Rapid detection method of nitrogen-containing pesticide residue based on infrared photoacoustic spectroscopy

Abstract

A detection method of residue a nitrogen-containing pesticide based on infrared photoacoustic spectroscopy is as follows: (1). collecting infrared photoacoustic spectroscopy data of a sample, to be more specific, using an infrared photoacoustic spectroscopy instrument, selecting appropriate parameters such as moving mirror speed and scanning times, and collecting the infrared photoacoustic spectral data of the sample; (2). performing pre-processing including wavelet analysis for smoothing and noise reduction, data normalization, and the like on the infrared photoacoustic spectral data obtainedin the step (1) to obtain an infrared photoacoustic spectral curve of the sample to be tested; (3). performing analysis including characteristic peak position identification and principal componentanalysis on the spectrogram obtained in the step (2); and (4). analyzing results, to be more specific, by combining the molecular structure of a pesticide, analyzing the spectrogram obtained in the step (3), and determining the position of an infrared absorption peak of a specific functional group in the molecular structure of the pesticide to be tested; and comparing the sample and contrasting that whether an infrared absorption peak occurs at the position, finally determining the type of the pesticide residue. The method can realize rapid, non-destructive and in-situ detection of agricultural products, and can be quickly developed into rapid on-site detection.

Description

Technical field [0001] The invention relates to the safety of agricultural products, belongs to the technical field of pesticide residue detection, and specifically relates to a method for quickly, non-destructively and accurately detecting nitrogen-containing pesticides in agricultural products by using mid-infrared photoacoustic spectroscopy. Background technique [0002] In the process of agricultural production, pesticides play an important role in the prevention and control of crop diseases and insect pests, and the use of pesticides brings huge benefits to agricultural production. But at the same time, due to the unreasonable use of pesticides, many environmental problems and food safety problems have been caused. Therefore, the research on the detection methods of pesticide residues is of great significance. [0003] At present, pesticide residue detection methods mainly rely on methods based on gas chromatography, liquid chromatography, and some chemical and biological met...

AI Technical Summary

Problems solved by technology

However, conventional infrared spectroscopy for the detection of pesticide residues cannot be applied at present

Conventional infrared transmission spectroscopy mainly includes transmission spectroscopy and reflection spectroscopy. Infrared transmission spectroscopy involves sample pretreatment, including homogenization and tableting processes. On the one hand, qualitative detection cannot be performed, and on the other hand, quantitative detection cannot be performed because the pesticide content is too low; The infrared reflectance spectrum is greatly affected by the environment and the shape of the sample, and at the same time, the small signal leads to large interference and instability, making it difficult to measure

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