脱水作为软X射线断层扫描的替代样品制备方法
Anthoula Chatzimpinou1, Charlotta Funaya2, David Rogers3
1Centre for Organismal Studies (COS), Heidelberg University, Heidelberg, Germany.
Journal of microscopy
|July 11, 2023
概括
软X射线断层扫描 (SXT) 可以通过临界点干燥 (CPD) 在不结的情况下成像细胞. 用CPD准备的细胞提供了与冷保存样品相比较的超结构细节,使SXT在没有冷设备的情况下可访问.
科学领域:
- 细胞生物学 细胞生物学
- 显微镜的使用方法
- 生物物理学的生物物理.
背景情况:
- 软X射线断层扫描 (SXT) 能够在近原生状态下对整个细胞进行高分辨率成像.
- 目前的SXT协议需要冷保存,由于特殊设备需求,限制了可访问性.
- 寻求替代样品制备方法以扩大SXT的适用性.
研究的目的:
- 在脱水细胞样本上研究SXT成像的可行性.
- 为了比较不同的脱水技术用于超结构性保存和收缩.
- 建立关键点干燥 (CPD) 作为一个可行的SXT样品准备方法.
主要方法:
- 在小鼠胚胎纤维细胞上对各种脱水过程 (包括临界点干燥和空气干燥) 的比较.
- 评估脱水后的超结构性保存和细胞收缩.
- 冷保存,空气干燥和CPD干燥细胞的软X射线断层成像.
- 对脱水细胞的X射线吸收和3D解剖细分的分析.
主要成果:
- 与空气干燥相比,临界点干燥 (CPD) 证明了优越的超结构性保存.
- 经过CPD干燥的细胞表现出高的结构完整性,最小的收缩.
- 虽然CPD干细胞显示有机细胞的X射线吸收增加 (3-7x),但差异吸收保持不变.
- 通过CPD干燥细胞的3D解剖学可以成功地被细分和分析.
结论:
- 脱水,特别是临界点干燥 (CPD),是一种可行的替代样本准备方法,用于软X射线断层扫描 (SXT).
- CPD允许使用SXT对细胞进行超结构可视化,而不需要冷保存.
- 这种方法将SXT成像的可访问性扩展到缺乏冷基础设施的实验室.
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