3D DNA Self-Assembly Algorithmic Model to Solve the Hamiltonian Path Problem

Self-assembly reveals the innate character of DNA computing, DNA self-assembly is regarded as the best way to make DNA computing transform into computer chip. This paper introduces a strategy of DNA 3D self-assembly algorithm to solve the Hamiltonian Path Problem. Firstly, I introduced a non-deterministic algorithm. Then, according to the algorithm I designed the types of DNA tiles which the computing process needs. Lastly, I demonstrated the self-assembly process and the experimental methods which can get the final result. The computing time is linear, and the number of the different tile types is constant.

Constructing Large 2D Lattices Out of DNA-Tiles

The predictable nature of deoxyribonucleic acid (DNA) interactions enables assembly of DNA into almost any arbitrary shape with programmable features of nanometer precision. The recent progress of DNA nanotechnology has allowed production of an even wider gamut of possible shapes with high-yield and error-free assembly processes. Most of these structures are, however, limited in size to a nanometer scale. To overcome this limitation, a plethora of studies has been carried out to form larger structures using DNA assemblies as building blocks or tiles. Therefore, DNA tiles have become one of the most widely used building blocks for engineering large, intricate structures with nanometer precision. To create even larger assemblies with highly organized patterns, scientists have developed a variety of structural design principles and assembly methods. This review first summarizes currently available DNA tile toolboxes and the basic principles of lattice formation and hierarchical self-assembly using DNA tiles. Special emphasis is given to the forces involved in the assembly process in liquid-liquid and at solid-liquid interfaces, and how to master them to reach the optimum balance between the involved interactions for successful self-assembly. In addition, we focus on the recent approaches that have shown great potential for the controlled immobilization and positioning of DNA nanostructures on different surfaces. The ability to position DNA objects in a controllable manner on technologically relevant surfaces is one step forward towards the integration of DNA-based materials into nanoelectronic and sensor devices.

Mechanical and Electrical Properties of DNA Hydrogel-Based Composites Containing Self-Assembled Three-Dimensional Nanocircuits

Molecular self-assembly of DNA has been developed as an effective construction strategy for building complex materials. Among them, DNA hydrogels are known for their simple fabrication process and their tunable properties. In this study, we have engineered, built, and characterized a variety of pure DNA hydrogels using DNA tile-based crosslinkers and different sizes of linear DNA spacers, as well as DNA hydrogel/nanomaterial composites using DNA/nanomaterial conjugates with carbon nanotubes and gold nanoparticles as crosslinkers. We demonstrate the ability of this system to self-assemble into three-dimensional percolating networks when carbon nanotubes and gold nanoparticles are incorporated into the DNA hydrogel. These hydrogel composites showed interesting non-linear electrical properties. We also demonstrate the tuning of rheological properties of hydrogel-based composites using different types of crosslinkers and spacers. The viscoelasticity of DNA hydrogels is shown to dramatically increase by the use of a combination of interlocking DNA tiles and DNA/carbon nanotube crosslinkers. Finally, we present measurements and discuss electrically conductive nanomaterials for applications in nanoelectronics.

The Design and Application of Exclusive OR Logical Computation Based on DNA 3-Arm Sub-Tile Self-Assembly

DNA algorithmic self-assembly plays a vital role in DNA computing, which is applied to create new DNA tiles and then guides these tiles into an algorithmic lattice. However, the larger the logical calculation scale is, the more tile sets will be needed, so that computing model design and experiment will be increasingly difficult. This paper presents a new DNA ‘3-arm sub-tile strategy’ that constructs XOR and half-adder logical circuits. The types of DNA tile corresponding to the logical values is unified in DNA XOR and half-adder logical circuits, which have only three kinds of DNA tiles: logic ‘0’, logic ‘1’ and fixation tile. Compared with the previous references, the amount of DNA tile types has been greatly reduced. Moreover, the half-adder molecular circuit has a distinctive feature, which is an application of the expansion of the XOR logic circuit. Meanwhile, a set of DNA 3-arm sub-tiles suitable for half-adder logical computation is designed on the NUPACK online server. The simulated experiments show that the correct rate of base pairing of the designed DNA encoding is high and the structures are stable. The DNA 3-arm sub-tile self-assembly methods provide a new way to form DNA logical circuits, and has a great potential in the expansion of the integrated circuits.

Adenita: interactive 3D modelling and visualization of DNA nanostructures

DNA nanotechnology is a rapidly advancing field, which increasingly attracts interest in many different disciplines, such as medicine, biotechnology, physics and biocomputing. The increasing complexity of novel applications requires significant computational support for the design, modelling and analysis of DNA nanostructures. However, current in silico design tools have not been developed in view of these new applications and their requirements. Here, we present Adenita, a novel software tool for the modelling of DNA nanostructures in a user-friendly environment. A data model supporting different DNA nanostructure concepts (multilayer DNA origami, wireframe DNA origami, DNA tiles etc.) has been developed allowing the creation of new and the import of existing DNA nanostructures. In addition, the nanostructures can be modified and analysed on-the-fly using an intuitive toolset. The possibility to combine and re-use existing nanostructures as building blocks for the creation of new superstructures, the integration of alternative molecules (e.g. proteins, aptamers) during the design process, and the export option for oxDNA simulations are outstanding features of Adenita, which spearheads a new generation of DNA nanostructure modelling software. We showcase Adenita by re-using a large nanorod to create a new nanostructure through user interactions that employ different editors to modify the original nanorod.

Operation of Queue and Stack by DNA Tiles

DNA is used as self-nanomaterials to assemble into specific structures. DNA tile provides a new idea for the application of DNA tile in the field of computing. Recent years, Queue and Stack are important linear data structures which are used in various software systems widely. The implementation of DNA based queue and stack has been studied continuously for many years. In the traditional DNA computing, queue and stack are mostly realized by DNA strands displacement, restriction endonuclease and ligase were used. However, as an active material, it has a high requirement for enzyme experimental conditions. The purpose of this paper is to implement queue and stack structures using non-enzyme systems. The rule of Queue is characterized by FIFO (first in first out), which allows for insertion at one end of the list and deletion at the other. The rule of Stack is characterized by FILO(first in last out), which allows for insertion and deletion at one end of the list. We are aimed to implement Queue and Stack using self-assembly and disassembly via DNA Tiles. No enzymes are needed for the whole experiment. As an enzyme-free system, it provides a new method to implement stack and queue.

Adenita: Interactive 3D modeling and visualization of DNA Nanostructures

We present Adenita, a novel software tool for the design of DNA nanostructures in a user-friendly integrated environment for molecular modeling. Adenita is capable of handling large DNA origami structures, re-use them as building blocks of new designs and provide on demand feedback, thus overcoming effectively some of the limitations of existing tools. Additionally, it integrates all major established approaches to DNA nanostructure design (DNA origami, wireframe nanostructures and DNA tiles) and allows to combine them. We show-case Adenita by re-using a large nanorod designed with Cadnano [1] to create a new nanostructure through user interactions that employ different editors to modify the original nanorod.