Hydroxypropyl methylcellulose stabilized clove oil nanoemulsified orodispersible films: Study of physicochemical properties, release profile, mucosal permeation, and anti-bacterial activity

Hydroxypropyl methylcellulose (HPMC)-based nanoemulsions for quick dissolving orodispersible (OD) films were prepared to encapsulate clove oil (CO) to harness its anti-bacterial properties. The influence of additives maltodextrin, pectin, and glycerol on the OD films was studied. The nanoemulsion particle size varied from 135 nm to 195 nm. A decrease in tensile strength and, an increase in elongation at break and opacity were observed in OD films compared to neat HPMC film. The AFM images showed an increase in HPMC films' average roughness from 6.95 to 90 nm after adding CO and additives. The additives controlled CO in-vitro release from HPMC following the Higuchi model. The ex-vivo permeation through porcine mucosal membrane was 9-33 % while the permeation coefficient and flux were 0.282-0.879 cm s^-1 and 0.191-1.318 μg cm^-2 s^-1, respectively. The OD films exhibited significant inhibition of Staphylococcus aureus, Streptococcus mutans, and Porphyromonas gingivalis suggesting their therapeutic potential in oral healthcare.