Stability-Indicating RP-HPLC and CE Methods for Simultaneous Determination of Bisoprolol and Perindopril in Pharmaceutical Formulation: A Comparative Study.

Two fast, accurate and selective stability-indicating methods were developed and validated for the simultaneous determination of bisoprolol, perindopril and three of their possible degradation products. The first proposed method was a gradient reversed phase-high-performance liquid chromatography (HPLC) method, whereas the second was a capillary electrophoresis method. The structures of the obtained degradation products were elucidated using infrared and mass spectrometry. They were also confirmed to be either a drug impurity in the British Pharmacopoeia or a precursor to such impurity. The linearity for bisoprolol and perindopril was achieved in the range of 1-20 μg mL-1 and 5-30 μg mL-1 for HPLC and capillary electrophoresis methods, respectively. The proposed methods were validated according to the International Conference on Harmonisation guidelines. The HPLC method proved to be more sensitive and succeeded in the quantitative determination of the obtained degradation products. Also, it was able to quantify perindopril impurity up to three times lower than the desired limit set by the British Pharmacopoeia. They were successfully employed in the determination of bisoprolol and perindopril in their combined pharmaceutical formulation.