Used as a stable isotope-labeled internal standard in analytical chemistry for the accurate quantification of N-nitrosodimethylamine (NDMA) in various matrices such as pharmaceuticals, environmental samples, and food products. Its primary application is in mass spectrometry and gas chromatography-mass spectrometry (GC-MS) workflows, where it corrects for matrix effects, instrument variability, and losses during sample preparation. Due to its deuterated structure, it behaves similarly to the target analyte during extraction and separation but is distinguishable by mass detection, enabling precise and reliable measurement of NDMA levels, especially in regulatory and quality control settings.