Introduction

Azelnidipine a calcium channel blocker belongs to BCS class II and S (-) Metoprolol Succinate belongs to BCS class I.

Rationale

Calcium is responsible for inducing smooth muscle contraction. Inhibiting calcium channel will inhibit the contraction of smooth muscles which results in reduction of blood pressure. Metoprolol selectively acts on β-1adrenergic receptor (specifically related to cardiac cells). Metoprolol shows negative ionotropic and chronotropic effect. Thus, it shows synergistic or complementary action azelnidipine.

Objectives

To formulate and evaluate the new combination of antihypertensive drugs and UV and reverse phase chromatography method development for quantification of Azelnidipine and Metoprolol in its formulation.

Materials and Methods

For the simultaneous estimation of Azelnidipine and S (-) Metoprolol Succinate by UV-spectrophotometry two UV-spectrophotometric methods were developed using Schimadzu-1800 UV spectrophotometer. RP-HPLC method was developed using Inertsil ODS C₁₈ (150X4.6 mM; 5 μM) column by flowing solvent system sodium dihydrogen phosphate anhydrous Buffer: Acetonitrile (35:65) at the 1 mL/min. Detection of chromatographic peaks were carried out by employing a 235 nm UV detector.

Results

According to ICH recommendations, the developed methods were validated. The suggested technique demonstrated appropriateness for concurrent determination of azelnidipine and metoprolol using a UV spectrophotometer and HPLC.

Conclusion

The method established via UV-Spectrophotometry and HPLC was evaluated to be unique, easy, accurate and exact. The technique can be applied to routine quality control of bulk and combined dose forms of Azelnidipine and S (-) Metoprolol Succinate in pharmaceutical and drug research laboratories