Active oxygen such as superoxide anion in the living body has the functions of immunity and signal
transduction. But if it accumulates too much, it will destroy the cell membrane and biomacromolecules,
leading to abnormal metabolism of the cells and tissues of the body, and cause many diseases.
The superoxide anion reacts with hydroxylamine hydrochloride to form NO2-, and the NO2- under the
action of p-aminobenzenesulfonamide and naphthalene ethylenediamine hydrochloride is produced a red
azo compound with a characteristic absorption peak at 530 nm. The content of O2- can be calculated
according to the A530 value.
Reagents and Equipment Required but Not Provided:
Spectrophotometer/Microplate reader, water-bath, balance, mortar/homogenizer, centrifuge, micro glass
cuvette/96 well flat-bottom plate, chloroform and distilled water.
Sample preparation:
1. Plant and animal tissues: Weigh about 0.1 g of sample, add 1 mL of Extract solution and fully grind.
Centrifuge at 12000 rpm for 20 min at 4°C, then take 20 μL of supernatant to determine protein
content, and the other supernatants as samples to be tested.
2. Serum or culture medium: detect directly.
