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Spiropyran in nanoassemblies as a photosensitizer for photoswitchable ROS generation in living cells.

ABSTRACT: Reversibly controlled generation of singlet oxygen from photosensitizing nanosystems has the benefits of selective cell killing and controllable effect time, but is a challenging option for photodynamic therapies. We report a strategy for integrating photochromic spiropyrans into biocompatible cationic polymers, which involved assembling nucleic acids into functional nanoparticles without introducing additional photosensitizers and imaging agents. We found that spiropyran-containing nanoparticles have photoswitching properties for both fluorescence (with a quantum yield of up to 0.27) and singlet oxygen generation (with a quantum yield of up to 0.22) in aqueous solutions and cells, and demonstrated that spiropyrans in nanoassemblies featuring aggregation-induced enhanced photosensitization and emission could be potentially applied in photodynamic therapy studies on tumor cells.

SUBMITTER: Ji J

PROVIDER: S-EPMC6050604 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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Spiropyran in nanoassemblies as a photosensitizer for photoswitchable ROS generation in living cells.

Ji Jinkai J Li Xiao X Wu Tiantian T Feng Fude F

Chemical science 20180611 26

Reversibly controlled generation of singlet oxygen from photosensitizing nanosystems has the benefits of selective cell killing and controllable effect time, but is a challenging option for photodynamic therapies. We report a strategy for integrating photochromic spiropyrans into biocompatible cationic polymers, which involved assembling nucleic acids into functional nanoparticles without introducing additional photosensitizers and imaging agents. We found that spiropyran-containing nanoparticle ...[more]

PMID: 30079193

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