Fluorinated branched polymer enables Ce6 and IR780 more effective for phototherapy

Phototherapy is gradually becoming a primary technique for treating tumors due to increased efficacy and less side effects. It largely depends on the photosensitizers. Nevertheless, most of photosensitizers show poor stability, how to encapsulate or load them, especially multiple ones, for effective delivery is of paramount importance. To address the challenge, a hyperbranched polymer was prepared by a reversible addition-fragmentation chain transfer polymerization, which is composed of 2,2,3,3-Tetrafluoropropyl methacrylate (TFPMA), bis(2-methacryloyl)oxyethyl disulfide (DSDMA) and poly(oligo ethylene glycol) methyl ether methacrylate (PEGMA). Benefiting from hydrophobic performance of fluorinated segments, this hyperbranched polymers can load hydrophobic IR780 (9%) and Ce6 (12%) due to self-assembly and hydrophobic-hydrophobic interaction. The final formed composite micelles showed good water dispersity, well biocompatibility, and strong stability. Remarkably, they had good photodynamic and photothemal abilities, enabling them to synergistically induce tumor cell apoptosis by oxidative damage and thermal ablation. This work offers a promising composites and strategy for loading photosensitizers stably and effectively towards cancer therapy.