Leibniz Institute of Photonic Technology, Albert-Einstein-Str. 9, 07745 Jena, Germany.
Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States.
ACS Sens. 2020 Mar 27;5(3):879-886. doi: 10.1021/acssensors.0c00339. Epub 2020 Mar 6.
Tracking and analyzing the individual diffusion of nanoscale objects such as proteins and viruses is an important methodology in life science. Here, we show a sensor that combines the efficiency of light line illumination with the advantages of fluidic confinement. Tracking of freely diffusing nano-objects inside water-filled hollow core fibers with core diameters of tens of micrometers using elastically scattered light from the core mode allows retrieving information about the Brownian motion and the size of each particle of the investigated ensemble individually using standard tracking algorithms and the mean squared displacement analysis. Specifically, we successfully measure the diameter of every gold nanosphere in an ensemble that consists of several hundreds of 40 nm particles, with an individual precision below 17% (±8 nm). In addition, we confirm the relevance of our approach with respect to bioanalytics by analyzing 70 nm λ-phages. Overall these features, together with the strongly reduced demand for memory space, principally allows us to record thousands of frames and to achieve high frame rates for high precision tracking of nanoscale objects.
追踪和分析蛋白质和病毒等纳米级物体的个体扩散是生命科学中的一种重要方法。在这里，我们展示了一种传感器，它结合了光线线照明的效率和流体限制的优势。使用从芯模弹性散射的光，对直径为数十微米的中空光纤内的自由扩散纳米物体进行追踪，允许使用标准追踪算法和均方根位移分析，分别获取关于每个被研究粒子的布朗运动和大小的信息。具体来说，我们成功地测量了由几百个 40nm 粒子组成的金纳米球的直径，每个粒子的精度低于 17%（±8nm）。此外，我们通过分析 70nmλ-噬菌体来验证我们的方法在生物分析方面的相关性。总的来说，这些特性，加上对内存空间的需求大大减少，使得我们能够记录数千帧，并实现高帧速率，以实现纳米物体的高精度追踪。
