1-Naphthyl phosphate is widely used as a substrate in enzymatic assays, particularly in the detection of alkaline phosphatase activity. It serves as a key component in biochemical research and diagnostic kits, where the enzyme cleaves the phosphate group, producing 1-naphthol. This product can then react with a diazonium salt to form a colored compound, enabling the quantification of enzyme activity. Its application is essential in medical diagnostics, such as liver function tests, and in research settings to study enzyme kinetics and cellular processes. Additionally, it is utilized in histochemistry for staining tissues to visualize enzyme distribution.