Department of Chemistry and Center for Optical Materials Science and Engineering Technologies, Clemson University, Clemson, South Carolina 29634, USA.
J Am Chem Soc. 2009 Dec 30;131(51):18410-4. doi: 10.1021/ja907228q.
Small ( approximately 15 nm diameter), highly fluorescent conjugated polymer nanoparticles were evaluated for nanoscale 2D and 3D tracking applications. Nanoparticles composed of conjugated polymers possess high absorption cross sections, high radiative rates, and low or moderate aggregation quenching, resulting in extraordinarily high fluorescent brightness. The bright fluorescence ( approximately 200 000 photons detected per particle per 20 ms exposure) yields a theoretical particle tracking uncertainty of less than 1 nm. A lateral tracking uncertainty of 1-2 nm was determined from analysis of trajectories of fixed and freely diffusing particles. Axial (Z) position information for 3D particle tracking was obtained by defocused imaging. Nanoscale tracking of single particles in fixed cells was demonstrated, and a range of complex behaviors, possibly due to binding/unbinding dynamics, were observed.
我们评估了小（直径约 15nm）、高荧光的共轭聚合物纳米粒子在纳米级 2D 和 3D 追踪应用中的性能。由共轭聚合物组成的纳米粒子具有高吸收截面、高辐射速率以及低或中等聚集猝灭，从而产生极高的荧光亮度。明亮的荧光（每粒 20ms 曝光检测到约 200000 个光子）产生的理论粒子追踪不确定度小于 1nm。通过对固定和自由扩散粒子轨迹的分析，确定了 1-2nm 的横向追踪不确定度。通过离焦成像获得了 3D 粒子追踪的轴向（Z）位置信息。我们演示了在固定细胞中单粒子的纳米级追踪，并观察到一系列复杂的行为，可能是由于结合/解结合动力学所致。
