Advances in high pressure bioscience and biotechnology ii, proceedings pages:481-484
2nd International Conference on High Pressure Bioscience and Biotechnology DORTMUND, GERMANY, SEP 16-19, 2002
The adiabatic compressibility of liquids can be determined by measurements of the sound velocity and the density, quantities that are related by the Newton-Laplace equation. In order to interpret the apparent compressibility of solutes in highly diluted solutions one must know the relation between the compressibility and the sound velocity of the solution under ideal conditions. The usual model is the Urick equation which assumes the validity of the Newton-Laplace equation for mixtures and the ideal additivity of the adiabatic compressibilities. However, there are a number of different models for the additivity of the sound velocity which are based on assumptions that are inconsistent with the Urick model. We revisit some approaches and discuss the consequences for the calculation of the compressibility of proteins.