Raman silent region - based method for detection of pesticides with cyano group

Shuna Mi; Chang Xu; Qingrun Liu; Yuhang Du; Shaofeng Yuan; Hang Yu; Yahui Guo; Yuliang Cheng; Yunfei Xie; Weirong Yao

doi:10.1016/j.saa.2024.124326

Raman silent region - based method for detection of pesticides with cyano group

Spectrochim Acta A Mol Biomol Spectrosc. 2024 Apr 23:316:124326. doi: 10.1016/j.saa.2024.124326. Online ahead of print.

Authors

Shuna Mi¹, Chang Xu², Qingrun Liu¹, Yuhang Du¹, Shaofeng Yuan¹, Hang Yu¹, Yahui Guo¹, Yuliang Cheng¹, Yunfei Xie¹, Weirong Yao³

Affiliations

¹ State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu Province, China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu Province, China; Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, Jiangnan University, China.
² China Academy of Launch Vehicle Technology, Beijing, China.
³ State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu Province, China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu Province, China; Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, Jiangnan University, China. Electronic address: yaoweirongcn@jiangnan.edu.cn.

PMID: 38669978
DOI: 10.1016/j.saa.2024.124326

Abstract

Based on the fact that not all chemical substances possess good Raman signals, this article focuses on the Raman silent region signals of pesticides with cyano group. Under the optimized conditions of methanol-water (1:1, v/v) as the solvent, irradiation at 302 nm light source for 20 min, and the use of 0.5 mol/L KI as the aggregating agent, Surface-enhanced Raman spectroscopy (SERS) method for azoxystrobin detection was developed by the Raman silent region signal of 2230 cm^-1, and verified by detecting the spiked grapes with different concentrations of azoxystrobin. Other four pesticides with cyano group also could be identified at the peak of 2180 cm^-1, 2205 cm^-1, 2125 cm^-1, and 2130 cm^-1 for acetamiprid, phoxim, thiacloprid and cymoxanil, respectively. When azoxystrobin or acetamiprid was mixed respectively with chlorpyrifos without cyano group, their SERS signals in the Raman silent region of chlorpyrifos were not interfered, while mixed with cymoxanil in different ratios (1:4, 1:1 and 4:1), respectively, each two pesticides with cyano group could be distinguished by the changes in the Raman silent region. In further, four pesticides with or without cyano group were mixed together in 1:1:1:1 (acetamiprid, cymoxanil, azoxystrobin chlorpyrifos), and each pesticide still could be identified even at 0.5 mg/L. The results showed that the SERS method combined with UV irradiation may provide a new way to monitor the pesticides with C≡N performance in the Raman silent region without interference from the food matrix.

Keywords: Azoxystrobin; C≡N; Pesticides; SERS; UV irradiation.