Degradable Supramolecular Photodynamic Polymer Materials for Biofilm Elimination

In this work, we fabricated a degradable supramolecular photodynamic polymer (SPP) with an enhanced efficiency of biofilm elimination. The small-molecule photosensitizer, a cationic porphyrin derivative, was grafted to a block polymer backbone (BPB) through a host–guest interaction and metal coordination. The locally enriched cationic photosensitizer in SPP endows a high efficiency to disrupt biofilms due to the generated reactive oxygen species (ROS) around the bacteria under white light illumination, while reducing the cytotoxicity to mammalian cells. After cucurbit[7]­uril was added as a competitive agent, the photosensitizer could be disassociated from the BPB and the antibacterial ability was reduced; also the SPP could be further degraded. As a consequence, the supramolecular photodynamic polymer may become a very promising material for biofilm elimination with an enhanced antibacterial efficacy and degradability to fight against drug-resistant bacteria.