Electrochemical Sensor Based on MWCNTs/AuNPs/GCE for Sensitive Determination of Sudan I Content in Food Samples
Liu Yang, Shunyu Wang, Lu Zhang
Abstract
In this work, the electrochemical properties of MWCNTs/AuNPs/GCE were studied for the determination of Sudan I. The GCE surface was modified through electrodeposited AuNPs and spray pyrolysis synthesized MWCNTs. The morphology and structure of synthesized AuNPs and MWCNTs were studied by FESEM and XRD analyses. The cycle voltammetry and amperometry techniques were applied to study the electrochemical properties of MWCNTs/AuNPs/GCE. Results showed the high density and porous structure of MWCNTs and AuNPs were modified GCE surfaces. The electrochemical studies displayed that MWCNTs/AuNPs/GCE had high stability and sensitivity (6.8028 μA/mM), wide linear range (10–260 μM) and low detection limit (4 nM) for the determination of Sudan I. Comparison of MWCNTs/AuNPs/GCE with the other reported electrochemical sensors showed that the modification of sensor with MWCNTs and AuNPs were meaningfully promote the sensitivity, detection limit and linear range of electrode for the determination of Sudan I. Study of the selectivity and interference response of modified sensor in the presence of Ca 2+ , Mg 2+ , Al 3+ , Na + , Fe 3+ , Zn 2+ , beta-carotene, lycopene, lutein, cryptoxanthin and capsanthin as natural pigments displayed that the modified electrode did not show any significant response for the injections of these analytes. Response of modified electrode for the determination of Sudan I in real samples was evaluated.