Used primarily in biochemical assays to detect the presence of superoxide radicals. It reacts with these radicals to form an insoluble formazan dye, which can be measured spectrophotometrically. Commonly employed in the NBT reduction test to assess the oxidative burst in phagocytic cells, such as neutrophils and macrophages. Also utilized in histochemistry and cytochemistry to localize enzyme activity, particularly in tissues and cells. Applied in plant biology to study reactive oxygen species (ROS) production during stress responses. Frequently used in microbiology to evaluate the metabolic activity of microorganisms. Its ability to form a visible precipitate makes it valuable in visualizing and quantifying oxidative processes in various biological systems.