Chloramphenicol D5, a deuterated form of chloramphenicol, is primarily used as an internal standard in analytical chemistry, particularly in mass spectrometry. Its application is crucial for ensuring accurate quantification and identification of chloramphenicol in various samples, such as biological fluids, food products, and environmental samples. By serving as a stable isotope-labeled reference, it helps correct for variations in sample preparation and instrument performance, enhancing the reliability of analytical results. This is especially important in regulatory and research settings where precise measurement of chloramphenicol levels is required to monitor antibiotic residues, assess contamination, or study pharmacokinetics.