DPPH free radical is a very stable nitrogen-centered free radical. It is one of the important indicators of the
sample's antioxidant capacity and is widely used in the research of antioxidant foods, health products and
pharmaceuticals.
The DPPH radical has a single electron, and its alcohol solution is purple, with strong absorption at 515
nm. When an antioxidant present, DPPH free radicals are cleared, the solution color becomes lighter, and
the absorbance at 515 nm decreases. Within a certain range, the change in absorbance is directly
proportional to the degree of free radical removal. In this kit, the ability of the sample to remove DPPH
free radicals is reflected by the degree of decrease in absorbance.
Reagents and Equipment Required but Not Provided.
Spectrophotometer, water bath, centrifuge, 1mL glass cuvette, motor/ grinder, absolute ethanol, oven, 30-
50 mesh sieve and distilled water.