Department of Mechanical Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro. Nam-Gu, Pohang, Gyeong-buk 37673, Republic of Korea.
EXOSOMEplus Inc., Suwon, Gyeonggi-do 16229, Republic of Korea.
ACS Nano. 2021 Jul 27;15(7):11753-11761. doi: 10.1021/acsnano.1c02556. Epub 2021 Jun 28.
We demonstrate a fluorescence-based nanoparticle tracking analysis (NTA) system for the characterization of both the size and membrane protein expression of individual extracellular vesicles (EVs). A sheet of lasers with four different wavelengths was sequentially shone onto extracellular vesicles according to a preprogrammed schedule, providing scattering images intercalated by three fluorescent images. The presence of extracellular vesicles was tracked frame by frame from scattering images. Fluorescence-labeled membrane proteins on EVs were detected by comparing scattering and fluorescent images. The tetraspanins (CD9, CD63, and CD81) of individual HEK293 EVs analyzed by both NTA and total internal reflection fluorescence microscopy showed that the proposed NTA system can contribute to the understanding of individual extracellular vesicles.
我们展示了一种基于荧光的纳米颗粒跟踪分析（NTA）系统，用于表征单个细胞外囊泡（EV）的大小和膜蛋白表达。根据预设的时间表，一束带有四个不同波长的激光依次照射到细胞外囊泡上，提供散射图像和三个荧光图像交错的图像。通过比较散射和荧光图像，从散射图像中逐帧跟踪细胞外囊泡的存在。荧光标记的 EV 上的膜蛋白通过比较散射和荧光图像进行检测。通过 NTA 和全内反射荧光显微镜分析的单个 HEK293 EV 的四跨膜蛋白（CD9、CD63 和 CD81）表明，所提出的 NTA 系统有助于理解单个细胞外囊泡。
