Construction method of two-dimensional chiral nanoparticle superlattice

Abstract

The invention provides a construction method of a two-dimensional chiral nano superlattice, which comprises the following steps of: treating a silicon substrate by using a plasma cleaning machine to change the hydrophilicity of the silicon substrate; constructing a two-dimensional DNA origami array by using a DNA self-assembly technology; modifying the nano-particles and the nano-rods by using DNA (Deoxyribonucleic Acid); spreading the two-dimensional DNA origami array on the surface of the substrate; and hybridizing the nano particles and the nano rods which are modified by DNA with the two-dimensional DNA origami array to form the two-dimensional chiral nano superlattice. According to the construction method of the two-dimensional chiral nano superlattice, provided by the invention, the capture chain on the DNA origami array is subjected to position design, and the nano particles and the nano rods paired with the capture chain are captured, so that accurate spatial positioning of the nano particles and the nano rods can be realized, namely spatial addressing is realized; therefore, the two-dimensional chiral nano superlattice with specific design can be constructed.

Description

Technical Field

[0001] The invention belongs to the field of nano materials, and in particular relates to a method for preparing a two-dimensional chiral superlattice composed of nano particles. Background Art

[0002] In 1982, Professor Seeman first proposed the concept of using branched DNA molecules with complementary sticky ends to construct two-dimensional ordered arrays. Later, Seeman and his colleagues developed a double-crossover (DX) molecule consisting of two double helices connected by crosses, and successfully constructed it in periodic two-dimensional lattices and tubes. In 2006, Professor Rothemund pioneered the concept of DNA origami, which is to use the self-recognition and binding ability of long DNA chains to achieve the folding of long DNA chains by accurately designing base sequences, and then construct two-dimensional nanostructures with specific shapes, such as rectangles, squares, triangles, stars and even smiley faces. The emergence of this technology marks that DNA nanotechnology has reached an unprecedented height in the construction of complex and precise nanostructures. In recent years, with the continuous advancement of technology and in-depth research, scientists have successfully assembled various inorganic nanomaterials on two-dimensional DNA tiles. Jiang et al. used the programmability of DNA technology to construct two-dimensional DNA arrays of different shapes and sizes; Liedl et al. combined DNA origami self-assembly and surface lithography to successfully deposit DNA origami onto a lithography pattern substrate, thereby creating a large-scale array that can accurately place DNA structures; Bathe et al. used surface-assisted assembly methods to successfully achieve two-dimensional ordered self-assembly of quantum dots and quantum rods on mica sheets. These research results all show that DNA nanotechnology is a very effective means of manufacturing nanostructures.

[0003] Two-dimensional chiral nano-superlattices exhibit unique properties in the fields of optics, electricity, and magnetism. The characteristics of chiral nanostructures enable them to exhibit excellent performance in the selective absorption, scattering, and emission of light. Although existing DNA self-assembly methods have made significant progress in constructing two-dimensional nanostructures, how to flexibly and efficiently use DNA origami technology to assemble nanoparticles into two-dimensional chiral superlattices in a bottom-up manner to achieve highly ordered superlattices with specific chiral characteristics remains a challenge. Summary of the invention

[0004] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a method for constructing a two-dimensional chiral nano superlattice.

[0005] In order to achieve the above-mentioned object of the invention, the present invention adopts the following technical solutions:

[0006] A method for constructing a two-dimensional chiral nano superlattice comprises the following steps: treating a substrate with a plasma cleaning machine to change its hydrophilicity; constructing a two-dimensional DNA array with DNA self-assembly technology; modifying nanoparticles and nanorods with DNA; spreading the two-dimensional DNA array on the surface of the substrate; and hybridizing the nanoparticles and nanorods modified with DNA with the two-dimensional DNA array to form a two-dimensional chiral nano superlattice.

[0007] Preferably, the two-dimensional DNA array of the present invention is assembled using triangular DNA origami as a primitive, with DNA edge chains added and assembled by self-assembly technology, and the size of the triangular DNA origami is 80nm×80nm×80nm×2nm.

