<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40"><head><meta http-equiv=Content-Type content="text/html; charset=iso-8859-1"><meta name=Generator content="Microsoft Word 14 (filtered medium)"><!--[if !mso]><style>v\:* {behavior:url(#default#VML);}
o\:* {behavior:url(#default#VML);}
w\:* {behavior:url(#default#VML);}
.shape {behavior:url(#default#VML);}
</style><![endif]--><style><!--
/* Font Definitions */
@font-face
{font-family:Helvetica;
panose-1:2 11 6 4 2 2 2 2 2 4;}
@font-face
{font-family:Helvetica;
panose-1:2 11 6 4 2 2 2 2 2 4;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
@font-face
{font-family:Tahoma;
panose-1:2 11 6 4 3 5 4 4 2 4;}
@font-face
{font-family:"Trebuchet MS";
panose-1:2 11 6 3 2 2 2 2 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman","serif";}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:purple;
text-decoration:underline;}
p
{mso-style-priority:99;
mso-margin-top-alt:auto;
margin-right:0in;
mso-margin-bottom-alt:auto;
margin-left:0in;
font-size:12.0pt;
font-family:"Times New Roman","serif";}
p.MsoAcetate, li.MsoAcetate, div.MsoAcetate
{mso-style-priority:99;
mso-style-link:"Balloon Text Char";
margin:0in;
margin-bottom:.0001pt;
font-size:8.0pt;
font-family:"Tahoma","sans-serif";}
span.apple-style-span
{mso-style-name:apple-style-span;}
span.EmailStyle19
{mso-style-type:personal-reply;
font-family:"Calibri","sans-serif";
color:black;}
span.BalloonTextChar
{mso-style-name:"Balloon Text Char";
mso-style-priority:99;
mso-style-link:"Balloon Text";
font-family:"Tahoma","sans-serif";}
.MsoChpDefault
{mso-style-type:export-only;
font-size:10.0pt;}
@page WordSection1
{size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;}
div.WordSection1
{page:WordSection1;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:black'>Good morning Richard,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:black'> Wyatt Technology offers the ViscoStar-II (</span><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'><a href="http://www.wyatt.com/solutions/hardware/viscostarii-viscometer.html">http://www.wyatt.com/solutions/hardware/viscostarii-viscometer.html</a>)</span> <span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:black'>, a commercially available online differential viscometer. If you have a SEC or GPC system, integrating the ViscoStar-II is straightforward and will provide the specific viscosity of your protein samples. With typical sample volumes for analytical SEC being under 100 ul, this small sample volume requirement is advantageous.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:black'> Coupling a concentration detector, such as our Optilab T-rEX (</span><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'><a href="http://www.wyatt.com/solutions/hardware/optilab-t-rex-refractive-index-detector.html">http://www.wyatt.com/solutions/hardware/optilab-t-rex-refractive-index-detector.html</a></span><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:black'>) will allow for calculations of the intrinsic viscosity as well. I’d be happy to discuss our ViscoStar-II or any of our detectors with you. Please let me know if you have any questions.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:black'>Best Regards,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:black'>Will<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:black'><o:p> </o:p></span></p><div><p class=MsoNormal style='margin-bottom:12.0pt'><b><span style='font-size:10.0pt;font-family:"Trebuchet MS","sans-serif";color:black'><img border=0 width=223 height=62 id="Picture_x0020_1" src="cid:image001.png@01CE6291.B67B7FD0" alt="Description: Wyatt logo for email from Geof"><o:p></o:p></span></b></p><p class=MsoNormal style='margin-bottom:12.0pt'><b><span style='font-size:10.0pt;font-family:"Trebuchet MS","sans-serif";color:black'>William Wittbold | Application Scientist | Northeast Customer Service Manager<br></span></b><span style='font-size:10.0pt;font-family:"Trebuchet MS","sans-serif";color:black'>Wyatt Technology Corporation<br>6300 Hollister Avenue | Santa Barbara, CA 93117-3253<br>Phone: (805)681-9009 x 214 | Fax: (805)681-0123<br>Web: <a href="http://www.wyatt.com/"><span style='color:black'>www.wyatt.com</span></a> | Skype: willwittbold<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:8.0pt;font-family:"Trebuchet MS","sans-serif";color:black'>Notice: This e-mail message, together with any attachments, contains information of Wyatt Technology that may be confidential, proprietary, copyrighted, privileged and/or protected work product, and is meant solely for the intended recipient. If you are not the intended recipient, and have received this message in error, please contact the sender immediately, permanently delete the original and any copies of this email and any attachments thereto.<o:p></o:p></span></p></div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:black'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> rasmb-bounces@list.rasmb.org [mailto:rasmb-bounces@list.rasmb.org] <b>On Behalf Of </b>Arthur Rowe<br><b>Sent:</b> Thursday, June 06, 2013 6:23 AM<br><b>To:</b> Richard Kingston<br><b>Cc:</b> rasmb@rasmb.org<br><b>Subject:</b> Re: [RASMB] Viscometer<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span style='color:#950F0B'>Hi Richard</span><o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='color:#950F0B'>If by 'protein solutions' you solutions of proteins which are 9more or less) 'globular', then you have a serious problem on your hands. The 'signal' with which you are dealing (difference in flow or roll time of a ball in a capillary or narrow tube) is very small, and is not readily measurable in solutions of low (<~5 mg/ml) concentration. You might want to consider reading through Steve Harding's 1997 review of this area - old, but the basic physical facts have not changed. As regards using commercially available equipment, our own experience in the NCMH is that even with the AMVn rolling ball viscometer, no longer marketed but as good as has ever been made, we struggle to cope with globular proteins. Even with careful pre-treatment of the lining of the tubes to minimise protein-surface interactions.