Covalently synthesized graphene oxide-aptamer nanosheets for efficient visible-light photocatalysis of nucleic acids and proteins of viruses

A novel photocatalyst, graphene oxide (GO) functioned aptamer, was covalently synthesized and characterized as being composed of photosensitive GO and target recognition aptamer. Aptamer enhanced photocatalytic activities of GO were studied under broad visible-light spectrum. The complex photocatalyst effectively inactivated viruses, and damaged the proteins capsid and nucleic acids of viruses in irradiation. Subsequently, the proteins posed carbonylation and the nucleic acid bases (especially for guanosine) received oxidized modification. GO was reduced by loss of oxygen elements. GO-aptamer and viruses constituted a redox system under visible-light irradiation. The photocatalysis paths involved energy transfer (generation of singlet oxygen), electron transfer (generation of anion radicals) and water dissociation (generation of the precursor to the hydrated electron). GO-aptamer is a smart photocatalyst to selectively photocatalyze of nucleic acids and proteins, which is attractive in environment protection, biochemical engineering and phototherapy.