Background: 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. The 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. In the presence of H2O2 and horseradish peroxidase (HRP), non-fluorescent ADHP (10-Acetyl-3, 7-dihydroxyphenoxazine) is oxidized to the highly fluorescent Resorufin. The probe has less background and greater stability. The ADHP-based H2O2 detection is at least one order of magnitude more sensitive 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 50 nM (H2O2) or 0.1 mU/mL (Peroxidase). Each kit provides sufficient reagents to perform up to 500 assays, including standard curve and unknown samples.

Principle of the Assay: The OxiSelect™ Hydrogen Peroxide/Peroxidase Assay Kit is a sensitive quantitative fluorometric assay for hydrogen peroxide or peroxidase. In the presence of HRP, ADHP reacts with H2O2 in a 1:1 stoichiometry to produce highly fluorescent Resorufin. The Resorufin product can be easily read by a fluorescence microplate reader with an excitation of 530-560 nm and an emission of 590 nm. Fluorescence values are proportional to the H2O2 or peroxidase levels within the samples. The H2O2 or peroxidase content in unknown samples is determined by comparison with its respective standard curve.

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Small volumes of OxiSelect Hydrogen Peroxide / Peroxidase assay kit vial(s) may occasionally become entrapped in the seal of the product vial during shipment and storage. If necessary, briefly centrifuge the vial on a tabletop centrifuge to dislodge any liquid in the container`s cap. Certain products may require to ship with dry ice and additional dry ice fee may apply.

MBS168736 is an assay kit targeting OxiSelect Hydrogen Peroxide / Peroxidase. Also known as OxiSelect Hydrogen Peroxide / Peroxidase Assay Kit (Fluorometric).