Highly sensitive methyltransferase activity assay and inhibitor screening based on fluorescence quenching of graphene oxide integrated with the site-specific cleavage of restriction endonuclease.

We report a sensitive and selective approach for the DNA methyltransferase (MTase) activity assay and MTase inhibitor screening by coupling the fluorescence quenching of graphene oxide with site-specific cleavage of a restriction endonuclease.