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<DIV dir=ltr align=left><SPAN class=073242821-02062015><FONT color=#0000ff
size=2 face=Arial>Rob,</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=073242821-02062015><FONT color=#0000ff
size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=073242821-02062015><FONT color=#0000ff
size=2 face=Arial>Regarding the actual RI signal (as was already pointed out),
the RI detection system measures the difference in the speed of light between
the reference and sample chambers. Even if the RI laser will excite your
fluorophore (I'm pretty sure the wavelength is too long to excite fluorescein),
I can't see how there could possibly be enough fluoresence to compete
with the intensity of light going through the sample chamber from the laser
to cause any kind of corrupting fringe displacement.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=073242821-02062015></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=073242821-02062015><FONT color=#0000ff
size=2 face=Arial>The label certainly can affect the dn/dc of the
conjugated protein, but it is probably quite small (it's a weight average
calculation).</FONT> <FONT face=Arial><FONT color=#0000ff size=2>In this
case it seems the issue is whether or not the fluorphore affects your protein,
not the analytics.</FONT></FONT></SPAN></DIV>
<DIV><SPAN class=073242821-02062015><FONT color=#0000ff size=2
face=Arial></FONT></SPAN> </DIV>
<DIV><SPAN class=073242821-02062015><FONT color=#0000ff size=2
face=Arial>Regards,</FONT></SPAN></DIV>
<DIV><SPAN class=073242821-02062015><FONT color=#0000ff size=2
face=Arial></FONT></SPAN> </DIV>
<DIV><SPAN class=073242821-02062015><FONT color=#0000ff size=2
face=Arial>Karl</FONT></SPAN></DIV>
<DIV><SPAN class=073242821-02062015>
<P align=left><FONT size=2>******************************</FONT></P>
<P align=left><FONT size=2>N. Karl Maluf, Ph.D.</FONT><FONT size=2><BR>Senior
Research Scientist<BR>Alliance Protein Laboratories, Inc.<BR>6042 Cornerstone
Court West, Suite A<BR>San Diego, CA 92121 U.S.A<BR><BR>PH:
1-858-550-9401<BR>Fax: 1-858-550-9403 </FONT></P></SPAN></DIV></FONT></DIV><BR>
<DIV lang=en-us class=OutlookMessageHeader dir=ltr align=left>
<HR tabIndex=-1>
<FONT size=2 face=Tahoma><B>From:</B> RASMB
[mailto:rasmb-bounces@list.rasmb.org] <B>On Behalf Of </B>Robert
Shaffer<BR><B>Sent:</B> Tuesday, June 02, 2015 1:22 PM<BR><B>To:</B>
rasmb@list.rasmb.org<BR><B>Subject:</B> [RASMB] Fluorophore with Interference
Optics<BR></FONT><BR></DIV>
<DIV></DIV>
<DIV dir=ltr><SPAN style="FONT-SIZE: 12px">If I use a FITC-labeled ligand with
my protein, will the fluorophore cause any issue with the interference
optics</SPAN> for a sedimentation velocity run I plan to do next week? Or,
does fluorescein not affect the quality of interference data?
<DIV><BR></DIV>
<DIV>Thank you,</DIV>
<DIV>Rob<BR clear=all>
<DIV><BR></DIV>-- <BR>
<DIV class=gmail_signature>
<DIV dir=ltr>Robert Shaffer</DIV>
<DIV dir=ltr><A href="mailto:rshaff@bu.edu">rshaff@bu.edu</A><BR>MCBB, PhD
Program<BR>Boston University<BR>
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