Used primarily in medical and pharmacological research as a stable isotope-labeled compound (deuterated form of 4-aminohippuric acid), it serves as a tracer in studies related to kidney function. It helps in measuring effective renal plasma flow (ERPF) and assessing the efficiency of the kidneys in clearing substances from the blood via tubular secretion. Additionally, it is employed in metabolic studies to track the distribution and excretion of compounds, providing insights into drug metabolism and pharmacokinetics. Its deuterated form enhances precision in analytical techniques like mass spectrometry, ensuring accurate and reliable results in complex biological samples.