The hydroxypropyl methylcellulose-sorbitol thin film containing a coconut shell of liquid smoke for treating oral ulcer

This study aimed to develop an hydroxypropyl methylcellulose-sorbitol (HPMC-sorbitol) thin film as a targeted drug delivery system for coconut shell liquid smoke (CSLS) to effectively treat oral ulcers. The HPMC-sorbitol thin film containing CSLS was created using solvent-casting methods. The resulting thin film underwent comprehensive analysis for shrinkage rate, weight, thickness, water absorption rate, swelling, dissolution, and disintegration time. The producible HPMC-sorbitol thin film containing CSLS exhibited a thickness of 34.89 ± 0.55 μm and a weight of 307.58 ± 10.76 mg, containing phenol and 13-octadecenoic acids. Notably, its swelling, disintegration, and dissolution times were approximately 5 min faster than the blank film. In vitro testing on BHK21 and 7F2 cells demonstrated the thin film's ability to maintain cell viability. In an in vivo oral ulcer model, the thin film reduced neutrophil recruitment, increased macrophage recruitment, and fostered fibroblast proliferation. The HPMC-sorbitol thin film containing CSLS emerged as an effective and well-tolerated delivery system for oral ulcer treatment. Its controlled release mechanism, precise dosing, and protective covering characteristics contribute to enhanced therapeutic outcomes, positioning it as a promising candidate for further development in oral ulcer treatment to improve human health.