Method for detecting content of pesticide in cereal by utilizing terahertz time-domain spectroscopy

Abstract

The invention relates to a method for detecting the content of a pesticide in cereal by utilizing a terahertz time-domain spectroscopy. The method comprises the following steps of grinding and then tabletting a to-be-detected cereal sample to obtain a to-be-detected cereal tablet sample, testing the to-be-detected cereal tablet sample by directly adopting a terahertz time-domain spectroscopy system, acquiring a terahertz area spectrum signal to be used as a sample signal, acquiring a terahertz time-domain spectrum signal under a nitrogen atmosphere as a reference signal, acquiring an absorptive coefficient spectrum of the to-be-detected cereal tablet sample, acquiring a characteristic wave band of a target pesticide, classifying the absorptive coefficient spectrum of the to-be-detected cereal tablet sample to a corrected set of sample absorptive coefficient spectrum and a verification set of sample absorptive coefficient spectrum, establishing a quantitative analysis model by utilizing a partial least-squares regression method, and acquiring a quantitative detection value of each to-be-detected cereal sample. The method can truly and effectively detect the pesticide residue in the cereal quantitatively, rapidly and accurately, and the prediction square correlation coefficient (R2) of the quantitative analysis model reaches up to 0.9903.

Description

technical field [0001] The invention relates to a method for detecting pesticide content in grain by using terahertz time-domain spectroscopy technology, and belongs to the technical field of pesticide detection. Background technique [0002] With the rapid development of modern agriculture, the demand and dependence on pesticides for agriculture and agricultural products are increasing. Coupled with the fact that some practitioners lack pesticide knowledge, they have used pesticides in large quantities for a long time or even abused them, which has caused great impact and harm to the environment and human health. For crops, after pesticides are applied to crops, there will often be a small amount of residues in the crops. Long-term ingestion of residual pesticides will seriously affect human health, and will also cause major harm to the body and the ecological environment. Especially in recent years, teratogenic disability and poisoning incidents caused by excessive pestic...

AI Technical Summary

Problems solved by technology

Although the above method can realize the qualitative and quantitative detection of the antibiotic tetracycline hydrochloride in food, in the sample preparation process, the antibiotic tetracycline hydrochloride to be detected and high-density polyethylene powder are mixed and pressed into tablets, and polyethylene is used as the "background" Detect the content of antibiotics, so the final detection of this method is the relative value of the content of antibiotics in polyethylene, which leads to a far difference from the actual test sample, which affects the authenticity of the test sample; in addition, the introduction of new irrelevant The substance polyethylene will inevitably affect the accuracy of sample detection and waste medicine

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