The Superoxide Dismutase (SOD) Activity Assay utilizes WST-1 to assess SOD activity in biological samples. SOD is an enzyme that catalyzes the dismutation of the superoxide (O2-) anion radical into molecular oxygen (O2) and hydrogen peroxide (H2O2). This assay indirectly determines the activity of SOD by using WST-1 to measure the superoxide O2- levels in samples, which would be suppressed when SOD activity is high. WST-1 interacts with superoxide O2- to form a colored product which can be measured spectrophotometrically at an absorbance of 440 nM.