Development and Characterization of Bioadhesive Film Embedded with Lignocaine and Calcium Fluoride Nanoparticles

The formation of biofilm by Streptococcus mutans on the tooth surface is the primary cause of dental caries and periodontal diseases, and fluoride (F) has shown tremendous potential as a therapeutic moiety against these problems. Herein, we report an efficient multi-ingredient bioadhesive film-based delivery system for oral cavity to combat dental problems with an ease of administration. Thiolated chitosan-based bioadhesive film loaded with calcium fluoride nanoparticles (CaF₂ NPs) and lignocaine as a continuous reservoir for prolonged delivery was successfully prepared and characterized. The polygonal CaF₂ NPs with an average particle size less than 100 nm, PDI 0.253, and + 6.10 mV zeta potential were synthesized and loaded in film. The energy dispersive x-ray (EDX) spectroscopy confirmed the presence 33.13% F content in CaF₂ NPs. The characterization of the three film trials for their mechanical strength, bioadhesion, drug release, and permeation enhancement suggested film B as better among the three trials and showed significant outcomes, indicating the potential application of the medicated bioadhesive film. In vitro dissolution studies revealed sustained release pattern of lignocaine and CaF₂ NP following Krosmeyer-Peppas model over 8 h. Franz diffusion studies showed the prolonged contact time of film with mucosa that facilitated the transport of CaF₂ NPs and lignocaine across the mucosa. Hence, the prepared bioadhesive film-based system showed good potential for better management of dental problems. Graphical Abstract.