在STEM-HAADF和TEM明亮场模式之间进行全面的比较,用于成像树脂嵌入生物样本
Kayla Lynne Haberman1, Jelena Danilovic Lukovic2, Snezana Kovacevic2
1Department of Biology, Baylor University, One Bear Place #97388, Waco 76798-7388, TX, USA.
概括
扫描传输电子显微镜 (STEM) 具有高角度环状暗场 (HAADF) 探测器,与传统的明亮场传输电子显微镜 (TEM) 相比,为生物样品提供更优质的图像质量. 这种先进的技术增强了对比度和信号噪声比,使得许多样品不需要染色后.
科学领域:
- 电子显微镜的电子显微镜
- 生物成像成像技术
- 材料科学是一种材料科学.
背景情况:
- 发射电子显微镜 (TEM) 在明亮场模式是树脂嵌入生物样本的标准.
- 现代TEM提供扫描TEM (STEM) 模式,具有高角度环状暗场 (HAADF) 检测.
研究的目的:
- 为了比较TEM明亮场和STEM-HAADF模式之间的图像质量,用于各种生物样本.
- 评估在不同成像模式下对生物样品进行后对比的必要性.
主要方法:
- 嵌入树脂的生物样本 (酵母,藻类,植物叶,人体细胞,动物组织) 使用TEM明亮场和STEM-HAADF模式进行成像.
- 图像质量是根据对比度,亮度和信号与噪声比率进行评估的.
- 对比包括带有和没有对比后的样本 (乌兰酸,酸).
主要成果:
- 与TEM明亮场相比,STEM-HAADF模式通常产生更好的图像质量 (对比度,亮度,信号与噪声比率).
- 没有对比后的样本在STEM-HAADF模式下显著减少了粒度.
- STEM-HAADF模式为未染色的藻类,MCF7和肝细胞提供了更好的图像质量,在TEM模式中没有看到文物.
结论:
- STEM-HAADF模式对嵌入树脂的生物样本进行成像具有显著优势,特别是那些内在对比度低或未染色的截面的生物样本.
- 在使用STEM-HAADF时,对某些生物样本进行后对比可能是不必要的,简化了样本准备.
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