DNA biosensor by self-assembly of carbon nanotubes and DNA to detect riboflavin

The fabrication of biosensors via self-assembly of single-walled carbon nanotubes (SWNTs) and DNA on a platinum electrode was presented in this paper. The carboxylic SWNTs were assembled on an amine-modified platinum electrode surface and followed by the assembly of NH2-DNA with the carboxyl-amine coupling. The decorated surface was characterized by Field Emission Electron Microscopy (FEG-SEM) and electrochemical experiments, which showed that the reaction of DNA–SWNTs biosensor was quasi-reversible. The mechanism of DNA and riboflavin (VB2) was studied by cyclic voltammetry and UV–Vis spectroscopy. The fabricated SWNTs-reinforced biosensor exhibits high sensitivity and low detection limit for the tested VB2 compared to the reported methods.