Research on highly sensitive detection of clenbuterol hydrochloride based on THz metamaterial enhancement

The abuse of clenbuterol hydrochloride (CL) is a serious threat to people’s life and health. The traditional THz detection method can only detect the sample at the milligram level, which is not suitable for trace analysis of the sample. In this paper, a THz metamaterial enhanced micro-nano structure was designed based on the electromagnetic theory to realize the highly sensitive detection of the trace CL by THz spectroscopy. Firstly, four pretreatment methods were used to correct the spectrum, including AirPLS, AsLS, Backcor and BEADS. Secondly, four algorithms, namely, PCA, CARS, UVE, and SPA were used to extract features from the spectra. Finally, the PLS and LS-SVM models are established. The AirPLS-CARS-LS-SVM model has the best result, with the R p of 0.9743, the RMSEP of 2.90 × 10 –5 , and the LOD of 9.67 × 10 –5 mg/mL. This study will facilitate the rapid, nondestructive and highly sensitive detection of the trace CL in food. Besides, this study has significant implications for promoting the detection of other types of clenbuterol and trace substances. Graphical abstract