title: Efficient fluorescence turn-on probe for zirconium via a target-triggered DNA molecular beacon strategy.
abstract: It is well-known that Zr(4+) could selectively bind with two phosphate-functionalized molecules through a coordinate covalent interaction to form a sandwich-structured complex (-PO(3)(2-)-Zr(4+)-PO(3)(2-)-). In this paper, we for the first time converted such interaction into fluorescence sensing systems for Zr(4+) via a target-triggered DNA molecular beacon strategy. In the new designed sensing system, two phosphorylated and pyrene-labeled oligonucleotides were chosen as both recognition and reporter units, which will be linked by target Zr(4+) to form a hairpin structure and bring the two labeled pyrene molecules into close proximity, resulting in a "turn-on" excimer fluorescence signal. Moreover, γ-cyclodextrin was introduced to afford an amplified fluorescence signal and, therefore, provided an improved sensitivity for the target Zr(4+). This allows detection of Zr(4+) with high sensitivity (limit of detection, LOD = 200 nM) and excellent selectivity. The proposed sensing system has also been used for detection of Zr(4+) in river water samples with satisfactory result.
authors.affiliation: State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, P. R. China.
authors.forename: Hong-Min
authors.initials: HM
authors.lastname: Meng
authors.forename: Ting
authors.initials: T
authors.lastname: Fu
authors.forename: Xiao-Bing
authors.initials: XB
authors.lastname: Zhang
authors.forename: Nan-Nan
authors.initials: NN
authors.lastname: Wang
authors.forename: Weihong
authors.initials: W
authors.lastname: Tan
authors.forename: Guo-Li
authors.initials: GL
authors.lastname: Shen
authors.forename: Ru-Qin
authors.initials: RQ
authors.lastname: Yu
mesh_terms: D004247:DNA / Q000737:chemistry*; D005456:Fluorescent Dyes / Q000737:chemistry*; D005618:Fresh Water / Q000032:analysis; D010710:Phosphates / Q000737:chemistry; D011721:Pyrenes / Q000737:chemistry; D013050:Spectrometry, Fluorescence; D015040:Zirconium / Q000032:analysis*; D047408:gamma-Cyclodextrins / Q000737:chemistry
chemical_list: D005456:Fluorescent Dyes; D010710:Phosphates; D011721:Pyrenes; D047408:gamma-Cyclodextrins; D004247:DNA; C030984:pyrene; D015040:Zirconium