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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial",sans-serif;color:blue'>John, in my view the advantages of the Stafford meniscus-matching design (available from Spin Analytical) over the synthetic boundary centerpieces are that the long capillary design inhibits diffusion between the two channels and any inadvertent fluid transfer during loading and handling. The drawback of that long channel though is that it is harder to get the transfer needed to match the heights (it takes more force)---I find I may need to go to 10-12 K rpm. For some of the virus samples we run that is >= to the run speed, so you have to do it very quickly to avoid significant sedimentation during the meniscus matching spin.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial",sans-serif;color:blue'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial",sans-serif;color:blue'>John<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial",sans-serif;color:blue'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b>From:</b> RASMB [mailto:rasmb-bounces@list.rasmb.org] <b>On Behalf Of </b>John Sumida<br><b>Sent:</b> Thursday, December 18, 2014 9:45 AM<br><b>To:</b> rasmb@rasmb.org<br><b>Subject:</b> [RASMB] Centerpiece question<o:p></o:p></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Courier New"'>Dear RASMB,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Courier New"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Courier New"'>For interference measurements where matching the sample and reference channel menisci is essential, is there a preference for either the meniscus matching centerpiece versus synthetic boundary centerpiece. We would be interested to hear about pros and cons.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Courier New"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Courier New"'>Thank you and happy holidays.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Courier New"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Courier New"'>Best regards,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Courier New"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Courier New"'>John Sumida, Ph.D.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Courier New"'><a href="http://depts.washington.edu/cidb4bio/index.shtml"><span style='color:windowtext'>Analytical Biopharmacy Core Facility</span></a><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Courier New"'>University of Washington<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Courier New"'><a href="http://www.moles.washington.edu/"><span style='color:windowtext'>Molecular Engineering & Sciences Institute, G22</span></a><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Courier New"'>3946 West Stevens Way NE<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Courier New"'>Seattle WA 98195-1653<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='color:black'><o:p> </o:p></span></p></div></body></html>