Analysis of Demicellization Data from Isothermal Titration Calorimetry

This whitepaper outlines how two different approaches can be combined to provide a data-analysis strategy of superior reproducibility and without user bias, as the only user input required is the calorimetric dataset itself. Many industrial and biochemical applications depend on the usage of detergents and other surfactants. These compounds are indispensable, in particular, for the extraction, purification, and handling of membrane proteins. Owing to their amphiphilic nature, detergents can provide a membrane-mimetic environment required by integral membrane proteins to retain their native structures and functions in aqueous solution. The CMC is one of the most fundamental characteristics of a surfactant. In aqueous solutions, surfactants form colloidal aggregates, so-called micelles, when their concentration exceeds the CMC. To obtain the CMC in an accurate and precise manner, however, isothermal titration calorimetry (ITC) is the method of choice, which is due to its extraordinary sensitivity, unsurpassed resolution, and high reproducibility.