Regulative peroxidase activity of DNA-linked hemin by graphene oxide for fluorescence DNA sensing

摘要

The inhibition effect of graphene oxide toward the peroxidase activity of DNA-linked hemin was identified and conveniently utilized in the design of a homogenous fluorescence strategy for DNA sensing with high sensitivity. As an active cofactor for a variety of natural enzymes such as horseradish peroxidase and catalase, Fe(Ⅲ)-protoporphyrin Ⅸ (hemin) has attracted extensive research interest for mimicking catalysis in numerous applications. In particular, the regulation of its catalytic activity is very important for obtaining tunable detection signals and achieving high analytical sensitivity. For example, after hemin binds with the guanine quadruplex to form a DNAzyme, the peroxidase activity of hemin can be greatly enhanced compared with that of free hemin.