DetectX® FRAP™ (Ferric Reducing Antioxidant Power) Detection Kit

 Arbor Assay's FRAP Detection Kit

• Background about Reactive Oxygen Species
• About Ferric Reducing Antioxidant Power Assay
• DetectX® FRAP™ Colorimetric Detection Kit
• Resources
• Publications

Background about Reactive Oxygen Species


Figure (1): ROS mediated activation of cell signaling pathways

Reactive oxygen species (ROS) are produced as a consequence of normal aerobic metabolism. These ''free radicals'' (FR) are usually removed or converted into other products in vivo by an array of antioxidants. Antioxidants are typically chemically stable atoms and molecules, which have one (or rarely more) free electron/electrons in their electron envelope. Almost all biomolecules, but mainly biomembranes, proteins and nucleic acids, may be attacked by reactive free radicals. Free radicals are responsible for many pathological processes, or they can be generated as the result of the pathological stage and cause important secondary damage to biological systems and cells. Connections between free radicals and some serious diseases, including Parkinson's and Alzheimer's diseases, atherosclerosis, myocardial infarction, and chronic fatigue syndrome, have been demonstrated. However, short-term oxidative stress, the unbalance between the formation and scavenging of the reactive oxygen species, may be important in the prevention of aging due to triggering the process known as mitohormesis. On the average, 65–70 % of the population is excessively impacted by oxidative stress caused by FRs.

In 1996 Iris Benzie and Sean Strain published a simple assay to measure antioxidant power. The original demonstration of the power of this assay to measure antioxidant potential in serum and plasma has been extended to the antioxidant power of certain foods, teas, and fungi.

The protective system of organisms is based on the activity of specific enzymes (especially superoxide dismutase, glutathione peroxidase, catalase, glutathione reductase) as well as non-enzymatic compounds with antioxidant activity (ß-tocopherol, L-ascorbic acid, glutathione, coenzyme Q10, flavonoids, albumin and other molecules). Excess production of reactive oxygen species can also lead to inflammation, premature aging disorders, and several disease states, including cancer, diabetes, and atherosclerosis. Organisms have developed complex antioxidant systems to protect themselves from oxidative stress, however, excess ROS can overwhelm the systems and cause severe damage.

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About Ferric Reducing Antioxidant Power Assay

Ferric Reducing Antioxidant Power  (FRAP) principle

One of the most important methods of quantitating antioxidant status is the Ferric Reducing Ability of Plasma (FRAP™) assay.

The FRAP assay was described by Iris Benzie and Sean Strain in 1996. It utilizes a ferric ion complex with tripyridyltriazine (TPTZ), where the Fe(III) species is reduced to Fe(II) by antioxidants, forming an intense blue color with an absorption maximum at 593 nm. This patented assay has been used to establish the antioxidant status of a large number of foods, drinks, and herbs. It has also been applied to the antioxidant capacity of serum and plasma samples.

Arbor Assay's DetectX® FRAP™ Colorimetric Detection Kit (Cat#: K043-H1), provides a stable assay kit, licensed exclusively from the Hong Kong Polytechnic University and Dr. Benzie.

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DetectX® FRAP™ Colorimetric Detection Kit

The DetectX® Ferric Reducing Antioxidant Power (FRAP™) Detection Kit is designed to quantitatively measure antioxidant status in a variety of samples. The assay measures the antioxidant ability from all species.

A Ferrous Chloride 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 the provided Assay Buffer and added to the wells. The FRAP Color Solution is made by mixing Reagent A and B with Assay Buffer. The FRAP Color Solution is added to all wells and the plate incubated at room temperature. Antioxidant power in the samples reacts with the FRAP Color Solution to generate a blue colored product which is read at 560 nm.

  • USE: Measure FRAP in 30 Minutes
  • SAMPLE TYPE:Serum, Plasma, Urine, Foods, Cosmetics, etc.
  • SENSITIVE: Measure < 6 µM Fe2+
  • STABLE: 4°C
  • LICENSED: Exclusive License to Patented Technology
  • SAMPLES/KIT: 89 in Duplicate
Item Catalog # Download
FRAP™ (Ferric Reducing Antioxidant Power) Detection Kit K043-H1 Product Manual

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• Original Scientific Paper of FRAP assay: Benzie, IFF, and Strain, JJ, "The Ferric Reducing Ability of Plasma (FRAP) as a Measure of ''Antioxi dant Power'': The FRAP Assay", Anal. Biochem, 1996, 239:70-76.
• Product Manual


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Publications Cited our FRAP Assay

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