Used primarily as a stable isotope-labeled internal standard in mass spectrometry-based bioanalytical assays. Enables accurate quantification of N-methyltryptamine and related tryptamines in biological matrices such as plasma, urine, and brain tissue. Its deuterated structure allows clear differentiation from endogenous compounds, improving measurement specificity and reliability in pharmacokinetic and metabolic studies. Also applied in neuroscience research to trace metabolic pathways and study the dynamics of trace amines in the central nervous system.