Protein Solutions
Calorimetry, Research and Consulting

Protein Solutions provides a range of scientific services such as assistance in experimental research, theory-based interpretation of data, as well as "know how" and consulting in protein/peptide stability and thermodynamics.

Upcoming Events

July 18, 2012

World Drug Target/Deliver Online Symposium Series

Past Events


Lecture presentation at GE Healthcare meeting on label-free technology in Copenhagen University, Denmark

Lecture presentation at TA Instruments workshop and seminar at Roskilde University, Denmark

Isothermal Titration Calorimetry (ITC)

ITC is a quick and simple method for measuring molecular interactions. Applications of this method are numerous and include investigation of binding between proteins, ligands, inhibitors, antibodies, nucleic acids, lipids and so on. ITC can also be used to study enzyme kinetics or protein folding.

Obviously, since all reactions are energetically driven, to evaluate their ”favorability” one should only measure the Gibbs free energy of interaction. This can be done by a variety of techniques and often optical changes of the system upon interaction are used for this purpose. However, only through the measurement of heat, one can obtain a direct access to the enthalpy of interaction and calorimetry is an only method that does just that. Therefore, due to its ability to distinguish between the enthalpic and entropic contributions, ITC can provide a unique assessment of driving forces, contributing to the overall Gibbs free energy of interaction.

Thermodynamic parameters obtained from a single ITC experiment include binding constant, K, enthalpy of interaction, ΔH, and the number of binding sites, n. These parameters can be used to calculate the Gibbs free energy, ΔG (using the formula ΔG=-RT·ln(K)), and the entropy, ΔS (through the equation ΔS=(ΔH-ΔG)/T). An animation below visualizes a typical ITC experiment.

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