An "off-on" fluorescent and colorimetric probe bearing fluorescein moiety for Mg(2+) and Ca(2+) via a controlled supramolecular approach

Mater Sci Eng C Mater Biol Appl. 2014 Jun 1:39:73-7. doi: 10.1016/j.msec.2014.02.030. Epub 2014 Feb 24.

Abstract

In the present work, a new kind of fluorescein-based chemosensor L was designed and synthesized to selectively recognize Ca(2+) or Mg(2+) over other competing ions. The chemosensor showed "off-on" fluorescent and color changes upon the addition of Ca(2+) and Mg(2+). The dynamic binding events with the formation of 1:1(L/M) and 1:2(L/M) complexes were examined. The cation-driven conformation changes of L were understood and proposed rationally by the UV-vis, FL, and (1)HNMR titrations. By this allosteric effect, Ca(2+) and Mg(2+) could be selectively recognized with the 1:2 stoichiometry by fluorescent changes, which were different from other known reports on chemosensors that the host-cation complexion was exploited for controlling chromophore interaction as the model of signaling.

Keywords: Calcium; Chemosensor; Fluorescence; Magnesium; Naked-eye detection; Supramolecular.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Calcium / analysis*
  • Cations / chemistry
  • Colorimetry / methods*
  • Fluorescein*
  • Fluorescent Dyes*
  • Ions / chemistry
  • Limit of Detection
  • Magnesium / analysis*
  • Magnetic Resonance Spectroscopy
  • Molecular Conformation
  • Spectrometry, Fluorescence

Substances

  • Cations
  • Fluorescent Dyes
  • Ions
  • Magnesium
  • Calcium
  • Fluorescein