title: Rhodamine-based ratiometric fluorescence sensing for the detection of mercury(II) in aqueous solution.
abstract: Novel ratiometric fluorescent silica nanoparticles with high selectivity towards Hg(2+) were synthesized for the detection of Hg(2+). Hg(2+) promoted the ring opening of spirolactam in the rhodamine moiety grafted onto the silica nanoparticles, resulting in a change in the fluorescence intensity. The fluorescence intensity was proportional to the Hg(2+) concentration, and the detection limit (S/N=3) for Hg(2+) was found to be 2.59 x 10(-9) mol L(-1) with a linear range from 0.4 to 8 x 10(-7) mol L(-1). In addition, the morphology of the silica nanoparticles, the effects of pH and co-existing substances, and the reversibility were investigated. The proposed approach was successfully applied to the determination of Hg(2+) in water samples.
authors.affiliation: Key Laboratory of Analysis and Detection Technology for Food Safety, Ministry of Education, Department of Chemistry, Fuzhou University, Fuzhou 350002, China.
authors.forename: Haizhu
authors.initials: H
authors.lastname: Liu
authors.forename: Ping
authors.initials: P
authors.lastname: Yu
authors.forename: Dan
authors.initials: D
authors.lastname: Du
authors.forename: Chunyan
authors.initials: C
authors.lastname: He
authors.forename: Bin
authors.initials: B
authors.lastname: Qiu
authors.forename: Xi
authors.initials: X
authors.lastname: Chen
authors.forename: Guonan
authors.initials: G
authors.lastname: Chen
mesh_terms: D002623:Chemistry Techniques, Analytical / Q000295:instrumentation*; D005456:Fluorescent Dyes / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008628:Mercury / Q000032:analysis*; D053758:Nanoparticles / Q000737:chemistry; D015203:Reproducibility of Results; D012235:Rhodamines / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry; D012996:Solutions; D013050:Spectrometry, Fluorescence; D013499:Surface Properties; D014867:Water / Q000737:chemistry*
chemical_list: D005456:Fluorescent Dyes; D012235:Rhodamines; D012996:Solutions; C026188:rhodamine 6G; D014867:Water; D012822:Silicon Dioxide; D008628:Mercury