Dear all, I am now optimizing a hit which contains about 30% 1,4-dioxane using hanging-drop vapor diffusion at 25 degree. I am having a hard time to reproduce the results: most of the times the drops are either dry in one day or full of precipitate, and only occasionally could I get small crystals. Is there a way to control the vapor diffusion process, like using oil to seal the reservoir? (I know paraffin is permeable to dioxane) Also if someone could refer me to studies on the effects of reservoir volume and surface area to the crystallization kinetics, that would be very helpful.
I am also seeking for recommendations for freezing crystals in this condition. What kind of cryoprotectant has a higher chance? Another problem is that when I tried to freeze the crystals, the drop dries super rapidly, and the crystals will dissolve if I add reservoir buffer. But I would assume good cryoprotectant could do the job. On the other hand, this points back to my previous question on "dioxane-impermeable" oil. If this magic oil exists, I could use it to seal the drop when freezing. Thank you for help! Sincerely, Chen
