title: Smart liquid SERS substrates based on Fe3O4/Au nanoparticles with reversibly tunable enhancement factor for practical quantitative detection.
abstract: There is a strong correlation between the surface enhanced Raman scattering (SERS) enhancement factor (EF), the excitation wavelength, and the feature properties (composition, size, geometry, and analytes). The prediction of the EF of specific substrates, crucial to the quantitative SERS detection, is however still very difficult. The present work presents smart liquid SERS substrates consisting of suspensions of Fe3O4/Au nanoparticles, which provide high spot-to-spot uniformity, reproducibility and good reversibility. The EF of these substrates can be reversibly tuned by applying an external magnetic field. The EF magnetic tuning is within 2 orders of magnitude per substrate in the range of 10(4)-10(7). The ability to reversibly adjust the SERS EF enables to reduce EF variations caused by external effects such as substrate-to-substrate differences and long-term-storage degradation. This improves the quantitative detection of analytes and might be a significant step forward in employing SERS for practical applications.
authors.affiliation: Institute of Functional Nano &Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-based Functional Materials and Devices &Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215123, P. R. China.
authors.forename: Fei
authors.initials: F
authors.lastname: Hu
authors.affiliation: Institute of Functional Nano &Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-based Functional Materials and Devices &Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215123, P. R. China.
authors.forename: Haiyang
authors.initials: H
authors.lastname: Lin
authors.affiliation: Institute of Functional Nano &Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-based Functional Materials and Devices &Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215123, P. R. China.
authors.forename: Zhaoshun
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Institute of Functional Nano &Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-based Functional Materials and Devices &Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215123, P. R. China.
authors.forename: Fan
authors.initials: F
authors.lastname: Liao
authors.affiliation: Institute of Functional Nano &Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-based Functional Materials and Devices &Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215123, P. R. China.
authors.forename: Mingwang
authors.initials: M
authors.lastname: Shao
authors.affiliation: 1] Institute of Functional Nano &Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-based Functional Materials and Devices &Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215123, P. R. China [2] Materials Science and Engineering Department, Technion, Israel Institute of Technology, Haifa 32000, Israel.
authors.forename: Yeshayahu
authors.initials: Y
authors.lastname: Lifshitz
authors.affiliation: Institute of Functional Nano &Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-based Functional Materials and Devices &Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215123, P. R. China.
authors.forename: Shuit-Tong
authors.initials: ST
authors.lastname: Lee