Highly sensitive quantitative detection of carbendazim residue based on terahertz metamaterial enhancement and chemometrics

Objective Carbendazim is widely used as an effective fungicide in agriculture, but its residues on crops pose potential health risks to consumers. This study aims to develop a rapid, non-destructive, and highly sensitive method for detecting carbendazim residues. Methods Based on electromagnetic theory, this paper presented a terahertz metamaterial sensor incorporating a “cross” compound double-peak structure. Terahertz transmission spectra were collected from 21 different concentration gradients of carbendazim solutions. The spectral response showed a clear decreasing trend in transmission peak amplitude with increasing concentrations. By comparing the results of data preprocessing and feature extraction, the optimal model of terahertz metamaterial detection of carbendazim residue was established. Result The related coefficient of prediction set (R P ) and root mean square error of prediction set (RMSEP) of this model are 0.9825 and 0.2001, and the Limit of Detection (LOD) is 0.672 μg/mL. Conclusion The results demonstrate the feasibility of using terahertz metamaterial sensors combined with spectral analysis for high-sensitivity, non-destructive detection of carbendazim, offering a promising approach for food safety monitoring.