Highly Sensitive Electrochemical Sensor for the Determination of 8-Hydroxy-2′-deoxyguanosine Incorporating SWCNTs-Nafion Composite Film

8-hydroxy-2′-deoxyguanosine (8-ohdg) is a typical biomarker of oxidative dna damage and has attracted much attention in recent years since the level of 8-ohdg in body fluids is typically associated with various diseases. in this work,a simple and highly sensitive electrochemical sensor for the determination of 8-ohdg was fabricated incorporating single wall carbon nanotubes- (swcnts-) nafion composite film coated on glassy carbon electrode. nafion was chosen as an optimal adhesive agent from a series of adhesive agents and acted as a binder,enrichment,and exclusion film. due to the strong cation-exchange ability of nafion and the outstanding electronic properties of swcnts,the prepared swcnts-nafion film can strongly enhance the electrochemical response to oxidation of 8-ohdg and efficiently alleviate the interferences from uric acid and ascorbic acid. the oxidation peak currents are linear with the concentration of 8-ohdg in the range of 0.03 to 1.25 m with a detection limit of 8.0 nm (s/n = 3). this work demonstrates that swcnts-nafion film can improve the sensitivity,selectivity,reproducibility,and stability,making it an ideal candidate for electrochemical detection of 8-ohdg. © 2015 lingfei yang et al.