For analysis of xanthine oxidase in plasma, serum, and tissue homogenates.

• Measure XO activity in plasma, serum, and tissue homogenates
• Assay 42 samples in duplicate
• Measure XO activity down to 10 µU/mL
• Plate-based fluorometric measurement (ex 520 – 550 nm, em 585 – 595 nm)

XO catalyzes the hydroxylation of hypoxanthine to xanthine and then further catalyzes the oxidation of xanthine to uric acid. When oxidizing NADH, XO generates superoxide, a powerful ROS. XO is found predominantly in the liver and intestine. However, levels of circulating XO can increase dramatically with disease. Cayman’s XO Assay provides a simple and accurate method for quantifying xanthine oxidase activity. The assay is based on a multistep enzymatic reaction whose end product resorufin, a highly fluorescent compound, can be easily analyzed using an excitation wavelength between 520 – 550 nm and an emission wavelength between 585 – 595 nm.