From: Houphouet Hy Yarabe <hyarabe@unix1.sncc.lsu.edu>
  To  : rasmb@bbri.harvard.edu
  Date: Thu, 29 Apr 1999 23:21:22 -0500 (CDT)

Molecular weight (Mw)

I reported Mw by sedimentation equilibrium and S values determined by
sedimentation velocity as part of a paper I've submitted to Analytical
Chemistry. The paper got some good reviews.  However, one of the reviewers
wants me to consider adding values of diffusion coefficient (D) which can
be obtained from the width of sedimenting boundaries measured in the
sedimentation velocity.  With D values, he adds, Mw results can be
calculated using the Svedberg equation and compared with Mw obtained via
sedimentation equilibrium.  This comparison, he concludes, would provide
an excellent test of the accuracy of reported s and Mw (sedimentation
equilibrium) values.

I aggree with him on the principle.  However, in my mind, the diffusion
coefficients calculated from sedimentation velocity lack accuracy. Could
somebody give me some input to address this reviewer.

"Struggle to know more ....."

Yarabe

Louisiana State University
Baton Rouge, LA 70803
Tel: 225-388-3919
Fax:  225-388-3971