Dear Artem, Thanks for your reply. You raise a number of points. Immediately, I should comment that the price of the PX Scanner is very considerably less than the $400k that you mention. Whilst - with the proteins and crystallisation conditions that you may be working with, visual inspection may be sufficient to differentiate salt from protein crystals (as you suggest), you will accept that generally this may not be the case. Thus, 'direct' inspection, using X-rays, must surely be the most appropriate way ? As you will be aware, the best looking crystals are seldom the best diffracting. This is well demonstrated through the PX Scanner 'Crystal Challenge', of course. Clearly, that's another prime purpose of the PX Scanner: to identify the 'best' crystals from amongst a multitude of candidates in a single droplet or across a plate, etc. Also, using the PX Scanner, we can check the effect of added cryo-protect. prior to freezing. Therefore, with this range of uses, the PX Scanner is clearly not intended for full 'data-collection' - but rather to most effectively support crystallisation optimisation and as a complement to in-house and central facility data-collection work. From the feedback that we receive, the PX Scanner is much valued by the number of groups which are now using these systems worldwide. However, even the proof of Grandma's apple pie is not until the eating. Accordingly, we most cordially invite you to visit one of our application labs - or perhaps one of our customer sites (by arrangement), with you, hopefully, being able to bring one or more of your crystallisation plates for inspection using the PX Scanner system. Since you are based in North America, I believe, one of my responsible colleagues will take up this invitation with you, off-BB. We look forward to our continuing discussions - with yourself, and all others who may be interested. Many Thanks and Best Regards, Marcus Winter (Agilent Technologies) [cid:[email protected]]<http://www.chem.agilent.com/en-US/Products/Instruments/X-raycrystallography/Pages/Crystalchallenge.aspx?cid=4710> From: Artem Evdokimov [mailto:[email protected]] Sent: 19 April 2011 02:50 To: WINTER,MARCUS (A-UnitedKingdom,ex1) Cc: [email protected] Subject: Re: [ccp4bb] viewing and scoring diffraction using the PX Scanner Hi, So what's your secret - how did you pack an entire synchrotron into a little box? OK, so I am being facetious a little. However, I cannot help asking myself why would I want to spend so much money on a system that is basically a (vertical) X-ray diffractometer in a box, with fixed distance, and sans the ability to collect data? I can only guess that the system costs in the range of $400K (am I right?) and for that money one could get a pretty nice actual X-ray diffraction set-up... Now, if this thing cost say ... $80K I may be interested, although most of our crystals are so small that this set-up will uniformly score them as 'no idea' because they don't even diffract at home on a 'real' X-ray source with a CCD. Artem P.S. the day I start routinely confusing protein and salt crystals is the day I stop working in the lab :) On Mon, Apr 18, 2011 at 3:00 AM, Marcus Winter <[email protected]<mailto:[email protected]>> wrote: Dear Chris, I'm prompted by your posting just to mention the Agilent Technologies PX Scanner 'Crystal Challenge' at: www.agilent.com/chem/crystalchallenge<http://www.agilent.com/chem/crystalchallenge> Thus, the only really useful assessment, or 'score', of objects (putative crystals) - or crystallisation conditions, is by the actual observed diffraction characteristics... and these preferably directly in situ, in the horizontal crystallisation plate, as achieved in the PX Scanner. Many Thanks and Best Regards, Marcus Winter (Agilent Technologies) [https://mail.google.com/mail/html/compose/static_files/blank_quirks.html?ui=2&ik=698a5dc8ca&view=att&th=12f67a0673d77925&attid=0.1&disp=emb&zw]<http://www.chem.agilent.com/en-US/Products/Instruments/X-raycrystallography/Pages/Crystalchallenge.aspx?cid=4710> From: CCP4 bulletin board [mailto:[email protected]<mailto:[email protected]>] On Behalf Of Chris Ulens Sent: 18 April 2011 08:24 To: [email protected]<mailto:[email protected]> Subject: [ccp4bb] viewing and scoring crystallization drops on the iPad Our laboratory has been developing an application to view and score crystallization drops on the iPad. We would like to know if crystallographers see potential benefits from the functionality of the iPad to swipe and pinch through drops. We are looking for specific comments from Formulatrix users, but other users are also welcome to comment. http://www.youtube.com/watch?v=LezurNhm0pA Specific ideas for future development are: - composition of crystallization buffers on a back-flip of the image drop - back-sync of crystallization scores on the iPad with the image database - emailing a drop image to colleague Thanks. -Chris --------------------------------------------------- Chris Ulens, Ph.D. Lab of Structural Neurobiology Department of Molecular Cell Biology Campus Gasthuisberg, ON1 Herestraat 49, PB 601 B-3000 Leuven Belgium http://www.xtal.be<http://www.xtal.be/>
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