Isothermal Titration Calorimetry (ITC)
Isothermal titration calorimetry (ITC) is a gold standard biophysical method for determining the thermodynamic parameters of molecular interactions in solution. This label-free technique directly measures the heat released or absorbed during a biomolecular binding event. It is commonly used to determine the binding of small molecules such as medical compounds to large macromolecules such as proteins.
In a signaling pathway, there are several components such as ligand, receptor, primary effector, second massager, secondary effecter and so on. It is crucial to determine the binding of a ligand and its receptors. For example, it is of great interest to discover which protein is an amino acid sensor in the mTORC1 signaling pathway.
With advanced technologies, CD BioSciences offers highly sensitive and flexible Isothermal Titration Calorimetry (ITC) services to make a complete thermodynamic profile of the biomolecular binding events in your interest.
General Principle of ITC
A reference cell and a sample cell in a temperature-controlled compartment.
Binding enthalpy(ΔH), binding affinity (Ka) and precise stoichiometry (n) can be determined through ITC. Free enthalpy of binding (ΔG) and binding entropy (ΔS) can be further calculated.
Advantages of ITC
- Wide Molecule Size
- Low Sample Consumption
- High Sensitivity
- Spectroscopic Properties Irrelevant
- Complete Thermodynamic Profiling
Either binding partners require no chemical modification, avoiding any influences of labels.
The measurements happen in solution. No immobilization of either binding partner is required.
ITC measures the affinity of binding partners in their native states.
The molecular weight of reactants is not limited from small molecules to MDa.
Sample quantity can be as low as 300 µl with a concentration of 20 µM.
The binding constant can be as low as nM.
The measurement is unaffected by the spectroscopic properties of reactants.
ITC is the only technique that can simultaneously determine all binding parameters (binding affinity/ Ka, reaction stoichiometry/ n, enthalpy/ ∆H and entropy/ ΔS) in a single experiment.
What ITC Tells
Binding Enthalpy (ΔH)
Binding Entropy (ΔS)
Free Enthalpy of Binding (ΔG).
Binding Affinity (Ka)
Precise Stoichiometry n (e.g. 1:1 or 2:1 binding)
In your research of cellular signaling pathways, are you still struggling to find the best way to determine the thermodynamic parameters of your biomolecular interactions? ITC is a highly efficient method for this purpose, which has been widely used to characterize the binding affinity of ligands and their receptors.
It can be used to analyze interactions between proteins, peptides, DNA, RNA, aptamers, small molecules, molecular fragments, ions, lipids, virus-like-particles, and artificial particles, such as
- Protein-protein Interactions
- Protein-DNA Interactions
- Protein-RNA Interactions
- Protein-small Molecule Interactions
- DNA-small Molecule Interactions
- RNA-small Molecule Interactions
CD BioSciences offers cost-effect, high quality and hassle-free isothermal titration calorimetry (ITC) services to our clients worldwide. We guarantee to deliver our results on time. Please feel free to contact us.
For research use only. Not intended for any clinical use.