Title: katal
Long Title: IUPAC Gold Book - katal
DOI: 10.1351/goldbook.K03372
Status: current
Index: unit

Definition
Unit for catalytic activity coherent with the SI, equal to the catalytic activity that catalyses a reaction rate of one mole per second in an assay system. \(\pu{1 kat} = \pu{1 mol s-1}\). The katal is recommended for use in the specific context of enzymes and clinical chemistry.

Related Terms
- assay: https://goldbook.iupac.org/terms/view/A00470
- enzymes: https://goldbook.iupac.org/terms/view/E02159
- mole: https://goldbook.iupac.org/terms/view/M03980

Source
- PAC, 1996, 68, 957. 'Glossary of terms in quantities and units in Clinical Chemistry (IUPAC-IFCC Recommendations 1996)' on page 977 (https://doi.org/10.1351/pac199668040957)

Related Reference
- PAC, 1994, 66, 2587. 'Glossary of bioanalytical nomenclature - Part 1: General terminology, body fluids, enzymology, immunology (IUPAC Recommendations 1994)' on page 2595 (https://doi.org/10.1351/pac199466122587)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/K03372/html
- json: https://goldbook.iupac.org/terms/view/K03372/json
- xml: https://goldbook.iupac.org/terms/view/K03372/xml

Citation: Citation: 'katal' 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.K03372
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Accessed: 2026-05-14T17:21:48+00:00