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Measured directly?

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"ITC is a quantitative technique that can directly measure the binding affinity (Ka), enthalpy changes (ΔH), and binding stoichiometry (n) of the interaction between two or more molecules in solution."

I'm not sure it's fair to call these direct measurements. It's fairly uncontroversial to obtain them from ITC, but the instrument is basically just a calorimeter. The only primary data obtained is heat change/flow (ie enthalpy). Just because the software that runs the instrument reports these three things up front doesn't mean they're being directly measured. I know it may sound like a semantic argument, but the way it's written now it makes it sound like they're direct measurements. I(q) = User(q)·Talk(q) 21:44, 31 August 2011 (UTC)[reply]

Yes, only the reaction enthalpy is measured directly. Kbuessow (talk) 10:28, 29 November 2022 (UTC)[reply]

Figure ITC thermogram

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The figure suggests that the slope of the curve corresponds to the Ka value. That can't be true. I am also not sure that the 'midpoint' exactly corresponds to the stoichiometry. These labels are misleading because Ka and stoichiometry are determined in a completely different way. The are derived by curve fitting the whole thermogram according to the law of mass action. — Preceding unsigned comment added by Kbuessow (talkcontribs) 10:35, 29 November 2022 (UTC)[reply]

Wiki Education assignment: Functional Nanomaterials

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This article was the subject of a Wiki Education Foundation-supported course assignment, between 4 January 2023 and 7 March 2023. Further details are available on the course page. Student editor(s): EnthalpicallyUnfavorable (article contribs).

— Assignment last updated by EnthalpicallyUnfavorable (talk) 21:19, 17 January 2023 (UTC)[reply]

Hello, as I am planning to edit this article as a part of my class project, I want to write roughly about what I would add and edit in this page.
This is a short article about isothermal titration calorimetry (ITC). The content of this article is all relevant to the topic and written in a neutral manner. One downside is that the application section is very brief and probably outdated. In terms of references and citations, all the links are still working properly. However, there are only four references as of January 17th, 2023 and a number of citations is missing throughout the page. I plan to edit this page as a part of my class project, by adding more information and possibly 20 to 30 more references on top of what is already existing.
ITC is widely used in numerous research fields to determine metal binding thermodynamics, surfactant aggregation, enzyme kinetics, etc.. We can probably add more recent references and information for the drug discovery topic as well, as the cited review article is from a decade ago. Additionally, adding how to go around the c-window limitation by conducting competition or chelation experiments, and the importance of reaching injection equilibrium would further strengthen the instrumental section. A method of doing post-hoc analysis by applying basic Hess’ Law to deduce buffer or solvent-free thermodynamics would be beneficial as well, as the observed thermodynamic value contains multiple chemical interactions (ligand-solvent interaction, buffer-proton interaction, etc.). Proton inventory would also be useful.
Lastly, I aim to add a couple sections that are connecting this article to other pages. First of them would be about history: how isothermal titration calorimetry is developed by H. D. Johnston at Brigham Young University, and enhancement of the technique to acknowledge individual contributions and advances in the field. Secondly, limitations of this technique and how it can be used with other techniques, such as differential scanning calorimetry would be useful, if there are any chemists on Wikipedia who want to explore different techniques related or similar to ITC.
This article has a huge potential for improvements and I am very excited to contribute to this article, as I use this technique on daily basis. If there are any more suggestions, please leave a reply! EnthalpicallyUnfavorable (talk) 17:06, 18 January 2023 (UTC)[reply]
Hello again! I have added and changed a few things from what I have mentioned above and I want to list them here.
1. Added a paragraph about history of ITC at introduction section
2. Added a paragraph regarding the c-window range explaining in terms of binding affinity and a brief sentence of how the integrated plot is made from the raw data.
3. Added a paragraph explaining tips for troubleshooting limitations of c-window, and reaching injection equilibria.
4. A section about data interpretation added, including equilibrium constant, buffer-free thermodynamics calculation, and proton inventory.
5. 2 figures added: How a typical ITC instrument looks like (VP-ITC from MicroCal Inc. used as an example), and how a proton inventory plot looks like.
6. Extended application section: chiral chemistry, enzyme kinetics, metal binding interactions, carbon nanotube and graphite, peptide self-assembly, etc.
7. Removed about 4 references during the edit, and replaced them with more up-to-date or well-cited journal articles or sources. Total of 23 references added.
EnthalpicallyUnfavorable (talk) 15:31, 22 February 2023 (UTC)[reply]