Optimization of Mucoadhesive Film Reinforced with Functionalized Nanostructured Lipid Carriers (NLCs) for Enhanced Triamcinolone Acetonide Delivery via Buccal Administration: A Box–Behnken Design Approach

This research aimed to develop mucoadhesive buccal films incorporating nanostructured lipid carriers (NLCs) loaded with triamcinolone acetonide (TN-films). A Box–Behnken design was employed as a systematic approach to optimize the formulation. Key components of the NLCs—spermaceti, soybean oil, and polysorbate 80—were considered independent variables. The NLCs were prepared and size-reduced using a combination of hot homogenization and ultrasonic probe techniques. Films were cast using hydroxypropyl methylcellulose (HPMC) as the film-forming agent. The TN-films were characterized based on weight, thickness, tensile strength, elongation at break, contact angle, and surface free energy. Linear regression showed that spermaceti increased film weight and thickness, while polysorbate 80 decreased them. The mechanical strength of the films was primarily influenced by spermaceti; higher concentrations of spermaceti resulted in decreased film strength. Additionally, all independent variables contributed positively to the lipophilicity of the films. The TN-films were found to sustain drug release via a Fickian diffusion mechanism, exhibiting rapid swelling and favorable mucoadhesive properties. Moreover, the TN-films demonstrated superior drug release and permeation to pastes and films loaded with emulsions. These findings suggest that the TN-films represent a promising and effective approach for the buccal delivery of triamcinolone acetonide.