The substituted zinc(II) phthalocyanines using sulfur bridge as the linkages. Synthesis, red-shifted spectroscopic properties and structure-inherent targeted photodynamic activities

Zinc(II) phthalocyanines are favorable candidates as photosensitizers (PSs) for photodynamic therapy (PDT). However, zinc(II) phthalocyanines also suffer from poor water solubility and low tumor-targeting ability. In this study, a novel zinc(II) phthalocyanine tetra-substituted with sulphonates using ?sulfur bridge? as the linkages was developed (ZnPc3), which exhibits high water-solubility and natural tumor targeting. Furthermore, ZnPc3 possesses red-shifted absorption and fluorescence spectra as compared to the unsubstituted zinc(II) phthalocyanine. In vivo fluorescence imaging indicates that ZnPc3 possesses an excellent tumor selectivity after intravenous injection without any help of targeting ligands or extra nanomaterials. The results of in vivo phototherapy evaluation suggest that ZnPc3-induced PDT could effectively inhibit the tumor growth in a mouse model.

Automated summary

A novel zinc(II) phthalocyanine tetra-substituted with sulphonates using "sulfur bridge" as the linkages was developed in this study, which exhibits high water solubility and natural tumor targeting. ZnPc3 possesses red-shifted absorption and fluorescence spectra compared to the unsubstituted zinc(II) phthalocyanine, showing excellent tumor selectivity after intravenous injection without the need for targeting ligands or extra nanomaterials. In vivo phototherapy evaluation suggests that ZnPc3-induced PDT effectively inhibits tumor growth in a mouse model.