Glossary

Isothermal Titration Calorimetry (ITC)

Q: Why is Isothermal Titration Calorimetry (ITC) important in peptide research?

Isothermal Titration Calorimetry (ITC) is a fundamental concept in analytical as it relates to peptide science. It directly influences experimental design, compound characterization, and the reliability of research outcomes across biochemistry and molecular biology disciplines.

Analytical

Isothermal Titration Calorimetry (ITC) — A biophysical technique that directly measures heat released or absorbed during molecular binding events, providing thermodynamic data for peptide-receptor interactions.

What Is Isothermal Titration Calorimetry?

Isothermal titration calorimetry (ITC) measures the heat released or absorbed during a biomolecular binding event. By titrating a peptide ligand into a receptor solution, ITC directly determines all thermodynamic binding parameters in a single experiment: dissociation constant (Kd), enthalpy change (ΔH), entropy change (ΔS), stoichiometry (n), and Gibbs free energy (ΔG).

Advantages

Label-free: No fluorophores, radioactivity, or surface immobilization required
Complete thermodynamics: Only method providing ΔH and TΔS directly, revealing whether binding is enthalpy-driven (hydrogen bonds, van der Waals) or entropy-driven (hydrophobic effect)
Solution phase: Both partners free in solution at physiological conditions

Limitation

Requires relatively large amounts of both peptide and target (micrograms to milligrams) compared to SPR. Low sensitivity for very tight binders (Kd < 1 nM) without competitive displacement protocols.

Frequently Asked Questions

What is Isothermal Titration Calorimetry (ITC)?

A biophysical technique that directly measures heat released or absorbed during molecular binding events, providing thermodynamic data for peptide-receptor interactions.

Why is Isothermal Titration Calorimetry (ITC) important in peptide research?