Light-triggered disassembly of photo-responsive gold nanovesicles for controlled drug release

Abstract

In this study, we report the light-triggered disassembly of gold nanovesicles (GVs) from amphiphilic photo-responsive block copolymer (polystyrene-b-polyethylene glycol, PS–C4–PEG) tethered gold nanoparticles (Au NPs) for controlled drug release. Amphiphilic photo-responsive PS–C4–PEG, with the group of truxillic acid at the junction of the two blocks, is prepared and grafted on the surface of Au NPs. GVs with tunable size and structures can be generated by self-assembly of the PS–C4–PEG tethered Au NPs in a selective solvent. Drugs can be effectively encapsulated into the cavity of the GVs during the self-assembly process. Moreover, under UV light irradiation, the PS–C4–PEG on the Au NPs can be decomposed, resulting in the formation of defects on the surface of the GVs, and sustainable drug release can thus be achieved. More interestingly, the entire contour of the GVs remains after UV light irradiation due to the slow debonding of truxillic acid, which is important for combined chemo- and photothermal-therapies. With these features, the obtained GVs can be used as a multifunctional platform for cancer diagnosis, bioimaging, and combined therapies.