The Malvern PANalytical PEAQ-ITC is a highly sensitive isothermal titration calorimeter (ITC) used to study biomolecular interactions in a label-free, solution-based format. It is considered a "gold standard" for measuring binding affinity, stoichiometry, and the thermodynamics of binding events in a single experiment.  

Types of Samples and Applications:

The PEAQ-ITC can analyze a broad array of biomolecules and other compounds, including:

• Proteins and antibodies: To measure protein-protein or antibody-antigen interactions.

• Small molecules and ligands: For analyzing binding with proteins and other targets, a critical application in drug discovery.

• Nucleic acids: Such as DNA and RNA, for studying interactions with proteins or other nucleic acids.

• Lipids and carbohydrates: For characterizing their interactions with biomolecules.

• Enzyme kinetics: The instrument can be used to investigate the kinetics of enzyme-substrate reactions. 

The capabilities of the PEAQ-ITC allow for comprehensive analysis of molecular binding: 

• Thermodynamic analysis: It measures the heat released or absorbed when two molecules bind, from which it can calculate a complete thermodynamic profile of the interaction. The parameters determined include:

  • 1. Binding affinity (KD): The strength of the interaction. The PEAQ-ITC can measure affinities ranging from millimolar to sub-nanomolar.

    2. Stoichiometry (n): The molar ratio of the interacting molecules.

    3. Enthalpy (∆H): The heat absorbed or released during the binding process.

    4. Entropy (∆S): The change in disorder of the system during binding.

• Low sample consumption: The PEAQ-ITC requires only small amounts of sample (as little as 10µg) due to its sensitive, low-volume cell design.

• Label-free and in-solution measurements: The technique does not require the interacting molecules to be chemically modified or immobilized, so binding is measured in its native state.

• Wide affinity range: The system can detect a wide range of binding affinities and can measure very high-affinity interactions (picomolar) using competitive binding techniques.

• User-friendly operation: The accompanying software includes guided workflows, simulation tools, and automated data quality assessment to simplify the process for users of all experience levels.

• Chemically resistant materials: The sample cell is made of Hastelloy, a nickel alloy that is chemically resistant and compatible with biological samples.