Description
Principle of the Assay::The OxiSelect™ Hydrogen Peroxide/Peroxidase Assay Kit is a sensitive quantitative colorimetric assay for hydrogen peroxide or peroxidase. In the presence of peroxidase, the probe reacts with H2O2 in a 1:1 stoichiometry to produce a bright pink colored product. This product can be easily read by a standard colorimetric microplate reader with a filter in the 540-570 nm range. Absorbance values are proportional to the H2O2 or peroxidase levels within the samples, depending on the assay employed. The H2O2 or peroxidase content in unknown samples is determined by comparison with its respective standard curve.
Background/Introduction: Oxidative stress is a physiological condition where there is an imbalance between concentrations of reactive oxygen species (ROS) and antioxidants. Research has shown that excessive ROS accumulation will lead to cellular injury, such as damage to DNA, proteins, and lipid membranes. Peroxides, such as hydrogen peroxide (H2O2), are some of the most well documented ROS produced under oxidative stress conditions. Hydrogen peroxide is an ROS that is a toxic product of normal aerobic metabolism and pathogenic ROS production involving oxidase and superoxide dismutase reactions. Hydrogen peroxide is poisonous to eukaryotic cells and in high doses can initiate oxidation of DNA, lipids, and proteins, which can lead to mutagenesis and cell death. The cellular damage caused by peroxides have been implicated in the development of many pathological conditions, such as ageing, asthma, arthritis, diabetes, cardiovascular disease, atherosclerosis, Down's Syndrome, and neurodegenerative diseases. OxiSelect™ Hydrogen Peroxide/Peroxidase Assay Kit is a simple HTS-compatible assay for measuring hydrogen peroxide concentrations or peroxidase activities in biological samples without any need for pretreatment. The colorimetric probe reacts with H2O2 and horseradish peroxidase enzyme (HRP) to produce a pink colored product. The probe has less background and greater stability than the commonly used Xylenol Orange (FOX) colorimetric assay for H2O2. The probe can be also used as an ultrasensitive assay for peroxidase activity when H2O2 is in excess. The kit has a detection sensitivity limit of 500 nM (H2O2) or 0.2 mU/mL (oeroxidase). Each kit provides sufficient reagents to perform up to 500 assays, including standard curve and unknown samples