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<DIV><FONT face=Arial size=2>Dear Mark Agacan and
collegagues,</FONT></DIV>
<DIV><FONT face=Arial size=2>as over years dealing with
Membrane Proteins and detergents it is valid to match the
buffer with sucrose to achieve the right molecular weight
via Sed-equilibrium. In case of Sed-velocity
is the situation more complicated du to the density
distribution along tre radial distributionin the cell.(A. Lustig et
al BBA 1464 2000199 206) or (A.Ruf et al BBRCBioch. and </FONT></DIV>
<DIV><FONT face=Arial size=2>Biophy communication 315 247-254 Jan
2004)</FONT></DIV>
<DIV><FONT face=Arial size=2>Yours...ariel</FONT></DIV>
<DIV><FONT face=Arial size=2><A
href="mailto:ariel.lustig@bluewin.ch">ariel.lustig@bluewin.ch</A></FONT></DIV></BODY></HTML>