title: Spatial Decomposition Analysis of the Thermodynamics of Cyclodextrin Complexation.
abstract: We propose a method of spatial decomposition analysis (SDA) to study the thermodynamics of association in solution, based on three-dimensional molecular theory of solvation. We decompose the solvation thermodynamics quantities into the excluded volume and solvation shell terms and further break them down into partial contributions of the functional groups of the associating species. For illustration, we applied the SDA method to the complexation of β-cyclodextrin and 1-adamantanecarboxylic acid in water. We calculated the changes in the free energy and in the partial molar volume upon the association and decomposed them into the partial contributions of the functional groups to the excluded volume and solvation shell terms. The SDA shows that the adamantyl group of 1-adamantanecarboxylic acid is responsible for the complexation more than its carboxyl group and that the carboxyl has little contribution to the association process. The SDA results are in good agreement with the observation made in a recent molecular dynamics simulation. The SDA method can reveal a microscopic picture for association processes in solution in a number of areas, including protein stability, and might be a useful tool for rational drug design.
authors.affiliation: National Institute for Nanotechnology, 11421 Saskatchewan Drive, Edmonton, Alberta, T6G 2M9, Canada, and Department of Mechanical Engineering, University of Alberta, Edmonton, Canada.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Yamazaki
authors.affiliation: National Institute for Nanotechnology, 11421 Saskatchewan Drive, Edmonton, Alberta, T6G 2M9, Canada, and Department of Mechanical Engineering, University of Alberta, Edmonton, Canada.
authors.forename: Andriy
authors.initials: A
authors.lastname: Kovalenko