[0008] Preferably, the basic triangular DNA origami of the present invention comprises a long single-stranded DNA of 7259 bases extracted from the m13mp18 virus, a group of auxiliary DNA strands and a capture DNA strand, which are folded by pairing the auxiliary DNA strands with the capture DNA strands and the long single-stranded DNA of the m13mp18 virus, wherein the total number of auxiliary DNA strands and capture DNA strands is 168 strands, and the number of bases of any auxiliary strand may be unequal. The capture DNA strand comprises two short sequences S1 and S2, wherein the short sequence S1 participates in the pairing of the m13mp18 virus long single-stranded DNA, and the short sequence S2 is a sticky end for capturing the nanoparticles or nanorods. The DNA edge strands are 24 strands, which are used to assemble the triangular DNA origami into a two-dimensional DNA origami array.

[0009] Preferably, the present invention assembles three two-dimensional nano superlattices with different structures by changing the design of the capture connection sites, and names them as superlattice I, superlattice II and superlattice III respectively.

[0010] Preferably, for superlattice I, any one of the nanorods requires 16 capture chains, and any one of the nanoparticles requires 2 capture chains DNA to capture; for superlattice II, any one of the nanorods requires 16 capture chains, and any one of the nanoparticles requires 2 capture chains DNA to capture; for superlattice III, any one of the nanorods requires 11 capture chains, and any one of the nanoparticles requires 2 capture chains DNA to capture.

[0011] Preferably, after the two-dimensional DNA array is spread on the silica substrate, the present invention needs to wait for 20 minutes, and after the array is stably connected to the substrate, a buffer solution (1×TAE-Mg2+) is used for washing to remove excess DNA chains.

[0012] Preferably, the DNA used in the modification of nanoparticles or nanorods with DNA in the present invention is thiol-modified DNA.

[0013] Preferably, the nanoparticles of the present invention are gold nanoparticles, and the nanorods are gold nanorods.

[0014] Preferably, the present invention further comprises a step of removing excess DNA after modifying the nanoparticles or nanorods with DNA.

[0015] Preferably, the step of removing excess DNA in the present invention comprises removing excess DNA by 1% agarose electrophoresis.

[0016] Preferably, in the present invention, the hybridization temperature for hybridizing the DNA-modified nanoparticles or nanorods with the two-dimensional DNA array is lower than the melting temperature of the two-dimensional DNA array.

[0017] By adopting the above technical solution, the beneficial effects of the present invention are:

[0018] The present invention provides a method for constructing a two-dimensional chiral nano superlattice on a substrate, comprising the following steps: treating a silicon substrate with a plasma cleaning machine to change its hydrophilicity; constructing a two-dimensional DNA origami array with DNA self-assembly technology; modifying nanoparticles and nanorods with DNA; spreading the two-dimensional DNA origami array on the surface of the substrate; hybridizing the DNA-modified nanoparticles and nanorods with the two-dimensional DNA origami array to form a two-dimensional chiral nano superlattice. The method for constructing a two-dimensional chiral nano superlattice provided by the present invention can realize precise spatial positioning of nanoparticles and nanorods by designing the position of the capture chain on the DNA origami array to capture the nanoparticles and nanorods paired therewith, that is, spatial addressability, so that a two-dimensional chiral nano superlattice of a specific design can be constructed. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1-6 This is a scanning electron microscope photograph of a two-dimensional nano superlattice structure on the surface of a silicon dioxide substrate obtained according to the method provided in Example 1 of the present invention.

[0020] Figure 7-12 This is a scanning electron microscope photograph of a two-dimensional nano superlattice structure on the surface of a silicon dioxide substrate obtained according to the method provided in Example 2 of the present invention. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0022] A method for constructing a two-dimensional chiral nano superlattice utilizes DNA self-assembly technology to construct a two-dimensional DNA array, modifies nanoparticles or nanorods with DNA, and hybridizes the DNA-modified nanoparticles or nanorods with the two-dimensional DNA array to form a two-dimensional chiral nano superlattice.

[0023] Furthermore, the two-dimensional DNA array is assembled with triangular DNA origami as the basic unit, and DNA edge chains are added to form the array through self-assembly technology. The size of the triangular DNA origami is about 80nm×80nm×80nm×2nm.

[0024] Furthermore, the triangular DNA origami is formed by pairing the auxiliary DNA with the capture DNA and the long single-stranded DNA of the m13mp18 virus, using a long single-stranded DNA of 7259 bases extracted from the m13mp18 virus, and a group of auxiliary DNA and capture DNA. The total number of auxiliary DNA and capture DNA is 168, and the number of bases in any auxiliary DNA may not be equal. The capture DNA includes two short sequences S1 and S2, the short sequence S1 participates in the pairing of the long single-stranded DNA of the m13mp18 virus, and the short sequence S2 is a sticky end for capturing the nanoparticles or nanorods. The DNA edge chains are 24, which are used to assemble the triangular DNA origami into a two-dimensional DNA array.

