Preparation method, product and application of asymmetric polymer monolayer single-pore hollow nanoparticles

Abstract

The present application belongs to the field of new nanomaterial technology, and particularly relates to a preparation method, product and application of asymmetric polymer monolayer single-pore hollow nanoparticles. The preparation method of the present application comprises: preparing hydrophilic core / hydrophobic shell nanoparticles, and soaking the hydrophilic core / hydrophobic shell nanoparticles in a selected solvent for swelling and explosion, and then dispersing the asymmetric single-pore nanoparticles obtained by swelling and explosion in water and letting them stand, thereby obtaining asymmetric polymer monolayer single-pore hollow nanoparticles. The preparation method of the present application can prepare asymmetric polymer monolayer single-pore hollow nanoparticles with controllable opening size, uniform particle size and high yield, thereby successfully filling the technical gap in the controllable preparation of asymmetric polymer monolayer single-pore hollow nanoparticles, and the preparation process of the present application is simple and easy to control, the prepared product has good structural consistency, and the single pore size can be adjusted in a wide range.

Description

Technical Field

[0001] The present application belongs to the field of nanomaterial technology, and particularly relates to a preparation method, product and application of asymmetric polymer monolayer single-pore hollow nanoparticles. Background Art

[0002] Asymmetric polymer monolayer single-pore hollow nanoparticles are nanoparticles with a single-molecule layer asymmetric structure and a large opening (pore diameter ≥ 10nm). This unique large-pore asymmetric monolayer structure not only makes it easier to load and controllably release drug molecules in the biopharmaceutical field, but also has broad application prospects in interfacial stabilization and interfacial catalysis. Therefore, the controllable preparation of asymmetric polymer monolayer single-pore hollow nanoparticles has attracted much attention.

[0003] Currently, related technologies have demonstrated the ability to prepare asymmetric monolayer assemblies through three-dimensional soft confined self-assembly and disassembly, successfully achieving the efficient preparation of a variety of Janus nanoparticles in the form of discs, rings, dumbbells, and cups. For example, Deng Renhua et al. first fabricated strawberry-shaped patch spheres through three-dimensional confined assembly of diblock copolymers. After cross-linking the surface patch protrusions, they disassembled the continuous phase to produce Janus nanoparticles.

[0004] However, there has been no breakthrough in the controllable preparation of the highly-anticipated asymmetric polymer monolayer single-pore hollow nanoparticles, which greatly limits their application and development in efficient drug loading and controlled release, as well as the controllable movement of micro-nanomotors. Therefore, there is an urgent need to develop simple, efficient and controllable preparation methods to fill this technological gap. Summary of the Invention

[0005] This application aims to solve the technical gap in the controllable preparation of asymmetric polymer monolayer single-pore hollow nanoparticles by disclosing a preparation method, product and application of asymmetric polymer monolayer single-pore hollow nanoparticles.

[0006] In order to achieve the above objectives, the technical solutions adopted in this application are:

[0007] The first aspect of the present application provides a method for preparing asymmetric polymer monolayer single-pore hollow nanoparticles, the preparation method comprising the steps of:

[0008] The amphiphilic diblock polymer is prepared into hydrophilic core / hydrophobic shell nanoparticles through an emulsification-solvent evaporation method;

[0009] soaking the hydrophilic core / hydrophobic shell nanoparticles in a selected solvent to swell and explode, and separating and collecting asymmetric single-porous nanoparticles;

[0010] dispersing the asymmetric single-porous nanoparticles in water and allowing the asymmetric polymer monolayer single-porous hollow nanoparticles to stand, and separating and collecting the asymmetric polymer monolayer single-porous hollow nanoparticles;

[0011] The selected solvent can penetrate the hydrophobic shell and be absorbed and swelled by the hydrophilic core.

[0012] In a preferred embodiment, the amphiphilic diblock copolymer comprises polystyrene-poly(4-vinylpyridine).

[0013] In a preferred embodiment, the selected solvent comprises an ethanol aqueous solution having a volume concentration greater than or equal to 40%.

[0014] In a preferred embodiment, the molecular weight ratio of the hydrophobic segment to the hydrophilic segment in the amphiphilic diblock copolymer molecular chain is 0.9-2.0.

[0015] In a preferred embodiment, when the hydrophilic core / hydrophobic shell nanoparticles are immersed in a selected solvent to swell and explode, the system temperature is 25-60° C. and the time is greater than or equal to 1 hour.

[0016] The second aspect of the present application provides asymmetric polymer monolayer single-pore hollow nanoparticles prepared by the preparation method of the present application. The asymmetric polymer monolayer single-pore hollow nanoparticles have a hollow-shell structure;

[0017] The shell layer comprises a chemically bonded hydrophilic inner shell layer and an oleophilic outer shell layer, wherein the chemically bonded hydrophilic inner shell layer and the oleophilic outer shell layer are composed of an amphiphilic diblock polymer self-assembled monolayer structure;

[0018] The shell contains a nanopore that passes through the shell.

[0019] In a preferred embodiment, the particle size of the nanoparticles is 30-200 nm, the shell thickness is 10-80 nm, and the pore size of the nanopores is 10-120 nm; and

[0020] The ratio of the particle size to the shell thickness is greater than 2; the ratio of the particle size to the pore size is greater than or equal to 1.

[0021] The third aspect of the present application provides the use of the asymmetric polymer monolayer single-pore hollow nanoparticles of the present application in the preparation of functionalized single-pore hollow composite nanoparticles.

