Isothermal titration Calorimetry (ITC) is a powerful tool used to determine the thermodynamics of a particular reaction between two molecules. ITC experiments are performed at constant temperature by titrating one binding partner (the titrant) into a solution containing the other partner (the titrand). After each aliquot of titrant is added, the heat absorbed or released by its reaction with the titrand is measured with respect to a reference cell containing buffer. The heat change is measured in electrical power (J/s) as it is the difference in power needed to maintain the sample and reference cells at two similar temperatures.
Information Available from ITC: Binding Constant (Kb), Reaction Stoichiometry (n), Heat of Reaction (ΔH) and Entropy of Reaction (ΔS).
- Small Molecule-Protein Interaction Thermodynamics
Instrument Info: VP-ITC (Microcal, Installed Jan. 2001)
Bring ~2mL of the titrand and titrand buffer per run as well as 2mL of the titrant. A suggested beginning concentration for a protein titrand is 0.05mM and about 0.2mM (4x) for the titrant molecule.
Training: Training involves the completion of one experiment under the supervision of Core Facility personnel. The experiment can be one of the trainee’s choosing.
To get a basic feel for the procedure of the experiment, it is recommended that you review the tutorial before coming in to use the instrument.