[0025] Furthermore, by changing the design of the capture connection sites, three two-dimensional nanosuperlattices with different structures were assembled and named superlattice I, superlattice II and superlattice III respectively.

[0026] Furthermore, for superlattice I, any one of the nanorods requires 16 capture chains, and any one of the nanoparticles requires 2 capture chains DNA to capture; for superlattice II, any one of the nanorods requires 16 capture chains, and any one of the nanoparticles requires 2 capture chains DNA to capture; for superlattice III, any one of the nanorods requires 11 capture chains, and any one of the nanoparticles requires 2 capture chains DNA to capture.

[0027] Further, after the two-dimensional DNA array is spread on the silica substrate, it is necessary to wait for 20 minutes, and after the array is stably connected to the substrate, a buffer (1×TAE-Mg2+) is used to wash to remove excess DNA chains. Further, the DNA used to modify the nanoparticles or nanorods with DNA is thiol-modified DNA.

[0028] Furthermore, the nanoparticles are gold nanoparticles, and the nanorods are gold nanorods.

[0029] Furthermore, after the nanoparticles or nanorods are modified with DNA, a step of removing excess DNA is also included.

[0030] Furthermore, the step of removing excess DNA includes removing excess DNA by 1% agarose electrophoresis.

[0031] Furthermore, the hybridization temperature of hybridizing the DNA-modified nanoparticles or nanorods with the two-dimensional DNA origami array is lower than the melting temperature of the two-dimensional DNA array.

[0032] The method for constructing a two-dimensional chiral nano-superlattice provided in the above embodiment of the present invention designs the position of the capture chains on the two-dimensional DNA array to capture the corresponding nanoparticles and nanorods paired therewith, thereby achieving precise spatial positioning of the nanoparticles and nanorods, that is, spatial addressability, thereby constructing a specifically designed two-dimensional chiral nano-superlattice.

[0033] The following is a detailed description of the method for constructing the two-dimensional chiral nano superlattice provided by the above embodiment of the present invention in conjunction with specific embodiments and drawings.

[0034] Example 1

[0035] 1. Construction of two-dimensional DNA arrays using DNA self-assembly technology

[0036] A group of auxiliary chains with a concentration of 100 μM are mixed with the long single-stranded DNA of the m13mp18 virus at a molar ratio of 10:1; then a short-chain DNA for capturing nanorods, namely the capture chain, is added, and the sticky end S2 of the short-chain DNA pairs with the single-stranded DNA on the surface of the nanorod, and another sequence S1 participates in the pairing of the long single-stranded DNA of the m13mp18 virus to form a part of the basic triangular DNA origami, and then the edge chain connecting the basic triangular DNA origami is added, and the molar ratio of the edge chain to the long single-stranded DNA of the m13mp18 virus is 20:1, which is used for self-assembly into a two-dimensional DNA array; then the concentration of the solution is adjusted to 1x TAE-Mg with 50x TAE-Mg solution, and the mixed solution is annealed with a PCR instrument, and the temperature is slowly reduced from 80°C to room temperature after 101 hours to form the required two-dimensional DNA array.

[0037] In this embodiment, the DNA array primitive is preferably a triangular DNA origami of 80nm×80nm×80nm×2nm. The DNA array primitive can also be a two-dimensional DNA origami of other shapes, such as a square, a hexagon, etc.

[0038] In this embodiment, DNA origami is formed by pairing the auxiliary DNA with the capture DNA and the long single-stranded DNA of the m13mp18 virus, a group of auxiliary DNA and capture DNA, and folding the auxiliary DNA with the capture DNA and the long single-stranded DNA of the m13mp18 virus. The total number of the auxiliary DNA and capture DNA is 168, and the number of bases in any of the auxiliary chains may not be equal. The capture DNA includes two short sequences S1 and S2, the short sequence S1 participates in the pairing of the m13mp18 virus long single-stranded DNA, and the short sequence S2 is a sticky end for capturing the nanoparticles or nanorods. The DNA edge chains are 24, which are used to assemble the triangular DNA origami into a two-dimensional DNA origami array.

