isotopic label

mentioned: conjugation labelling, exchange labelling, recoil labelling
https://doi.org/10.1351/goldbook.08733
Radioactive or stable isotope of a specified element distinguishable by the observer but not by the system used to identify an isotopic tracer.

Notes:

  1. 'Isotopic labelling' is the incorporation of an isotopic label in a substance. It may be qualified by the manner of introduction of the label, e.g. exchange labelling, conjugation labelling, recoil labelling.
    Examples: Deuterium ('isotopic label') that is substituted for protium in the illegal drug methylamphetamine, for use in analysis by mass spectrometry. Methylamphetamine incorporating deuterium is the 'isotopic tracer'.Example:

  2. In general usage, 'label' and 'tracer' are used synonymously.

Source:
PAC, 2021, 93, 69. (Vocabulary of radioanalytical methods (IUPAC Recommendations 2020)) on page 85 [Terms] [Paper]
Citation: 'isotopic label' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.08733 RIS BibTex EndNote
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