Thermo Scientific™ Pierce™ Peroxide Assay Reagent A

These aqueous and lipid-compatible peroxide assay kits detect peroxides based on oxidation of ferrous to ferric ion in the presence of xylenol orange. One assay kit has an aqueous-compatible formulation that includes sorbitol, which provides sensitivity enhancement. The other assay kit has a formulation that may be used with lipid-containing samples without first extracting the lipids; however, because this kit does not contain sorbitol, the assay is less sensitive. Most proteins do not interfere with these assays, although some metal chelators may require use of a blank (i.e., control) to mitigate these effects.

In these assays, hydroperoxides convert the Fe2+ to Fe3+ at acidic pH. With the aqueous-compatible formulation, peroxide first reacts with sorbitol, converting it to a peroxyl radical, which in turn initiates Fe2+ oxidation to Fe3+. In the lipid compatible formulation, the peroxide converts the Fe2+ to Fe3+ directly. In a sulfuric acid solution, the Fe3+ complexes with the xylenol orange (XO) dye to yield a purple product having an absorbance maximum at 560nm. Peroxide levels in test samples can be determined by calculation from the know extinction coefficient of the XO-Fe complex or by reference to a standard curve prepared with hydrogen peroxide solution.

Highlights:

• Peroxides – detects and measures hydrogen peroxide (H2O2) levels in biological and other liquids samples
• Convenient – no proprietary reagents involved but the ready-to-use kits remove the variability, difficulty and added expense of formulating the reagents yourself
• Versatile – quantitation by calculation from the extinction coefficient or by reference to a standard curve enables the method to be easily adapted to a variety of sample types and testing purposes
• Two formulations – choose the aqueous-compatible kit for maximum sensitivity with non-lipid samples; choose the lipid-compatible kit for best results with lipid-containing samples