Publications

Detection of Zn.sup.2+, Cd.sup.2+, Hg.sup.2+, and Pb.sup.2+ ions through label-free poly-L-glutamic acid

Faculty Author(s): Elioff, Michael S.
Student Author(s): -
Department: CHEM
Publication: Talanta
Year: 2018
Abstract: To access, purchase, authenticate, or subscribe to the full-text of this article, please visit this link: http://dx.doi.org/10.1016/j.talanta.2018.06.012 Byline: Jingqiu Hu [jhu@wcupa.edu] (a,*), Michael S. Elioff (b) Keywords Chemical sensors; Poly-L-glutamic acids; Charge shift state; Fluorescent emission; Heavy metal ions Highlights * Without group IIB or Pb.sup.2+ ions, the sensor in polypeptide displays no emission. * The sensor exhibits strong emission in the presence of Zn.sup.2+, Cd.sup.2+, Hg.sup.2+, and Pb.sup.2+ions. * The sensor emits green light for Zn.sup.2+, yellow for Cd.sup.2+, and orange for Hg.sup.2+ and Pb.sup.2+ ions. * EDTA can completely quenched the sensor emission for Zn.sup.2+, Cd.sup.2+, and Pb.sup.2+ ions. Abstract Detection of heavy metal ions in water is important for environmental sustainability and food safety. Current fluorescent sensors interact with metal ions directly through chelation or chemical reactions. Those sensors are expensive to produce and often can detect only one ion at a time. Here we report a fluorescent turn-on sensor that can detect three group IIB metal ions and Pb.sup.2+ ions through label-free polypeptides in water. In our sensor-polypeptide mixture, Zn.sup.2+, Cd.sup.2+, Hg.sup.2+, and Pb.sup.2+ ions induce helix formation and inter-chain aggregation in poly-L-[alpha]-glutamic acid (PGA). The acridinium-based sensor molecules incorporate into the polypeptides and emit strongly with characteristic color for each group IIB ion under UV lamp. By adjusting the size of polypeptides or the length of the side chain carboxyl groups, we can selectively turn off or turn on the sensor emission for Hg.sup.2+ ions. Author Affiliation: (a) Department of Chemistry, West Chester University of Pennsylvania, West Chester, PA 19383, United States (b) Department of Chemistry, Millersville University of Pennsylvania, Millersville, PA 17551, United States * Corresponding author. Article History: Received 12 March 2018; Revised 1 June 2018; Accepted 2 June 2018
Link: Detection of Zn.sup.2+, Cd.sup.2+, Hg.sup.2+, and Pb.sup.2+ ions through label-free poly-L-glutamic acid