[0039] In this embodiment, by changing the design of the capture linking sites, three different structures of two-dimensional nano-superlattices were assembled, which were named superlattice I, superlattice II and superlattice III respectively.

[0040] In this embodiment, for superlattice I, any one of the nanorods requires 16 capture links; for superlattice II, any one of the nanorods requires 16 capture links; for superlattice III, any one of the nanorods requires 11 capture links. In the embodiment provided by the present invention, the m13mp18 virus long single-stranded DNA is a single-stranded DNA of 7259 bases extracted from the m13mp18 virus.

[0041] 2. Modifying nanorods with DNA

[0042] The nanorods protected by hexadecyl trimethyl ammonium bromide (CTAB) were centrifuged twice. After the first centrifugation (9000 rpm, 10 minutes), the supernatant was discarded and then reconstituted with ultrapure water. After the second centrifugation (9000 rpm, 10 minutes), DNA was added and frozen (-18°C, 3 hours). After being taken out and thawed, 0.5×TBE-1% SDS was added for reconstitution, and then 5M (mol / L) NaCl solution was slowly added. After 24 hours, the NaCl concentration of the solution became 500mM. The nanorods modified with DNA were electrophoresed by 2% agarose to remove excess DNA, and the required bands were cut out for concentration, and their concentration was measured by UV spectroscopy until the DNA was completely removed to prevent the excess DNA from affecting the precise positioning of the nanorods in the subsequent hybridization steps.

[0043] In this embodiment, the DNA used to modify the nanorods is preferably thiol DNA, so that the binding between the DNA and the nanorods is achieved by utilizing the covalent bond formed between the thiol groups and the nanorods.

[0044] In the embodiment provided by the present invention, the nanorods are preferably gold nanorods.

[0045] 3. Spread the two-dimensional DNA array on the surface of the silicon wafer treated by a plasma cleaner.

[0046] First, the silicon wafer is ultrasonically cleaned with anhydrous ethanol to remove surface dust, and then treated with a plasma cleaner for 15 minutes to change the hydrophilicity of the silicon wafer surface; after taking it out, the self-assembled two-dimensional DNA array is added dropwise to the silicon wafer surface, and waited for 20 minutes for it to be completely adsorbed; then the silicon wafer is rinsed with a buffer solution (1×TAE-Mg2+) to remove incompletely adsorbed and excess DNA chains on the silicon wafer; after it is dried, it is assembled with the purified and modified gold nanorods mentioned above.

[0047] 4. Hybridize the DNA-modified nanorods with the two-dimensional DNA array to form a two-dimensional chiral nanosuperlattice.

[0048] The purified gold nanorods were dropped onto the silicon wafer with the two-dimensional DNA array and placed in an environment of 28°C for 2-3 hours to assemble. Here, the gold nanorod solution should not dry during the assembly process. The excess unassembled gold nanorods were then washed away with a buffer solution (0.5×TBE). It can be understood that the hybridization temperature of the DNA-modified nanorods and the DNA substrate is lower than the melting temperature of the DNA substrate. The position of the gold nanorods is determined by extending the end of the original short-chain DNA (capture chain) on the two-dimensional DNA array to match the DNA sequence on the gold nanoparticles and the gold nanorod surface.

[0049] See also Figures 1 to 6 ,in, Figure 1-2 is a scanning electron microscope photograph of a superlattice I structure on a silicon dioxide substrate obtained by the method provided in Example 1 of the present invention; Figure 3-4 is a scanning electron microscope photograph of a superlattice II structure on a silicon dioxide substrate obtained according to the method provided in Example 1 of the present invention; Figure 5-6 This is a scanning electron microscope photograph of a superlattice III structure on a silicon dioxide substrate obtained by the method provided in Example 1 of the present invention. As can be seen from the figure, the method for constructing a two-dimensional chiral nano superlattice provided in the embodiment of the present invention can achieve precise arrangement of gold nanoparticles and gold nanorods on a two-dimensional array, and simultaneously achieve positioning in two-dimensional space.

[0050] By adopting the method for constructing a two-dimensional chiral nano-superlattice provided in the above embodiment, by designing the position of the capture chain on the DNA array and capturing the nanorods paired therewith, precise spatial positioning of the nanorods can be achieved, that is, spatial addressability can be achieved, thereby constructing a specifically designed two-dimensional chiral nano-superlattice.

