Chemoselective Alteration of Fluorophore Scaffolds as a Strategy for the Development of Ratiometric Chemodosimeters

Angew Chem Int Ed Engl. 2017 Apr 3;56(15):4197-4200. doi: 10.1002/anie.201612628. Epub 2017 Mar 20.

Abstract

Ratiometric sensors generally couple binding events or chemical reactions at a distal site to changes in the fluorescence of a core fluorophore scaffold. However, such approaches are often hindered by spectral overlap of the product and reactant species. We provide a strategy to design ratiometric sensors that display dramatic spectral shifts by leveraging the chemoselective reactivity of novel functional groups inserted within fluorophore scaffolds. As a proof-of-principle, fluorophores containing a borinate (RF620 ) or silanediol (SiOH2R) functionality at the bridging position of the xanthene ring system are developed as endogenous H2 O2 sensors. Both these fluorophores display far-red to near-infrared excitation and emission prior to reaction. Upon oxidation by H2 O2 both sensors are chemically converted to tetramethylrhodamine, producing significant (≥66 nm) blue-shifts in excitation and emission maxima. This work provides a new concept for the development of ratiometric probes.

Keywords: bioorthogonal reaction; fluorescent probes; reactive oxygen species; sensors; signal transduction.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Borinic Acids / chemistry
  • Fluorescent Dyes / chemical synthesis*
  • Fluorescent Dyes / chemistry
  • HeLa Cells
  • Humans
  • Microscopy, Confocal
  • Microscopy, Fluorescence
  • Molecular Structure
  • Rhodamines / chemical synthesis*
  • Rhodamines / chemistry
  • Silanes / chemistry
  • Xanthenes / chemistry

Substances

  • Borinic Acids
  • Fluorescent Dyes
  • Rhodamines
  • Silanes
  • Xanthenes
  • silanediol
  • tetramethylrhodamine