Dielectric Boundary Force in Biomolecular Solvation
Friday, October 23, 2015 - 2:30pm - 3:10pm
A dielectric boundary in a biomolecular system is a solute-solvent (e.g., protein-water) interface that defines the dielectric coefficient to be one value in the solute region and another in solvent. The inhomogeneous dielectric medium gives rise to an effective dielectric boundary force that is crucial to the biomolecular conformation and dynamics. This talk begins with a review of the Poisson-Boltzmann theory commonly used for electrostatic interactions in charged molecular systems and then focuses on the mathematical description of the dielectric boundary force. A precise definition and explicit formula of such force are presented. The motion of a cylindrical dielectric boundary driven by the competition between the surface tension, electrostatic interaction, and solvent viscous force is then studied. Implications of the mathematical findings to biomolecular conformational stabilities are finally discussed.