凝固的有机液体在冷温度下的基本特性,用于电子显微镜可视化和分散系统的样品制备
1Institute for Extra-cutting-edge Science and Technology Avant-garde Research (X-star), Japan Agency for Marine-Earth Science and Technology (JAMSTEC), 2-15 Natsushima-cho, Yokosuka, Kanagawa 237-0061, Japan.
Microscopy (Oxford, England)
|January 9, 2025
概括
使用低温电子显微镜 (cryo-EM) 绘制有机液体 (OLs) 的图像具有挑战性. 这项研究评估了cryo-EM的OL特性,揭示了合适的OL对于非水性系统的无工件成像至关重要.
科学领域:
- 材料科学 材料科学 材料科学
- 生物物理学的生物物理.
- 电子显微镜电子显微镜
背景情况:
- 低温电子显微镜 (cryo-EM) 对于在液体中的成像结构至关重要.
- 使用cryo-EM对有机液体 (OLs) 的成像比水系统少,这是由于对固态OLs属性的理解不足.
- 从OL属性中可以产生人工物,阻碍准确的结构确定.
研究的目的:
- 调查OLs与其在冷EM中的适用性相关的物理性质.
- 确定各种OLs适合于非水系统的冷电磁成像.
- 为了确定稳定和无工件的冷电磁分析的关键OL特性.
主要方法:
- 对OLs的相变数据的总结.
- 测量了77K的固体密度和OLs的升华速度.
- 计算了升华特性和结晶性.
- 分析了OL-in-water乳液的聚焦离子束截面,以确定结器件.
主要成果:
- 升华温度,压力,速率和结晶性是冷EM适合性的关键因素.
- 计算的升华速度与实验测量值相对应得很好.
- 通过比较液体和固体密度来估计结晶度.
- 结OLs可以引入裂和空洞等工件,特别是在高收缩率下.
- 对于冷-EM,OLs的适用性在结构异构体之间有很大差异.
结论:
- 了解OL的特性,特别是升华和结晶性,对于成功的冷EM至关重要.
- 适当的OL选择对于成像非水系系统而不是文物至关重要.
- 对OL特性进行进一步的研究将有助于在各种领域推进冷EM应用.
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