Title: catalytic activity concentration
Long Title: IUPAC Gold Book - catalytic activity concentration
DOI: 10.1351/goldbook.C00882
Status: current

Definition
Catalytic activity of the component divided by the volume of the system.

Notes
1) In clinical chemistry litre is recommended as unit for the volume.
2) In clinical chemistry the component is usually an enzyme.
3) The term 'catalytic concentration' is accepted for use in clinical chemistry.
4) Use of the term level as a synonym for concentration is deprecated.
5) In describing a quantity, concentration must be clearly differentiated from content.

Related Terms
- concentration: https://goldbook.iupac.org/terms/view/C01222
- content: https://goldbook.iupac.org/terms/view/C01296
- litre: https://goldbook.iupac.org/terms/view/L03594

Source
- PAC, 1996, 68, 957. 'Glossary of terms in quantities and units in Clinical Chemistry (IUPAC-IFCC Recommendations 1996)' on page 964 (https://doi.org/10.1351/pac199668040957)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/C00882/html
- json: https://goldbook.iupac.org/terms/view/C00882/json
- xml: https://goldbook.iupac.org/terms/view/C00882/xml

Citation: Citation: 'catalytic activity concentration' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.C00882
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Accessed: 2026-05-14T21:02:34+00:00