Differential Scanning Calorimeter

DSC background

Differential scanning calorimetry (DSC) is used to obtain thermodynamic parameters associated with heat-induced macromolecular transitions. The apparent molar heat capacity of a macromolecule is measured as a function of temperature, subsequently yielding:

1.      the absolute partial heat capacity of a molecule

2.      thermodynamic parameters, including change in enthalpy (ΔH), entropy (ΔS), and heat capacity (ΔC_p) of the transition

3.      the distribution and thermodynamic parameters of intermediate states.

DSC is typically applied to examine stability and domain structure of proteins and nucleic acids, temperature-induced transitions of lipids/membrane systems, and half-life of low molecular weight compounds. For example, proteins may be characterized in the context of mutagenesis, providing information on effects of a specific mutation on protein stability, folding intermediates, and oligomerization.

Microcal VP-DSC calorimeter

The VP-DSC instrument is highly sensitive, allowing for analysis of dilute macromolecular solutions. For example, lysozyme can be analyzed at micromolar concentrations in a 0.5 mL volume. The accessible temperature range is -10^oC to 130^oC.

The MicroCal VP-DSC is also equipped with a pressure accessory, expanding the instrument’s capabilities into a new area of investigation – pressure perturbation calorimetry. By recording changes in heat as a function of changing pressure above the solution, information on macromolecular solvation, accessible surface area, and solvent structure can be obtained.

Vendor

MicroCal