Used primarily as a substrate in biochemical assays, particularly in enzyme-linked immunosorbent assays (ELISAs) and immunohistochemistry. It serves as a chromogenic indicator for alkaline phosphatase activity, producing a detectable color change when the enzyme cleaves the phosphate group. This property makes it valuable in medical diagnostics and research for detecting specific proteins or antibodies. Additionally, it is employed in histology to visualize tissue samples under a microscope, aiding in the study of cellular structures and disease markers.