ZIF-8-doped Au/PEDOT nanocomposite as an effective electrochemical sensing platform for simultaneous detection of catechin and sunset yellow in tea beverage

Abstract

Abstract In this paper, a novel composite based on gold nanoparticles (Au NPs), poly(3,4-ethylenedioxythiophene) (PEDOT), and ZIF-8 has been prepared through the hydrothermal method and used as a promising electrochemical sensing platform for simultaneously detect the catechin (CA) and sunset yellow (SY). In the Au/PEDOT/ZIF-8 composite, PEDOT can not only conduct electricity but also fix Au NPs to boost the sensing performance, and ZIF-8 is added to improve the overall structural properties of the composite. Under optimized conditions, the dual-detection system of this proposed electrochemical sensing platform demonstrated excellent performance for simultaneous detection of CA and SY, with a low limit of detection (LOD, S/N = 3) of 0.1 µM for CA in the linear range of 0.3 ~ 1 µM (R2 = 0.9986) and 1 ~ 50 µM (R2 = 0.9975), the LOD of 1 µM for SY in the range of 3 ~ 25 µM (R2 = 0.9964), respectively. In addition, Au/PEODT/ZIF-8 sensing platform has been successfully applied to simultaneously detect CA and SY in tea drink, indicating the promising application prospect of the Au/PEDOT/ZIF-8 sensing platform in food safety for rapid and field detection.