Used in metabolic research to study fatty acid oxidation and energy metabolism, particularly in the context of mitochondrial function. It serves as a stable isotope-labeled tracer in mass spectrometry-based assays, enabling precise quantification of carnitine and acylcarnitine levels in biological samples. Applied in clinical diagnostics to investigate metabolic disorders like carnitine deficiency or fatty acid metabolism defects. Also utilized in pharmaceutical studies to evaluate drug effects on lipid metabolism and mitochondrial activity. Its deuterated form ensures accurate tracking in complex biological systems.