Re: [ccp4bb]: Dynamic Light Scattering

[Yu Wai Chen <ywc@mrc-lmb.cam.ac.uk>]

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> In our lab we have a Dynapro system (from Protein Solutions) for dynamic
> light scattering analysis.

We use a DynaPro-801 with MSTC here, controlled by the Protein Solutions
software, Dynamics v3.3.

> We are not having good results either for
> single proteins or complexes analysis. Even using the filters
> recommended by the manufacturer to prepare samples, the background
> signal is always very high.

May I suggest you first check if the machine is working properly?  You
can check photon counts of pure water and check it against your machine
document to see if this is correct.  Then you can use the BSA standard
(purchase from PIERCE) and see if you can get good results.

> Has anyone experience (problems) with this system and technique?. We
> have collected some opinions about it, and the software appears to be an
> important point to obtain good results.

We have used DLS to characterize a number of proteins and it is in
general a reliable technique.  If possible, filter the sample through
0.02 micron acrodisc.  I found this helps a lot.

Wai
-- 
===================================================================
Yu Wai CHEN, Ph.D. ..................   email:ywc@mrc-lmb.cam.ac.uk
 Centre for Protein Engineering,             tel:+44-(0)1223-402148
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