Detection of melamine by using carboxyl-functionalized Ag-COF as a novel SERS substrate

Zichen Yang; Chaoqun Ma; Jiao Gu; Yamin Wu; Chun Zhu; Lei Li; Hui Gao; Wenzhi Yin; Zirui Wang; Guoqing Chen

doi:10.1016/j.foodchem.2022.134078

Detection of melamine by using carboxyl-functionalized Ag-COF as a novel SERS substrate

Food Chem. 2023 Feb 1:401:134078. doi: 10.1016/j.foodchem.2022.134078. Epub 2022 Sep 3.

Authors

Zichen Yang¹, Chaoqun Ma², Jiao Gu², Yamin Wu², Chun Zhu², Lei Li², Hui Gao², Wenzhi Yin¹, Zirui Wang², Guoqing Chen³

Affiliations

¹ School of Science, Jiangnan University, Wuxi, China; School of Internet of Things Engineering, Jiangnan University, Wuxi, China; Jiangsu Provincial Research Center of Light Industrial Optoelectronic Engineering and Technology, Wuxi, China.
² School of Science, Jiangnan University, Wuxi, China; Jiangsu Provincial Research Center of Light Industrial Optoelectronic Engineering and Technology, Wuxi, China.
³ School of Science, Jiangnan University, Wuxi, China; Jiangsu Provincial Research Center of Light Industrial Optoelectronic Engineering and Technology, Wuxi, China. Electronic address: jncgq@jiangnan.edu.cn.

PMID: 36113215
DOI: 10.1016/j.foodchem.2022.134078

Abstract

Melamine, a nitrogen-containing organic molecule, has received widespread attention as it had been illegally added in dairy products to increase the content of nitrogen, leading to kidney stones in healthy people after long-term ingestion. Based on SERS technology and Covalent Organic Framework (COF) materials, we developed carboxyl-functionalized Ag-COF-COOH materials as SERS substrates for the detection of melamine adulteration. Using COF material as a ligand can effectively reduce the influence of interferents in milk. In addition, we investigated two causes of melamine SERS enhancement: the ordered arrangement of Ag NPs and the strong interaction between the substrate and the melamine. The linear range was 1-20 μg/L and the limit of detection (LOD) was 0.68 μg/L in liquid milk due to the high sensitivity and reliability of this method. The results show that this new SERS substrate has great potential for applications in the food surveillance industry.

Keywords: Covalent organic frameworks (COFs); Melamine; Surface-enhanced Raman scattering (SERS).

MeSH terms

Humans
Ligands
Metal-Organic Frameworks*
Nitrogen
Reproducibility of Results
Spectrum Analysis, Raman* / methods

Substances

melamine
Metal-Organic Frameworks
Ligands
Nitrogen