title: Ultrasensitive determination of silver ion based on synchronous fluorescence spectroscopy with nanoparticles.
abstract: Based on the characteristics of synchronous fluorescence spectroscopy (SFS), a new method with high sensitivity and selectivity was developed for rapid determination of silver ion with functional cadmium sulphide (CdS) nanoparticles as a fluorescence probe. When Delta lambda (lambda(em) - lambda(ex)) = 215 nm, maximum synchronous fluorescence is produced at 304 nm. Under optimal conditions, functional cadmium sulphide displayed a calibration response for silver ion over a wide concentration range from 0.8x10(-10) to 1.5x10(-8) mol L(-1). The limit of detection was 0.4x10(-10) mol L(-1) and the relative standard deviation of seven replicate measurements for the lowest concentration (0.8x10(-10) mol L(-1)) was 2.8%. Compared with several fluorescence methods, the proposed method had a wider linear range and improved the sensitivity. Furthermore, the concentration dependence of the synchronous fluorescence intensity is effectively described by a Langmuir-type binding isotherm.
authors.affiliation: Anhui Key Laboratory of Chemo-Biosensing, College of Chemistry and Materials Science, Anhui Normal University, Wuhu 241000, PR China. wanglun@mail.ahnu.edu.cn
authors.forename: Lun
authors.initials: L
authors.lastname: Wang
authors.forename: A-Ni
authors.initials: AN
authors.lastname: Liang
authors.forename: Hong-Qi
authors.initials: HQ
authors.lastname: Chen
authors.forename: Yan
authors.initials: Y
authors.lastname: Liu
authors.forename: Bin-bin
authors.initials: BB
authors.lastname: Qian
authors.forename: Jie
authors.initials: J
authors.lastname: Fu
mesh_terms: D019187:Cadmium Compounds / Q000737:chemistry*; D005456:Fluorescent Dyes / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007477:Ions / Q000032:analysis; D046529:Microscopy, Electron, Transmission / Q000379:methods; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D015203:Reproducibility of Results; D012834:Silver / Q000032:analysis*; D013050:Spectrometry, Fluorescence / Q000379:methods; D013440:Sulfides / Q000737:chemistry*; D013864:Thioglycolates / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D019187:Cadmium Compounds; D005456:Fluorescent Dyes; D007477:Ions; D013440:Sulfides; D013864:Thioglycolates; C034939:cadmium sulfide; D014867:Water; D012834:Silver; C017487:2-mercaptoacetate