Cefazolin-13C2,15N is primarily used as a stable isotope-labeled compound in research and analytical studies. It serves as an internal standard in mass spectrometry for the accurate quantification of cefazolin in biological samples, such as blood or urine. This labeled version helps improve precision and reliability in pharmacokinetic studies, enabling researchers to track drug metabolism and distribution in the body. Additionally, it aids in the development of robust analytical methods for quality control in pharmaceutical manufacturing. Its use ensures minimal interference from non-labeled compounds, enhancing the accuracy of experimental results.