Protein Carbonyl Assays

The most common product of protein oxidation in biological samples are the carbonyl derivatives of proline, arginine, lysine and threonine residues. Such derivatives are chemically stable and found universally across all proteins.

Many oxidative stress markers degrade over time, but Protein carbonyl content can still be measured reliably even in samples frozen for up to 1-2 years.

Our OxiSelect™ Protein Carbonyl Assays allow fast, reliable measurement of protein damage. A variety of formats is available including Western blot, fluorometric, spectrophotometric, and the most popular ELISA kit.
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TECH CORNER: Testing Samples for Oxidative Stress


Q: I want to test my samples for oxidative stress, but there are so many different oxidative stress assay kits. How do I know which kits to use? 

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For more Frequently Asked Questions on Oxidative Stress click here.

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Advanced Glycation End Product (AGE) Assays

AGE modification of proteins can contributeto the pathophysiology of aging and long-term complications of diabetes, atherosclerosis and renal failure.

Our range of AGE assays include an AGE ELISA Kit to broadly detect the formation of advanced glycation end products, as well as ELISA kits to detect specific AGE species: 

Nitrotyrosine Assays

The presence of nitric oxide, via the intermediate reactive molecule peroxynitrite, most often results in nitration of tyrosine residues (i.e. formation of 3-Nitrotyrosine) in proteins. The 3-Nitrotyrosine marker is extremely stable and easily measured in cell lysates, plasma, or serum.


Our Nitrotyrosine Assay Kits are available in two formats: Western blot and a 96-well competitive ELISA.

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