A molecularly-imprinted SERS sensor based on a TiO2@Ag substrate for the selective capture and sensitive detection of tryptamine in foods

Chen Chen; Ximo Wang; Yingfang Zhang; Xingying Li; Huiju Gao; Geoffrey I N Waterhouse; Xuguang Qiao; Zhixiang Xu

doi:10.1016/j.foodchem.2022.133536

A molecularly-imprinted SERS sensor based on a TiO₂@Ag substrate for the selective capture and sensitive detection of tryptamine in foods

Food Chem. 2022 Nov 15:394:133536. doi: 10.1016/j.foodchem.2022.133536. Epub 2022 Jun 21.

Authors

Chen Chen¹, Ximo Wang¹, Yingfang Zhang¹, Xingying Li¹, Huiju Gao², Geoffrey I N Waterhouse³, Xuguang Qiao¹, Zhixiang Xu⁴

Affiliations

¹ Key Laboratory of Food Processing Technology and Quality Control in Shandong Province, College of Food Science and Engineering, Shandong Agricultural University, Tai'an 271018, People's Republic of China.
² College of Forestry, Shandong Agricultural University, Tai'an 271018, People's Republic of China.
³ School of Chemical Sciences, The University of Auckland, Auckland 1142, New Zealand. Electronic address: g.waterhouse@auckland.ac.nz.
⁴ Key Laboratory of Food Processing Technology and Quality Control in Shandong Province, College of Food Science and Engineering, Shandong Agricultural University, Tai'an 271018, People's Republic of China. Electronic address: zhixiangxu@sina.com.

PMID: 35753253
DOI: 10.1016/j.foodchem.2022.133536

Abstract

Herein, a molecularly imprinted surface-enhanced Raman spectroscopy (SERS) sensor was developed for the selective capture and sensitive detection of tryptamine in foods. The SERS sensor exploited silver nanoparticle-decorated TiO₂ (TiO₂@Ag) substrates for Raman signal enhancement via synergistic effect of electromagnetic enhancement and photoinduced charge-transfer, whilst surface functionalization with the molecularly imprinted polymer ensured selective tryptamine capture. The SERS spectrum of tryptamine on the sensor closely matched that predicted by density functional simulations. The SERS intensity for tryptamine on the developed TiO₂@Ag@MIP sensor increased linearly with the logarithm of the tryptamine concentration over the range of 10^-6-10^-2 mol L^-1, with a LOD of 4.85 × 10^-7 mol L^-1. Tryptamine was detected in a spiked white vinegar sample, and its recoveries were in the range of 92.00%-111.40%. The SERS sensor could be used for the detection of tryptamine in actual samples.

Keywords: Molecularly imprinted polymer; SERS; Sensor; Tryptamine.

MeSH terms

Limit of Detection
Metal Nanoparticles* / chemistry
Silver* / chemistry
Spectrum Analysis, Raman / methods
Titanium
Tryptamines

Substances

Tryptamines
titanium dioxide
Silver
Titanium