Fig. 1

Preparation and characterization of phototargeted nanoparticles. a Phototargeting intravenously administered nanoparticles to choroidal neovascularization. b Schematic of light-triggered activation of the nanoparticle. c Synthesis of the polymer chain functionalized with caged CPP ([CPP]). d Transmission electron microscopy (TEM) image of NP-[CPP]. The scale bar is 50 nm. e Fluorescence emission spectra of NP-[CPP] and NP-[CPP] irradiated for 1 min (50 mW cm⁻², 400 nm) in PBS, the emission maxima are labelled. f ¹H NMR spectra of free CPP and different nanoparticles in D₂O, with the signature phenylalanine proton peaks highlighted in the blue rectangle. NP-CPP is the nanoparticle formed from CPP-PEG-PLA and mPEG-PLA (1:4 weight ratio). Irradiation was with a 400 nm LED for 1 min at 50 mW cm⁻². g Photocleavage of NP-[CPP] in PBS (0.5 mg mL⁻¹), as determined by HPLC (detected at 390 nm absorbance), after continuous irradiation (50 mW cm⁻², 400 nm) (data are means ± SD; n = 4 independent experiments)