Used as a deuterated internal standard in mass spectrometry and nuclear magnetic resonance (NMR) analysis to accurately quantify adipic acid and related compounds in complex mixtures. Its fully deuterated structure provides a distinct mass shift, minimizing interference from non-labeled compounds, making it valuable in metabolic studies, environmental analysis, and quality control in polymer manufacturing. Also employed in kinetic and mechanistic studies where isotopic labeling helps track reaction pathways without altering chemical behavior.