Kado M, Richardson M, Rajyaguru J M, Muszynski M J, Friedman H, Yamamoto Y
Center for Research and Education in Optics and Lasers, University of Central Florida, Orlando, Florida 32826, USA.
Proc Soc Exp Biol Med. 1999 Jan;220(1):27-30. doi: 10.1046/j.1525-1373.1999.d01-4.x.
A compact, high-resolution, laser-plasma, x-ray contact microscopy method using a table-top Nd:glass laser system has been developed. This x-ray microscopy system was applied for the observation of macrophage ultrastructures. These images were produced using proximity imaging in which a 5-ns pulse of soft x-rays with wavelengths near and inside the water windows (23A-44A) produced by the laser-plasma were absorbed by the specimen and then registered on a photo resist. The x-ray images imprinted on the photo resist were then developed and analyzed with an atomic force microscope (AFM). Mouse thioglycollate-elicited peritoneal macrophages in suspension were examined by this new x-ray microscope. The x-ray images of the macrophages were compared with those observed by conventional transmission electron microscopy (TEM). The x-ray images showed no obvious organelles, including the nucleus and endoplasmic reticulum, as can be seen with TEM, but high- and low-contrast structures caused by mass distribution of carbon were observed. Thus, using the x-ray microscopy we visualized the first x-ray images of macrophage ultrastructures. The successful x-ray imaging of macrophage ultrastructure indicates that proximity x-ray microscopy may be of value in studying physiology linked to the dynamics of a cell.
利用台式钕玻璃激光系统，开发了一种紧凑、高分辨率的激光等离子体X射线接触显微镜方法。该X射线显微镜系统用于观察巨噬细胞超微结构。这些图像是通过近场成像产生的，其中由激光等离子体产生的波长接近水窗（23埃-44埃）及其内部的5纳秒软X射线脉冲被样品吸收，然后记录在光刻胶上。然后，对光刻胶上的X射线图像进行显影，并用原子力显微镜（AFM）进行分析。用这种新型X射线显微镜检查了悬浮在小鼠腹腔中的巯基乙酸诱导的巨噬细胞。将巨噬细胞的X射线图像与通过传统透射电子显微镜（TEM）观察到的图像进行了比较。X射线图像中没有显示出像TEM中那样明显的细胞器，包括细胞核和内质网，但观察到了由碳的质量分布引起的高对比度和低对比度结构。因此，我们利用X射线显微镜观察到了巨噬细胞超微结构的首张X射线图像。巨噬细胞超微结构的成功X射线成像表明，近场X射线显微镜在研究与细胞动力学相关的生理学方面可能具有价值。
