A method for preparing a structure-controllable multilayer nanoparticle microarray

Abstract

The application provides a preparation method of a structure-controllable multilayer nanoparticle microarray, and belongs to the technical field of functional polymer materials. The application is based on ultraviolet-initiated surface atom transfer radical polymerization (ATRP) reaction to prepare a PGMA polymer brush on the surface of a base material, then a photoresist film is attached on the base material with the PGMA polymer brush, different digital gray scale images are loaded by using a DMD dynamic light projection system, and then a patterned film with different shapes is prepared. After development, a silicon dioxide nanoparticle (SiO2-NPs) suspension is added dropwise into the pores of the patterned film, the solvent is evaporated in a hot environment, and after demolding, a multilayer nanoparticle microarray is obtained. The application realizes controllable preparation of a high-precision multilayer nanoparticle microarray by combining a photoresist film with a unique light regulation system of a DMD.

Description

Technical Field

[0001] This invention relates to the field of functional polymer materials technology, and in particular to a method for preparing a multilayer nanoparticle microarray with controllable structure. Background Technology

[0002] While researchers have made groundbreaking progress in the field of nanotechnology, they have discovered that the arraying of nanoparticles also significantly influences many of the properties of nanomaterials. Nanoparticle arraying generally refers to the process by which nanoparticles, under equilibrium conditions, spontaneously form thermodynamically stable, structurally defined, and functionally specific aggregates through non-covalent bonding. Therefore, many application areas require large-area nanoparticle arrays. Precise control of nanoparticle arraying is crucial. While amplifying the advantages of nanoparticles, nanoparticle arraying also significantly promotes the development of high-performance, high-throughput analytical detection methods and sensors, leading to the deepening application of nanoparticle microarrays in biochips, sensors, drug delivery, and other fields.

[0003] Photolithography is a technique that uses photoresist to transfer patterns from a photomask onto a substrate material under illumination, and it has been widely used in recent years. Dynamic optical projection (DMD) technology mainly utilizes the unique digital maskless photoreaction platform of DMD combined with a photoresist film to prepare patterned thin films, thus possessing advantages such as rapid reaction, low cost, and simple process. Commonly used methods for nanoparticle array formation include spin coating, external force method, vertical deposition method, and emulsion polymerization method. However, due to the complexity of these methods, uncontrollable structure, and inability to prepare nanoparticle microarrays with three-dimensional spatial structures, the application of nanoparticle microarrays in practical production and daily life is limited.

[0004] Digital micromirror devices (DMDs) offer significant advantages in projection, greatly facilitating the fabrication of patterned thin films and structurally controllable nanoparticle arrays. For example, researchers at the Hefei Institutes of Physical Science have constructed two-dimensional nanoparticle arrays with a "core-satellite" structure by altering the size, shape, and composition of the assembled particles and template particles. This resulted in two-dimensional binary nanoparticle arrays with rich structural diversity. The two-dimensional structures of the nanoparticle arrays prepared using this method are controllable and highly precise. However, the fabrication of multilayer nanoparticle arrays with three-dimensionally tunable structures using DMD photolithography combined with photoresist films remains a gap in research. Summary of the Invention

[0005] In view of this, the purpose of this invention is to provide a method for fabricating a multilayer nanoparticle microarray with controllable structure. This invention utilizes a DMD dynamic light projection system to fabricate patterned thin films with various shapes, and uses these patterned thin films as templates to fill the pores of the patterned thin films with nanoparticles, thereby achieving controllable fabrication of multilayer nanoparticle array structures of different shapes.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0007] This invention provides a method for preparing a structure-controllable multilayer nanoparticle microarray, comprising the following steps:

[0008] The matrix material is immersed in a dopamine solution to carry out a polymerization reaction, thereby obtaining a matrix material with a polydopamine (PDA) coating on the surface;

[0009] The material containing the PDA coating is immersed in an initiator solution to carry out a functionalization reaction, thereby obtaining a matrix material with surface initiator functionalization.