[0051] The method for constructing a two-dimensional chiral nano superlattice provided in the above embodiment is adopted, a two-dimensional DNA array is constructed using DNA self-assembly technology, nanorods are modified with DNA, and the nanorods modified with DNA are hybridized with the above two-dimensional DNA array to form a two-dimensional chiral nano superlattice. The method for constructing a two-dimensional chiral nano superlattice provided in the above embodiment of the present invention can realize precise spatial positioning of the nanorods, i.e., spatial addressability, by designing the position of the capture chain on the two-dimensional DNA array to capture the corresponding nanorods paired therewith, so as to construct a two-dimensional chiral nano superlattice of specific design.

[0052] Example 2

[0053] 1. Construction of two-dimensional DNA arrays using DNA self-assembly technology

[0054] A group of auxiliary chains with a concentration of 100 μM are mixed with the long single-stranded DNA of the m13mp18 virus at a molar ratio of 10:1; then a short-chain DNA for capturing nanorods, namely the capture chain, is added, and the sticky end S2 of the short-chain DNA pairs with the single-stranded DNA on the surface of the nanorod, and another sequence S1 participates in the pairing of the long single-stranded DNA of the m13mp18 virus to form a part of the basic triangular DNA origami, and then the edge chain connecting the basic triangular DNA origami is added, and the molar ratio of the edge chain to the long single-stranded DNA of the m13mp18 virus is 20:1, which is used for self-assembly into a two-dimensional DNA array; then the concentration of the solution is adjusted to 1x TAE-Mg with 50x TAE-Mg solution, and the mixed solution is annealed with a PCR instrument, and the temperature is slowly reduced from 80°C to room temperature after 101 hours to form the required two-dimensional DNA array.

[0055] In this embodiment, the DNA array primitive is preferably a triangular DNA origami of 80nm×80nm×80nm×2nm. The DNA array primitive can also be a two-dimensional DNA origami of other shapes, such as a square, a hexagon, etc.

[0056] In this embodiment, DNA origami is formed by pairing the auxiliary DNA with the capture DNA and the long single-stranded DNA of the m13mp18 virus, a group of auxiliary DNA and capture DNA, and folding the auxiliary DNA with the capture DNA and the long single-stranded DNA of the m13mp18 virus. The total number of the auxiliary DNA and capture DNA is 168, and the number of bases in any of the auxiliary chains may not be equal. The capture DNA includes two short sequences S1 and S2, the short sequence S1 participates in the pairing of the m13mp18 virus long single-stranded DNA, and the short sequence S2 is a sticky end for capturing the nanoparticles or nanorods. The DNA edge chains are 24, which are used to assemble the triangular DNA origami into a two-dimensional DNA origami array.

[0057] In this embodiment, by changing the design of the capture linking sites, three different structures of two-dimensional nano-superlattices were assembled, which were named superlattice I*, superlattice II* and superlattice III*.

[0058] In this embodiment, for superlattice I*, any one of the nanorods requires 16 capture chains, and any one of the nanoparticles requires 2 capture chains to capture; for superlattice II*, any one of the nanorods requires 16 capture chains, and any one of the nanoparticles requires 2 capture chains to capture; for superlattice III*, any one of the nanorods requires 11 capture chains, and any one of the nanoparticles requires 2 capture chains to capture. In the embodiment provided by the present invention, the m13mp18 virus long single-stranded DNA is a single-stranded DNA of 7259 bases extracted from the m13mp18 virus.

[0059] 2. Modifying nanorods with DNA

[0060] The nanorods protected by hexadecyl trimethyl ammonium bromide (CTAB) were centrifuged twice. After the first centrifugation (9000 rpm, 10 minutes), the supernatant was discarded and then reconstituted with ultrapure water. After the second centrifugation (9000 rpm, 10 minutes), DNA was added and frozen (-18°C, 3 hours). After being taken out and thawed, 0.5×TBE-1% SDS was added for reconstitution, and then 5M (mol / L) NaCl solution was slowly added. After 24 hours, the NaCl concentration of the solution became 500mM. The nanorods modified with DNA were electrophoresed by 2% agarose to remove excess DNA, and the required bands were cut out for concentration, and their concentration was measured by UV spectroscopy until the DNA was completely removed to prevent the excess DNA from affecting the precise positioning of the nanorods in the subsequent hybridization steps.

[0061] In this embodiment, the DNA used to modify the nanorods is preferably thiol DNA, so that the binding between the DNA and the nanorods is achieved by utilizing the covalent bond formed between the thiol groups and the nanorods.

