Simultaneous voltammetric determination of dihydroxybenzene isomers at single-walled carbon nanohorn modified glassy carbon electrode

The voltammetric behaviors of dihydroxybenzene isomers were studied at the single-walled carbon nanohorn modified glassy carbon (SWCNH-modified GC) electrode. Compared with the bare electrode, SWCNH-modified GC electrode has stronger electrocatalytic activity for the oxidation of dihydroxybenzenes with the increase in peak current and the decrease in peak separation (Delta E-p) between the anodic and cathodic peaks. Furthermore, the three isomers can be determined simultaneously and sensitively by using linear sweep voltammetry at the SWCNH-modified GC electrode. For hydroquinone, catechol, and resorcinol, the oxidation peak currents are linear with the concentrations in the range of 0.5-100 mu M, 0.5-100 mu M, and 1.0-100 mu M, respectively. Their detection limits at a signal-to-noise ratio of 3 are 0.1 mu M, 0.2 mu M, and 0.5 mu M, respectively. These results make SWCNH-modified GC electrode a promising candidate for the simultaneous determination of isomers. (C) 2014 Elsevier B.V. All rights reserved