NiO nanoparticles modified carbon paste electrode as a novel sulfasalazine sensor

• Published in: Analytica chimica acta Vol. 1031; pp. 47 - 59
• Main Authors: Amani-Beni, Zahra, Nezamzadeh-Ejhieh, Alireza
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 15-11-2018; Elsevier BV
• Subjects: Calibration; Carbon; Carbon paste electrode; Charge transfer; Electrochemical impedance spectroscopy; Electrochemical sensor; Electrochemistry; Electrodes; Electrons; Jahn-Teller effect; Nanoparticles; Nickel oxides; NiO nanoparticles; Oxidation; Oxidation process; Response surface methodology; Roasting; RSM; Sensors; Sodium hydroxide; Sol-gel processes; Spectroscopy; Sulfasalazine; Sulfasalazine; NiO nanoparticles; Electrochemical sensor; Carbon paste electrode; RSM
• ISSN: 0003-2670; 1873-4324
• DOI: 10.1016/j.aca.2018.06.002

The sol-gel synthesized NiO nanoparticles were characterized and used for the modification of a carbon paste electrode (CPE) in electrocatalytic voltammetric determination of sulfasalazine. Calcination temperature of NiO had an important role on the peak current of the modified NiO-CPE and calcined NiO at 200 °C had the best and maximum peak current for the corresponding electrode. Jahn-Teller and a Z-out effects for the singlet electrons in their 3dz2 orbital for calcined NiO at 200 °C relatively instable such electrons and hence they can easily participate in the electro-oxidation process. The electrochemical impedance spectroscopy (EIS) results confirmed that the modified CPE by calcined NiO at 200 °C has lower charge transfer resistance. In interaction effects study between the experimental variables by using the response surface methodology (RSM) approach, the optimized run included the 17.5% of NiO modifier, 0.5 M NaOH, amplitude of 295 mV, step potential of 7 mV and frequency of 15 Hz. A calibration plot in the range of 0.009–1.6 μM with limits of detection (LOD) and quantification (LOQ) of 0.002 and 0.006 μM was obtained, respectively. The modified electrode showed good selectivity and applicability for SSZ determination in complex matrixes.
Effect of calcination temperature of NiO on the voltammetric response of the modified NiO-CPE electrodes in NaOH supporting electrolyte at 1 M NaOH supporting electrolyte, ν = 50 mV s−1, 20% modifier. [Display omitted]
•Good activity of NiO-CPE for indirect voltammetric determination of SSZ.•Needing strong basic pH > 13 for electro-oxidation of NiO to NiOOH.•Significant dependence of calcinations temperature of NiO on the peak current of NiO-CPE electrode.•Increase in oxidation peak current of NiO electro-oxidation in the presence of SSZ.