A Biodegradable and Amphiphilic Linear-Dendritic Copolymer as a Drug Carrier Platform for Intracellular Drug Delivery

In this work, a biodegradable linear-dendritic copolymer composed of methoxypolyethylene glycols (mPEG) and a third generation glycolic acid oligomer based dendron is synthesized. The amphiphilic copolymer can self-assemble into polymeric micelles in aqueous solution with a low critical micelle concentration (CMC). Hydrophobic doxorubicin (DOX) is incorporated into the micellar core via the dialysis method with a high drug loading content of 21.2%. The drug release result implies that the encapsulated drug can be released rapidly at pH 5.0, due to the hydrolysis of the ester bond resulting in quick disassembly of drug-loaded micelles. Moreover, the results of fluorescence microscopy imaging and flow cytometry measurements demonstrate that the drug carriers can be internalized and DOX released rapidly from them upon endocytosis. Importantly, this drug delivery system exhibits excellent performance to inhibit cancer cell proliferation.