Algorithms in the AFFINImeter software allow kinetic information to be extracted from experimental ITC data.
This application note from Malvern Panalytical describes how to determine if your ITC data contains kinetic information, and how to extract kinetic parameters such as kon and koff.
Kinetic Data from ITC
Isothermal titration calorimetry (ITC) is a thermodynamic technique, which is generally believed to be unsuitable for obtaining kinetic information. Other proven techniques such as SPR (surface plasmon resonance) are typically preferred for kinetic studies.
However, ITC is indeed based on kinetic measurements, and the raw signal in any ITC experiment is the rate of heat production in the reaction. Because there is a direct relationship between this heat power signal and the reaction kinetics, ITC microcalorimeters have the potential to capture kinetic data, as well as acting as a "heat-meter".
This article discusses how and when kinetic data can be obtained from ITC power curves using the MicroCal ITC200 instrument with a response time of 3.5s. The algorithms used to generate these results are available in AFFINImeter.
MicroCal ITC2000 from Malvern Panalytical
Results and Conclusion
In this application note, the simplified ETC-based kinITC technique was shown to be effective for obtaining kinetic data as well as valuable thermodynamic information. The elimination of the sample preparation step is the key advantage of the kinITC technique, making it a true ‘label-free’ and ‘in-solution’ method.
The introduction of the underlying algorithms into AFFINImeter enables kinetic parameters to be obtained immediately after the processing of the raw injection curves.
References
- "Implementation of kinITC into AFFINImeter", Philippe Dumas, Eric Ennifar, Guillaume Bec, Angel Piñeiro, Juan Sabn, Eva Muños, Javier Rial - Malvern Panalytical Application Note
- "Get more out of ITC data", Philippe Dumas. kinITC - recorded Malvern Panalytical webinar
- "A new method for obtaining joint thermodynamic and kinetic data by isothermal titration calorimetry" - Burnouf, D., et al, kinITC, J Am Chem Soc, 2012, DOI: 10.1021/ja209057d
- "Extending ITC to kinetics with kinITC" - Philippe Dumas, Eric Ennifar, Cyrielle Da Veiga, Guillaume Bec, William Palau, Carmelo Di Primo, Angel Piñeiro, Juan Sabin, Eva Muñoz, Javier Rial in Methods in Enzymology Vol 567, A. Feig Editor. (release 18 Jan 2016)
This information has been sourced, reviewed and adapted from materials provided by Malvern Panalytical.
For more information on this source, please visit Malvern Panalytical.