Got ice rings and want to get rid of them?

While the crystal is in the beam, carefully try the following.

Try annealing the crystal by blocking the stream for a few seconds, allowing the crystal to thaw, then unblock the stream to cool the crystal again. (Reference: New techniques in macromolecular cryocrystallography: macromolecular crystal annealing and cryogenic helium, B. Leif Hansona, Constance A. Schallb and Gerard J. Bunick, Journal of Structural Biology
Volume 142, Issue 1, April 2003, Pages 77-87)

Try washing the crystal with liquid nitrogen. Using a pipette, carefully aspirate liquid nitrogen into the pipette, then dispense several drops or even a gentle stream over the crystal and mount. A liquid nitrogen wash can also be used to remove creeping ice from caps, pins and loops.

有冰环并想摆脱它们？

当晶体在光束中时，请仔细尝试以下操作。

尝试通过阻塞流几秒钟来使晶体退火，让晶体解冻，然后解除阻塞流以再次冷却晶体。 （参考：高分子低温晶体学新技术：高分子晶体退火和低温氦，B. Leif Hansona，Constance A. Schallb 和 Gerard J. Bunick，Journal of Structural Biology
第 142 卷，第 1 期，2003 年 4 月，第 77-87 页）

尝试用液氮清洗晶体。 使用移液器小心地将液氮吸入移液器中，然后在晶体上滴几滴甚至是轻柔的液流并安装。 液氮清洗也可用于去除盖子、销钉和环上的爬行冰。

(Be aware of the potential for) detergent concentration mismatch between your mother liquor and the cryosolution. This particularly happens with vapor diffusion setups: there is a delicate balance of “free” detergent in the mother liquor versus the proportion of the detergent which is bound to the protein. Dropping a xtal into the cryosolution shocks the crystal with a bolus of extra free detergent. Hence, and counterintuitively, you may need to reduce the detergent concentration in the cryosolution to keep everything in balance. Try titrating down from 1% to even as low as 0.4% in the cryosolution. Under the conditions you are using the CMC of bOG is suppressed below the usual 0.67% (w/v).

Also, the behavior of many of the alkyl glycoside detergents is very temperature sensitive. So be careful about the temperature of all the solutions you use.

R. Michael Garavito, Ph.D.
Submitted to CCP4 bulletin board February 2007
Edited by Hampton Research Corp.

（请注意）母液和冷冻溶液之间的洗涤剂浓度不匹配的可能性。 这尤其发生在蒸汽扩散装置中：母液中的“游离”去污剂与与蛋白质结合的去污剂比例之间存在微妙的平衡。 将 xtal 滴入冷冻溶液中会用一团额外的游离洗涤剂冲击晶体。 因此，与直觉相反，您可能需要降低冷冻溶液中的洗涤剂浓度以保持一切平衡。 尝试在冷冻溶液中从 1% 滴定到甚至低至 0.4%。 在您使用的条件下，bOG 的 CMC 被抑制在通常的 0.67% (w/v) 以下。

此外，许多烷基糖苷去污剂的行为对温度非常敏感。 因此，请注意您使用的所有溶液的温度。