What is FRAP assay used for?

What is FRAP assay used for?

A simple, automated test measuring the ferric reducing ability of plasma, the FRAP assay, is presented as a novel method for assessing “antioxidant power.” Ferric to ferrous ion reduction at low pH causes a colored ferrous-tripyridyltriazine complex to form.

What is FRAP method?

The ferric reducing antioxidant power (FRAP) assay is a typical ET-based method that measures the reduction of ferric ion (Fe3+)-ligand complex to the intensely blue-colored ferrous (Fe2+) complex by antioxidants in an acidic medium.

What is the role of Fe3+ in the FRAP assay?

Ferric reducing antioxidant power (FRAP) assay is a widely used method that uses antioxidants as reductants in a redox-linked colorimetric reaction, wherein Fe3+ is reduced to Fe2+ .

What is reducing power assay?

Reducing power assay method is based on the principle that substances, which have reduction potential, react with potassium ferricyanide (Fe3+) to form potassium ferrocyanide (Fe2+), which then reacts with ferric chloride to form ferric–ferrous complex that has an absorption maximum at 700 nm.

What is the standard for FRAP assay?

Standards. Ascorbic acid was used as a standard for DPPH-free radical scavenging assay and for reducing power assay. Trolox and ascorbic acid served as two standards for ABTS scavenging assay and ferrus sulphate for FRAP assay. For total phenol content calculation, gallic acid was used as the standard.

What is the principle of ferric reducing antioxidant power FRAP assay?

Ferric reducing ability of plasma (FRAP) assay is based on the principle of reduction of ferric-tripyridyltriazine (Fe3+-TPTZ) complex to ferrous tripyridyltriazine (Fe2+-TPTZ) by the antioxidants of a sample at low pH [12].

What is reducing power in antioxidant activity?

What is the meaning of reducing power?

Reducing power is the potential of a substance to reduce another substance. That can be either by addition or removal of hydrogen or by loss or gain of electrons.

How is antioxidant strength measured?

ORAC Assay (The Oxygen Radical Absorbance Capacity) ORAC assay is a method for quantifying the antioxidant strength of substances. It involves combining the sample to be tested (i.e. the antioxidant) with a fluorescent compound as well as a compound that generates free radicals at a known rate.

How is antioxidant ability measured?

Many popular methods to assess antioxidant activity are based on the competitive reaction of radicals with the antioxidant or with a probe, whose transformation can be monitored by fluorimetry (e.g., the ORAC assay), by spectrophotometry (e.g., the crocin bleaching assay), EPR (e.g., spin-trapping methods), or other …

How do you calculate antioxidant capacity?

Total antioxidant capacity (Ta) was calculated with the equation Ta = 100/(OD1 + 2 * OD2 + 2 * OD3 + 2 * OD4 + OD5), and average activity (A) was calculated as A = Ta/M. Results.

What is ORAC value?

The ORAC unit (Oxygen Radical Absorbance Capacity), ORAC value, or ORAC score is a method developed by scientists at the National Institute of Health and Aging (NIH) to measures the antioxidant capacity of different foods.

What is reduction power?

What does reducing power depend on?

-The reduction potential of any metal depends on various factors like: -Sublimation enthalpy: Energy required in converting one mole of solid substance into gaseous state. -Ionisation enthalpy: Energy required in removing an electron from the outermost shell of an isolated gaseous atom.

What is antioxidant capacity?

Total antioxidant capacity (TAC) is the measure of the amount of free radicals scavenged by a test solution [4], being used to evaluate the antioxidant capacity of biological samples [3, 6, 7].