Simultaneous determination of naphthol isomers at poly(3-methylthiophene)-nano-Au modified electrode with the enhancement of surfactant.

A polymer film incorporated gold nanoparticle modified electrode was fabricated. The fabricated process involved eletrodeposition of gold nanoparticles and electropolymerization of the 3-methylthiophene (abbreviated 3MT) onto the glassy carbon electrode (GCE). The resulting electrode (P3MT-nano-Au/GCE) was characterized by scanning electron microscopy (SEM), and a simultaneous determination of naphthol isomers at P3MT-nano-Au/GCE was studied using semi-derivative voltammetry. Because of the synergistic effect of gold nanoparticles and poly(3MT), the sensitivity and distinguishability in the simultaneous determination of naphthol isomers were greatly increased. Besides, a further increase in the detecting sensitivity of naphthol isomers could be obtained in the presence of surfactant, cetyl trimethyl ammonium bromide (CTAB). Also, the role of different kinds of surfactants was texted and the action mechanism was discussed in detail. Under the optimal conditions, the linear calibration ranges of the determination of naphthols were 7.0×10(-7) to 1.5×10(-4) mol/L for 1-naphthol and 1.0×10(-6) to 1.5×10(-4) mol/L for 2-naphthol with detection limits of 1.0×10(-7) and 3.0×10(-7) mol/L (S/N=3), respectively.