Fabrication of a nickel titanate nanoceramic modified electrode for electrochemical studies and detection of salicylic acid

The aim of this research is preparation of a nanoceramic modified sensor for electrochemical studies and determination of salicylic acid (SA). At first, the sol-gel method was used for synthesizing of nickel titanate (NiTiO3) nanoceramics. The characterization of the nanoceramics was studied by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Then, the nanoparticles were used for fabrication of a carbon paste modified electrode. The structure of the modified electrode was studied by SEM and cyclic voltammetry (CV). Electrochemical studies of SA were performed by various techniques such as CV, chronoamperometry, chronocoulometry, linear sweep voltammetry (LSV) and differential pulse voltammetry (DPV). For achieving the best sensitivity, multivariate optimization was used based on rotatable central composite design (RCCD) and response surface methodology (RSM). Under the optimized conditions, two linear calibration ranges of 3.0-40.0 mu M and 40.0-1000.0 mu M, for SA were obtained with the detection limit of 68.0 nM (S/N = 3). Finally the NiTiO3 nanopowder modified carbon paste electrode (NiTiO3/CPE) could be employed for the determination of SA in real samples with satisfactory results. (C) 2015 Elsevier B.V. All rights reserved.