title: SiO2@Au nanoshells-based SERS method for detection of sunset yellow and chrysoidine.
abstract: A novel surface-enhanced Raman scattering (SERS) substrate made up of SiO2@Au nanoshells has been developed for detecting sunset yellow and chrysoidine. It exhibits an excellent enrichment SERS effect on these two colorant molecules. In this work, density functional theory (DFT) calculations have been carried out to determine the molecular structure and theoretical Raman spectra. This provided a good description of the characteristic peaks of the molecules. In addition, the appropriate thicknesses of the shell and environment pH have been derived to obtain improved SERS signals. The lowest concentration is 1 ppm and 0.5 ppm for sunset yellow and chrysoidine, respectively. Under optimal detection condition, it has proved possible to distinguish each colorant by its characteristic peaks in the SERS spectra of a mixture of the two colorants.
authors.affiliation: State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, China.
authors.forename: Yunfei
authors.initials: Y
authors.lastname: Xie
authors.affiliation: State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, China.
authors.forename: Yuliang
authors.initials: Y
authors.lastname: Cheng
authors.affiliation: State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, China.
authors.forename: Heya
authors.initials: H
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, China.
authors.forename: He
authors.initials: H
authors.lastname: Qian
authors.affiliation: State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, China. Electronic address: yaoweirongcn@jiangnan.edu.cn.
authors.forename: Weirong
authors.initials: W
authors.lastname: Yao
mesh_terms: D001391:Azo Compounds / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008958:Models, Molecular; D057145:Nanoshells / Q000737:chemistry* / Q000648:ultrastructure; D011789:Quantum Theory; D012822:Silicon Dioxide / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet; D013059:Spectrum Analysis, Raman; D014732:Vibration; D010128:p-Aminoazobenzene / Q000031:analogs & derivatives* / Q000737:chemistry
chemical_list: D001391:Azo Compounds; C005562:chrysoidine; D010128:p-Aminoazobenzene; D006046:Gold; D012822:Silicon Dioxide; C005842:6-hydroxy-5-((p- sulfophenyl)azo)-2-naphthalenesulfonic acid disodium salt
keywords: Chrysoidine; SiO(2)@Au; Sunset yellow; Surface-enhanced Raman scattering (SERS)