Used as a chromogenic substrate in immunohistochemistry and Western blotting for the detection of enzyme activity, particularly with alkaline phosphatase. It produces a blue-purple insoluble precipitate upon reaction, allowing visualization of target proteins or antigens. Its ready-to-use formulation simplifies laboratory workflows by eliminating the need for solvent preparation, improving consistency and reducing exposure to hazardous solvents. Commonly applied in research and diagnostic settings for high sensitivity and clear contrast in membrane-based assays.