Measuring the poise of thiol/disulfide couples in vivo.

ABSTRACT: The reduction potentials (E(h)) for the redox couples GSH/GSSG and cysteine/cystine (Cys/CySS) in plasma are useful indicators of systemic oxidative stress and other medically relevant physiological states. This article describes a sensitive method for determining plasma levels of GSH, GSSG, Cys, and CySS used to calculate the in vivo E(h) values. The method uses iodoacetate to alkylate free thiols, derivatization with dansyl chloride to fluorescently tag amino groups, and HPLC and fluorescence to separate, detect, and quantify the molecules. Benefits of the method, such as sensitivity and dynamic range, are described, as are caveats, such as the importance of preventing red blood cell hemolysis and limitations in quantification of GSSG. General principles of redox chemistry and previous s

SUBMITTER: Jones DP 

PROVIDER: S-EPMC2774737 | biostudies-literature | 2009 Nov

REPOSITORIES: biostudies-literature