Vertical graphene nanoflakes for the immobilization, electrocatalytic oxidation and quantitative detection of DNA

Vertical graphene nanoflake integrated films having a high density of edge planes have been used as an electrochemical platform to systematically investigate the immobilization, electrochemical oxidation kinetics and direct quantitative determination of natural DNA. Consistently, both transmission electron microscopy and atomic force microscopy observations demonstrate the presence of a self-assembled monolayer of native DNA, immobilized on the graphene nanoflakes. Graphene shows excellent electrocatalytic activity for the electrooxidation of double stranded DNA, better than carbon nanotubes and glassy carbon, due to the abundance of electrocatalytic graphene edges present not only at the top but also along the sides of each graphene nanoflake.