Electrochemical behavior of thiosalicylic acid at γ-Fe2O3 nanoparticles and clay composite carbon electrode

In the current work, the fabricated novel electrode achieved an enhanced sensitivity and electrocatalytic behavior towards thiosalicylic acid (TSA) detection, by coating gamma-Fe2O3 nanoparticles and bentonite clay composite on the carbon paste matrix. The surface characteristics of modifier were studied by utilizing scanning electron microscope (SEM) and X-ray diffractometer (XRD) followed by atomic force microscopy (AFM). The electrooxidation of TSA was studied at gamma-Fe2O3-CPE, clay-CPE and gamma-Fe2O3/clay-CPE by cyclic voltammetry (CV) and square wave voltammetric (SWV) techniques. The gamma-Fe2O3/clay-CPE sensitivity for TSA has shown significant augmentation compared to the other electrodes. In addition, the modified electrode processes some unique characteristics, such as appropriate charge transfer rate, enduring stability, exceptional reproducibility and antifouling effects. The parameters affecting the peak enhancement such as pH, modifier amount, accumulation time, scan rate and concentration impacts were studied. The concentration of TSA was determined by the electrode in a wide concentration range of about 0.05 mu M-0.5 mu M with LOD value of 5.7 nM. The practical electroanalytical application was conducted by carrying out quantification of TSA in human urine samples. (C) 2018 Elsevier Ltd. All rights reserved.