Term: mixed labelled
https://doi.org/10.1351/goldbook.M03943

Definition:
A specifically labelled compound is referred to as mixed labelled when the isotopically substituted compound has more than one kind of modified atom e.g. CH3–CH2–[18O][2H].

Related Terms:
1) specifically labelled (http://doi.org/10.1351/goldbook.S05793).
2) isotopically substituted (http://doi.org/10.1351/goldbook.I03338).

Source: Blue Book, p. 515 (https://www.acdlabs.com/iupac/nomenclature/)

Citation: 'mixed labelled' 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.M03943

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