Design and Characterization of Buccal Films of Benzocaine for Mouth Ulcer

Abstract

Mouth ulcer is very common in recent years, which occurs due to the damage of epithelial tissue and/or lamina propria that finally leads to tissue necrosis. Benzocaine has been used to treat the mouth ulcers due to its excellent local anaesthetic effect that relieves the pain associated with mouth ulcer. Hence an attempt was made to develop and characterize the buccal films of Benzocaine to treat mouth ulcers with an aim of prolonging the drug release and improving the patient convenience. The films were fabricated using the mucoadhesive polymer blend of chitosan and HPMC by solvent casting method and the physico-mechanical, in vitro drug release and ex vivo buccal mucosal permeation characteristics of the films were studied. All fabricated film formulations prepared were smooth and almost opaque, with good flexibility. The weight and thickness of all the formulations were found to be uniform. Drug content in the films ranged from 97–99%, indicating favorable drug loading and uniformity. The inclusion of HPMC, significantly reduced the bioadhesive strength and in vitro mucoadhesion time of chitosan films, although the degree of swelling increased. In vitro drug release and permeation studies in simulated saliva showed a prolonged release for a period of 6 h for all formulations. The formulation with Chitosan: HPMC ratio 1:1, 10% w/w polysorbate 80 and 10% w/w propylene glycol as plasticizers showed the best results which exhibited the cumulative percentage drug release of 87.9 % and the cumulative amount of drug permeation of 7.62mg/cm2 across goat buccal mucosa in 6 h. Drug-excipient interaction studies were carried out using DSC and FT-IR technique; films indicated no chemical interaction between drug and polymers used. Keywords: Benzocaine; mouth ulcer; mucoadhesion; buccal film