Over the past decade, DNA nanotechnology has spawned a broad variety of functional nanostructures tailored toward the enabled state at which applications are coming increasingly in view. One of the branches of these applications is in synthetic biology, where the intrinsic programmability of the DNA nanostructures may pave the way for smart task-specific molecular robotics. In brief, the synthesis of the user-defined artificial DNA nano-objects is based on employing DNA molecules with custom lengths and sequences as building materials that predictably assemble together by obeying Watson–Crick base pairing rules. The general workflow of creating DNA nanoshapes is getting more and more straightforward, and some objects can be designed automatically from the top down. The versatile DNA nano-objects can serve as synthetic tools at the interface with biology, for example, in therapeutics and diagnostics as dynamic logic-gated nanopills, light-, pH-, and thermally driven devices. Such diverse apparatuses can also serve as optical polarizers, sensors and capsules, autonomous cargo-sorting robots, rotary machines, precision measurement tools, as well as electric and magnetic-field directed robotic arms. In this review, we summarize the recent progress in robotic DNA nanostructures, mechanics, and their various implementations.

The internal design of DNA nanostructures defines how they behave in different environmental conditions, such as endonuclease‐rich or low‐Mg2+ solutions. Notably, the inter‐helical crossovers that form the core of such DNA objects have a major impact on their mechanical properties and stability. Importantly, crossover design can be used to optimize DNA nanostructures for target applications, especially when developing them for biomedical environments. To elucidate this, two otherwise identical DNA origami designs are presented that have a different number of staple crossovers between neighboring helices, spaced at 42‐ and 21‐ basepair (bp) intervals, respectively. The behavior of these structures is then compared in various buffer conditions, as well as when they are exposed to enzymatic digestion by DNase I. The results show that an increased number of crossovers significantly improves the nuclease resistance of the DNA origami by making it less accessible to digestion enzymes but simultaneously lowers its stability under Mg2+‐free conditions by reducing the malleability of the structures. Therefore, these results represent an important step toward rational, application‐specific DNA nanostructure design.

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Diverse nanopore-based technologies have substantially expanded the toolbox for label-free single-molecule sensing and sequencing applications. Biological protein pores, lithographically fabricated solid-state and graphene nanopores, and hybrid pores are in widespread use and have proven to be feasible devices for detecting amino acids, polynucleotides, and their specific conformations. However, despite the indisputable and remarkable advantages in technological exploration and commercialization of such equipment, the commonly used methods may lack modularity and specificity in characterization of particular phenomena or in development of nanopore-based devices. In this review, we discuss DNA nanopore techniques that harness the extreme addressability, precision, and modularity of DNA nanostructures that can be incorporated as customized gates or plugs into for example lipid membranes, solid-state pores, and nanocapillaries, thus forming advanced hybrid instruments. In addition to these, there exist a number of diverse DNA-assisted nanopore-based detection and analysis methods. Here, we introduce different types of DNA nanostructure-based pore designs and their intriguing properties as well as summarize the extensive collection of current and future technologies and applications that can be realized through combining DNA nanotechnology with common nanopore approaches.

Here, we present a highly parallel fabrication method dubbed biotemplated lithography of inorganic nanostructures (BLIN) that enables large-scale versatile substrate patterning of metallic and semiconducting nanoshapes with various aspect ratios. We demonstrate the feasibility of our method by employing custom DNA origami structures and Tobacco mosaic virus (TMV) as biotemplates for pattern mask formation. Subsequently, we show high-throughput fabrication of plasmonic (Au and Ag), semiconducting (Ge), and metallic (Al and Ti) nanoparticles on substrates such as indium tin oxide coated glass and silicon wafers. The patterning ability of BLIN ranges from ∼10 to 20 nm feature sizes (with DNA origami, dimensions ∼100 nm or less) to micrometer-long nanowires (with TMV). This combination of scales and material freedom could, with further improvements, provide a cost-efficient pathway for the mass production of versatile nanopatterned surfaces with even smaller feature sizes. BLIN presents a major advantage compared to similar, previously reported techniques, as it permits the use of inexpensive and highly convenient substrates such as optical glass while simultaneously imposing minimal material restrictions on the fabricated nanostructures. Therefore, we believe our method can serve as a viable and potent alternative to current state-of-the-art approaches to produce optically active substrates with various applications in plasmonics (resonances at the visible wavelength range), biosensing (surface enhanced Raman spectroscopy), and functional metamaterials.