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Abstract The field of nucleic acid self‐assembly has advanced significantly, enabling the creation of multi‐dimensional nanostructures with precise sizes and shapes. These nanostructures hold great potential for various applications, including biocatalysis, smart materials, molecular diagnosis, and therapeutics. Here, dynamic light scattering (DLS) and nanoparticle tracking analysis (NTA) are employed to investigate DNA origami nanostructures, focusing on size distribution and particle concentration. Compared to DLS, NTA provided higher resolution in size measurement with a smaller full‐width at half‐maximum (FWHM), making it particularly suitable for characterizing DNA nanostructure. To enhance sensitivity, a fluorescent NTA method is developed by incorporating an intercalation dye to amplify the fluorescence signals of DNA origami. This method is validated by analyzing various DNA origami structures, ranging from 1 and 2D flexible structures to 3D compact shapes, and evaluating structural assembly yields. Additionally, NTA is used to analyze dynamic DNA nanocages that undergo conformational switches among linear, square, and pyramid shapes in response to the addition of trigger strands. Quantitative size distribution data is crucial not only for production quality control but also for providing mechanistic insights into the various applications of DNA nanomaterials. 

The ability to fabricate precisely patterned metal nanoclusters with nanoscale resolution is important for advancing applications in heterogeneous catalysis, biosensing, and nanoscale optical and electronic circuits. Here, we report a simple yet efficient approach for constructing metal nanoclusters with customized shapes on 2D DNA origami templates. Our approach leverages the regiospecific functionalization of DNA origami scaffolds with reactive chemical entities that serve as reduction centers for in situ synthesis of metal nanoclusters. We also demonstrate the hierarchical assembly of individual metallized DNA origami units into well‐defined higher‐order architectures. This work advances the development of DNA origami templated platforms for constructing programable, high‐resolution nanodevices in electronic and optical applications. 

Abstract Hydrophobic interactions are one of the fundamental driving forces of self‐assembly in living systems. It remains challenging to harness hydrophobicity to have a controllable and programmable assembly of DNA nanostructures. On the other hand, there is also a need to explore orthogonal hierarchical assembly strategies to be used as an additional toolset along with the traditional Watson–Crick base pairing to achieve complex superstructures. In this work, we rationally design and synthesize a series of low molecular weight hydrophobic molecules that are conjugated to single‐stranded DNA strands. By incorporating these modified DNA strands into the precisely defined locations of DNA tiles and origami nanostructures, we achieve controlled hierarchical assembly driven by hydrophobic interaction. We demonstrate a versatile hydrophobicity‐guided higher‐order assembly strategy by employing strategically engineered DNA nanostructures of increasing complexity, ranging from simple DNA tiles to complex origami structures, functionalized with these small hydrophobic molecules as programmable building blocks.