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941.
Azadbakht R Parviz M Tamari E Keypour H Golbedaghi R 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,82(1):200-204
A new macrocyclic chemosensor containing two naphthalene fluorophores has been synthesized. The fluorescent properties of this receptor has been studied in the presence of various metal ions such as Na+, Ag+, Cr3+, Mn2+, Fe3+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+ and Pb2+. When increasing concentrations of Zn2+ ions were introduced, the emission of L was drastically increased (EFE = 4.34). This special change was not observed when other metal ions were used; such highly selective fluorescent response indicates that this receptor can easily discriminate Zn2+ ions from other similar species. Model calculations at DFT level further suggest the possible interaction mode, and relatively steric position between the host and guest also influence the optical response. 相似文献
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Liu C Pan J Li S Zhao Y Wu LY Berkman CE Whorton AR Xian M 《Angewandte Chemie (International ed. in English)》2011,50(44):10327-10329
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An artificial site‐selective DNA cutter to hydrolyze single‐stranded DNA at a desired site was prepared from CeIV/ethylenediamintetraacetic acid (EDTA) and two ethylenediamine‐N,N,N′,N′‐tetrakis(methylenephosphonic acid)–oligonucleotide conjugates. By using this cutter, the sense strand of a blue fluorescent protein (BFP) gene was selectively cut at a predetermined site in the chromophore‐coding region. The upstream fragment obtained by the site‐selective scission was ligated with the downstream fragment of the closely related green fluorescent protein (GFP) gene so that the 5′‐ and 3′‐end portions of the chromophore came from the BFP fragment and the GFP fragment, respectively. The recombinant gene was successfully expressed in E. coli and the chimeric chromophore emitted green fluorescence as expected. 相似文献
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A series of Zn2+‐selective two‐photon fluorescent probes (AZnM1−AZnN) that had a wide range of dissociation constants (KdTP=8 nm‐ 12 μM ) were synthesized. These probes showed appreciable water solubility (>3 μM ), cell permeability, high photostability, pH insensitivity at pH>7, significant two‐photon action cross‐sections (86–110 GM) upon complexation with Zn2+, and can detect the Zn2+ ions in HeLa cells and in living tissue slices of rat hippocampal at a depth of >80 μm without mistargeting and photobleaching problems. These probes can potentially find application in the detection of various amounts of Zn2+ ions in live cells and intact tissues. 相似文献
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Two‐photon microscopy (TPM) has become an indispensible tool in biology and medicine owing to the capability of imaging the intact tissue for a long period of time. To make it a versatile tool in biology, a variety of two‐photon probes for specific applications are needed. In this context, many research groups are developing two‐photon probes for various applications. In this Focus Review, we summarize recent results on model studies and selected examples of two‐photon probes that can detect intracellular free metal ions in live cells and tissues to provide a guideline for the design of useful two‐photon probes for various in vivo imaging applications. 相似文献
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