</span><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='color:#950F0B'>A possible way forward is to follow the method published by Szuchet-Derechin and Johnson (1966) and add a small (few %) amount of glycerol to both solution and reference solvent. This increases the level of the 'signal', without - hopefully - any specific glycerol-induced effects. </span><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='color:#950F0B'>However, in the case of your own proposed work, there is a ray of hope. The <b>repeatability</b> of the (time) measurements for a given tube (or capillary) is normally much better than the <b>reproducibility </b>(experiment to experiment) of e.g. one concentration level to another. If it is the temperature dependence of the viscosity you are looking to asses, then by starting at a low temperature and working up (e.g. 5º at a time) you just might have enough precision, as you will be working in <i>relative</i> not <i>absolute</i> mode.</span><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='color:#950F0B'>Hope this is helpful. </span><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='color:#950F0B'>Regards to you, and all colleagues</span><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='color:#950F0B'>Arthur</span><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='color:#950F0B'>S.E.Harding (1997) Prog. Biophys. molec. Biol 68 207-262 (pdf available)</span><o:p></o:p></p></div><div><p class=MsoNormal><span style='color:#950F0B'>S. Szuchet-Derechin & P. Johnson (1966) Euro. Polymer J. 2 115-128</span><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='color:#950F0B'>Professor Arthur J Rowe<br>NCMH/Food Sciences<br>University of Nottingham<br>Sutton Bonington<br>Leics LE12 5RD UK<br><br>Tel: +44 115 9516156<br><a href="mailto:arthur.rowe@nottingham.ac.uk">arthur.rowe@nottingham.ac.uk</a></span><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>On 6 Jun 2013, at 05:14, Richard Kingston wrote:<o:p></o:p></p></div><p class=MsoNormal><br><br><o:p></o:p></p><div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Dear all,<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>I've become interested in measuring the viscosity of protein solutions at varying temperature, and wondered if anyone on the list could advise on the best way to do this using commercially available instrumentation. While there are many ways to measure viscosity, for protein applications minimizing the required sample volume is pretty critical. I note that Anton Paar sell an instrument that measures both dynamic viscosity and density (SVM 3000 Stabinger viscometer). If you skip the density measurement, the sample requirements look almost "manageable". Cambridge also sell a micro-sample viscometer (Viscolab 5000) which uses microlitre volumes. <o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>I'm having difficulty tracking down people that might have used these or similar instruments, and could comment on the practicalities for protein work. If anyone can offer advice, either on- or off-list, it would be appreciated.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Many thanks,<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Richard<o:p></o:p></p></div><div><p class=MsoNormal> <o:p></o:p></p></div><div><div><div><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Helvetica","sans-serif"'>Richard Kingston, PhD.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Helvetica","sans-serif"'>School of Biological Sciences<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Helvetica","sans-serif"'>The University of Auckland<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Helvetica","sans-serif"'>New Zealand<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Helvetica","sans-serif"'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Helvetica","sans-serif"'>website: <a href="http://persephone.sbs.auckland.ac.nz/richard/lab/">http://persephone.sbs.auckland.ac.nz/richard/lab/</a><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Helvetica","sans-serif"'><o:p> </o:p></span></p></div><p class=MsoNormal style='margin-bottom:12.0pt'><span style='font-size:9.0pt;font-family:"Helvetica","sans-serif"'><o:p> </o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p></div><p class=MsoNormal>_______________________________________________<br>RASMB mailing list<br><a href="mailto:RASMB@list.rasmb.org">RASMB@list.rasmb.org</a><br><a href="http://list.rasmb.org/listinfo.cgi/rasmb-rasmb.org">http://list.rasmb.org/listinfo.cgi/rasmb-rasmb.org</a><o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal><span style='font-size:13.5pt;font-family:"Helvetica","sans-serif";color:black'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-size:13.5pt;font-family:"Helvetica","sans-serif";color:black'><o:p> </o:p></span></p></div><p class=MsoNormal><o:p> </o:p></p></div><p class=MsoNormal><o:p> </o:p></p></div><p class=MsoNormal><o:p> </o:p></p><p>This message and any attachment are intended solely for the addressee and may contain confidential information. If you have received this message in error, please send it back to me, and immediately delete it. Please do not use, copy or disclose the information contained in this message or in any attachment. Any views or opinions expressed by the author of this email do not necessarily reflect the views of the University of Nottingham.<o:p></o:p></p><p>This message has been checked for viruses but the contents of an attachment may still contain software viruses which could damage your computer system, you are advised to perform your own checks. Email communications with the University of Nottingham may be monitored as permitted by UK legislation.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>