A modified electrode based on a 3D reduced graphene oxide and MoS₂ composite for simultaneous detection of sunset...

A 3D reduced graphene oxide (3DrGO) composite loaded with cauliflower-like MoS₂ was prepared. Benefiting from the synergistic effects of 3DrGO and cauliflower-like MoS₂, a glassy carbon electrode (GCE) modified with the 3DrGO-MoS₂ composite (3DrGO-MoS₂/GCE) displays high sensing performance for sunset yellow (SY) and tartrazine (TZ) at working potentials of 0.795 and 1.034 V. Furthermore, a well separated oxidation peak potential can achieve simultaneous detection of the two analytes. Under selected conditions, the peak current exhibits a piecewise linear relationship with the SY concentration in the range of 0.05-10 μmol L^-1 and 10-60 μmol L^-1, and the plot of peak current versus the TZ concentration also exhibits two linear segments in the range of 0.1-6.0 μmol L^-1 and 6.0-60 μmol L^-1. The detection limits of SY and TZ are as low as 17.6 and 37.4 nmol L^-1, respectively. The prepared 3DrGO-MoS₂/GCE was applied for the determination of SY and TZ in food samples with excellent recoveries of 95.1-105.4%.