Abstract

It is very challenging to completely break the corona symmetry of polymer vesicles as usually their inner and outer coronas have the same constituents. Herein, we propose a novel micelle-to-vesicle strategy to achieve this goal. First, a poly(ethyleneoxide)113-b-poly[N-isopropylacrylamide45-stat-7-(2-methacryloyloxyethoxy)-4-methylcoumarin10]-b-poly(2-(diethylamino)ethylmethacrylate)28[PEO113-b-P(NIPAM45-stat-CMA10)-b-PDEA28] triblock copolymer was synthesized and self-assembled into micelles, which were then transformed into asymmetrical vesicles. The PEO block formed the outer corona of the vesicles, the PDEA block formed the inner corona of the vesicles (initially acted as the core-forming block of micelles), and the P(NIPAM-stat-CMA) block formed the membrane of vesicles (initially acted as the middle corona or the shell of micelles). Symmetry breaking was achieved during the micelle-to-vesicle transition where the locations of the inner and the outer coronas of vesicles were predetermined. This asymmetric structure was confirmed by selective decoration with gold nanoparticles on the PDEA inner coronas. Furthermore, the inner coronas could efficiently prevent unwanted doxorubicin (DOX) leakage at physiological conditions by turning themselves into an inner wall. Overall, we have hereby demonstrated a novel approach to prepare well-defined asymmetric vesicles through a finely controlled micelle-to-vesicle transition.

文章链接：Macromolecules 2021, DOI: 10.1021/acs.macromol.1c00060.