Borneol-based antisolvent-induced in situ forming matrix for crevicular pocket delivery of vancomycin hydrochloride

Given its safety and apparent low aqueous solubility, borneol may serve as a matrix forming component of anti-solvent based in situ forming matrixes (ISMs) for crevicular pocket targeting. Drug-free and vancomycin hydrochloride-loaded borneol ISMs were evaluated for pH, density, viscosity, contact angle, surface tension, matrix formation, drug release behavior, in vitro degradability and antimicrobial activities. Density and pH values of borneol-based ISMs decreased with increasing borneol concentration. Given their markedly low viscosity could facilitate better injectability. The contact angles of the drug-free and vancomycin HCl-loaded borneol ISMs increased after being in contact with the agarose gel or the bulge tissue of porcine due to phase inversion. A dense borneol crystal matrix formed after using the highly concentrated ISM corresponded to fast matrix formation. The borneol-based ISM exhibited a sustainable drug release longer than 14 days with a diffusion-controlled release mechanism. Moreover, the developed ISM exhibited strong antimicrobial activities against various microbes. Thus, the vancomycin HCl-loaded borneol-based ISM is a potentially effective local anti-solvent-based ISM for periodontitis treatment via crevicular pocket injection.