One thing I found with 2,3-Butanediol was for some crystallizations you can make it up a cryo solution with it at 12% and then put a thin layer it on top of the crystal droplet in a sitting drop well. Then you can loop the crystal and pull it up through the cryo layer - then out and to N2(l). Just how brief this is depends on your dexterity and also how well the crystal is engaged in the loop. My crystals were not very happy about the cryo but I could make it brief enough to get them out intact.
Good luck, Martyn Martyn Symmons MBU Cambridge ----- Original Message ---- From: Sean Seaver <[email protected]> To: [email protected] Sent: Wednesday, 24 March, 2010 18:47:38 Subject: Re: [ccp4bb] 2,3-butanediol Dear all, I would like to know which is the more suitable method of using 2,3-Butanediol as cryoprotectant? Addition in to reservoir buffer or crystal soaking or both can be tried? Cheers Gauri ------ I am sure both could be tried, but have found quite few papers mentioning brief soaking with 2,3-butanediol: Purification, crystallization and X-ray diffraction analysis of the extracellular part of the human Fc receptor for IgA, Fc[alpha]RI (CD89) http://scripts.iucr.org/cgi-bin/paper?cnor=bw5002 5-10 seconds Purification, crystallization and X-ray analysis of Hibiscus chlorotic ringspot virus http://scripts.iucr.org/cgi-bin/paper?cnor=gr2202 described as 'briefly' Crystallization and preliminary X-ray analysis of recombinant human acid [beta]-glucocerebrosidase, a treatment for Gaucher's disease http://scripts.iucr.org/cgi-bin/paper?cnor=pu0086 described as 'briefly' Crystallization and preliminary X-ray crystallographic studies of recombinant human betaine-homocysteine S-methyltransferase http://scripts.iucr.org/cgi-bin/paper?cnor=gr2115 'quickly transferred' Purification, crystallization and X-ray analysis of Hibiscus chlorotic ringspot virus http://scripts.iucr.org/cgi-bin/paper?cnor=pu0115 5% increments from 5 to 30% for 3 min at each step Hope that helps, Sean
