Complex isotope-labeled products are sophisticated chemical compounds tagged with stable or radioactive isotopes, playing a pivotal role in cutting-edge research and industrial applications. These products enable the precise tracing and quantification of molecular interactions, metabolic pathways, and environmental processes. By incorporating specific isotopes, they allow researchers to track chemical reactions and biological processes with exceptional accuracy. Widely used in mass spectrometry, NMR spectroscopy, and pharmacokinetics, these labeled compounds are essential for advancing our understanding of complex systems and driving innovation in fields like biochemistry, environmental science, and drug development.