Self-assembly of polysarcosine amphiphilic polymers-tethered gold nanoparticles for precise photo-controlled synergistic therapy

Polymer-induced self-assembly of inorganic nanoparticles has emerged as a powerful strategy for fabrication of stimuli-responsive drug delivery nanosystems. Herein, we designed and synthesized a series of lipoic acid-capped polysarcosine-b-polycaprolactone (PSar-b-PCL) block copolymers. The self-assembly of gold nanoparticles drove by these block copolymers was systematically investigated, and the preparation of near-infrared (NIR) light-responsive PSar-decorated gold nanovesicle (PSGV) was optimized. DOX as anticancer drug was efficiently encapsulated within the cavity of PSGV. The PSGV greatly prevented doxorubicin (DOX) from premature leakage. Mile upon 808 nm laser irradiation, most of loaded DOX was rapidly released, along with the recovery of DOX fluorescence. Impressively, the DOX-loaded PSGV (DOX-PSGV) exhibited much higher cell uptake efficiency when compared to DOX-loaded polyethylene glycol (PEG)-coated gold nanovesicle (DOX-PEGV). Thanks to the synergistic photothermal/chemo therapy, the DOX-PSGV had highly superior antitumor efficacy in established 4T1 tumor model.