Simultaneous determination of dihydroxybenzene isomers based on thionine functionalized multiwall carbon nanotubes modified electrode

In this article, simultaneous determination of dihydroxybenzene isomers [hydroquinone (HQ), catechol (CC), and resorcinol (RC)] was investigated using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) at thionine functionalized multiwalled carbon nanotube (TH-MWCNTs) modified glass carbon electrode. CV and DPV results showed that the TH-MWCNTs modified electrode exhibited excellent recognition ability toward the three isomers of dihydroxybenzene. Their oxidize peak currents were linear over ranges from 9.0 × 10−7 to 3.6 × 10−4 M for HQ, from 3.3 × 10−6 to 8.1 × 10−4 M for CC and from 4.3 × 10−6 to 9.0 × 10−4 M for RC, with the detection limits of 2.7 × 10−7, 1.0 × 10−6, and 1.1 × 10−6 M, respectively. The proposed method would potentially be applied to multi-component analysis in environmental control and chemical industry.