprolol fumarate and telmisartan in fixed-dose combination utilizing ratio spectra manipulation methods

Abstract Hypertension is a common chronic disease that requires several treatment regimens. As a result, limiting the dosage of these medications is critical to patient compliance. Therefore, bisoprolol fumarate and telmisartan have been recently made in a fixed-dose combination rather than individual doses to manage blood pressure. Hence, the UV absorption spectra of bisoprolol fumarate and telmisartan displayed a significant overlap. Therefore, augmentation of three simple, precise, and selective spectrophotometric methods relying on manipulation of ratio spectra, specifically ratio difference, first derivative, and mean centering of ratio spectra, have been validated, described, and verified for simultaneous measurement of bisoprolol fumarate and telmisartan in pure form and their fixed dose combination. The ratio difference method relies on measuring the amplitude difference between the ratio spectra’s values at 210 and 224 nm for bisoprolol and between 255 and 265 nm for telmisartan. On the other hand, the first derivative of the ratio spectra technique is based on the measurement of amplitude signals at 232 nm and 243 nm of the derived spectra for bisoprolol and telmisartan, respectively. Furthermore, the mean centering of the ratio depends on measuring the mean-centered ratio spectra's values at 223 nm for bisoprolol and 245 nm for telmisartan. The established procedures underwent validation in compliance with ICH recommendations. The developed techniques are precise and accurate and have the potential to be successfully used for estimating bisoprolol and telmisartan in their combined dosage form.