The Application, Neurotoxicity, and Related Mechanism of Cationic Polymers∗∗Conflict of Interests: All the Figures and Table in “The application, neurotoxicity, and related mechanism of cationic polymers” are original, unpublished materials designed and prepared by Yubin Li and Dianwen Ju. The authors declared that there’s no conflict of interests.

Abstract This chapter introduces neurotoxicity and related mechanism of cationic polymers. It starts by presenting classification of cationic polymers including chitosan, poly( l -lysine), polyethyleneimine, poly(lactic-co-glycolic acid), poly(ester amine)s, poly(2-(dimethylamino)ethyl methacrylate), poly(amidoamine) dendrimers, and their related applications in nanomedicinal field. It then presents neurotoxicity of different cationic polymers. The end of the chapter explains the related mechanisms of cationic polymer-induced neurotoxicity, including physicochemical and biochemical mechanisms. Physicochemical mechanisms mainly include charges, size, and shape of cationic polymers; biochemical mechanisms mainly focus on apoptosis, necrosis, reactive oxygen species, autophagy, and inflammation triggered by cationic polymers.