Institut fur Rontgenphysik, Universitat Gottingen, Friedrich-Hund-Platz 1, 37077 Gottingen, Germany.
Biointerphases. 2008 Jun;3(2):FB44. doi: 10.1116/1.2976445.
This article addresses the lateral organization of two-component lipid membranes deposited on a solid support with the addition of colloidal particles. The authors have applied synchrotron-based scanning transmission soft x-ray spectromicroscopy to image thin lipid layer patches with bound microspheres coated by a charged monolayer. The ability and current limits of scanning transmission x-ray spectromicroscopy to examine samples under physiologically relevant conditions in the presence of excess water have been tested. In particular, the authors have investigated a range of model lipids and have shown that these can be reproducibly identified from the near-edge x-ray absorption fine structure spectra at the carbon K absorption edge. Reference spectra were obtained based on a compact laser-driven plasma source, while the spectromicroscopy data were collected using synchrotron radiation at a lateral resolution of about 60 nm. The authors show that thin lipid layer sensitivity can indeed be reached under physiological conditions and that membrane colloid interaction as well as eventual lateral segregation of lipid components may be probed in the future by this technique.
本文探讨了在固体支撑物上沉积的具有胶体粒子的两亲性脂质双层的侧向组织。作者应用同步辐射扫描传输软 X 射线光谱显微镜对带有结合微球的薄脂质层斑片进行成像，这些微球被带电荷的单层所覆盖。该方法测试了在存在过量水的情况下，扫描传输 X 射线光谱显微镜在生理相关条件下检查样品的能力和当前限制。作者特别研究了一系列模型脂质，并表明可以从碳 K 吸收边缘处的近边 X 射线吸收精细结构光谱中可重复性地识别出这些脂质。参考光谱是基于紧凑的激光驱动等离子体源获得的，而光谱显微镜数据是使用同步辐射在约 60nm 的横向分辨率下收集的。作者表明，在生理条件下确实可以达到薄脂质层的灵敏度，并且将来可以通过该技术探测膜胶体相互作用以及脂质成分的最终侧向分离。
