Department of Physics, University of Colorado Boulder, Boulder, CO, 80309, USA.
Department of Bioengineering, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA.
Sci Rep. 2019 Jul 31;9(1):11137. doi: 10.1038/s41598-019-47319-w.
We present results for a new type of fiber-coupled stimulated emission depletion (STED) microscope which uses a single fiber to transport STED and excitation light, as well as collect the fluorescence signal. Our method utilizes two higher-order eigenmodes of polarization maintaining (PM) fiber to generate the doughnut-shaped STED beam. The modes are excited with separate beams that share no temporal coherence, yielding output that is independent of fiber bending. We measured the resolution using 45 nm fluorescent beads and found a median bead image size of 116 nm. This resolution does not change as function of fiber bending radius, demonstrating robust operation. We report, for the first time, STED images of fixed biological samples collected in the epi-direction through fiber. Our microscope design shows promise for future use in super-resolution micro-endoscopes and in vivo neural imaging in awake and freely-behaving animals.
我们展示了一种新型的光纤耦合受激发射损耗（STED）显微镜的结果，该显微镜使用单根光纤传输 STED 和激发光，并收集荧光信号。我们的方法利用保偏（PM）光纤的两个更高阶偏振模式来产生环形 STED 光束。这些模式是用单独的光束激发的，它们没有时间相干性，因此输出与光纤弯曲无关。我们使用 45nm 荧光珠测量了分辨率，发现珠的平均图像尺寸为 116nm。该分辨率不会随光纤弯曲半径的变化而变化，表明具有稳健的性能。我们首次报告了通过光纤在 epi 方向收集的固定生物样品的 STED 图像。我们的显微镜设计有望在超分辨率微内窥镜和清醒自由活动动物的体内神经成像中得到应用。
