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Hi Madhavi

In conjunction with a 96-syringe hydra for filling reservoirs, we have been using two Genomic Solutions 8-tip "Cartesian" systems (Called HoneybeeX8 now I believe) for the past 6 years and have been generally very happy with them. They require a bit of looking after in terms of cleaning, degassing and general maintenance (like most sensitive machines: have a responsible person), but have set up about 30000 plates by now with 100nl + 100nl drops. We use it routinely for optimisation experiments and additive/detergent screens as well as initial screening. Consumable costs are pretty low (a few valves, tips and wash pumps over the years, along with a supply of isopropanol and water). The Innovadyne system is apparently quite similar but I have no experience of this. 
A few points to bear in mind though:
1) Evaporation of drops with small drop sizes - 100nl drops take only a few minutes to dry out completely, so you should either use a close-fitting cover over the plate, some kind of humidity chamber (each of the wells will be different though), have very fast plate setup time or chill the plate (which may affect protein solubility). We use a close fitting cover since each plate of 96 takes 10 minutes.
2) Contact and non-contact dispensing. Non-contact dispensing seems to be more accurate in terms of drop positioning in the well: important for images from automated imaging systems, image analysis software, and for fishing crystals out to test.
Non-contact dispensing won't give you so many problems with low surface tension solutions such as detergents, and is compatible with hydrophobic plates (important for membrane proteins).    

I dont think there is a perfect robot out there - all the robots I have seen have both advantages and disadvantages so it just depends what you will be using them for, what disadvantages you are willing to put up with, and of course your budget.

Happy shopping!
Tom


**                          Tom Walter B.Sc. M.Res.                   **
** Oxford Protein Production Facility        Tel: +44 (0)1865 287747  **
** Wellcome Trust Centre for Human Genetics  Fax: +44 (0)1865 287547  **
** Roosevelt Drive                           [log in to unmask]   **
** Headington, Oxford OX3 7BN                http://www.oppf.ox.ac.uk **


---- Original message ----
>Date: Wed, 9 Jan 2008 09:56:34 -0500
>From: "Nalam, Madhavi" <[log in to unmask]>  
>Subject: [ccp4bb] crystallization robot  
>To: [log in to unmask]
>
>Hi,
>Sorry for the non-ccp4 related question.
>We are planning to buy a crystallization robot. We looked at the
>'Mosquito'. We felt it is good for setting 96 well plates (for screening
>the conditions). Though they say that we can use it for 24 well plates
>(hanging drop) it didn't seem to be ideal because all it does is set the
>drops and everything else has to be done manually. 
>Can anyone suggest us other crystallization robots out in the market
>that are good?
>Thanks in advance,
>Regards,
>Madhavi