A simple method to achieve high doxorubicin loading in biodegradable polymersomes

Doxorubicin (Dox), an anthracycline anticancer drug, was successfully incorporated into block copolymer vesicles of poly(trimethylene carbonate)-b-poly(l-glutamic acid) (PTMC-b-PGA) by a solvent-displacement (nanoprecipitation) method. pH conditions were shown to have a strong influence on loading capacity and release profiles. Substantial drug loading (47% w/w) was achieved at pH 10.5. After pH neutralization, aqueous dispersions of drug-loaded vesicles were found stable for a prolonged period of time (at least 6 months) without vesicle disruption or drug precipitation. Dox-loaded vesicles exhibited in vitro pH and temperature-dependent drug release profiles: release kinetics fastened in acid conditions or by increasing temperature. These features strongly support the interest of developing PTMC-b-PGA polymersomes as carriers for the controlled delivery of Dox.

Graphical AbstractDoxorubicin loading was optimized and quantitatively and spatially controlled in polymersomes, which had consequences on release kinetics and drug availability.Figure optionsDownload full-size imageDownload as PowerPoint slide