Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA.
Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois 60607-7061, USA.
J Chem Phys. 2021 Oct 28;155(16):164201. doi: 10.1063/5.0063634.
A microscopy platform that leverages the arrival time of individual photons to enable 3D single-particle tracking of fast-moving (translational diffusion coefficient of ≃3.3 µm/s) particles in high-background environments is reported here. It combines a hardware-based time-gating module, which enables the rate of photon processing to be as high as 100 MHz, with a two-photon-excited 3D single-particle tracking confocal microscope to enable high sample penetration depth. Proof-of-principle experiments where single quantum dots are tracked in solutions containing dye-stained cellulose, are shown with tracking performance markedly improved using the hardware-based time-gating module. Such a microscope design is anticipated to be of use to a variety of communities who wish to track single particles in cellular environments, which commonly have high fluorescence and scattering background.
这里报道了一种利用单光子到达时间的显微镜平台，可实现高背景环境中快速移动（平移扩散系数 ≃3.3 µm/s）粒子的 3D 单颗粒跟踪。它结合了基于硬件的时间门控模块，可将光子处理速率提高到 100 MHz，以及双光子激发的 3D 单颗粒跟踪共焦显微镜，可实现高样品穿透深度。通过在含有染料染色纤维素的溶液中跟踪单量子点的原理验证实验，展示了使用基于硬件的时间门控模块显著改善的跟踪性能。这种显微镜设计有望被希望在细胞环境中跟踪单个粒子的各种研究领域所使用，因为细胞环境通常具有高荧光和散射背景。