[0062] In the embodiment provided by the present invention, the nanorods are preferably gold nanorods.

[0063] 3. Modifying Nanoparticles with DNA

[0064] The 40nm nanoparticles synthesized by sodium citrate and DNA were mixed at a molar ratio of 1:300, and PH3 was used to assist the connection. After 10 minutes, 10×TBE was added for centrifugation (the centrifugal speed was 6500 rpm and the centrifugal time was 5 minutes). After the centrifugation, the supernatant was discarded, and then 1×TBE was added to transfer it from the aqueous phase to the TBE phase. DNA was then added to make the molar ratio of gold nanoparticles to DNA reach 1:3000, and frozen (-18°C, 3 hours). After thawing, NaCl solution was added in batches until the final NaCl concentration was 500mM and oscillated for more than 12 hours. The nanorods modified with DNA were electrophoresed by 1% agarose to remove excess DNA, the required bands were cut off and concentrated, and the concentration was measured by UV spectroscopy until the DNA was completely removed to prevent the excess DNA from affecting the precise positioning of the nanoparticles in the subsequent hybridization step.

[0065] In this embodiment, the DNA used to modify the nanoparticles is preferably thiol DNA, so that the covalent bond formed between the thiol group and the nanorods is used to achieve the binding between the DNA and the nanoparticles.

[0066] In this embodiment, the nanoparticles are preferably gold nanoparticles.

[0067] 4. Spread the two-dimensional DNA array on the surface of the silicon wafer treated by a plasma cleaner.

[0068] First, the silicon wafer is ultrasonically cleaned with anhydrous ethanol to remove surface dust, and then treated with a plasma cleaner for 15 minutes to change the hydrophilicity of the silicon wafer surface; after taking it out, the self-assembled two-dimensional DNA array is added dropwise to the silicon wafer surface, and waited for 20 minutes for it to be completely adsorbed; then the silicon wafer is rinsed with a buffer solution (1×TAE-Mg2+) to remove incompletely adsorbed and excess DNA chains on the silicon wafer; after it is dried, it is assembled with the purified and repaired gold nanorods mentioned above.

[0069] 5. Hybridize the DNA-modified gold nanoparticles and nanorods with the two-dimensional DNA array to form a two-dimensional chiral nanosuperlattice.

[0070] The purified gold nanoparticles and gold nanorods are dropped onto the silicon wafer with the two-dimensional DNA array, and placed in an environment of 28°C to assemble for 2-3 hours. Here, during the assembly process, it is necessary to ensure that the gold nanoparticle and gold nanorod solution will not dry up. After that, the excess unassembled gold nanorods are washed away with a buffer solution (0.5×TBE); it can be understood that the hybridization temperature of the DNA-modified gold nanoparticles and nanorods is lower than the melting temperature of the DNA substrate; the positions of the gold nanoparticles and gold nanorods are determined by extending the original short-chain DNA (capture chain) on the two-dimensional DNA array to the DNA pairing sequence on the surface of the gold nanoparticles and gold nanorods. Please refer to Figures 7 to 12 ,in, Figure 7-8 is a scanning electron microscope photograph of a superlattice I* structure on a silicon dioxide substrate obtained by the method provided in Example 2 of the present invention; Figure 9-10 is a scanning electron microscope photograph of a superlattice II* structure on a silicon dioxide substrate obtained by the method provided in Example 2 of the present invention; Figure 11-12 This is a scanning electron microscope photograph of a superlattice III* structure on a silicon dioxide substrate obtained by the method provided in Example 2 of the present invention. As can be seen from the figure, the method for constructing a two-dimensional chiral nano superlattice provided in the embodiment of the present invention can achieve precise arrangement of gold nanoparticles and gold nanorods on a two-dimensional array, and simultaneously achieve positioning in two-dimensional space.

[0071] By adopting the method for constructing a two-dimensional chiral nano-superlattice provided in the above embodiment, by designing the position of the capture chain on the DNA array and capturing the corresponding nanoparticles and nanorods paired therewith, it is possible to achieve precise spatial positioning of the nanoparticles and nanorods, that is, spatial addressability, thereby constructing a specifically designed two-dimensional chiral nano-superlattice.

