Fluorescent peptide sensor for the selective detection of Cu2+.
A new fluorescent peptidyl chemosensor for Cu(2+) ions with fluorescence resonance energy transfer (FRET) capabilities has been synthesized via Fmoc solid-phase peptide synthesis. The metal chelating unit, which is flanked by the fluorophores tryptophan (donor) and dansyl chloride (acceptor), consists of the amino acids glycine and aspartic acid (Gly-Gly-Asp-Gly-Gly-Asp-Gly-Gly-Asp-Gly-Gly-Asp-Gly-Gly). Coordination of the Cu(2+) ions to the metal chelating unit results in fluorescent quenching of both the donor and acceptor fluorophores. Although it was determined that Cu(2+) binding causes no change in FRET efficiency, emission and Cu(2+)-induced quenching of the acceptor dye can be used to monitor the concentration of the copper ions, with a detection limit of 32microgL(-1). The sensor also demonstrated sensitivity, reversibility and selectivity towards Cu(2+) in a transition metal matrix at pH 7.0.
White
Brianna R
BR
Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, TX 78712, USA.
Holcombe
James A
JA