Zhang P, Goodwin P M, Werner J H
Appl Opt. 2014 Nov 1;53(31):7415-21. doi: 10.1364/AO.53.007415.
Interferometric detection of the fluorescence emission from a single molecule [interferometric photoactivated localization microscopy (iPALM)] enables a localization accuracy of nanometers in axial localization for 3D superresolution imaging. However, iPALM uses two high-numerical-aperture (NA) objectives in juxtaposition for fluorescence collection (a 4Pi microscope geometry), increasing expense and limiting samples that can be studied. Here, we propose an interferometric single molecule localization microscopy method using a single high-NA objective. The axial position of single molecules can be unambiguously determined from the phase-shifted interference signals with nanometer precision and over a range of 2λ. The use of only one objective simplifies the system configuration and sample mounting. In addition, due to the use of wavefront-splitting interference in our approach, the two parts of the wavefront that eventually merge and interfere with each other travel along nearly equivalent optical paths, which should minimize the effect of drift for long-term 3D superresolution imaging.
通过干涉测量法检测单分子的荧光发射[干涉光活化定位显微镜(iPALM)]，可实现3D超分辨率成像中轴向定位的纳米级定位精度。然而，iPALM使用两个并列的高数值孔径(NA)物镜进行荧光收集(4Pi显微镜结构)，这增加了成本并限制了可研究的样本。在此，我们提出一种使用单个高NA物镜的干涉单分子定位显微镜方法。单分子的轴向位置可以通过纳米精度的相移干涉信号明确确定，范围可达2λ。仅使用一个物镜简化了系统配置和样品安装。此外，由于我们的方法中使用了波前分割干涉，最终合并并相互干涉的波前的两部分沿着几乎等效的光路传播，这应该会使长期3D超分辨率成像的漂移影响最小化。
