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<DIV><FONT face=Arial size=2>Greetings,</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>I am currently doing some velocity sedimentation
experiments using absorbance optics on a 33 kDal protein and I am processing my
data with DC/DT plus.</FONT></DIV>
<DIV><FONT face=Arial size=2>I have several questions to ask to the g(S)
function specialist.</FONT></DIV>
<DIV><FONT face=Arial size=2>first I was spinning at 50.000 rpm and scanning 3
replicates with a radial increment of 0.02 this was resulting in a scan every
3:30 minutes (roughly).</FONT></DIV>
<DIV><FONT face=Arial size=2>my g(S) function is very nice clearly indicating a
single component system with a S of about 2.3 S.</FONT></DIV>
<DIV><FONT face=Arial size=2>As It seems that the more frequently you scan the
better it is, I therefore tried only 2 replicates and still a radial increment
of 0.02 and now it allows me to scan every 2 minutes (approximately).
nevertheless my function does not look as nice (this is the same sample). I also
increased the speed to 55.000 rpm.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>so is it a result of a lower number of replicates
(more noise)?. Is it best to scan more frequently with more
noise versus less frequently with more replicates?</FONT></DIV>
<DIV><FONT face=Arial size=2>Is there for sedimentation velocity a really
optimal speed (I know the reference curve) or the faster you spin the better it
is?</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>Thanks in advance for your answers.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>Pascal Egea</FONT></DIV>
<DIV><FONT face=Arial size=2>UCSF department of Biophysics and
Biochemistry</FONT></DIV></BODY></HTML>