Title: stopped flow
Long Title: IUPAC Gold Book - stopped flow
DOI: 10.1351/goldbook.S06033
Status: current

Definition
A technique for following the kinetics of reactions in solution (usually in the millisecond time range) in which two reactant solutions are rapidly mixed by being forced through a mixing chamber. The flow of the mixed solution along a uniform tube is then suddenly arrested. At a fixed position along the tube the solution is monitored (as a function of time following the stoppage of the flow) by some method with a rapid response (e.g. photometry).

Related Terms
- mixing control: https://goldbook.iupac.org//terms/view/M03946
- photometry: https://goldbook.iupac.org//terms/view/P04625

Sources
- PAC, 1993, 65, 2291. 'Nomenclature of kinetic methods of analysis (IUPAC Recommendations 1993)' on page 2298 (https://doi.org/10.1351/pac199365102291)
- PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1168 (https://doi.org/10.1351/pac199466051077)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/S06033/html
- json: https://goldbook.iupac.org/terms/view/S06033/json
- xml: https://goldbook.iupac.org/terms/view/S06033/xml

Citation: Citation: 'stopped flow' 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.S06033
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Accessed: 2026-05-09T14:09:08+00:00