Preparation and evaluation of buccal patches of losartan potassium using hydrophilic polymers

Abstract

Losartan potassium is an Angiotensin II receptor antagonist with a half life of 1.5-2 hrs and an oral bioavailability of only 33% due to extensive first pass metabolism. Mucoadhesive buccal films of losartan potassium were prepared using hydroxypropyl methyl cellulose (HPMC 5cps and K100M), hydroxy propyl cellulose (HPC), Polyvinyl pyrrolidone K-30 (PVP K-30), sodium carboxy methyl cellulose (SCMC). FTIR analysis of formulations shows no interaction between drug and polymers. The films were subjected to physical investigations such as uniformity of thickness, weight, drug content, folding endurance, surface pH, percentage moisture absorption, water vapour transmission rate and mucoadhesive strength. The mucoadhesive force, swelling index, was higher for those formulations containing higher percentage of HPMC. In vitro drug release studies reveal that all films exhibited sustained release in the range of 72.09 to 97.10 % for a period of 8 hours. The data was subjected to kinetic analysis which indicated non fickian diffusion for all formulations except few. Ex vivo release studies through goat cheek mucosa indicate that films containing higher percentage of the mucoadhesive polymer SCMC showed slower permeation of the drug for 12 hours.