Department of Chemistry, 930 N. University Avenue, University of Michigan, Ann Arbor, Michigan 48109-1055, USA.
Nano Lett. 2013 Feb 13;13(2):728-33. doi: 10.1021/nl304415b. Epub 2013 Jan 31.
We employ the single-particle fluorescence nanoscopy technique points accumulation for imaging in nanoscale topography (PAINT) using site-specific DNA probes to acquire two-dimensional density maps of specific features patterned on nanoscale DNA origami pegboards. We show that PAINT has a localization accuracy of ~10 nm that is sufficient to reliably distinguish dense (>10(4) features μm(-2)) sub-100 nm patterns of oligonucleotide features. We employ two-color PAINT to follow enzyme-catalyzed modification of features on individual origami and to show that single nanopegboards exhibit stable, spatially heterogeneous probe-binding patterns, or "fingerprints." Finally, we present experimental and modeling evidence suggesting that these fingerprints may arise from feature spacing variations that locally modulate the probe binding kinetics. Our study highlights the power of fluorescence nanoscopy to perform quality control on individual soft nanodevices that interact with and position reagents in solution.
我们采用单粒子荧光纳米显微镜技术点积累成像纳米形貌(PAINT),使用特定于位置的 DNA 探针获取在纳米尺度 DNA 折纸钉板上图案化的特定特征的二维密度图。我们表明,PAINT 的定位精度约为 10nm,足以可靠地区分密集(>10^4 个特征/μm^-2)的小于 100nm 的寡核苷酸特征图案。我们采用双色 PAINT 来跟踪酶催化的单个折纸特征的修饰,并表明单个纳米钉板表现出稳定的、空间异质的探针结合模式,或“指纹”。最后,我们提出了实验和建模证据表明,这些指纹可能是由局部调节探针结合动力学的特征间距变化引起的。我们的研究强调了荧光纳米显微镜在对与溶液中的试剂相互作用并定位试剂的单个软纳米器件进行质量控制方面的强大功能。