title: Design, properties and application of a facile fluorescence switch for Cu(II).
abstract: A facile fluorescence switch based on Schiff base 2,2'-[1,3-phenylenbis- (methylidynenitrilo)]bis[benzenethiol] (PMBB) has been developed and used to sensing metal ions. UV-vis absorption and fluorescence emission spectra show that the PMBB receptor has high selectivity and sensitivity for Cu(II) ions. Based on the photoinduced electron transfer (PET) and chelation enhanced fluorescence (CHEF) mechanisms, the receptor exhibits an fluorescence "turn-on" switch signal for Cu(II). The 1:1 binding mode of PMBB and Cu (II) ions can be obtained by the Job-plot and ESI-Mass spectra data. Noticeably, the color changes (from colorless to yellow) of PMBB solutions for Cu(II) sensing can be observed by naked eyes in the sunlight. The detection limit of the receptor for Cu(II) may reach 10(-7)mol/L with a good linear relation in the lower concentrations of Cu(II). To develop the practical application, the Cu(II) ions in swimming pool water samples were detected. Results show that PMBB receptor as a fluorescent probe can use to detect the trace level of Cu(II) in the environmental samples. This work contributes to providing a facile strategy for designing efficient probes and developing their practical application value.
authors.affiliation: School of Basic Medical Sciences, Shanxi Medical University, Taiyuan 030001, PR China.
authors.forename: Haipeng
authors.initials: H
authors.lastname: Diao
authors.affiliation: School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, PR China; Shanxi Station for Plant Protection and Quarantine, Taiyuan 030001, PR China.
authors.forename: Weiping
authors.initials: W
authors.lastname: Niu
authors.affiliation: School of Basic Medical Sciences, Shanxi Medical University, Taiyuan 030001, PR China.
authors.forename: Wen
authors.initials: W
authors.lastname: Liu
authors.affiliation: School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, PR China. Electronic address: lhfeng@sxu.edu.cn.
authors.forename: Liheng
authors.initials: L
authors.lastname: Feng
authors.affiliation: School of Basic Medical Sciences, Shanxi Medical University, Taiyuan 030001, PR China. Electronic address: xiejunty@yahoo.com.
authors.forename: Jun
authors.initials: J
authors.lastname: Xie
keywords: Fluorescence probe; Metal ions; Off-on; Schiff base; Water samples