From: Stephen Harding <Steve.Harding@nottingham.ac.uk>
  To  : Borries Demeler <demeler@bioc09.v19.uthscsa.edu>
  Date: Sat, 2 Oct 1999 10:04:34 +0100

Re: "fringe" extinction coefficient

I should add..  
For a 12mm path length cell a good rule
is 
c (g/ml) = (J x wavelength(cm))/(1.2 x (dn/dc))

with dn/dc in ml/g.

If the protein is glycosylated the dn/dc will be lower than Jim Cole 
suggested, bottoming out to about 0.15 - 0.16.  Depends on the 
solvent as well!
Steve 

On 1 Oct 99, at 14:34, Borries Demeler wrote:

> Quick question:
> 
> What is the interference equivalent to an extinction coefficient under
> absorbance optics, ie. how much of a fringe shift can I expect for a
> given concentration of protein? How much variation is there for different
> proteins? If it is constant, is there a published number and what is it?
> 
> TIA, -Borries