| Abstract: | Abstract Nano-MnO2/chitosan composite film modified glassy carbon electrode (MnO2/CHIT/GCE) was fabricated and a DNA probe was immobilized on the electrode surface. The immobilization and hybridization events of DNA were characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The EIS was applied to the label-free detection of the target DNA. The human immunodeficiency virus (HIV) gene fragment was successfully detected by this DNA electrochemical sensor. The dynamic detection range was from 2.0 × 10?11 to 2.0 × 10?6 mol/L, with a detection limit of 1.0 × 10?12 mol/L. |
