• Binding constants.
• Reaction stoichiometry
• Thermodynamic Profile of the reaction which includes enthalpy (deltaH) and entropy (deltaS).
• Link to MicroCal for general information.

• Microcal.
• 1-800-633-3115

• January, 2001

• Volumes

  • The sample cell requires 2.5 ml of sample to be titrated.

  • Each addition of titrant must be at least 3 µl increments.

• Concentrations

  The following experiment was run with good results. These parameters should be considered the minimum concentrations used for this type of system.
  

• Link to Technical Tips at MicroCal: "Concentration for ITC experiments", "Registration for product literature", and other tips.
• Isothermal Titration Calorimetry of Protein-Protein Interactions, Pierce et al., 1999, Methods, 19:213-221. (pdf 108 kb)

• Primary Users (those who financially contributed to the purchase of the instrument) can sign up at any time.

• Secondary Users (those who did not contribute) can sign up only after noon on the Thursday preceding the week of use.

• Complete a Sample Submission Form if you want us to run your sample.

• The tutorial will take 1 day to complete.
• Download the Tutorial (Acrobat pdf 3.4 Mb).
• Please also review the above article by Pierce et al.
• Find more at the Protein Interaction Facility, University of Utah HSC.

PROBLEM.
Does your baseline badly drift?
Do you have DTT in your sample?

A user had 1mM DTT in the sample in the cell. The oxidation of the DTT as it reacted with O2 in the buffer was exothermic and was causing the baseline instability.

SOLUTION.

The facility has a tank of argon for the ITC. The user should purge the buffers with argon for a few minutes before degassing to remove all O2 from the buffer.

Further on this point, DTT is not the reducing agent of choice for ITC. β-mercaptoethanol is better at concentrations around 0.5 mM