[0010] After coating the surface of the initiator-functionalized matrix material with a polymer reaction solution, a surface ATRP reaction is performed to obtain a matrix material containing a polymer brush. The ATRP reaction is controlled by ultraviolet light.

[0011] A photoresist film is laminated onto the surface of the substrate material containing the polymer brush, exposed, and developed to obtain a patterned thin film. The exposure process is controlled by a digital micromirror device.

[0012] A nanoparticle suspension is dropped into the pores of the patterned thin film, the solvent is evaporated at 35°C, and the photoresist film is demolded to obtain a multilayer nanoparticle microarray with controllable structure. The nanoparticles are silicon dioxide nanoparticles.

[0013] Preferably, the dopamine solution is dopamine hydrochloride / Tris-HCl buffer solution; the polymer reaction solution is glycidyl methacrylate / tris(2-phenylpyridine)iridium N,N-dimethylformamide solution.

[0014] Preferably, the concentration of dopamine hydrochloride in the dopamine hydrochloride / Tris-HCl buffer solution is 1 mg / mL.

[0015] Preferably, the molar concentration of glycidyl methacrylate in the N,N-dimethylformamide solution of glycidyl methacrylate / tris(2-phenylpyridine)iridium is 1.81 mol / L, and the molar concentration of tris(2-phenylpyridine)iridium is 1.52 mmol / L.

[0016] Preferably, the coating involves dropping the polymer reaction solution onto the surface of the initiator-functionalized matrix material, forming a uniform liquid film with a volume of 25 μL of polymer reaction solution.

[0017] Preferably, the initiator solution comprises anhydrous ethanol, Tris-HCl buffer, and 3-(trimethoxysilyl)propyl-2-bromo-2-methylpropionate.

[0018] Preferably, the volume ratio of the initiator solution to anhydrous ethanol / Tris-HCl buffer / 3-(trimethoxysilyl)propyl 2-bromo-2-methylpropionate is 2:1:1.

[0019] Preferably, the initiator functionalization reaction is carried out at a temperature of 50°C for 6 hours.

[0020] Preferably, the photoresist film is negative and has a thickness of 150 μm.

[0021] Preferably, the developing solution used in the developing process is purchased from Guangdong Taiyada Optoelectronics Co., Ltd.

[0022] Preferably, the release agent used in the demolding process is a 5% NaOH aqueous solution, and the demolding time is 10 minutes.

[0023] Preferably, the nanoparticles are silicon dioxide.

[0024] This invention provides a method for preparing a structure-controllable multilayer nanoparticle microarray, comprising the following steps:

[0025] A substrate material is immersed in a dopamine solution to perform a dopamine polymerization reaction, resulting in a substrate material with a polydopamine (PDA) coating. The PDA-coated substrate material is then immersed in an initiator solution for a functionalization reaction, resulting in an initiator-functionalized substrate material. After coating the initiator-functionalized substrate material with a polymer reaction solution, a surface ATRP reaction is performed to obtain a polymer-brush-containing substrate. The surface ATRP reaction is controlled by ultraviolet light. A photoresist film is then laminated onto the surface of the polymer-brush-containing substrate, and it is exposed under a DMD for 2 minutes. Subsequently, it is developed in a developer for 10 minutes, rinsed with deionized water, and dried under a nitrogen stream to obtain a patterned film. A silica nanoparticle suspension is added dropwise into the pores of the patterned film at a volume of 2 μL. The patterned film containing the silica nanoparticle suspension is placed on a heating stage to evaporate the solvent at a temperature of 35°C. The patterned film is then removed by placing it in a release agent for 10 minutes. Finally, the microarray was washed with deionized water and dried under a nitrogen flow to obtain the multilayer nanoparticle microarray with controllable structure, wherein the nanoparticles are silicon dioxide nanoparticles.

