Composites of thiol-grafted PEDOT with N-doped graphene or graphitic carbon nitride as an electrochemical sensor for the detection of paracetamol

A novel electrochemical sensor with thiol-grafted PEDOT/N-doped graphene (N-Gr/PEDOT-MeSH) and thiol-grafted PEDOT/graphitic carbon nitride (g-C3N4/PEDOT-MeSH) composites was fabricated for the detection of paracetamol (PAR). The formation mechanism of the obtained structure was thoroughly studied. And from the electrochemical results, the synergistic effect between the PEDOT-MeSH and g-C3N4 or N-Gr improved the electron transfer and conductivity of the modified electrodes and enhanced the sensing responses toward the electrochemical oxidation of PAR. The calibration curve of N-Gr/PEDOT-MeSH and g-C3N4/PEDOT-MeSH composites exhibited the wider linear responses for PAR, ranging from 2 to 1680 mu M and 0.4 to 1280 mu M, and the detection limits (S/N = 3) were 1.42 mu M and 1.0 mu M, respectively. Furthermore, the obtained composites exhibited the excellent reproducibility, lower detection limit and good stability. And it was capable of detecting PAR in real samples with a satisfying result.