Method for detecting pesticide content in grain by using terahertz frequency band infrared spectroscopy

Abstract

The invention relates to a method for utilizing terahertz band infrared spectrum technology to detect the content of pesticides in foodstuffs. Foodstuff samples to be tested are grinded and pressed to obtain to-be-tested foodstuff sample sheets; the to-be-tested foodstuff sample sheets are tested by directly adopting a terahertz frequency band FTIR system, and a terahertz regional spectrum is obtained and used as a sample spectrum; under the same condition, the terahertz regional spectrum in a vacuum state is used as a reference spectrum, further an absorption coefficient spectrum of the foodstuff sample sheets to be tested is obtained, and the characteristic wave band of a target pesticide is acquired; finally, the absorption coefficient spectrum of the to-be-tested foodstuff sheets is divided into a calibration set sample absorption spectrum and a verification set sample absorption spectrum, a quantitative analysis model is constructed by using a support vector machine (SVM) regression method, and the quantitative detection values of various to-be-tested foodstuff samples are obtained. The method can really and effectively perform quick and accurate quantitative detection of residual pesticide in the foodstuffs, and the average value of the prediction correlation coefficient (Rv) of the quantitative analysis mode is up to 0.9796.

Description

technical field [0001] The invention relates to a method for detecting pesticide content in grain by using terahertz frequency band Fourier transform infrared 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 incide...

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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