In vitro and in vivo evaluation of chitosan microspheres with different deacetylation degree as potential embolic agent

To evaluate the potential of N-acetylated chitosan microspheres used as a chemoembolic agent in vivo and in vitro. Calibrated spherical chitosan microspheres (CMs) were prepared via Water-in-Oil emulsification method and CMs were acetylated (ACMs). The swelling rate of CMs was greatly affected by pH than that of ACMs and both of them affected by temperature. Microspheres with excellent thermal stability demonstrated controllable degradation in lysozyme solution. Doxorubicin was released from microspheres in vitro and exhibited excellent control release profile. ACMs caused hemolysis less than CMs (<5% of the time). Co-culture with mouse embryo fibroblasts revealed that microspheres have noncytotoxic nature. Microspheres planted in a rat gluteal muscle demonstrated that it were biodegradable and biocompatible. ACMs were performed in rabbit ear embolization model and ischemic necrosis on ear was visible due to the vascular occlusion after 15 days. Acetylated chitosan microspheres could be used as potential biocompatible and biodegradable embolic agents. (C) 2014 Published by Elsevier Ltd.