VA(Vitamin A) ELISA Kit (E-EL-0135)

This ELISA kit uses the Competitive-ELISA principle. The micro ELISA plate provided in this kit has been pre-coated with Universal VA. During the reaction, Universal VA in the sample or standard competes with a fixed amount of Universal VA on the solid phase supporter for sites on the Biotinylated Detection Ab specific to Universal VA. Excess conjugate and unbound sample or standard are washed away, and Avidin-Horseradish Peroxidase (HRP) conjugate are added to each micro plate well and incubated. Then a TMB substrate solution is added to each well. The enzyme-substrate reaction is terminated by the addition of stop solution and the color turns from blue to yellow. The optical density (OD) is measured spectrophotometrically at a wavelength of 450 nm ± 2 nm. The concentration of Universal VA in tested samples can be calculated by comparing the OD of the samples to the standard curve.

Vitamin A is a fat soluble vitamin mainly found in animal foods such as egg yolks, butter, or liver, as well as in certain green or orange vegetables such as carrots and spinach. Its deficiency can lead to thickening of keratin tissue, such as retinal lesions in the eyes. There are two forms of vitamin A, one is retinol, which is mainly present in animal food; Another type is carotene, a precursor substance that is converted into vitamin A in the body and can be consumed from plant-based and animal based foods. In addition, vitamin A, also known as retinol, is an unsaturated monohydric alcohol with a lipid ring, including vitamins A1 and A2 from animal food sources. Among them, vitamin A1 is mainly present in the liver, blood, and retina of animals, and vitamin A2 is mainly present in freshwater fish