Near-infrared uncaging or photosensitizing dictated by oxygen tension.

ABSTRACT: Existing strategies that use tissue-penetrant near-infrared light for the targeted treatment of cancer typically rely on the local generation of reactive oxygen species. This approach can be impeded by hypoxia, which frequently occurs in tumour microenvironments. Here we demonstrate that axially unsymmetrical silicon phthalocyanines uncage small molecules preferentially in a low-oxygen environment, while efficiently generating reactive oxygen species in normoxic conditions. Mechanistic studies of the uncaging reaction implicate a photoredox pathway involving photoinduced electron transfer to generate a key radical anion intermediate. Cellular studies demonstrate that the biological mechanism of action is O₂-dependent, with reactive oxygen species-mediated phototoxicity in normox

SUBMITTER: Anderson ED 

PROVIDER: S-EPMC5476797 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature