High-performance thin-layer chromatography-based methodology for simultaneous estimation of bisoprolol fumarate and telmisartan

Bisoprolol fumarate (BSF) is a cardioselective β-blocker, whereas telmisartan (TLM) is an angiotensin II receptor antagonist. Both drugs in combination are available as a formulation product effective in the management of hypertension. As a rapid and precise analytical method, there is still no high-performance thin-layer chromatographic (HPTLC) method reported for the simultaneous estimation of both the drugs in combination. Therefore, the aim of the present study was to develop a precise, accurate, and sensitive HPTLC method for simultaneous estimation of BSF and TLM in bulk and in formulation product. The separation was achieved by using a mobile phase mixture consisting of methanol‒ethyl acetate‒glacial acetic acid (MeOH‒EA‒GAA; 6:4:0.1, V/V). The retention factor (R_F) for BSF and TLM was found to be 0.435 ± 0.04 and 0.699 ± 0.04, respectively, and the peak areas were determined at 231 nm. The method was subsequently validated as per the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) Q2 (R1) guidelines. A linear relationship was obtained between the concentration ranges and peak areas with correlation coefficient (R²) ≥ 0.999. The developed method was found to be accurate, precise, and robust. The method was then applied for analysis of three different batches of marketed product, and the percent content for BSF and TLM in the formulation was found to be > 98.0% w/w.