Self-assembly of photosensitive and chemotherapeutic drugs for combined photodynamic-chemo cancer therapy with real-time tracing property

Abstract Herein, an amphipathic polymeric photosensitizer, designated as PEGylated distyryl boron dipyrromethenes with real-time tracing property, is synthesized as a kind of multifunctional carrier to load drugs for combined photodynamic-chemo therapy. The hydrophilic PEG side chains on the carriers prolong its blood circulation time and the self-assembly capacity of PEGylated distyryl boron dipyrromethenes effectively solves the problem of low drug loading efficiency and difficulty in drug release. Meanwhile, with the assistance of the photochemical internalization effect more carriers are taken up and accumulate in the cancer cells. Moreover, the autofluorescence of BODIPY can trace and visualize the carriers in cells or tissues and the damage of reactive oxygen species (ROS) to the multidrug resistance (MDR) transporter proteins can overcome MDR in cancer chemotherapy. The IC 50 of PEGylated BODIPY is 250 μg/mL while the IC 50 decreased to 100 μg/mL for Dox@PEGylated BODIPY. As shown in our experiment the self-carriers itself without loading other bioactive constituents can obviously inhibit the growth of cancer cells, and the therapeutic effect is improved after the loading of Dox, indicating the amphipathic polymeric photosensitizer with tracing and self-assembling properties a potential multifunctional cancer treatment platform.