FORMULATION, EVALUATION AND SPECTROSCOPIC VALIDATION OF LABETALOL HYDROCLORIDE SR TABLETS USING VARIOUS VISCOSITY GRADES OF HPMC

Debashrita Sahoo*, Jharna Sahoo, Durga Madhab Kar, M.S. Theivendran and T. Siva Prakash

ABSTRACT

The primary objective of sustained release drug delivery system is to ensure safety and to improve efficacy of drugs as well as patient compliance by controlling the drug release pattern within narrow therapeutic range, leading to minimize the side effect and ensure the safety. The aim of the study is to design, characterize and evaluate Labetalol hydrochloride sustained release tablets using various viscosity grades of HPMC. The principal physiologic action of Labetalol is to competitively block adrenergic stimulation of β-receptors within the myocardium (β1-receptors) and within bronchial and vascular smooth muscle (β2-receptors), and α1-receptors within vascular smooth muscle which causes a decrease in systemic arterial blood pressure and systemic vascular resistance without a substantial reduction in resting heart rate, cardiac output, or stroke volume, apparently because of its combined α- and β-adrenergic blocking activity. The author in the presence study attempts to formulate the sustained release tablets of Labetalol HCl using different viscosity grades of HPMC i.e. HPMC K4m, HPMCK15M, HPMC K100M with different drug polymer ratio to reducing the dosing frequency, minimize the flections of plasma drug concentration, evaluation has been done of the prepared formulation and compared with the standard. The prepared granules were free flowing and characterized for drug content, DSC, X-ray diffraction study and FTIR. The X-ray diffraction study & DSC obtained from various formulations showed no interaction within these formulations. The in-vitro release studies were performed using pH 7.4 phosphate buffer for 12 hours from which the different drug polymer ratios are followed zero order kinetics. The analytical validation by UV spectroscopic method of the formulation for specificity, Linearity, Accuracy, Precision and intermediate precision and stability of the solution over desired period of time is carried out

Keywords: Labetalol Hydrochloride, DSC, FTIR. HPMC, X-ray diffraction study, Analytical validation.