Highly sensitive SERS substrates with multi-hot spots for on-site detection of pesticide residues

Tianhua Xie; Zijin Cao; Yuejing Li; Zhiyan Li; Fan-Li Zhang; Yingqiu Gu; Caiqin Han; Guohai Yang; Lulu Qu

doi:10.1016/j.foodchem.2022.132208

Highly sensitive SERS substrates with multi-hot spots for on-site detection of pesticide residues

Food Chem. 2022 Jul 1:381:132208. doi: 10.1016/j.foodchem.2022.132208. Epub 2022 Jan 21.

Authors

Tianhua Xie¹, Zijin Cao², Yuejing Li¹, Zhiyan Li¹, Fan-Li Zhang³, Yingqiu Gu¹, Caiqin Han⁴, Guohai Yang¹, Lulu Qu⁵

Affiliations

¹ School of Chemistry & Materials Science, Jiangsu Normal University, Xuzhou 221116, China.
² Jiangsu Key Laboratory of Advanced Laser Materials and Devices, School of Physics and Electronic Engineering, Jiangsu Normal University, Xuzhou, Jiangsu 221116, China.
³ College of Optical and Electronic Technology, China Jiliang University, Hangzhou 310018, China. Electronic address: zhangli_fan@126.com.
⁴ Jiangsu Key Laboratory of Advanced Laser Materials and Devices, School of Physics and Electronic Engineering, Jiangsu Normal University, Xuzhou, Jiangsu 221116, China. Electronic address: hancq@jsnu.edu.cn.
⁵ School of Chemistry & Materials Science, Jiangsu Normal University, Xuzhou 221116, China. Electronic address: luluqu@jsnu.edu.cn.

PMID: 35123223
DOI: 10.1016/j.foodchem.2022.132208

Abstract

Pesticide residues will be a huge threat to food security and ecological environment; therefore, there is an urgent need to achieve rapid and on-site detection of pesticide residues. Herein, a plasmonic substrate with multiple "hot spots" was fabricated by transferring three-dimensional (3D) Au nanoparticles (NPs) onto the polydimethylsiloxane (PDMS) membrane for highly sensitive surface-enhanced Raman scattering (SERS) detection of pesticide residues. In combination with 3D-FDTD simulations, high SERS enhancement (EF = 1.2 × 10⁸) and high detection sensitivity (LOD = 6.3 × 10^-10 M) were achieved, mainly due to the enhanced electromagnetic fields around the "hot spots". Additionally, the PDMS-based SERS substrate held good transparency and flexibility, enabling conformal contact with non-planar surfaces and allowing the laser to penetrate the back of the analytes. Combined with a portable Raman spectrometer, the substrates holds great potential for rapid, high-sensitive, and on-site detection of contaminants in food, especially for the analyte on the nonplanar surfaces.

Keywords: Hot spots; On-site detection; Pesticide residues; Plasmonic nanostructure.

MeSH terms

Gold / chemistry
Metal Nanoparticles* / chemistry
Pesticide Residues* / analysis
Spectrum Analysis, Raman / methods

Substances

Pesticide Residues
Gold