title: A hanging plasmonic droplet: three-dimensional SERS hotspots for a highly sensitive multiplex detection of amino acids.
abstract: A novel and simple platform for an efficient SERS detection was demonstrated in a hanging plasmonic droplet of Ag sols by virtue of three-dimensional (3D) SERS hotspots. The platform was a single droplet of concentrated Ag sols with analytes hung on a hydrophobically treated transparent cover glass. Liquid adhesive force, solvent evaporation, and hydrophobic interaction induced a concentration of dense nanoparticles into a 3D space. The generated 3D hotspots enable the highly-sensitive detection of ultratrace analytes and simultaneous multiplex identification of different amino acids, which are well-known molecules with low Raman cross-sections. This platform demonstrates an excellent mechanical stability and is suitable for the excellent examination of ultratrace analytes, with detection limits as low as 0.01 fmol of dye molecules and 5 pmol of amino acids with extremely low Raman cross-sections.
authors: Department of Oncology, The First Affiliated Hospital of Anhui Medical University, Hefei 230022, P.R. China. sungp@ahmu.edu.cn.
authors: Hongyan
authors: H
authors: Wang
authors: Jinmei
authors: J
authors: Fang
authors: Jifei
authors: J
authors: Xu
authors: Fan
authors: F
authors: Wang
authors: Bai
authors: B
authors: Sun
authors: Shengnan
authors: S
authors: He
authors: Guoping
authors: G
authors: Sun
authors: Honglin
authors: H
authors: Liu
mesh_terms: D000596:Amino Acids / Q000032:analysis*; D004867:Equipment Design; D053768:Metal Nanoparticles / Q000737:chemistry*; D012834:Silver / Q000737:chemistry*; D013059:Spectrum Analysis, Raman / Q000295:instrumentation*
chemical_list: D000596:Amino Acids; D012834:Silver