A New Fluorescent Chemosensor for Copper Ions Based on Tripeptide Glycyl−Histidyl−Lysine (GHK)
Department of Chemistry, University of Miami, كورال غيبلز، فلوريدا, Florida, United States Organic Letters
(Impact Factor: 6.36).
11/2001; 3(21):3277-80. DOI: 10.1021/ol0101638
[structure: see text]. A new fluorescent chemosensor for Cu2+ ions was synthesized by modifying the tripeptide glycyl-histidyl-lysine (GHK) with 9-carbonylanthracene via the standard Fmoc solid-phase peptide synthesis method. While significant fluorescence quenching was observed from the molecule upon binding with Cu2+, addition of Fe2+, Co2+, Ni2+, and Zn2+ to the peptide solution caused a minimum fluorescence emission spectral change, indicating a high specificity of this chemosensor for Cu2+ ions. Effects of pH were also investigated.
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- "The two units are linked to each other in such a way that the binding of an imidazolate anion to the ionophore causes considerable changes in the fluorescence of the fluorophore. Such changes can be intensity, intensity ratio, anisotropy, time-domain lifetime or phase-modulation lifetime, etc (Zheng et al., 2001). The high sensitivity and abundance of fluorophores makes fluorescence technique among one of the most promising tools for chemo-and biosensor development. "
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