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Assessment of Cellular Oxidation using a Subcellular Compartment-Specific Redox-Sensitive Green Fluorescent Protein
Published on: June 18, 2020
Fluorescent coumarin thiols measure biological redox couples
Khalilah G Reddie1, William H Humphries, Charlo P Bain
1Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30032, USA.
None:
In this report we present a new chemical probe, 3-HTC, that can reversibly and ratiometrically measure the thiol-disulfide equilibrium of biological systems. 3-HTC is composed of a coumarin that has a thiolate directly conjugated to its extended aromatic π system while formation of a disulfide attenuates this conjugation. The fluorescence and absorption properties of 3-HTC are therefore very sensitive to the redox state of its thiol. 3-HTC reacts reversibly with thiols and disulfides enabling its use to measure dynamic GSH/GSSH ratios in vitro as well as to monitor the reversible redox status of whole cell lysates.
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