Shivesh
It's often very difficult to harvest crystals from conditions that contain isopropanol because the alcohol is volatile - especially with 50% or over! A solution that has worked several times it so use the Vapor Batch plates. http://www.douglas.co.uk/vb.htm You can cover the drops with oil, and then put isopropanol solution into the "moat" of the plate. The alcohol diffuses through the oil into the drops, while the oil acts as a buffer, reducing loss of alcohol during harvesting and freezing. For a case study see http://www.douglas.co.uk/winner1.htm Please let me know if anyone wants samples. Patrick -- [EMAIL PROTECTED] Douglas Instruments Ltd. DouglasHouse, EastGarston, Hungerford, Berkshire, RG177HD, UK Directors: Peter Baldock, Patrick Shaw Stewart, James Smith http://www.douglas.co.uk/ Tel: 44 (0) 148-864-9090 US toll-free 1-877-225-2034 Regd. England 2177994, VAT Reg. GB 480 7371 36 From: CCP4 bulletin board [mailto:[EMAIL PROTECTED] On Behalf Of shivesh kumar Sent: 05 March 2008 07:23 To: [email protected] Subject: [ccp4bb] isopropanol as a precipitant Dear all Sorry for non-CCP4 query. I have crystallized a 7kDa protein in 50-60% of isopropanol,pH 4.0-4.6.The interesting thing is that the xtal appears within 5 hrs at 16 degree. The protein conc is 5mg/ml and drop size is 3+1 with mother liquor 300 micro lt.Numerous xtals appears and but small is size.Do anyone can share their experience with Isopropanol as a precipitant and to improve the xtal quality with other precipitants.All suggestions are welcome. Thanx in advance. Shivesh
