Structural DNA nanotechnology provides unique, well-controlled, versatile, and highly addressable motifs and templates for assembling materials at the nanoscale. These methods to build from the bottom-up using DNA as a construction material are based on programmable and fully predictable Watson-Crick base pairing. Researchers have adopted these techniques to an increasing extent for creating numerous DNA nanostructures for a variety of uses ranging from nanoelectronics to drug-delivery applications. Recently, an increasing effort has been put into attaching nanoparticles (the size range of 1–20 nm) to the accurate DNA motifs and into creating metallic nanostructures (typically 20–100 nm) using designer DNA nanoshapes as molds or stencils. By combining nanoparticles with the superior addressability of DNA-based scaffolds, it is possible to form well-ordered materials with intriguing and completely new optical, plasmonic, electronic, and magnetic properties. This focused review discusses the DNA structure-directed nanoparticle assemblies covering the wide range of different one-, two-, and three-dimensional systems.

DNA origami is used to direct the formation of well-ordered 3D nanoparticle superlattices held together by electrostatic interactions.

Lipids are important building blocks in cellular compartments,a nd therefore their self-assembly into welldefined hierarchicals tructures has gained increasing interest. Cationic lipids and unstructured DNAc an co-assemble into highly ordered structures (lipoplexes), but potential applications of lipoplexes are still limited. Using scaffolded DNA origami nanostructures could aid in resolving these drawbacks. Here,w eh ave complexed DNAo rigami together with ac ationic lipid 1,2-dioleoly-3-trimethylammonium-propane (DOTAP) and studied their self-assembly driven by electrostatic and hydrophobic interactions.The results suggest that the DNAo rigami function as templates for the growth of multilamellar lipid structures and that the DNAo rigami are embedded in the formed lipid matrix. Furthermore,t he lipid encapsulation was found to significantly shield the DNA origami against nuclease digestion. The presented complexation strategy is suitable for aw ide range of DNA-based templates and could therefore find uses in construction of cellmembrane-associated components.

Hierarchical assembly of programmable DNA frameworkssuch as DNA origamipaves the way for versatile nanometer-precise parallel nanopatterning up to macroscopic scales. As of now, the rapid evolution of the DNA nanostructure design techniques and the accessibility of these methods provide a feasible platform for building highly ordered DNA-based assemblies for various purposes. So far, a plethora of different building blocks based on DNA tiles and DNA origami have been introduced, but the dynamics of the large-scale lattice assembly of such modules is still poorly understood. Here, we focus on the dynamics of two-dimensional surface-assisted DNA origami lattice assembly at mica and lipid substrates and the techniques for prospective three-dimensional assemblies, and finally, we summarize the potential applications of such systems.

Cationic phthalocyanines bind DNA origami nanostructures, which protects them against enzymatic degradation and enhances the optical properties of the phthalocyanines.

DNA nanotechnology enables straightforward fabrication of user-defined and nanometer-precise templates for a cornucopia of different uses. To date, most of these DNA assemblies have been static, but dynamic structures are increasingly coming into view. The programmability of DNA not only allows for encoding of the DNA object shape but also it may be equally used in defining the mechanism of action and the type of stimuli-responsiveness of the dynamic structures. However, these “robotic” features of DNA nanostructures are usually demonstrated for only small, discrete, and device-like objects rather than for collectively behaving higher-order systems. Here, we show how a large-scale, two-dimensional (2D) and pH-responsive DNA origami-based lattice can be assembled into two different configurations (“open” and “closed” states) on a mica substrate and further switched from one to the other distinct state upon a pH change of the surrounding solution. The control over these two configurations is achieved by equipping the arms of the lattice-forming DNA origami units with “pH-latches” that form Hoogsteen-type triplexes at low pH. In short, we demonstrate how the electrostatic control over the adhesion and mobility of the DNA origami units on the surface can be used both in the large lattice formation (with the help of directed polymerization) and in the conformational switching of the whole lattice. To further emphasize the feasibility of the method, we also demonstrate the formation of pH-responsive 2D gold nanoparticle lattices. We believe this work can bridge the nanometer-precise DNA origami templates and higher-order large-scale systems with the stimuli-induced dynamicity.

Lipids are important building blocks in cellular compartments, and therefore their self‐assembly into well‐defined hierarchical structures has gained increasing interest. Cationic lipids and unstructured DNA can co‐assemble into highly ordered structures (lipoplexes), but potential applications of lipoplexes are still limited. Using scaffolded DNA origami nanostructures could aid in resolving these drawbacks. Here, we have complexed DNA origami together with a cationic lipid 1,2‐dioleoly‐3‐trimethylammonium‐propane (DOTAP) and studied their self‐assembly driven by electrostatic and hydrophobic interactions. The results suggest that the DNA origami function as templates for the growth of multilamellar lipid structures and that the DNA origami are embedded in the formed lipid matrix. Furthermore, the lipid encapsulation was found to significantly shield the DNA origami against nuclease digestion. The presented complexation strategy is suitable for a wide range of DNA‐based templates and could therefore find uses in construction of cell‐membrane‐associated components.

DNA nanotechnology enables straightforward fabrication of user-defined and nano-meter-precise templates for a cornucopia of different uses. To date, most of these DNA assemblies have been static, but dynamic structures are increasingly coming into view. The programmability of DNA not only allows encoding of the DNA object shape, but it may be equally used in defining the mechanism of action and the type of stimuli- responsiveness of the dynamic structures. However, these "robotic" features of DNA nanostructures are usually demonstrated for only small, discrete and device-like objects rather than for collectively behaving higher-order systems. Here, we show how a large- scale, two-dimensional (2D) and pH-responsive DNA origami -based lattice can be assembled on a mica substrate and further reversibly switched between two distinct states upon the pH change of the surrounding solution. The control over these two configurations is achieved by equipping the arms of the lattice-forming DNA origami units with "pH-latches" that form Hoogsteen-type triplexes at low pH. In a nutshell, we demonstrate how the electrostatic control over the adhesion and mobility of the DNA origami units on the surface can be used both in the large lattice formation (with the help of directed polymerization) and in the conformational switching of the whole lattice on the substrate. To further emphasize the feasibility of the method, we also demonstrate the formation of reconfigurable 2D gold nanoparticle lattices. We believe this work serves as an important milestone in bridging the nanometer-precise DNA origami templates and higher-order large-scale systems with the stimuli-induced dynamicity.