Non-Esterified Fatty Acids (NEFA/FFA)
Used for the quantitative determination of determination of NEFA in EDTA plasma and serum on the Beckman Coulter UniCel DxC600 Synchron Clinical System by an adaptation of the Randox method using the Randox NEFA reagent kit.
Instrument: Beckman Coulter UniCel DxC600
Specimen Type: EDTA plasma & serum
Volume per test: 5uL EDTA plasma (min volume 100uL), 200uL serum (min volume 300uL)
Principle:
Non-esterified fatty acids in plasma, when treated with acyl-CoA synthethase (ACS) in the presence of adenosine triphosphate (ATP), magnesium cations and coenzyme A (CoA), form thiol esters of CoA known as acyl-CoA as well as the byproducts adenosine monophosphate (AMP) and pyrophosphate (Ppi). In the second step, Acyl-CoA is oxidized by added acyl-CoA oxidase (ACOD) to produce hydrogen peroxide. Hydrogen peroxide in the presence of added peroxidase (POD) allows the oxidative condensation of 3-methyl-N-ethyl- (β-hydroxyethyl)-aniline (MEHA) with 4-aminoanti-pyrine to form a purple coloured adduct with an absorption maximum at 550 nm. Endogenous Ascorbic acid (vitamin C) in the sample would be expected to cause significant interference due to its biological role as an antioxidant and known ability to react with hydrogen peroxide. Therefore ascorbate oxidase (AOD) is added to the reaction mixture at the outset to conveniently and completely remove all ascorbic acid from the sample.
Testing Range: 56-2000 umol/L (EDTA plasma) / 42-2000 umol/L (serum)