Silicon nanocrystals as photosensitizers of active oxygen for biomedical applications

Silicon nanocrystals dispersed in water have been used to photosensitize the generation of active oxygen. The photosensitizing efficiency has been estimated through the quenching of the exciton photoluminescence of silicon nanocrystals. Experiments have revealed a strong (up to 80%) decrease in the number of cancer mouse fibroblast cells when they come into contact with photoexcited silicon nanocrystals. The obtained results show that the use of silicon nanocrystals for biomedical applications, in particular, for photodynamic therapy of cancer, is feasible.

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