Do manufacturers change their crystallogenesis screens?

From: Chris Morris

Date: 24 August 2011 16:21


HI,

I've recently seen two examples where the description of a screen in a local database was different to the current one on the manufacturer's web site. This happened in two different labs, using different software, and with different screen manufacturers.

This could potentially lead to an optimisation screen that finds no hits, because the wrong condition is being optimised. Does anyone have experience of this? Am I just looking at a few one-off errors, or is there a general problem here?

The ideal solution is for screen manufacturers to give version numbers to their screens. Failing that, a good fix at the laboratory is to download the screen description every time a deep-well plate is received, and second best would be to download it every time a trial plate is set up. If there is a real concern here, we will implement one of these in xtalPiMS.

Regards,
Chris

____________________________________________
Chris Morris
http://pims.instruct-fp7.eu/
STFC, Daresbury Lab,  Daresbury,  Warrington,  UK,  WA4 4AD

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From: Jan Dohnalek
I have witnessed a change in the Hampton additive screen some years ago - on purpose - the formulation simply did not work OK. So I guess there are changes occasionally.

Jan



--
Jan Dohnalek, Ph.D
Institute of Macromolecular Chemistry
Academy of Sciences of the Czech Republic
Heyrovskeho nam. 2
16206 Praha 6
Czech Republic


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From: Flip Hoedemaeker
Hi Chris,

Yes, I have seen quite a few inconsistencies in screen formulations. Errors in listed conditions include recipe changes, but also typos both in the vendor description and in the database entries. At the moment I'm building a list of all discrepancies of the screens in the Formulatrix database together with the date found. This is a tedious work in progress but I'm happy to share the list sofar with people interested (offline). It will be published on the web site when complete. In the meantime, it is wise to double-check each hit condition found on the vendor web site, and in the cases where the exact composition is not published ask the vendor directly.

Flip

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From: Prince, D Bryan
Dear Flip,

I think with respect to the Formulatrix database, it would be useful to
have the date of entry into the database for each screen input. I agree
that there are discrepancies in the database, but they can generally be
traced to a change from one catalog to the next. If you have the date of
entry, then you can find the "correct" catalog to look at for your
formulation information. It would be useful if the various
crystallography suppliers would place their plate information in some
format easy to incorporate into the Rock Maker database. Maybe this is
something that can be discussed at the RAMC in France this fall.

Kind regards,
Bryan Prince