<HTML dir=ltr><HEAD><TITLE>Re: [RASMB] determination of phage particle concentration</TITLE>
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<DIV dir=ltr><FONT face=Arial color=#000000 size=2>Dear Sabine</FONT></DIV>
<DIV dir=ltr><FONT face=Arial size=2>Simple turbidity measurements (making sure you are <U>away</U> from absorption maxima) using a good quality spectrophotometer <U>may </U>suffice for the sort of information you are after - particle concentration, although stricvtly speaking it is not a hydrodynamic method.. This is is the usual method for measuring concentrations (particles per ml) of very large assemblies such as spores and I think it works for smaller assemblies that are not too dilute..</FONT></DIV>
<DIV dir=ltr><FONT face=Arial size=2>Victor Bloomfield's group did quite a bit on the turbidity of phages in the late 70's and gave the relevant formulae (you may need the approx mol. wt value) - if you look up Bahls and Bloomfield (and not Victor's QLS papers) that should give you a lead!</FONT></DIV>
<DIV dir=ltr><FONT face=Arial size=2>All best</FONT></DIV>
<DIV dir=ltr><FONT face=Arial size=2>Steve Harding</FONT></DIV>
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<DIV dir=ltr><BR><FONT size=2>> Dear all,<BR>><BR>> we are trying to obtain the concentration of bacteriophages in a<BR>> solution, concentration meaning the number of particles per ml. The<BR>> solution is supposed to be monodisperse and the MW is (roughly) known<BR>> but could be determined exactly. Is the any idea of how to do this<BR>> with a hydrodynamic method (staining is difficult to compare between<BR>> phage mutants and counting infected cells is tedious). I`ve got the<BR>> "feeling" that one could use the number-averaged MW, but maybe this is<BR>> totally wrong.<BR>><BR>> Thank you for any hints, literature is also welcome.<BR>><BR>> Cheers,<BR>><BR>> Sabine<BR>><BR>><BR>><BR>><BR>> Sabine Kaltofen<BR>> PhD student<BR>><BR>> Universität Potsdam<BR>> Department of Physical Biochemistry<BR>> Institute of Biochemistry and Biology<BR>> Karl-Liebknecht-Str. 24-25, Haus 25, Raum B/0.05<BR>> D-14476 Potsdam-Golm<BR>> Telefon: +49-(331)-977-5245<BR>> Email: kaltofen@uni-potsdam.de<BR>><BR>></FONT></DIV><br/>
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