Photodynamic mechanistic regulation of conjugated polymers for synergistic photodynamic-chemotherapy

Abstract

In this work, we report a side-chain engineering strategy to switch photodynamic pathways of poly(p-phenylene ethynylene, PPE) derivatives. Neutral PPE1 lacks photosensitivity, cationic PPE2 selectively generates singlet oxygen (1O2) via a type-II mechanism, while zwitterionic PPE3 produces superoxide anion (O2−•) through a type-I process. Notably, side-chain functionalization concurrently modulates their platinum (Pt)-binding affinities. The resulting PPE3-Pt nanoplatform undergoes DNA-triggered Pt release, restoring ROS generation and enabling synergistic chemo-photodynamic therapy.