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

Authors

Xinqi Zhou, University of Nebraska - LincolnFollow
Lauren Lesiak, University of Nebraska - Lincoln
Rui Lai, University of Nebraska-LincolnFollow
Jon R. Beck, University of Nebraska - Lincoln
Jia Zhao, University of Nebraska - Lincoln
Christian Elowsky, University of Nebraska-LincolnFollow
Hui Li, University of Nebraska - LincolnFollow
Cliff I. Stains, University of Nebraska-LincolnFollow

Document Type

Article

Date of this Version

2017

Citation

Angew Chem Int Ed Engl. 2017 April 03; 56(15): 4197–4200.

Comments

Copyright (c) 2017 Wiley-VCH Verlag GmbH & Co.

doi:10.1002/anie.201612628

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 H₂O₂ sensors. Both these fluorophores display far-red to near-infrared excitation and emission prior to reaction. Upon oxidation by H₂O₂ 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.