Triazine-based COF/CNTs electrochemical sensor for simultaneous detection of sunset yellow and tartrazine in food samples

Abstract

In this study, we developed a novel electrochemical sensor by modifying a screen-printed carbon electrode (SPCE) with a triazine-based covalent organic framework (COF) and carbon nanotubes (CNTs), denoted as COF/CNTs/SPCE. This sensor enables the simultaneous detection of sunset yellow (SY) and tartrazine (Tz) with excellent sensitivity. Under optimized conditions, the COF/CNTs/SPCE exhibited efficient electron transfer kinetics and achieved low detection limits (S/N = 3) of 0.75 nM for SY and 7.5 nM for Tz, outperforming previously reported material-based electrochemical sensors. The sensor demonstrated high selectivity for SY and Tz even in the presence of various common interferents, along with good reproducibility and long-term stability. Moreover, the COF/CNTs/SPCE sensor was successfully applied to the quantitative analysis of multiple food samples, validating its practical applicability. These results underscore the potential of the COF/CNTs/SPCE as a high-performance, reliable platform for detecting synthetic food dyes in complex food matrices.