Increasing target hybridization kinetics by immobilizing DNA probes at Au nanoflower ultramicroelectrode

Although different electrochemical DNA sensors have been widely developed for analytical purpose, the effective way to immobilize DNA probes on basic electrode surface for increasing their binding rate with target is rarely reported. Herein, a new scheme for increasing DNA probes-target hybridization kinetics using gold nanoflower ultramicroelectrode (UME) as DNA probe immobilization surface was developed. In details, the ATP aptamer was selected as the model to demonstrate this E-DNA sensor's properties. Our results showed that the DNA aptamer/ATP hybridization rate obtained at gold nanoflower UME was about 10-fold and 4-fold greater than that obtained at the macroelectrode surface, and even in the homogeneous solution, respectively. This increase of DNA aptamer hybridization rate was confirmed to be related with the smaller size of UME and the specific structure of gold nanoflower.