Katal

The SI derived unit of catalytic activity, equal to one mole of substrate converted per second. It measures an enzyme or catalyst’s rate of substance conversion.

Catalytic activity: The rate at which a catalyst converts a specified chemical substance in a defined reaction. Katal is the SI unit used to quantify this rate.
Enzyme assay: A laboratory procedure that measures an enzyme’s activity under specified conditions. Assays determine the substrate-conversion rate expressed in katals.
International Union of Pure and Applied Chemistry: An international organization that develops standards and recommendations for chemistry. IUPAC recommended the katal as a coherent unit for catalytic activity.
Clinical chemistry: The branch of laboratory medicine that analyzes chemical substances in body fluids for diagnosis and monitoring. Clinical laboratories measure enzyme activities, though commonly using smaller units.
Mole: The SI unit for amount of substance, defined by exactly 6.02214076 × 10²³ specified entities. The katal’s numerator is one mole of converted substance.
Reaction rate: The change in concentration or amount of a reactant or product per unit time. Katal expresses a reaction rate as amount converted per time.
International Bureau of Weights and Measures: The international organization that coordinates the SI and global measurement standards. Its SI documentation recognizes the katal as a derived unit.
Lactate dehydrogenase: An enzyme that catalyzes interconversion of lactate and pyruvate while transferring electrons through NAD⁺ and NADH. Its activity is measured in enzyme assays and can be expressed in katals.
Second: The SI base unit of time, defined by the caesium-133 hyperfine transition frequency. The katal expresses catalytic activity per second.
Substrate (biochemistry): A molecule on which an enzyme acts to produce reaction products. The katal definition counts the amount of substrate converted.

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SI derived unitBroader topic: It measures the rate of conversion of chemical amount.