Determination of Thiols and Disulfides in Whole Blood and Its Fractions by Anodic Stripping Voltammetry and Anodic Stripping Voltammetric Titration

Abstract

SH- and SS-groups content and their ratio is one of the most important factors of organism antioxidant system. Change in ratio of thiols to disulfides can serve as an indicator of oxidative stress. Anodic stripping voltammetry and anodic stripping voltammetric titration (direct and reverse variants) methods are proposed for determination of thiols and disulfides concentration. Disulfides are preliminary reduced with sodium sulfite. Ag++RSHAgSR+H+ reaction is used to provide the information. Unreacted silver ions concentration is determined by anodic stripping voltammetry method using platinum working electrode. Calibration free method is suggested. The possibilities of express analysis of blood and its fractions are described. Reliability of results and accuracy are confirmed by model solutions analysis and recovery study of whole blood and its fractions. Results of whole blood, erythrocyte mass, plasma and serum taken from different groups of patients' investigations are given, that demonstrate perspectives of the application methods in clinical practice.