Stopped-flow method
The term stopped-flow method or flow- interrupting analysis describes a method for the kinetic investigation of fast chemical reactions, which was developed in 1937 by Britton Chance .
execution
The basic form of the technology consists of a mixing chamber into which two gases or reaction solutions are pressed and mixed, and a cell in which the course of the chemical reaction can be followed using suitable means. For example, spectroscopic techniques such as fluorescence spectroscopy or circular dichroism are used as analytical methods .
The name of the method comes from the fact that the flow of the solutions mixed in the mixing chamber is interrupted by closing a valve. The change in the spectrum is recorded over time and serves as a measure of the progress of the reaction.
The scope of the method is mainly determined by the mixing time of the reactants . The response times achieved are in the range of milliseconds. In the case of liquids, the method can only be used to a limited extent, since the time of filling and a reaction disturbance immediately after the valve has been shut off represent barriers to the measurement.
Individual evidence
- ↑ Britton Chance: The stopped-flow method and chemical intermediates in enzyme reactions - a personal essay in: Photosynthesis Research 80: 387–400, 2004 (PDF; 392 kB)
- ^ WJ Moore; DO Hummel: Physical Chemistry. Berlin; New York: de Gruyter, 1986, ISBN 3110109794 , page 382.
literature
- WJ Moore; DO Hummel: Physical Chemistry. Berlin; New York: de Gruyter, 1986, ISBN 3110109794 , pages 381 f.
Web links
- Entry on stopped flow . In: IUPAC Compendium of Chemical Terminology (the “Gold Book”) . doi : 10.1351 / goldbook.S06033 Version: 2.3.3.