Analysis Interactions of Metals Ions and Proteins by Isothermal Titration Calorimetry (ITC) (CAT#: STEM-MB-2493-LGZ)

Introduction

The thermodynamics of metal ion binding to proteins and other biomolecules can be measured using isothermal titration calorimetry (ITC), which quantifies the binding enthalpy (ΔH°) and generates binding isotherms. Fitting of the isotherm provides the binding constant (K), allowing the free energy (ΔG°) and ultimately the binding entropy (ΔS°) to be determined. The temperature dependence of ΔH° can provide the change in heat capacity upon bonding (ΔC p°). However, measurements of metal binding by ITC can be affected by undesired reactions such as precipitation, hydrolysis, and redox, and often involve competing equilibria with buffers and protons, which contribute to experimental values (K ITC, ΔH ITC).