Multithermal titration calorimetry: A rapid method to determine binding heat capacities

• Published in: Biophysical chemistry Vol. 120; no. 1; pp. 10 - 14
• Main Authors: Chavelas, Eneas A., Zubillaga, Rafael A., Pulido, Nancy O., García-Hernández, Enrique
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.03.2006
• Subjects: Algorithms; Binding energetics; Calorimetry - methods; Feasibility Studies; Isothermal titration calorimetry; Macromolecular Substances - chemistry; Macromolecular Substances - metabolism; Models, Chemical; Molecular recognition; Temperature; Thermodynamics; Time Factors; Molecular recognition; Binding energetics; Isothermal titration calorimetry
• ISSN: 0301-4622; 1873-4200
• DOI: 10.1016/j.bpc.2005.09.022

Herein a new method that allows binding ΔCp to be determined with a single experiment is presented. Multithermal titration calorimetry (MTC) is a simple extension of isothermal titration calorimetry (ITC) that explicitly takes into account the thermal dependences of Δ H and the binding constant. Experimentally, this is accomplished by performing a single stepwise titration with ITC equipment, allowing temperature re-adjustments of the system at intermediate states of the titration process. Thus, from the resulting multitherm, ΔCp can also be determined. The experimental feasibility of MTC was tested by using the well-characterized lysozyme–chitotriose complex as a model system.