Hi all, Thanks for the reply. I have ultimately used 15% glycerol as cryo. It worked well. I referred to this paper McFerrin and Snell, Cryoprotectant quantification J. Appl. Cryst. (2002). 35, 538±545. Now setting up grid with different concentrations of jeffamine.
Arpita Below is a summary of messages I received; Hi.. Sorry for the non-ccp4 query.I have a protein crystal growing at 0.1 M HEPES-Na (pH7.5), 20% Jeffamine M-600 (sitting drop). Can anyone please suggest for the cryprotectant to be used? Arpita. Hi Arpita, do you work in the group of Shekhar Mande????? if yes then can you please convey my regards to him.....well anyways coming to your question, you can use Jeffamine itself as a good cryo protectant.. i had recently used 45 % jeffamine as an effective cryo..... but you should be careful that direct transfer to 45 % jeffamine "might" destroy the diffraction of the crystal.... what i will be tempted to do is slowly increasing the concentration of jeffamine.. you can try doing both by direct transfer or by equlibration......do let me know if you have any doubts... regards Avinash hi.. thank u 4 the reply...ya..i m working with him ...i will surely convey to him..what is equilibration?..... actually i do not have too many crystals in that condition. can I set up a grid upto 45% jeffamine? Arpita yes you can and i will recommend you to use online grid make "SAmBA".. if you cannot find the link then you can get it from my web-page (interactive tools... my web page link is http://www.freewebs.com/avikale/ please feel free to ask any question if you might have.... regards Avinash Arpita, Try this. Cryoprotectant database for protein crystals. http://idb.exst.jaxa.jp/db_data/protein/200304E02478000.html best Yogi Jeffamine itself is a cryo. Simply raise its concentration, Dima jeffamine itself might be a cryo. jan Since Jeffamine M-600 is a small polymer, I believe you can freeze your crystals directly. If required you may have to increase the Jeffamine conc'n to 25-30% (Let me know if it worked). Anthony I think you can use the crystals as they are or increase jeffamine to 30%. Never had jeffamine but I think it is like PEG400. Jacqueline
