Oxidative stress, broadly defined as an imbalance between reactive oxygen species production and elimination by antioxidant defenses, can lead to oxidative damage to critical cellular structural and functional biomarkers when unchecked. Implicated in a variety of pathophysiological and age-related diseases, many research programs focus on understanding oxidative stress’ role in health and disease. Arbor Assays provides tools to measure the status and activity of key oxidative stress biomarkers. Our glutathione and hydrogen peroxide assays are the easiest, most sensitive assays available to help researchers better monitor oxidative stress mechanisms and responses.