Fabrication and evaluation of transdermal matrix patches of Metoprolol Tartrate

Abstract

Transdermal drug delivery systems are devices containing drug of defined surface area and overcomes the disad- vantages associated with oral products like first pass hepatic metabolism, reduced bioavailability, dose dumping and dosing inflexibility. These devices allow for pharmaceuticals to be delivered across the skin barrier. The aim of this study is to fabricate and evaluate different polymeric matrix films of HPMC and PVP combination containing Metoprolol tartrate with the objective to avoid first-pass metabolism, improve the therapeutic efficacy, improve the bioavailability and to improve the patient compliance. The patches were prepared by solvent casting method using polymers (HPMC K 100M & PVP) of single or in combination and were dissolved in suitable solvents. The glass surface containing ‘O’ ring is used for casting the film and the prepared transdermal patches were stored in a desiccator until evaluation. The patches were evaluated for thickness, folding endurance test, percentage of mois- ture content, content uniformity, in vitro drug release studies. The thickness of the patches varied from 0.21 to 0.28 mm, folding endurance of the films varied from 150 to 191 no of folds. The formulation F-I (HPMC 2%) and F- II (PVP 2%) has shown release 96.66 % and 92.25% at 12th hour, F-III (1% HPMC and1% PVP) and F-IV (0.5%HPMC and 0.5% PVP) has shown the drug release of 98.331% and 94.55% at 12th hour respectively and F-V formulated with PVP 0.5 % and HPMC 1.5% has shown release 99.21% at 12th hour. Hence, based on the drug release and physico chemical evaluation, the Formulation F-V is considered as an optimized formulation which shows higher percentage of drug release with diffusion mediated mechanism and also satisfies the objective of the present study.