Mariella R, van den Engh G, Masquelier D, Eveleth G
Lawrence Livermore National Laboratory, Livermore, California 94551, USA.
Cytometry. 1996 May 1;24(1):27-31. doi: 10.1002/(SICI)1097-0320(19960501)24:1<27::AID-CYTO3>3.0.CO;2-F.
We report a new physical configuration for the detection of perpendicular light scatter or fluorescence in flow cytometry when using a fluid stream in air. This configuration increases the signal-to-noise ratio and narrows the coefficient of variation for uniformly sized latex spheres when compared to using a microscope objective to collect such light. The new technique views the scattered light that is trapped within the optical waveguide that is naturally formed by the flow stream in air. One efficient and simple way to detect the light trapped within this optical waveguide is to place one end of a fiber optic, with a conically polished tip and sufficiently large-core diameter, directly into the flow stream and to place an optical detector at the fiber's other end. For perpendicular light scatter, the flow-stream waveguide achieves high collection efficiency (NA = 0.88) as well as high efficiency of optical through put due to lack of surfaces between the light scatterers and the detector. We obtained 10-fold higher signals with this technique than with a long-working-distance microscope objective. The flow-stream waveguide is also much easier to align than traditional microscope-lens-based systems.
我们报告了一种新的物理配置，用于在流式细胞术中使用空气中的流体流检测垂直光散射或荧光。与使用显微镜物镜收集此类光相比，这种配置提高了信噪比，并缩小了均匀大小乳胶球的变异系数。新技术观察被困在由空气中的流体流自然形成的光波导内的散射光。检测被困在该光波导内的光的一种有效且简单的方法是将一端具有锥形抛光尖端且芯径足够大的光纤直接放入流体流中，并在光纤的另一端放置一个光学探测器。对于垂直光散射，流体流波导由于光散射体与探测器之间没有表面，实现了高收集效率（NA = 0.88）以及高光学透过效率。使用这种技术我们获得的信号比使用长工作距离显微镜物镜高10倍。流体流波导也比传统的基于显微镜透镜的系统更容易对准。
