Light-Triggered Disruption of PAG-Based Amphiphilic Random Copolymer Micelles

The amphiphilic random copolymer of P­(NVP-<i>co</i>-NHPSS) with photocleavable N–O sulfonate side groups has been prepared to investigate the light-triggered disruption of copolymer micelles. Methods of absorption and emission spectra, solution transmittance, dynamic light scattering (DLS), and transmission electron microscopy (TEM) were applied. It was found that P­(NVP-<i>co</i>-NHPSS) could form polymeric nanoaggregates in aqueous solution. And the photocleavage of the N–O bond within copolymer micelles upon 365 nm UV light could be conveniently controlled by changing the irradiation intensity, leading to the disruption of copolymer micelles and the photocontrolled release of Nile red encapsulation. And by encapsulating NaLuF₄:Gd/Yb/Tm UCNPs inside copolymer micelles, the response of the photocleavable N–O bond to the 980 nm laser was much weaker than the response to 365 nm light; however, the photocontrolled release of Nile red could still be effectively triggered by the NIR light of the 980 nm laser