[0026] This invention discloses a method for fabricating a multilayer nanoparticle microarray with controllable structure based on patterned thin films. The method utilizes a digital micromirror device (DMD) to irradiate a substrate material surface to create a patterned thin film. A nanoparticle suspension is then added dropwise into the pores of the patterned thin film. After development and demolding, a multilayer nanoparticle microarray with controllable structure is obtained. First, a polymer is grafted onto the substrate material surface to create a pattern. Then, a photoresist film is laminated and exposed using a DMD. After exposure, the substrate material containing the photoresist film is developed in a developer to obtain a patterned thin film. A nanoparticle suspension is then added dropwise into the pores of the patterned thin film. After solvent evaporation and demolding, a multilayer nanoparticle microarray with controllable structure is obtained.

[0027] Compared with existing technologies, the present invention has the following advantages and beneficial effects:

[0028] (1) Unlike previous methods for preparing nanoparticle microarrays, the photoresist film used in this invention is low in cost, safe and non-toxic, and has a fast photoreaction speed. Using patterned thin films as templates, multilayer nanoparticle microarrays can be prepared quickly.

[0029] (2) The spatial structure of the multilayer nanoparticle microarray based on patterned thin film in this invention is tunable;

[0030] (3) The nanoparticle microarray obtained by the present invention is tightly arranged. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the method for preparing nanoparticle microarrays using a photoresist film combined with DMD dynamic light projection technology in Embodiment 1 of the present invention;

[0032] Figure 2 This is a flowchart illustrating the preparation of the polymer brush in Example 1 of the present invention;

[0033] Figure 3 These are optical microscope images of patterned thin films of different design sizes in Embodiment 1 of the present invention;

[0034] Figure 4 These are optical microscope images of patterned thin films with different design patterns in Example 1;

[0035] Figure 5 This is an optical microscope image of the nanoparticle microarray on the surface of the matrix material in Example 1;

[0036] Figure 6 The images are SEM images of the multilayer nanoparticle microarray based on patterned thin film fabrication and corresponding magnified SEM images of implementation 1. Detailed Implementation

[0037] This invention provides a method for preparing a structure-controllable nanoparticle microarray, comprising the following steps:

[0038] The matrix material is immersed in a dopamine solution to carry out a polymerization reaction, thereby obtaining a matrix material with a polydopamine (PDA) coating on the surface;

[0039] The material containing the PDA coating is immersed in an initiator solution to carry out a functionalization reaction, thereby obtaining a matrix material with surface initiator functionalization.

[0040] After coating the surface of the initiator-functionalized matrix material with a polymer reaction solution, a surface ATRP reaction is performed to obtain a matrix material containing a polymer brush. The ATRP reaction is controlled by ultraviolet light.

[0041] A photoresist film is laminated onto the surface of the substrate material containing the polymer brush, exposed, and developed to obtain a patterned thin film. The exposure process is controlled by a digital micromirror device.

[0042] A nanoparticle suspension is dropped into the pores of the patterned thin film, the solvent is evaporated under a thermal environment, and the photoresist film is removed to obtain a multilayer nanoparticle microarray with controllable structure. The nanoparticles are silicon dioxide nanoparticles.

[0043] Unless otherwise specified, all raw materials used in this invention are commercially available products in the field.

[0044] In this invention, the substrate material is preferably quartz glass or silicon wafer.

[0045] In this invention, the concentration of dopamine hydrochloride in the dopamine / Tris-HCl buffer solution is 2 mg / mL.

[0046] In this invention, the initiator solution preferably includes 3-(trimethoxysilyl)propyl 2-bromo-2-methylpropionate, anhydrous ethanol, and Tris-HCl buffer (pH=8.5), and the volume ratio of 3-(trimethoxysilyl)propyl 2-bromo-2-methylpropionate, anhydrous ethanol, and PBS buffer is preferably 1:2:1.

[0047] In this invention, the temperature of the functionalization reaction is preferably 50°C, and the time is preferably 6 hours.

[0048] In this invention, the photoresist film is negative and has a thickness of 150 μm.

[0049] In this invention, the developing solution used in the developing process was purchased from Guangdong Taiyada Optoelectronics Co., Ltd.

