Used as a stable isotope-labeled internal standard in mass spectrometry-based bioanalytical assays for quantifying glucuronide metabolites in biological matrices such as plasma, urine, and tissue extracts. Its primary application is in pharmacokinetic and metabolic studies where accurate measurement of drug glucuronidation is required. The deuterated form ensures minimal interference from endogenous compounds, enabling high specificity and sensitivity in LC-MS/MS detection. Commonly employed in drug development to assess the metabolic stability and clearance pathways of compounds undergoing phase II metabolism.