Sorption calorimetry

The method of sorption calorimetry is designed for studies of hydration of complex organic and biological materials.

It has been applied for studies of surfactants,[1][2] lipids, DNA, nanomaterials[3] and other substances.

[4] Water evaporates, diffuses through the tube connecting two chambers of the calorimetric cell and is absorbed by the studied substance.

The amount of evaporated water is calculated from the thermal power registered in the vaporisation chamber: From the same data, the activity of water in the sample can also be calculated: From the thermal powers registered in the two chambers one can calculate the partial molar enthalpy of mixing of water.

During the sorption experiment the water content in the sample increases until it reaches a value high enough to make the process of diffusion of water vapor between the chambers very slow.