Used in research and development as a labeled compound for studying the pharmacokinetics and metabolism of chloroquine. It serves as an internal standard in mass spectrometry for accurate quantification of chloroquine in biological samples. Applied in drug metabolism studies to track the distribution and elimination of chloroquine in the body. Also utilized in clinical research to investigate the efficacy and safety of chloroquine-based treatments. Helps in understanding drug interactions and resistance mechanisms in malaria research.