Enzyme-assisted Construction Of DNA Nanostructures And Their Application In The Synthesis Of Inorganic Nanomaterials

Deoxyribonucleic acid(DNA)is not only a carrier of genetic information in living organisms,but also a building block for nanomaterials.The assembly of large and complex nanostructures has been the direction of DNA nanotechnology researchers.Assembly based on DNA Tiles is currently widely accepted scheme.However,the current nanostructures based on DNA Tiles are mostly simple stacks of the same Tiles.If the combination of Tiles of different shapes and sizes is realized,the complexity of the nanostructures will be greatly improved.DNA Origami Tiles is a good structural unit because of its simple assembly process and various shapes.However,the size of DNA Origami Tiles is limited by the length of its scaffold DNA,and the staple strands between different shapes of DNA Origami Tiles cannot be reused,increasing the difficulty of DNA sequence design.With the development of DNA nanotechnology,a variety of nanostructures have been successfully constructed,and the editability of its shape has attracted many researchers to apply it to the preparation of other nanomaterials with controllable morphology,successful in metal and organic materials.However,there is currently no effective way to control the shape of widely-used nano-silica.In order to solve these problems,this paper studied the construction of DNA Origami Tiles with different sizes and the application of DNA nanostructures to the controllable preparation of silica nanoparticles:1.By introducing the concept of a single-stranded Tile in DNA Origami,part of staple strands at a specific position in the initial structure(canvas)were selected to anneal with scaffold DNA.The unbound scaffold DNA fragments were degraded by single-strand specific nuclease.This is a new assembly method of DNA nanostructures which enables the assembly of DNA Origami Tiles of different sizes and molecular weights,including simple geometric figures such as rectangles,triangles,trapezoids,special symbols and various hollow patterns.Moreover,some staple strands can be reused between different nanostructures constructed by this method,reducing the burden of sequence design.2.In order to make full use of the shape of DNA nanostructures,we used DNA Origami as templates to control the synthesis of silica.A reagent named TMAPS was used as a bridging molecule between DNA Origami and silica.By this method,the deposition of silica on the surface of DNA Origami was realized in a solution environment.The DNA Origami@SiO2 nanoparticles of various shapes such as a single rectangle,a cylinder,and a triangle are assembled,and the dispersion of the silica nanoparticles in the solution is achieved by adjusting the concentration of Tris in the solution.