Spatiotemporal Control Release of pH-Responsive Polymeric Micelles via Photochemically Induced Proton Generation

Spatiotemporal control is important in biomedical applications for guided drug delivery and release at desired location. Herein, we provide a new remote-controlled drug delivery system by simply combining pH-responsive polymeric micelles [poly(ethylene glycol)-block-poly(2-(diisopropylamino) ethyl methacrylate), mPEG-b-PDPA] with photoacid generators (PAGs) to actively control the local pH variation via photochemical induced proton generation. The dual chemotherapy drug doxorubicin- (DOX) and PAG-loaded micelles (P-PD) possess good storage stability, high drug loading content, and excellent light remote-controlled drug release behavior. An in vitro cytotoxicity study shows P-PD micelles have better cell growth inhibition efficiency under light irradiation as compared to free DOX, individual DOX, or PAG-loaded micelles. Intracellular DOX distribution confirms the more drugs release upon light irradiation. These results indicate remote-controlled drug release renders the drugs more efficiently to serve their function and reduce the need for high dosage. We believe this P-PD micelle is a promising spatiotemporally controlled drug delivery system for cancer therapy.