Proprietary Commenting on Patrick’s message: (snip) might also consider that PEGs are notorious for impurities of various types; perhaps the Fluka reagent has less of an impurity that is particularly vexing for your specific protein. Of course, I suppose it might have more of a particular impurity that’s stimulating crystallization….
Quite a while ago, one of my colleagues had prepared a 50% PEG 4K solution using the highest grade that Fluka had to offer. To his surprise the next morning the plastic bottle that contained the solution was mostly empty. Closer inspection revealed that the “PEG” solution had eaten the plastic up, then spilled from the shelf where the reagent was stored to the bench below where it had dissolved additional plastic bottles, some which had spilled too. A lot like a famous scene of the “Alien” movie. When we inquired Fluka about this lot of PEG, their reply was that it was up to specifications, which were very lose, like the pH of a solution was between some rather extended pH range, the solution had no color, etc. but there were no actual characterization of the contents. Thierry Notice: This e-mail message, together with any attachments, contains information of Merck & Co., Inc. (2000 Galloping Hill Road, Kenilworth, New Jersey, USA 07033), and/or its affiliates Direct contact information for affiliates is available at http://www.merck.com/contact/contacts.html) that may be confidential, proprietary copyrighted and/or legally privileged. It is intended solely for the use of the individual or entity named on this message. If you are not the intended recipient, and have received this message in error, please notify us immediately by reply e-mail and then delete it from your system. ######################################################################## To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1 This message was issued to members of www.jiscmail.ac.uk/CCP4BB, a mailing list hosted by www.jiscmail.ac.uk, terms & conditions are available at https://www.jiscmail.ac.uk/policyandsecurity/
