Often you can also avoid this skin formation by adding a bit of your reservoir solution first to make it a larger droplet. Then the microtools as mentioned earlier or just two loops Jürgen
...................... Jürgen Bosch Johns Hopkins Bloomberg School of Public Health Department of Biochemistry & Molecular Biology Johns Hopkins Malaria Research Institute 615 North Wolfe Street, W8708 Baltimore, MD 21205 Phone: +1-410-614-4742 Lab: +1-410-614-4894 Fax: +1-410-955-3655 http://web.mac.com/bosch_lab/ On Nov 25, 2010, at 6:45, Rick <mbp08...@sheffield.ac.uk> wrote: > Dear CCP4 > > I looped a v.thin rod emerging from a cluster of v.thin rods that grew in > 29%PEG1500 and 0.1M SPG buffer at pH7.5 (succinic acid, sodium dihydrogen > orthophospate and glycine). The loop i used had been washed more than 10 > times with deionised water (so assumed as 'clean'). The crystals had grown at > 17degreesC, and looped out probably just below room temperature (~20-23 > degreesC). When transferred to 5% glycerol cryo-buffer the crystal > disintegrated (maybe due to glycerol being an unfavourable addition to the > mother-liquor). When i looked back at the original cluster-containing drop, a > very tough shell had formed over the surface of the drop, from which chunks > could be dug out...the nearest analogy is maybe like when you blow-torch > sugar on top of creme brulee, and have to crack it with your spoon. The > crystals within had also disintegrated. Any clues to what might have caused > this very tough shell to form, and maybe how to deal with it? > > Much appreciated > > Rick Salmon
