One-pot synthesis of glycopolymer-porphyrin conjugate as photosensitizer for targeted cancer imaging and photodynamic therapy.

One-pot system combining multi-reactions is used to synthesize novel porphyrin-glycopolymer conjugates. Sodium mercury amalgam is used to catalyze the reactions: 1) reduction of RAFT polymerized poly(2-(methacrylamido) glucopyranose) (PMAG), 2) converting protoporphyrin to protoporphyrinogen, 3) thiol-ene coupling reaction of PMAG and protoporphyrinogen. The product is oxidized in the same pot to generate the final porphyrin-PMAG conjugates. The resulting conjugates are characterized by NMR, GPC, UV-Vis, and fluorescence spectroscopy. Glycoparticles (≈ 200 nm) bearing glucose units are formed by dissolving the conjugates in water. Glycoparticles show enhanced binding ability toward Con A, bind K562 cells efficiently and kill these cells under light irradiation in dose and light treatment length dependent manners, illustrating the potential biological applications of the conjugates as photosensitizer for cancer imaging and photodynamic therapy.