[0050] In this invention, the temperature of the evaporating solvent is 35°C.

[0051] In this invention, the release agent used in the demolding process is a 5% NaOH aqueous solution, and the demolding time is 10 minutes.

[0052] When the initiator solution is preferably a PDA / SiBr initiator solution, the preparation of the surface PDA coating preferably includes the following steps:

[0053] The substrate material was placed in a Tris-HCl buffer / dopamine hydrochloride solution and shaken to obtain a dopamine (PDA) coating, which was then ultrasonically cleaned and dried under nitrogen.

[0054] In this invention, the concentration of dopamine hydrochloride in the Tris-HCl buffer / dopamine hydrochloride solution is preferably 1 mg / mL.

[0055] In this invention, the operating temperature of the oscillation is preferably room temperature, and the operating time is preferably 40 minutes.

[0056] In this invention, the polymer reaction solution is preferably a solution of glycidyl methacrylate / tris(2-phenylpyridine)iridium N,N-dimethylformamide (GMA / Ir(ppy)3 / DMF).

[0057] In this invention, the molar concentration of glycidyl methacrylate in the N,N-dimethylformamide solution of glycidyl methacrylate / tris(2-phenylpyridine)iridium is preferably 1.81 mol / L, and the molar concentration of tris(2-phenylpyridine)iridium is preferably 1.52 mmol / L.

[0058] In this invention, the coating is preferably performed by dropping the polymer reaction solution onto the surface of the substrate material functionalized with the surface initiator, and covering it with a coverslip of volume 25 μL to form a uniform liquid film.

[0059] In this invention, the surface ATRP reaction is preferably carried out under DMD light irradiation conditions for a time of 10 min.

[0060] In this invention, the nanoparticles are silicon dioxide.

[0061] In this invention, the mass fraction of the nanoparticle solution is 1.25 wt%.

[0062] To further illustrate the present invention, the following detailed description, in conjunction with examples, of the structure-controllable multilayer nanoparticle microarrays, their preparation methods, and applications provided by the present invention, should not be construed as limiting the scope of protection of the present invention. Example 1

[0063] This embodiment describes a method for preparing a microarray of nanoparticles with controllable structure using a polydopamine (PDA) coating, comprising the following steps:

[0064] S1: Functionalization of silicon wafer surface initiators

[0065] (1) Place the silicon wafer in 1 mg / mL Tris-HCl buffer / dopamine hydrochloride solution (pH=8.5) and shake at a frequency of 500 rpm, at room temperature, for 40 min.

[0066] (2) Rinse the silicon wafer sequentially with deionized water, anhydrous ethanol, and deionized water for 3 minutes;

[0067] (3) After rinsing, the silicon wafer is dried under a nitrogen flow to obtain a silicon wafer with a PDA coating;

[0068] (4) Mix 3-(trimethoxysilyl)propyl 2-bromo-2-methylpropionate (SiBr), anhydrous ethanol and Tris-HCl buffer (pH=8.5) in a volume ratio of 1:2:1 to obtain an initiator solution.

[0069] (5) The silicon wafer was placed in the initiator solution and reacted at 50°C for 6 h to obtain a PDA / SiBr initiator composite coating.

[0070] S2: Preparation of PGMA polymer brush

[0071] (1) Prepare OEGMA / Ir(ppy)3 / DMF reaction solution with a monomer OEGMA molar concentration of 1.81 mol / L and a catalyst Ir(ppy)3 molar concentration of 1.52 mmol / L.

[0072] (2) Add 25 μL of reaction solution to the surface of the initiator-functionalized silicon wafer, cover it with a cover glass to form a uniform liquid film, and then place it under the DMD light modulation system for ATRP reaction for 10 min.

[0073] (3) After the reaction is complete, the silicon wafers are washed with anhydrous ethanol and deionized water in sequence, and dried under nitrogen flow to obtain PGMA-containing polymer brush wafers.

