Theoretical studies of the translational diffusion coefficient of charged macromolecules applied to bovine serum albumin

Our results suggest that there is an ’’intimate relationship’’ between the Doherty–Benedek–Stephen and Phillies theory for the diffusion coefficient of charged macromolecules. By introducing the hard sphere approximation for the radial distribution function between the macromolecules into the Phillies theory, we obtain a good approximation to the Doherty–Benedek–Stephen result. In order to take into account correlations in the positions of the proteins, we have also introduced the more realistic dilute gas approximation for the radial density function into the Phillies theory. Significantly better agreement with the experimental data has been obtained.