Chemometrics-assisted determination of Sudan dyes using zinc oxide nanoparticle-based electrochemical sensor

Multivariate curve resolution-alternating least squares (MCR-ALS) assisted with electrochemical techniques was applied for simultaneous determination of Sudan II and III at a surface of zinc oxide nanoparticles (ZnONPs) modified carbon paste electrode. Characterization of the ZnONPs and the nanostructured modified electrode was performed by X-ray diffraction (XRD), scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) techniques. Response surface methodology using central composite rotatable design was employed to design of experiments and achieving to optimum values of variables. For simultaneous determination of Sudan II and III, electrochemical second order data were obtained by changing of pulse height in differential pulse voltammetry technique. MCR-ALS was performed on the data to obtain the decomposition peaks of analytes. Then, the detection limits were obtained 1.87 and 2.62 nM for Sudan II and III, respectively. Finally, this method used for the analysis of the two analytes in real samples.