[0074] S3: Fabrication of patterned thin films on silicon wafer surfaces

[0075] (1) Place the silicon wafer containing the PGMA polymer brush on a heating table and heat it to 35°C. Then, attach the photoresist film to the silicon wafer.

[0076] (2) The silicon wafer with the photoresist film attached is placed under the DMD light projection system for exposure for 2 minutes.

[0077] (3) Place the exposed silicon wafer in the developer solution for development and rinse the silicon wafer with deionized water to obtain a patterned thin film on the surface of the silicon wafer. The development time is 10 min.

[0078] S4: Fabrication of silica nanoparticle microarrays

[0079] (1) Take 2 μL of silica nanoparticle suspension and add it to the pores of the patterned film. Evaporate the solvent in a thermal environment at a temperature of 35°C.

[0080] (2) Prepare a 5% NaOH aqueous solution as a release agent, place the patterned film containing the silica nanoparticle microarray in the release agent to demold, then rinse with deionized water and dry under nitrogen flow to obtain a multilayer silica nanoparticle microarray. The demolding time is 10 min.

[0081] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing a structure-controllable multilayer nanoparticle microarray, characterized in that, Includes the following steps: The matrix material is immersed in a dopamine solution to carry out a polymerization reaction, thereby obtaining a matrix material with a polydopamine (PDA) coating on the surface; The material containing the PDA coating is immersed in an initiator solution to carry out a functionalization reaction, thereby obtaining a matrix material with surface initiator functionalization. After coating the surface of the initiator-functionalized matrix material with a polymer reaction solution, a surface ATRP reaction is performed to obtain a matrix material containing a polymer brush. The ATRP reaction is controlled by ultraviolet light. A photoresist film is laminated onto the surface of the substrate material containing the polymer brush, exposed, and developed to obtain a patterned thin film. The exposure process is controlled by a digital micromirror device. A nanoparticle suspension is dropped into the pores of the patterned thin film, the solvent is evaporated at 35°C, and the photoresist film is demolded to obtain a multilayer nanoparticle microarray with controllable structure. The nanoparticles are silicon dioxide nanoparticles.

2. The preparation method according to claim 1, characterized in that, The dopamine solution is dopamine hydrochloride / Tris-HCl buffer solution; the polymer reaction solution is glycidyl methacrylate / tris(2-phenylpyridine)iridium N,N-dimethylformamide solution.

3. The preparation method according to claim 2, characterized in that, The concentration of dopamine hydrochloride in the dopamine / Tris-HCl buffer solution is 1 mg / mL.

4. The preparation method according to claim 2, characterized in that, The molar concentration of glycidyl methacrylate in the N,N-dimethylformamide solution of glycidyl methacrylate / tris(2-phenylpyridine)iridium is 1.81 mol / L, and the molar concentration of tris(2-phenylpyridine)iridium is 1.52 mmol / L.

5. The preparation method according to claim 1 or 2, characterized in that, The coating process involves dropping the polymer reaction solution onto the surface of the initiator-functionalized matrix material, forming a uniform liquid film with a volume of 25 μL of polymer reaction solution.

6. The preparation method according to claim 1, characterized in that, The initiator solution contains anhydrous ethanol, Tris-HCl buffer, and 3-(trimethoxysilyl)propyl-2-bromo-2-methylpropionate.

7. The preparation method according to claim 6, characterized in that, The initiator solution has an anhydrous ethanol / Tris-HCl buffer / 3-(trimethoxysilyl)propyl 2-bromo-2-methylpropionate volume ratio of 2:1:

1.

8. The preparation method according to claim 7, characterized in that, The initiator functionalization reaction was carried out at a temperature of 50°C for 6 hours.

9. The preparation method according to claim 1, characterized in that, The photoresist film is negative and has a thickness of 150 μm.

10. The preparation method according to claim 1, characterized in that, During the development and demolding processes, the developing solution was purchased from Guangdong Taiyada Optoelectronics Co., Ltd.; the demolding agent was a 5% NaOH aqueous solution, and the demolding time was 10 minutes.

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