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Differential Scanning Calorimetry — A Method for Assessing the Thermal Stability and Conformation of Protein Antigen
Published on: March 4, 2017
Heat capacities of protein functional groups
G I Makhatadze1, M M Lopez, P L Privalov
1Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409, USA. qegim@ttacs.ttu.edu
Biophysical Chemistry
|February 28, 1997
Summary
This study determined partial molar heat capacities of molecular groups in aqueous solution using scanning calorimetry. The CH2 group
Area of Science:
- Physical Chemistry
- Solution Chemistry
Background:
- Understanding the thermodynamic properties of functional groups in aqueous solution is crucial for predicting molecular behavior.
- Partial molar heat capacities provide insights into solute-solvent interactions and molecular structure.
Purpose of the Study:
- To determine the partial molar heat capacities of CH2, CONH, COOH, and COONa groups in aqueous solution.
- To investigate the temperature dependence and structural influences on these heat capacities.
Main Methods:
- Precise scanning calorimetry was employed to measure heat capacities.
- Measurements were conducted on series of carboxylic acids, sodium salts, alcohols, and N-substituted amides.
- Data were analyzed to derive partial molar heat capacities of specific functional groups.
Main Results:
- The partial molar heat capacity of the CH2 group is temperature-independent and decreases linearly with increasing temperature.
- COOH and COONa groups exhibit negative partial molar heat capacities at room temperature, decreasing non-linearly with temperature.
- The partial molar heat capacity of the CONH group is dependent on the model compound, correlating with water-accessible surface area.
Conclusions:
- Functional groups display distinct thermodynamic behaviors in aqueous solution.
- Temperature and molecular structure significantly influence partial molar heat capacities.
- These findings contribute to a deeper understanding of solvation thermodynamics and molecular interactions.
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