[0072] The method for constructing a two-dimensional chiral nanosuperlattice provided in the above embodiment is adopted, a two-dimensional DNA array is constructed using DNA self-assembly technology, nanoparticles and nanorods are modified with DNA, and the DNA-modified nanoparticles and nanorods are hybridized with the above-mentioned two-dimensional DNA array to form a two-dimensional chiral nanosuperlattice.

[0073] By adopting the method for constructing a two-dimensional chiral nano-superlattice provided in the above embodiment, by designing the position of the capture chain on the two-dimensional DNA array and capturing the nanoparticles and nanorods paired therewith, it is possible to achieve precise spatial positioning of the nanoparticles and nanorods, that is, spatial addressability, thereby constructing a specifically designed two-dimensional chiral nano-superlattice.

[0074] The above description is only a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been presented as a preferred embodiment as above, it is not intended to limit the present invention. Any technician familiar with the profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A method for constructing a two-dimensional chiral nano superlattice, characterized in that: The steps include: The silicon substrate is treated with a plasma cleaning machine to change its hydrophilicity; Use DNA self-assembly technology to construct two-dimensional DNA arrays; Modification of nanoparticles and nanorods with DNA; spreading the two-dimensional DNA array on the surface of a substrate; The DNA-modified nanoparticles and nanorods are hybridized with the two-dimensional DNA origami array to form a two-dimensional chiral nano superlattice.

2. The method for constructing a two-dimensional chiral nano superlattice according to claim 1, characterized in that: The assembly of the two-dimensional DNA array is based on DNA origami as the basic element, and DNA edge chains are added to form the array through self-assembly. The shape of the DNA origami can be flexibly designed, such as triangle, square, hexagon, etc.

3. The method for constructing a two-dimensional chiral nano superlattice according to claim 2, characterized in that: The basic triangular DNA origami includes a long single-stranded DNA of 7259 bases extracted from the m13mp18 virus, a group of auxiliary chain DNAs and capture chain DNAs, and is folded by pairing the auxiliary chain DNA with the capture chain DNA and the long single-stranded DNA of the m13mp18 virus. The total number of the auxiliary chain DNAs and the capture chain DNAs is 168, and the number of bases in any of the auxiliary chains may not be equal; the capture chain DNA includes two short sequences S1 and S2, the short sequence S1 participates in the pairing of the m13mp18 virus long single-stranded DNA, and the short sequence S2 is a sticky end for capturing the nanoparticles or nanorods; the DNA edge chains are 24, which are used to assemble the triangular DNA origami into a two-dimensional DNA origami array.

4. The method for constructing a two-dimensional chiral nano superlattice according to claim 3, characterized in that: By changing the design of the capture connection sites, three two-dimensional nanosuperlattices with different structures can be assembled, namely superlattice I, superlattice II and superlattice III.

5. The method for constructing a two-dimensional chiral nano superlattice according to claims 3 and 4, characterized in that: For superlattice I, any one of the nanorods requires 16 capture chains, and any one of the nanoparticles requires 2 capture chain DNAs to capture; for superlattice II, any one of the nanorods requires 16 capture chains, and any one of the nanoparticles requires 2 capture chain DNAs to capture; for superlattice III, any one of the nanorods requires 11 capture chains, and any one of the nanoparticles requires 2 capture chain DNAs to capture.

6. The method for constructing a two-dimensional chiral nano superlattice according to claim 1, characterized in that: After the two-dimensional DNA array is spread on the silica substrate, wait for 20 minutes until the array is stably connected to the substrate, and then wash with a buffer to remove excess DNA chains.

7. The method for constructing a two-dimensional chiral nano superlattice according to claim 1, characterized in that: The DNA used to modify the nanoparticles or nanorods is thiol-modified DNA.

8. The method for constructing a two-dimensional chiral nano superlattice according to claim 1 or 7, characterized in that: The nanoparticles and nanorods can be metal, semiconductor, or magnetic particles.

9. The method for constructing a two-dimensional chiral nano superlattice according to claim 1, characterized in that: After the nanoparticles or nanorods are modified with DNA, the method further comprises the step of removing excess DNA; the step of removing excess DNA comprises removing excess DNA by using 1% agarose electrophoresis.

10. The method for constructing a two-dimensional chiral nano superlattice according to claim 1, characterized in that: in, The hybridization temperature of hybridizing the DNA-modified nanoparticles or nanorods with the two-dimensional DNA origami array is lower than the melting temperature of the two-dimensional DNA array.

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