Related Experiment Video
Updated: May 10, 2026

Rapid Quantification of Oxidized and Reduced Forms of Glutathione Using Ortho -phthalaldehyde in Cultured Mammalian Cells In Vitro
Published on: June 28, 2024
Glutathione and γ-glutamylcysteine in hydrogen peroxide detoxification
Ruben Quintana-Cabrera1, Juan P Bolaños
1Institute of Functional Biology and Genomics (IBFG), Department of Biochemistry and Molecular Biology, University of Salamanca-CSIC, Salamanca, Spain.
Abstract:
Hydrogen peroxide (H2O2) is an important regulator of cell redox status and signaling pathways. However, if produced in excess, it can trigger oxidative damage, which can be counteracted by the antioxidant systems. Amongst these, the glutathione (GSH) precursor, γ-glutamylcysteine (γGC), has recently been shown to detoxify H2O2 in a glutathione peroxidase-1 (GPx1)-dependent fashion. To analyze how both γGC and GSH reduce H2O2, we have taken advantage of a colorimetric assay that allows simple and reliable quantification of H2O2 in the micromolar range. Whereas most assays rely on coupled enzymatic reactions, this method determines the formation of a ferric thiocyanate derivative after direct Fe(2+) oxidation by H2O2. Here, we detail the procedure and considerations to determine H2O2 reduction by both γGC and GSH, either from cell samples or in vitro reactions with purified enzymes from GSH metabolism.
More Related Videos
Related Concept Videos
Phase II Reactions: Glutathione Conjugation and Mercapturic Acid Formation
Several distinctive characteristics distinguish glutathione conjugation from other phase II...
Peroxisomes
Peroxisomes and Mitochondria
The peroxisome is a single membrane-bound cellular organelle that can perform several different functions, including lipid metabolism and chemical detoxification. The enzymes within peroxisomes...
Peroxisomes
Phase II Reactions: Glucuronidation
Drug Metabolism: Phase II Reactions

