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 <[log in to unmask]>:
> 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: [log in to unmask]
> *******************************************
>
> ----- Original Message ----- From: "Gregor Witte"
> <[log in to unmask]>
> To: <[log in to unmask]>
> 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:[log in to unmask]] Im Auftrag von Roger
> Rowlett
> Gesendet: Dienstag, 8. Juli 2008 17:09
> An: [log in to unmask]
> 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: [log in to unmask]
>
>
> 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
============================
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