Dehydroascorbic Acid/Ascorbic Acid (DHA/AsA) Content Fluorometric Assay Kit

Ascorbic acid(AsA) is one of the primary antioxidants in living organisms. It can directly scavenge free radicals， protecting cell membranes and DNA from oxidative damage. Furthermore， as a cofactor for various hydroxylases， AsA is essential for physiological processes such as collagen synthesis and neurotransmitter metabolism. Dehydroascorbic acid (DHA) is the oxidation form of AsA and can be recycled back to AsA through reducing systems such as the glutathione-dependent pathway. The AsA/DHA ratio serves as a critical indicator for evaluating oxidative stress levels， antioxidant capacity， and the functional status of cells. DHA reacts with o-phenylenediamine to form a quinoxaline derivative. Its fluorescence intensity at the excitation wavelength of 338 nm and the emission wavelength of 420 nm is proportional to the DHA content. AsA is oxidized to DHA by an oxidizing agent. The total ascorbic acid content (AsA+DHA) can be measured， allowing the AsA concentration to be calculated by difference.