“Coffee Ring” Fabrication and Its Application in Aflatoxin Detection Based on SERS
Xuesong Yan,
Wenfeng Zhu,
Yibing Wang,
Yiran Wang,
Dexuan Kong,
Min Li
Affiliations
Xuesong Yan
CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, Institute of High Energy Physics, The Chinese Academy of Sciences, Beijing 100049, China
Wenfeng Zhu
CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, Institute of High Energy Physics, The Chinese Academy of Sciences, Beijing 100049, China
Yibing Wang
School of Biotechnology, East China University of Science and Technology, Shanghai 200237, China
Yiran Wang
CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, Institute of High Energy Physics, The Chinese Academy of Sciences, Beijing 100049, China
Dexuan Kong
CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, Institute of High Energy Physics, The Chinese Academy of Sciences, Beijing 100049, China
Min Li
CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, Institute of High Energy Physics, The Chinese Academy of Sciences, Beijing 100049, China
The fabrication of a coffee ring was studied in this work to improve its sensitivity in detecting trace analytes based on surface-enhanced Raman scattering (SERS). Gold nanoparticles were synthesized with diameters of ~40 nm through the sodium citrate reduction method, and rhodamine 6G (R6G) was employed as a probe to evaluate the performance of the fabricated coffee rings. The results showed that the coffee ring formed from the water-washed gold nanoparticles presented more orderly and regular morphology as well as better SERS properties than the unwashed ones. Furthermore, both the concentration and the amount of gold nanoparticles were found to affect its SERS performance. Using the optimized coffee ring as a SERS substrate, trace R6G with a concentration of 5 × 10−8 M was detected. This sensing platform could realize aflatoxin B1 (AFB1) detection down to 5 × 10−7 M and was demonstrated to function well in real-sample testing.
