StressMarq's Superoxide dismutase (SOD) Assay

stressmarq superoxide dismutase SOD activity kit

• Scientific Background of Superoxide Dismutase (SOD)
• StressXpress® SOD Assay Overview
• Kit Specifications
• Resources

Scientific Background of SOD

Short-lived and highly reactive oxygen species (ROS) such as O2·- (superoxide), ·OH (hydroxyl radical), and H2O2 (hydrogen peroxide) are continuously
generated in vivo. In the resting state, the balance between antioxidants and
oxidants is sufficient to prevent the disruption of normal physiologic functions;
however, either increases in oxidants or decreases in antioxidants can disrupt this balance giving rise to elevated levels of reactive oxygen species (ROS) (1,2).

The cellular levels of ROS are controlled by antioxidant enzymes and small
molecule antioxidants. The major antioxidant enzymes, superoxide dismutases
, including copper-zinc superoxide dismutase (Cu/ZnSOD, SOD1),
manganese superoxide dismutase (MnSOD, SOD2) and extracellular superoxide dismutase (EC-SOD, SOD3), all play critical roles in scavenging O2·-.

Decreased SOD activity results in elevated level of superoxide which in turn leads to decreased NO but increased peroxynitrite concentrations. The major intracellular SOD is a 32-kD copper and zinc containing homodimer (Cu/Zn SOD). The mitochondrial SOD (MnSOD) is a manganese-containing 93-kD homotetramer that is synthesized in the cytoplasm and translocated to the inner matrix of mitochondria. EC-SOD is the primary extracellular SOD enzyme and is highly expressed in many organs. Increased SOD activity levels are seen in Downs
Syndrome (3) while decreased activity is seen in diabetes, Alzheimer’s disease,
rheumatoid arthritis, Parkinson’s disease, uremic anemia, atherosclerosis, some cancers, and thyroid dysfunction


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StressXpress® SOD Assay Overview

The Superoxide Dismutase (SOD) Colorimetric Activity Kit is designed to quantitatively measure SOD activity in a variety of samples. The assay measures all types of SOD activity, including Cu/Zn, Mn, and FeSOD types.

A bovine erythrocyte SOD standard is provided to generate a standard curve for the assay and all samples should be read off of the standard curve. Samples are diluted in our specially colored Sample Diluent and added to the wells. The Substrate is added followed by Xanthine Oxidase Reagent and incubated at room temperature for 20 minutes. The Xanthine Oxidase generates superoxide in the presence of oxygen, which converts a colorless substrate in the Detection Reagent into a yellow colored product. The colored product is read at 450 nm. Increasing levels of SOD in the samples causes a decrease in superoxide concentration and a reduction in yellow product. The activity of the SOD in the sample is calculated after making a suitable correction for any dilution, using software available with most plate readers. The results are expressed in terms of units of SOD activity per mL.


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Kit Specification


Product Name SOD StressXpress® Colorimetric Activity Kit
Cat # SKT-214
Description Quantitatively measure SOD activity in a variety of samples.
Research Area Oxidative Stress
Alternative Names Cu/ZnSOD, SOD1, MnSOD, SOD2, EC-SOD, SOD3
Species Reactivity Species Independent
Sample Types Serum, Urine and Buffer
Sensitivity 0.044 U/mL
Other Relevant Info Samples/Kit: 89 in duplicate

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