Preparation of honokiol-loaded chitosan microparticles via spray-drying method intended for pulmonary delivery.

It has been demonstrated that spray-drying is a powerful method to prepare dry powders for pulmonary delivery. This paper prepared dispersible dry powders based on chitosan and mannitol containing honokiol nanoparticles as model drug. The results showed that the prepared microparticles are almost spherical and have appropriate aerodynamic properties for pulmonary delivery (aerodynamic diameters was between 2.8-3.3 microm and tapped density ranging from 0.14-0. 18 g/cm(3)). Moreover, surface morphology and aerodynamic properties of the powders were strongly affected by the content of mannitol. Fourier transform infra-red (FTIR) spectrum of powders indicated that the honokiol nanoparticles were successfully incorporated into microparticles. In vitro drug release profile was also observed. The content of mannitol in powders significantly influenced the release rate of honokiol from matrices.