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Hello, My crystals in fact grew out of 20% peg4K and 20% isopropanol at 20 degrees and so were already effectively cryoprotected in the drop. Opening up the well at room temperature led to the crystals whirling around in the drop and made it hard to pick up a single crystal in the loop. The effect is not as bad at 4 degrees however and this has been other people's experience as well. By increasing the viscosity by adding peg to 30% instead of using higher concentrations of isopropanol as the cryoprotectant and moving the tray to 4 degrees, the solvent movement was slowed dramatically and I could work quickly through sequential transfers in 5% peg increments into my final cryoprotectant. Of course you need to check that there isn't a deleterious effect of moving your crystals to 4 degrees if they were not grown there. Hope this helps, Charu On 8/26/08 11:17 AM, "Narayanan Ramasubbu" <[log in to unmask]> wrote: > Dear All: > I have obtained good crystals from 20% isopropanol but this is my first > time dealing with this agent. > Help in handling the crystals, dealing with evaporation etc. is highly > appreciated. > Thank you > Subbu