Did you know that you can measure the antioxidant capacity of foods and supplements with the help of a fluorescence assay?
Antioxidants are able to catch and to disarm radicals. This can be tested if a radical generator is active in the presence of a fluorescent dye, like fluorescein. Without any protection of an antioxidant the radicals will destroy the fluorescent dye which can be seen by a decreasing fluorescence signal over time. If a known antioxidant is added to the reaction it will prevent the fluorescent dye from degrading so fast. A sample of unknown antioxidant potential can be measured the same way and the result can be related to the standard value.