Modified with nanomaterial for potentiometric thiocyanate determination preparation of solid-contact electrodes

In this study, a new thiocyanate-selective solid-contact nanocomposite electrode was prepared by using dichlorobis(methyldiphenylphosphine) palladium(II) complex as ionophore. The optimum composition exhibiting the best performance characteristics of this electrode, constructed by adding some metal oxide nanoparticles to the carbon paste composition, was found as 11.6 % graphite powder, 34.8 % ionophore, 13.0 % o-nitrophenyl octylether (o-NPOE), 31.9 % tetraheptylammonium tetraphenylborate (THATFB) and 8.7 % cobalt oxide nanoparticles (Co3O4 NP). The linear range, slope, lifetime, detection limit, and the response time of the nanocomposite electrode are 1.0×10-1 – 1.0×10-6 M, 59.7±0.6 mV/pSCN, at least 2 months, 1.4×10-8 M and 5 s, respectively. Furthermore, the order of the selectivity coefficients calculated by the separate solution method in the presence of other anions at pH 4.0 was found as carbonate> salicylate> perchlorate> iodide> chloride> nitrate> nitrite> sulfite> bromide> acetate> fluoride. It was shown to be a well-functioning indicator electrode for the quantification of thiocyanate in a veterinary drug sample.