DNA Nano-netting Intertexture on Carbon Electrodes
摘要
Native calf thymus double stranded DNA (ct-dsDNA) is successfully immobilized from solution onto carbon substrates by covalent linkages under an optimized deposition potential of 1.8±0.3V vs. 50mmol/L NaCl-Ag/AgCl. The long chain DNA fabricates a layer of well conductive nano-netting intertexture, which is stable in pH 14 alkaline solution and in boiling water. The ct-dsDNA modified carbon fiber disk electrode shows two to three orders of magnitude enlarged electrode effective surface area and similarly enlarged voltammetric responses to Co(phen)3^3+ and dopamine. Thermal dissociated single stranded ct-DNA can also lead to similar result. This modified electrode will find wide applications in the fields of DNA-based electrochemical biosensors.