Department of Biomedical Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 510855, China.
Nanoscale. 2020 Apr 14;12(14):7522-7526. doi: 10.1039/d0nr00347f. Epub 2020 Mar 26.
Super-resolution optical fluctuation imaging (SOFI) produces fast, background-free, super-resolved images by analyzing the temporal fluorescence fluctuations of independent emitters. With sufficient brightness and fluctuations, a higher order of image processing affords a higher resolution and in principle the resolution enhancement is unbounded. However, it is practically challenging to find suitable probes for high-order SOFI. Herein, we report two types of BODIPY-based polymer dots (Pdots) with narrow-band emissions, pronounced fluctuations, and prominent photostability, thus enabling high-order, dual-color SOFI nanoscopy. Single-particle and subcellular SOFI analysis reveals the superior performance of the BODIPY Pdots as compared to conventional streptavidin-conjugated Alexa dyes. In contrast with wide-field images, the spatial resolution (∼57 nm) was enhanced by ∼6.0-fold in 8-order single-particle SOFI nanoscopy. A spatial resolution (61 nm) was obtained for single microtubules labeled by the BODIPY Pdots, while the majority of the subcellular structures were lost for those labeled by streptavidin-Alexa dyes in 8-order SOFI. This work indicates the unprecedented performance of Pdot probes for multi-color subcellular SOFI applications.
超分辨率光学波动成像（SOFI）通过分析独立发射器的时间荧光波动来产生快速、无背景、超分辨率的图像。具有足够的亮度和波动时，更高阶的图像处理可提供更高的分辨率，并且原则上分辨率增强是无限制的。然而，实际上很难找到适合高阶 SOFI 的合适探针。在此，我们报告了两种基于 BODIPY 的聚合物点（Pdots），它们具有窄带发射、明显的波动和突出的光稳定性，从而能够实现高阶双色 SOFI 纳米显微镜。单粒子和亚细胞 SOFI 分析表明，与传统的链霉亲和素偶联 Alexa 染料相比，BODIPY Pdots 的性能更优。与宽场图像相比，在 8 阶单粒子 SOFI 纳米显微镜中，空间分辨率（约 57nm）提高了约 6.0 倍。通过 BODIPY Pdots 标记的单个微管获得了 61nm 的空间分辨率，而用链霉亲和素-Alexa 染料标记的大多数亚细胞结构在 8 阶 SOFI 中丢失。这项工作表明 Pdot 探针在多色亚细胞 SOFI 应用中具有前所未有的性能。
