Prop-2-ynyloxybenzyloxy substituted phthalocyanine-based polymeric nanoparticles: synthesis, photophysical properties and in vitro PDT efficacy

Two prop-2-ynyloxybenzyloxy axially/peripherally substituted zinc/silicon phthalocyanines (YSiPc and YZnPc) were synthesized. They were encapsulated into an amphiphilic block copolymeric micelle polyethylene glycol monomethyl ether-polycaprolactone (MPEG₅₀₀₀–PCL₂₀₀₀) to form polymeric nanoparticles YSiPc@MPEG₅₀₀₀–PCL₂₀₀₀ and YZnPc@MPEG₅₀₀₀–PCL₂₀₀₀. The photophysical and photochemical properties of these polymeric nanoparticles were studied by UV/Vis and fluorescence spectroscopy. The cellular uptake and reactive oxygen species (ROS) production abilities of two polymeric nanoparticles in MCF-7 breast cancer cells were evaluated by confocal laser scanning imaging. YSiPc@MPEG₅₀₀₀–PCL₂₀₀₀ exhibited a higher cellular uptake, higher ROS generation ability as well as higher photodynamic efficacy against MCF-7 cells. YSiPc@MPEG₅₀₀₀–PCL₂₀₀₀ is a promising photosensitizer for photodynamic therapy.