Formulation and Evaluation of a Polyherbal Mucoadhesive Buccal Film Containing Syzygium aromaticum, Glycyrrhiza glabra, and Aloe vera for Localized Oral Antimicrobial and Ulcer Management

Research Article

Abstract

Localized inflammatory lesions and microbial infections of the oral mucosa, such as recurrent aphthous stomatitis, often regarded as a therapeutic challenge due to rapid salivary clearance and mechanical displacement of conventional topical formulations. This study describes the design, preparation, and biophysical characterization of a polyherbal mucoadhesive buccal film engineered for the sustained delivery of bioactive extracts from Syzygium aromaticum (clove), Glycyrrhiza glabra (liquorice), and Aloe vera gel. The films were fabricated using a polymeric blend of hydroxypropyl methylcellulose and Carbopol 934 by solvent casting optimized with glycerol as a plasticizer. The resulting formulations were subjected to rigorous physicochemical and mechanical profiling, including thickness uniformity, weight variation, folding endurance, surface pH, swelling kinetics, and in vitro disintegration behavior. The optimized buccal films exhibited a highly uniform thickness of 0.42 ± 0.03 mm, a swelling index of 30.4 ± 1.8%, and a surface pH of 6.50 ± 0.08, matching the physiological range of human saliva to prevent mucosal irritation. Mechanical evaluation showed a folding endurance exceeding 100 folds, indicative of high structural flexibility. In vitro microbiological assays revealed a distinct zone of inhibition of 16.2 ± 0.8 mm against oral pathogens, validating the preserved antimicrobial efficacy of the encapsulated phytoconstituents. These results show that the integrated polymeric matrix successfully prolongs localized drug retention, offering a stable, flexible, and clinically viable mucosal patch for treating oral ulcerative and infectious conditions.