ASSESSMENT OF PHARMACEUTICAL QUALITY AND RELEASE KINETICS OF METOPROLOL TARTRATE EXTENDED RELEASE TABLETS AVAILABLE IN TURKISH DRUG MARKET

Abstract

Cardioselective β-adrenergic blocker metoprolol tartrate, is used in the treatment of different diseases such as cardiacarrhythmias, hypertension, heart failure, angina pectoris, migraine, and hyperthyroidism. Beside dosage forms of the parenteralampoule and conventional tablets of different manufacturers, there are extended release tablets of metoprolol tartrate in theTurkish Drug Market. In this research work, comparative quality control studies of metoprolol tartrate extended release tablets(original and generic) produced by two different pharmaceutical companies in the Turkey were carried out and evaluatedaccording to the related guidelines. Thickness and diameter, hardness, weight variation, friability, content uniformity anddissolution rate were examined as quality control parameters. A new validated HPLC method for the quantification ofmetoprolol tartrate has been developed. An ACE column (C18, 5 µm, 250x4.6 mm) and acetonitrile:phosphate buffer (30:70,v/v) mobile phase were used for the determination of metoprolol tartrate. The tablets showed extended release for 8 hours(70.74% release from drug A, 76.87% from the drug B). Both products have acceptable hardness, friability and weight variationvalues. Content of the active ingredient of the tablets was consistent with label claim (99.45% for drug A and 96.45% for drugB). The dissolution data were evaluated by model dependent and model independent methods using DDSolver program. Theobtained results showed that release kinetics of both drugs were well fitted with the Korsmeyer-Peppas model.