Beyond the Poisson-Boltzmann model: modeling biomolecule-water and water-water interactions

Phys Rev Lett. 2009 Feb 27;102(8):087801. doi: 10.1103/PhysRevLett.102.087801. Epub 2009 Feb 24.


We present an extension to the Poisson-Boltzmann model in which the solvent is modeled as an assembly of self-orienting dipoles of variable densities. Interactions between these dipoles are included implicitly using a Yukawa potential field. This model leads to a set of equations whose solutions give the dipole densities; we use the latter to study the organization of water around biomolecules. The computed water density profiles resemble those derived from molecular dynamics simulations. We also derive an excess free energy that discriminates correct from incorrect conformations of proteins.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Models, Chemical*
  • Poisson Distribution
  • Proteins / chemistry*
  • Static Electricity
  • Water / chemistry*


  • Proteins
  • Water