A Feasible Approach to Detect Pesticides in Food Samples Using THz-FDS and Chemometrics

Abstract

The use of pesticides will have an impact on food, organisms, and environment. Specifically, pesticide residues in food will damage human health. Because of its high permeability, low energy, high spectral resolution, and fingerprint characteristics, terahertz frequency-domain spectroscopy has been introduced into the determination of pesticides (imidacloprid, acetamiprid, and triadimefon) residues in food samples (glutinous rice flour, wheat flour, and corn flour) in our present study. These three pesticides exhibit their own absorption peaks in the region of 0.4–1.7 THz. For understanding the origins of these peaks, the experimental data are interpreted by using density functional theory calculations at the level of B3LYP/6-31G (d). It is found that these absorption peaks come from the intramolecular and intermolecular interactions. The absorption peaks of pesticides are still detectable in a mixture of pesticides and food samples when they reach a certain concentration. The results from chemometrics analysis show that quantitative detection of pesticides in food samples is feasible. The partial least squares regression models have high correlation coefficient (>0.99), low root-mean-square error of calibration (<1.5%), low root-mean-square error of cross-validation (<2.4%), and low root-mean-square error of prediction (<2.3%), indicating good quality of prediction for pesticides concentration. Our results prove that the terahertz frequency-domain spectrum combined with chemometrics can be used for the detection of pesticides in food samples.

Moxa Wool in Different Purities and Different Growing Years Measured by Terahertz Spectroscopy

“…Because of its high precision and low computational complexity, the DFT plays a significant role in the analysis of molecular structure [ 28 ]. Using Gauss -09 package (revised version D.01, American Gauss Company) together with B3LYP hybridization function and 6-31G basis set, we calculated the absorption peak position of terpineol at THz frequency [ 29 ].…”

Nondestructive testing methods for pesticide residue in food commodities: A review

“…THz radiation has potential uses in chemistry, biochemistry, pharmacology, microelectronics, and agriculture (Chen et al., 2020; Qin et al., 2013). In the realm of biochemistry, THz spectroscopy coupled with chemometrics has been more popular in recent years for qualitative and quantitative detection (Chen et al., 2020).…”

“…THz‐FDS is based upon photon mixing technology and can give greater frequency resolution across a wider spectrum range than THz‐TDS. Furthermore, the spectrum information of the sample can be retrieved without the need for the Fourier transform, as in the case of THz‐TDS (Chen et al., 2020). Table 3 summarizes the details of THz spectroscopy for pesticide detection in food commodities.…”

“…In a recent study, Chen et al. (2020) developed a method using THz‐FDS and chemometrics for qualitative identification and quantitative analysis of pesticides, namely, imidacloprid, acetamiprid, and triadimefon in food samples. PLS regression models showed a high correlation coefficient (>.99), a low root‐mean‐square error of calibration (1.5%), a low root‐mean‐square error of cross‐validation (2.4%), and a low root‐mean‐square error of prediction (2.3%), indicating good accuracy in pesticide concentration prediction.…”

A Novel Method for Carbendazim High-Sensitivity Detection Based on the Combination of Metamaterial Sensor and Machine Learning

“…Thus, THz–TDS is regarded as a promising chemical and biological substance detection method [ 21 , 22 , 23 , 24 ]. In the field of pesticide detection, the pesticides imidacloprid, acetamiprid, triadimefon, carbendazim, thiamethoxam, and thiabendazole have been inspected by THz–TDS [ 25 , 26 , 27 , 28 , 29 ]. Nevertheless, the limited sensitivity prohibits THz–TDS from being widely used in pesticide detection.…”