<html><body><div style="color:#000; background-color:#fff; font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px"><div class="" style="">Hi all (especially
hoping Steve Harding is active),<o:p class="" style=""></o:p></div><div class="" style=""><o:p class="" style=""> </o:p></div><div class="" style="">I recently saw the
Malvern viscosizer. It is a capillary
viscometer and taylor dispersion instrument.
(Taylor dispersion looks at the diffusion pattern of a small plug of
sample in a capillary). Because of the
small volumes used, it could be useful for screening early limited supply
proteins for viscosity problems.<o:p class="" style=""></o:p></div><div class="" style=""><o:p class="" style=""> </o:p></div><div class="" style="">Are there any
general thoughts on the technology?<o:p class="" style=""></o:p></div><div class="" style="" id="yui_3_16_0_1_1433333972801_3436"><o:p class="" style=""> </o:p></div><div class="" style="" id="yui_3_16_0_1_1433333972801_3437">I remember Steve
Harding telling us at BITC that you never use rolling ball viscometers on
proteins: the proteins stick to the
ball.<o:p class="" style=""></o:p></div><div class="" style="" id="yui_3_16_0_1_1433333972801_3438">Recently we found
out here that the regular Anton Paar cone and plate rheometers sometimes need
PS-80 in protein samples or the air water interface around the outside edge can
predominate the viscosity measurements.<o:p class="" style=""></o:p></div><div class="" style="" id="yui_3_16_0_1_1433333972801_3439"><o:p class="" style=""> </o:p></div><div class="" style="" id="yui_3_16_0_1_1433333972801_3440">I did ask whether
most samples just stick to the capillary and disappear or run anomalously, but
the answer was they had a super coating so most things won’t stick. This coating makes the capillary impossible
to clean (so you buy more capillaries from Malvern). And that the taylor dispersion fitting will
tell you if and approximately how much the sample interacts with the capillary
walls.<o:p class="" style=""></o:p></div><div class="" style="" id="yui_3_16_0_1_1433333972801_3441"><o:p class="" style=""> </o:p></div><div class="" style="" id="yui_3_16_0_1_1433333972801_3442">Kind Regards,<o:p class="" style=""></o:p></div><div class="" style="" id="yui_3_16_0_1_1433333972801_3443"><o:p class="" style=""> </o:p></div><div id="yui_3_16_0_1_1433333972801_3394">
</div><div class="" dir="ltr" style="" id="yui_3_16_0_1_1433333972801_3457">David Hayes<o:p class="" style=""></o:p></div><div id="yui_3_16_0_1_1433333972801_3394" class="" style=""><br class="" style=""></div></div></body></html>