A novel signal enhancement strategy for the detection of DNA oxidative damage biomarker 8-OHdG based on the synergy between β-CD-CuNCs and multi-walled carbon nanotubes.

To propose a novel signal enhancement strategy based on the synergy between β-CD-CuNCs and multi-walled carbon nanotubes (MWCNTs) for the detection of DNA oxidative damage biomarker 8-Hydroxy-2'-deoxyguanosine (8-OHdG).The sensor was constructed with the β-CD-CuNCs-MWCNTs-nafion film and successfully used for the quantitative detection of 8-OhdG in the presence of biomolecules such as ascorbic acid (AA) and uric acid (UA). To investigate the surface morphology of the modified electrode, Transmission Electron Microscopy (TEM), Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS) were performed on bare and modified electrodes.According to Differential Pulse Voltammetry (DPV) results, there was a linear relationship between peak current and concentration of 8-OhdG, ranging from 1.0×10-7 to 1.0×10-6 mol/L (R2=0.9926) and 1.0×10-6 to 2.0×10-5 mol/L (R2=0.9933). The detection limit (S/N=3) was 33 nmol/L.The proposed sensor had been successfully applied to the determination of 8-OHdG in human urine samples with high recovery rates.