title: A medium-controlled fluorescence dual-responsive probe for Cu2+ and Hg2+ in aqueous solutions.
abstract: In this study, we report a histidine-based fluorescence probe for Cu(2+) and Hg(2+), in which the amino group and imino group were modified by two common protective groups, 9-fluorenylmethoxycarbonyl and trityl group, respectively. In a water/methanol mixed solution, the probe displayed a selective fluorescence "turn-off" response to Cu(2+) when the ratio of CH(3)OH/H(2)O was higher than 1:1. Specifically, when the solvent is changed to 1:1 methanol/water, the 304 nm fluorescence peak is enhanced, while the 317 nm peak is weakened, upon addition of either Cu(2+) or Hg(2+) ions. The mechanism for such distinct responses of the probe to Cu(2+) and Hg(2+) was further clarified by using NMR and molecular simulation. The experiment results indicated that the polarity of solvent could influence the coordination mode of 1 with Cu(2+) and Hg(2+), and control the fluorescence response as a "turn-off" or ratiometric probe.
authors.affiliation: School of Chemistry and Environment, South China Normal University, Guangzhou, China. mlj898021@yahoo.com.cn
authors.forename: Li-Jun
authors.initials: LJ
authors.lastname: Ma
authors.forename: Liping
authors.initials: L
authors.lastname: Chen
authors.forename: Guirong
authors.initials: G
authors.lastname: Chen
authors.forename: Hong-Wei
authors.initials: HW
authors.lastname: Li
authors.forename: Liting
authors.initials: L
authors.lastname: Yang
authors.forename: Yuqing
authors.initials: Y
authors.lastname: Wu
authors.forename: Dan
authors.initials: D
authors.lastname: Wang
authors.forename: Jiewan
authors.initials: J
authors.lastname: Xie
mesh_terms: D056831:Coordination Complexes / Q000737:chemistry*; D003300:Copper / Q000032:analysis*; D005453:Fluorescence; D005456:Fluorescent Dyes / Q000737:chemistry*; D006639:Histidine / Q000031:analogs & derivatives* / Q000737:chemistry*; D008628:Mercury / Q000032:analysis*; D000432:Methanol; D056004:Molecular Dynamics Simulation; D015335:Molecular Probes; D015394:Molecular Structure; D012996:Solutions; D012997:Solvents; D013050:Spectrometry, Fluorescence; D014867:Water
chemical_list: D056831:Coordination Complexes; D005456:Fluorescent Dyes; D015335:Molecular Probes; D012996:Solutions; D012997:Solvents; D014867:Water; D006639:Histidine; D003300:Copper; D008628:Mercury; D000432:Methanol