Design and evaluation of buccal mucoadhesive patches containing an anti hypertensive prodrug Trandolapril

Abstract

The buccal region offers an attractive route for systemic drug delivery. Trandolapril is an ACE inhibitor widely used as an antihypertensive agent shows less oral bioavailability as it undergoes first pass metabolism. Trandolapril patches were prepared using HPMCK4M, Chitosan, HPMCP, PVP and PVA. FTIR and DSC studies revealed that there was no interaction between trandolapril and polymers. Gas phase chromatography was carried to estimate the residual Methanol, acetic acid and dichloromethane. The patches were evaluated for their thickness, folding endurance, weight uniformity, content uniformity, swelling behaviour, tensile strength, and surface pH. The tensile strength was higher for formulations containing HPMCP and HPMCK4M. In vitro release studies were conducted for trandolapril loaded patches in 6.6 pH phosphate buffer solution. Patches containing chitosan and HPMCK4M exhibited greater release than other formulations containing HPMCP, PVP, PVA and HPMCK4M. Patches exhibited drug release in the range of 63.8 to 99.9% in 8 hrs. Data of in vitro release from patches were fit to different equations and kinetic models to explain release profiles. Many of the buccoadhesive systems followed zero-order release kinetics. Buccoadhesive patches of trandolapril can be developed as potential controlled release formulations for the treatment of hypertension.