Cyclosporine A/porous quaternized chitosan microspheres as a novel pulmonary drug delivery system

N-[(2-Hydroxyl)-propyl-3-trimethyl ammonium] chitosan chloride (HTCC), a hydrosoluble chitosan derivative, has been extensively investigated as a class of drug delivery vehicles because of its unique features. However the studies on HTCC for pulmonary delivery systems have been rarely conducted. This study aimed to design porous microspheres (MS) containing cyclosporine A (CsA) using HTCC as the carrier. The physicochemical properties and biocompatibility of the MS were evaluated. The in vivo efficacy of MS was evaluated in an asthmatic rat model after pulmonary administration. The results showed that porous MS suitable for inhalation could be readily produced by spray drying method. Optimized porous MS in this study exhibited to be biocompatible and safe to use in the lung, and they were effective in suppression of inflammation in the asthmatic rat model. Above all, our results suggested that HTCC porous MS are promising drug carriers for pulmonary drug delivery. [GRAPHICS]