posted on 2020-01-22, 18:49authored byChaochao Wang, Peiran Zhao, Dawei Jiang, Guoliang Yang, Yudong Xue, Zhongmin Tang, Meng Zhang, Han Wang, Xingwu Jiang, Yelin Wu, Yanyan Liu, Weian Zhang, Wenbo Bu
The
aggregation of hydrophobic photosensitizers limits the therapeutic
effect of photodynamic therapy (PDT). Improving the hydrophilicity
of photosensitizers can reduce their aggregation for enhancing PDT.
Herein, a nanosystem (TPFcNP) is developed by a hydrophobic photosensitizer
5,10,15,20-tetrakis(4-methacryloyloxyphenyl)porphyrin (TMPP) containing
multiple carbon–carbon double bonds and a ferrocene-containing
amphiphilic block copolymer (PEG-b-PMAEFc), which
catalyzes hydrogen peroxide (H2O2) to produce
hydroxyl radicals (•OH) in a tumor microenvironment
by the Fenton reaction. The •OH could catalyze the addition reaction between
the carbon–carbon double bonds of TMPP and overexpressed water-soluble
glutathione (GSH) in tumor cells, which greatly improves the hydrophilicity
of photosensitizers and reduces their aggregation. Experiments in
vitro and in vivo have proved that this strategy significantly enhances
the therapeutic efficacy of PDT. Catalyzing intracellular reactions
in situ by making use of the tumor microenvironment will open up a
new opportunity to solve the aggregation of materials in the tumor
for cancer treatment.