A novel composite drug delivery system: honokiol nanoparticles in thermosensitive hydrogel based on chitosan.

In this article, a novel composite drug delivery system, honokiol nanoparticles in biodegradable hydrogels based on chitosan (CS) and beta-glycerophosphate (beta-GP), was prepared. CS/beta-GP solution was liquid at room temperature and turned into gel as temperature increased. With increase in beta-GP concentration, the sol-gel transition temperature decreased accordingly. Honokiol nanoparticles with diameter of about 30 nm were prepared by emulsion solvent evaporation method. The sol-gel transition temperature of CS/beta-GP system decreased as F-127 presented in honokiol nanoparticles. In vitro release profiles were studied, the results showed that honokiol could be slowly released from CS/beta-GP gel over at least 2 weeks and the release rate was greatly influenced by initial drug loading. The described injectable hydrogels based on chitosan (CS) and beta-glycerophosphate (beta-GP) might have potential application as local drug delivery for honokiol.