title: New probe design strategy by cooperation of metal/DNA-ligation and supermolecule inclusion interaction: application to detection of mercury ions(II).
abstract: In this paper, the development is described of an efficient pyrene excimer signaling-based fluorescent sensor for the measurement of mercury ions in aqueous solutions based on thymine-Hg(2+)-thymine (T-Hg(2+)-T) coordination chemistry and the inclusion interaction of γ-cyclodextrin. Introduction of cyclodextrin can provide cooperation for the molecular level space proximity of the two labeled pyrene molecules, moreover the hydrophobic cavity of γ-cyclodextrin can also offer protection for the pyrene dimer's emission from the quenching effect of Hg(2+) and enhance the fluorescence intensity of the pyrene excimer. To demonstrate the feasibility of the design, a bis-pyrene-labeled thymine-rich DNA strand was used as the detection probe. In the presence of Hg(2+), stem-close-shaped DNA strands can be formed with the cooperation of γ-cyclodextrin and ideally predominantly emit the excimer fluorescence. The selectivity of the sensor for Hg(2+) against other biologically and environmentally related metal ions is outstanding due to the high specificity of T-Hg(2+)-T formation. In addition, the pyrene excimer has a long fluorescence lifetime, which can tolerate intense background fluorescence interference from complex biological components, making it potentially applicable in the analysis of complex biological samples.
authors.affiliation: State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China.
authors.forename: Xiaoxia
authors.initials: X
authors.lastname: Gao
authors.forename: Ting
authors.initials: T
authors.lastname: Deng
authors.forename: Jishan
authors.initials: J
authors.lastname: Li
authors.forename: Ronghua
authors.initials: R
authors.lastname: Yang
authors.forename: Guoli
authors.initials: G
authors.lastname: Shen
authors.forename: Ruqin
authors.initials: R
authors.lastname: Yu
mesh_terms: D001483:Base Sequence; D002413:Cations, Divalent / Q000032:analysis; D004247:DNA / Q000737:chemistry; D060766:Drinking Water / Q000032:analysis*; D005456:Fluorescent Dyes / Q000737:chemistry*; D057230:Limit of Detection; D008628:Mercury / Q000032:analysis*; D011721:Pyrenes / Q000737:chemistry*; D045483:Rivers / Q000737:chemistry; D013050:Spectrometry, Fluorescence / Q000379:methods; D013941:Thymine / Q000737:chemistry*; D047408:gamma-Cyclodextrins / Q000737:chemistry*
chemical_list: D002413:Cations, Divalent; D060766:Drinking Water; D005456:Fluorescent Dyes; D011721:Pyrenes; D047408:gamma-Cyclodextrins; D004247:DNA; C030984:pyrene; D008628:Mercury; C023792:gamma-cyclodextrin; D013941:Thymine