Development of the spectrophotometric method for the determination of metoprolol in tablets by using bromophenol blue

Beta-blockers is one of the main groups of drugs used in cardiology. Metoprolol belongs to the most famous drugs of this class, because has high selectivity to beta-adrenergic receptors and lipophilicity. By surveying the literature review of metoprolol, it was found that European Pharmacopeia (EP ) have monograph only for substance metoprolol tartare, but not for metoprolol in tablets. Many approaches have been reported for the detection of metoprolol by spectrophotometric and chromatographic methods. However, they have certain disadvantages and make it impossible to use these methods in laboratories where is no HPLC equipment or require the use of toxic solvents, which is negative from the point of view of the principles of «green» chemistry. There is a need for a simple, economic and ecofriendly spectrophotometric methods for the determination of metoprolol tartrate in tablets with less sophisticated equipment and budgets.