Au-NP-Decorated Cotton Swabs as a Facile SERS Substrate for Food-Safety-Related Molecule Detection

Farzana Rafiq; Ning Wang; Keyou Li; Zijin Hong; Dandan Cao; Jingjing Du; Zhenli Sun

doi:10.1021/acsomega.2c07690

Au-NP-Decorated Cotton Swabs as a Facile SERS Substrate for Food-Safety-Related Molecule Detection

ACS Omega. 2023 Feb 23;8(9):8541-8547. doi: 10.1021/acsomega.2c07690. eCollection 2023 Mar 7.

Authors

Farzana Rafiq¹, Ning Wang¹, Keyou Li¹, Zijin Hong¹, Dandan Cao¹, Jingjing Du², Zhenli Sun¹

Affiliations

¹ MOE Key Laboratory of Resources and Environmental System Optimization, College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, China.
² State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.

Abstract

Recently, food safety has received considerable attention, and various analytical techniques have been employed to monitor food quality. One of the promising techniques in this domain is the surface-enhanced Raman scattering (SERS) technique. This study developed a facile, cost-effective SERS method by supporting a wipe-type substrate with a small-head cotton swab. We fabricated Au-nanoparticle (NP)-decorated cotton swabs (CS-Au NP) via the dropwise addition of gold colloid on the cotton fibers. These swabs exhibit reduced gold colloid consumption and a compact fiber structure, allowing for the uniform distribution of Au NPs and easy capture of molecular signals. Experiments were conducted to obtain a CS-Au NP wiper performance optimized for cotton swab selection, NaCl concentration, and Au NP layers. The Raman reporter molecule 4-mercaptopyridine was detected at a concentration of 1 × 10^-8 M and a relative standard deviation of ≤10%. The proposed SERS platform enables the facile and reliable detection of food-safety-related molecules such as malachite green on the surface of fruits and vegetables. This paper describes the development of an easy, cost-effective, and environment-friendly method of detecting food-safety-related molecules on various food surfaces through SERS.