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Updated: Aug 16, 2026

Characterization of G Protein-coupled Receptors by a Fluorescence-based Calcium Mobilization Assay
Published on: July 28, 2014
Coumarin-strapped calix[4]pyrrole: a fluorogenic anion receptor modulated by cation and anion binding
Hidekazu Miyaji1, Hae-Kyung Kim, Eun-Kyung Sim
1Department of Chemistry and Institute of Basic Science, Kangwon National University, Chun-Chon 200-701 Korea.
Abstract:
A new strapped calix[4]pyrrole containing a fluorophore as part of the strap has been synthesized and characterized. Association constants with various anions have been determined using both fluorescence titration and isothermal titrations calorimetry (ITC). The two sets of association constants were found to be in good agreement with one another. The fluorescence emission properties of this new receptor could be controlled by addition of Na+ (or H2O) and anions. However, the fluorescence quenching by anions is only observed in the presence of Na+ (or H2O). All the experimental evidence is consistent with the notion that independent PET processes are modulated by separate cation and anion recognition events. As such, this system operates as an elementary logic gate wherein anion and cation concentrations serve as the input and fluorescence intensity changes provide the output.
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