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Fluorescent coumarin thiols measure biological redox couples.

ABSTRACT: 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 ? 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.

SUBMITTER: Reddie KG

PROVIDER: S-EPMC3291176 | biostudies-literature | 2012 Feb

REPOSITORIES: biostudies-literature

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Fluorescent coumarin thiols measure biological redox couples.

Reddie Khalilah G KG Humphries William H WH Bain Charlo P CP Payne Christine K CK Kemp Melissa L ML Murthy Niren N

Organic letters 20120120 3

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 it ...[more]

PMID: 22264005

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