Intracellular pH-sensitive dextran-based micelles as efficient drug delivery platforms

As drug delivery systems, stimuli-responsive polymer micelles hold great potential in cancer chemotherapeutics to improve therapeutic efficiency and eliminate organism adverse effects. Here, pH-sensitive polymeric micelles based on dextran-g-benzimidazole were designed and used for intracellular anticancer drug delivery. The anticancer drug doxorubicin (DOX) was effectively loaded into the micelles via hydrophobic interactions. In vitro release studies demonstrated that the release of loaded DOX was greater and faster under acid conditions such as in carcinomatous areas (pH < 6.8) than in physiological conditions (pH 7.4). MTT assays and flow cytometric analyses showed that DOX-loaded micelles had higher cellular proliferation inhibition towards HeLa and HepG2 cells than pH-insensitive controls. These pH-sensitive micelles with significant efficiency for intracellular drug release will be beneficial to the future of in vivo biomedical applications. (c) 2014 Society of Chemical Industry