An enzymatic amplified system for the detection of 2,4-dichlorophenol based on graphene membrane modified electrode

摘要

A novel biosensor containing horseradish peroxidase (HRP) and graphene for the detection of 2,4-dichlorophenol (2,4-DCP) is described. The radicals, formed during the enzymatic oxidation of 2,4-DCP in the presence of H2O2, were reduced electrochemically on the electrode. The reduction current was proportional to the concentration of 2,4-DCP in the solution. The effects of HRP concentration, pH, applied potential and H2O2 concentration on the analytical performances of the biosensor are investigated. Under the optimal conditions, the proposed biosensor exhibited a wide linearity for 2,4-DCP detection from 1.0 ?— 10a?’8 M to 1.3 ?— 10a?’5 M, and the detection limit was down to 5.0 ?— 10a?’9 M (S/N = 3). In comparison with the reported 2,4-DCP sensors, this proposed biosensor exhibits wide linearity and low detection limit. Moreover, it also has good reproducibility and long-term stability.