In Situ Phototriggered Disulfide-Cross-Link Nanoparticles for Drug Delivery.

In situ forming redox responsive nanoparticles have been developed based on amphiphilic copolymers-phototriggered disulfide-cross-link macromolecules (PDCM). Upon 405 nm light irradiation, the macrocyclic thiol caged coumarin phototrigger in PDCM can release free thiols, and these free thiols subsequently realize in situ disulfide cross-link via reacting with a pyridyl disulfide group inside the PDCM assembled nanoparticles. The phototriggered disulfide-cross-link strategy can be conducted rapidly, conveniently, and cleanly without adding any cross-linkers or catalysts. Via changing irradiation condition, nanoparticles with different cross-link densities can be formed. These nanoparticles can encapsulate hydrophobic guest molecules with good stability and achieve redox-triggered release under GSH reduction. Intracellular experiments show that these nanoparticles can be used as promising drug carriers.