I've used variations of the Malvern instrument at two positions now, and I have to say I've never had a problem with them.
Yes, I believe it was designed to be a non-biological instrument, but I have to say it does a good job of DLS and SLS on proteins from 7-200KDa (in my experience) in a cuvette, down to ~12ul of sample. The software is fairly bulletproof, and the protein tools that give you estimates of particle axial ratios etc have proved to be pretty accurate after higher-resolution structure determination (PX, EM, SAXS) instrument itself has very few moving parts and I have never known one suffer any sort of breakdown - most problems are down to sample or cuvette cleanliness. That being said, in-line SEC-DLS-SLS etc is a much more powerful technique, but is less straight-forward, has a larger footprint and as has been mentioned, less-inexpensive. David "in no way affiliated to Malvern instruments" Briggs 2008/7/8 Jacob Keller <[EMAIL PROTECTED]>: > Why not get an in-line, flow-cell LS detector for use with your > chromatography system? We once had a great system, set up with a good SEC > column, UV detection at three wavelengths on an akta, followed by SLS and > DLS, and refractive index detector. The data were beautiful, as the SEC made > the background very clean, and one could see easily the degree of > mono/polydispersity of the SEC peak(s). It was not, however, inexpensive. > > Jacob Keller > > ******************************************* > Jacob Pearson Keller > Northwestern University > Medical Scientist Training Program > Dallos Laboratory > F. Searle 1-240 > 2240 Campus Drive > Evanston IL 60208 > lab: 847.491.2438 > cel: 773.608.9185 > email: [EMAIL PROTECTED] > ******************************************* > > ----- Original Message ----- From: "Gregor Witte" > <[EMAIL PROTECTED]> > To: <[email protected]> > Sent: Tuesday, July 08, 2008 10:27 AM > Subject: [ccp4bb] AW: [ccp4bb] DLS options? > > > Hmmm... > we had a demo of the Malvern Zetasizer instrument here, and to be honest: It > did not convince us at all (it is obviously built for non-biological > particle analysis).... > > The Viscotek is also a plug&play device, every pc with a USB is suitable. > > ..in the end... Viscotek and Malvern are the same company now(!) > > I guess the price for a DLS instrument is more or less independent of the > company.... aren't they all approx. 30-35k euros for a single-cuvette > system? > > > Gregor > > > -----Ursprüngliche Nachricht----- > Von: CCP4 bulletin board [mailto:[EMAIL PROTECTED] Im Auftrag von Roger > Rowlett > Gesendet: Dienstag, 8. Juli 2008 17:09 > An: [email protected] > Betreff: Re: [ccp4bb] DLS options? > > I'll second the recommendation for the Malvern Zetasizer. They are > rock-simple and interface with a computer through USB which makes future > computer upgrades relatively simple. The are however, not cheap--oops, > inexpensive. > > Cheers, > > > -- > ------------------------------------------------------------------------ > Roger S. Rowlett > Professor > Colgate University Presidential Scholar > Department of Chemistry > Colgate University > 13 Oak Drive > Hamilton, NY 13346 > > tel: (315)-228-7245 > ofc: (315)-228-7395 > fax: (315)-228-7935 > email: [EMAIL PROTECTED] > > > Andreas Förster wrote: >> >> Hey Thomas, >> >> also consider Malvern instruments. Their Zetasizers are really sweet >> and work with volumes smaller than 15ul if you use the smallest cuvette. >> http://www.malvern.com/LabEng/products/zetasizer/zetasizer.htm >> >> The last DynaPro that I've used, half as old as the universe but >> equipped with a 12ul cuvette, gave me really nice results also. Key is, >> as you discovered, to keep the cuvette meticulously clean. I used >> Pierce's RBS 35 Detergent for cleaning. Make a 2-5% dilution in a 50-ml >> beaker, heat to 70C in the microwave with the cuvette inside, let sit >> for a while, rinse with water and EtOH, and dry. Only touch with gloves >> afterwards. >> >> The protein sample must be spun down before the experiment. Half an >> hour at 13k in an Eppendorf centrifuge is sufficient. Make sure to >> avoid bubbles when adding the sample to the cuvette. >> >> Ah, nice data! >> >> Hope that helps. >> >> >> Andreas >> >> >> Thomas Edwards wrote: >> >>> Dear BB, >>> >>> >>> >>> Sorry for the off topic question: >>> >>> >>> >>> I would like to buy a Dynamic Light Scattering system. >>> >>> Could people suggest which they like the best and/or which is best value? >>> >>> >>> >>> I have in the past used a Protein Solutions Dyna Pro with micro cuvette >>> (I would like a micro cuvette option). However, it was very sensitive to >>> dust and bubbles, and the cuvette collects dust. >>> >>> I've never tried the one from Precision Detectors. >>> >>> Any other options? >>> >>> >>> >>> Thanks >>> >>> Ed >>> >>> >>> >>> ______________ >>> T.Edwards Ph.D. >>> Garstang 8.53d >>> Astbury Centre for Structural Molecular Biology >>> University of Leeds, Leeds, LS2 9JT >>> Telephone: 0113 343 3031 >>> > <http://www.bmb.leeds.ac.uk/staff/tae/>http://www.bmb.leeds.ac.uk/staff/tae/ >>> >>> <http://www.bmb.leeds.ac.uk/staff/tae/Research> >>> "The doubter is a true man of science; he doubts only himself and his >>> interpretations, but he believes in science". ~Claude Bernard >>> >>> >>> >>> > -- ============================ David C. Briggs PhD Father & Crystallographer http://www.dbriggs.talktalk.net AIM ID: dbassophile ============================
