Antibacterial high-genus polymer vesicle as an armed drug carrier

Presented in this paper is an armed high-genus block copolymer vesicle (g = 18) which has excellent blood compatibility and more internal barriers than simple polymer vesicles (g = 0) for controlled anticancer drug delivery. The high-genus vesicle also shows better antibacterial activity against both Gram-positive and Gram-negative bacteria without quaternary ammonium moieties or the loading of any external antibiotics compared to the non-self-assembled individual polymer chains, or a conventional simple vesicle. This high-genus polymer vesicle was prepared by the self-assembly of PMEO(2)MA(20)-b-PTA(20) diblock copolymers in DMF-water, where PMEO(2)MA is thermo-responsive poly[2-(2-methoxyethoxy)ethyl methacrylate] and PTA is pH-responsive and antibacterial poly[2-(tert-butylaminoethyl) methacrylate]. Doxorubicin (DOX) loading/release experiments revealed a retarded release rate of DOX in high-genus block copolymer vesicles than conventional simple vesicles, which could be used as an efficient drug delivery carrier with more internal barriers for drug molecules than conventional simple vesicles. Moreover, this armed drug delivery vehicle makes antibacterial and anticancer therapeutic processes proceed spontaneously, representing a safer and more efficient drug delivery system in nanomedicine.