[0022] The fourth aspect of the present application provides a functionalized single-pore hollow composite nanoparticle, which comprises the asymmetric polymer monolayer single-pore hollow nanoparticle of the present application and a functionalized inorganic material; wherein the functionalized inorganic material is loaded on the inner wall of the hydrophilic inner shell layer of the asymmetric polymer monolayer single-pore hollow nanoparticle.

[0023] The fourth aspect of the present application provides a method for preparing the functionalized single-pore hollow composite nanoparticles of the present application, the preparation method comprising the steps of:

[0024] preparing an aqueous dispersion of the asymmetric polymer monolayer single-pore hollow nanoparticles;

[0025] After mixing and reacting the aqueous dispersion of the asymmetric polymer monolayer single-pore hollow nanoparticles with the aqueous solution of the functionalized inorganic material precursor, separating and collecting the precipitate A;

[0026] The precipitate A is dispersed in water and a reducing agent is added for reaction, and then the precipitate B is separated and collected, and the precipitate B is dispersed in water to obtain functionalized single-pore hollow composite nanoparticles.

[0027] Compared with the prior art, the advantages or beneficial effects of the embodiments of the present application include at least:

[0028] The preparation method provided by the present application is to prepare hydrophilic core-hydrophobic shell nanoparticles by emulsification-solvent volatilization using amphiphilic diblock copolymers as raw materials, and then disperse the nanoparticles in a selective swelling solvent of the core hydrophilic segment and in water for immersion, thereby preparing asymmetric polymer monolayer single-pore hollow nanoparticles with controllable opening size, uniform particle size and high yield, thereby successfully filling the technical gap in the controllable preparation of asymmetric polymer monolayer single-pore hollow nanoparticles, and the preparation process is simple and easy to control. The prepared product has good structural consistency and a wide range of adjustable single-pore size. More importantly, compared with existing single-pore hollow nanoparticles, the shell layer of the asymmetric polymer monolayer single-pore hollow nanoparticles prepared in the present application is a block copolymer monolayer structure, specifically an asymmetric structure of a hydrophilic inner shell layer-lipophilic outer shell layer. Thanks to this unique single-pore asymmetric structure, the asymmetric polymer monolayer single-pore hollow nanoparticles have better functional design potential. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] To more clearly illustrate the technical solutions of the embodiments of this application, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some of the embodiments described in this application. For those skilled in the art, other drawings can be derived from these drawings without inventive effort.

[0030] Figure 1 PS provided in the embodiment of this application 110k -P4VP 107k NPs and PS 110k -P4VP 107k TEM images of BPNPs;

[0031] Figure 2 PS provided in the embodiment of this application 110k -P4VP 107k NPs and PS 110k -P4VP 107k Statistical distribution of particle size of BPNPs;

[0032] Figure 3 PS under different preparation conditions provided in the examples of this application 110k -P4VP 107k TEM images of BPNPs;

[0033] Figure 4 PS provided in the embodiment of this application 110k -P4VP 107k TEM image of BPNPs@Pt;

[0034] Figure 5 PS provided in the embodiment of this application 110k -P4VP 107k Test results of the motility of BPNPs@Pt as nanomotors. DETAILED DESCRIPTION

[0035] The following will be combined with the accompanying drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0036] In the following description, the term "and / or" is used to describe the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A exists alone, B exists alone, and A and B exist simultaneously. A and B can be singular or plural; the single symbol " / " means "or".

[0037] In the following description, the term "at least one" means one or more, and "plurality" means two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, "at least one of A, B or C", or "at least one of A, B and C" can mean any one of A, B, C, or A+B, or A+C, or B+C, or A+B+C, where A, B, and C can be single or multiple.

[0038] In the following description, the order of serial numbers does not mean the order of execution. Some or all steps can be executed in parallel or sequentially. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of this embodiment.

[0039] In the following description, numerical ranges should be understood to also specifically disclose every intervening value between the upper and lower limits of the range. Each smaller range between any stated value or intervening value in a stated range and any other stated value or intervening value in the stated range is also included in the present embodiment, and the upper and lower limits of the smaller ranges may independently be included or excluded in the range.

[0040] Unless otherwise indicated, the technical / scientific terms used in this application have the same meanings as those generally understood by those skilled in the art. Although this application describes only preferred methods and materials, any similar or equivalent methods and materials may also be used in the implementation or testing of this application. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials related to the documents. In the event of any conflict with any incorporated document, the content of this specification shall prevail.

[0041] In a first aspect, the present invention provides a method for preparing asymmetric polymer monolayer single-pore hollow nanoparticles, the method preferably comprising:

[0042] S1: preparing amphiphilic diblock polymers into hydrophilic core / hydrophobic shell nanoparticles through an emulsification-solvent evaporation method;

[0043] S2: soaking the hydrophilic core / hydrophobic shell nanoparticles in a selected solvent to swell and explode, and separating and collecting asymmetric single-porous nanoparticles;

[0044] S3: dispersing the asymmetric single-porous nanoparticles in water and allowing the water to stand, and separating and collecting the asymmetric polymer monolayer single-porous hollow nanoparticles;

[0045] The selected solvent can penetrate the hydrophobic shell and be absorbed and swelled by the hydrophilic core.

[0046] It should be noted that the present embodiment of the present application does not specifically limit the specific process of preparing hydrophilic core / hydrophobic shell nanoparticles from amphiphilic diblock polymers through the emulsification-solvent evaporation method, as well as the materials, reagents, and process parameters used, so long as the hydrophilic core / hydrophobic shell nanoparticles can be prepared. Among them, the present embodiment of the present application exemplifies a preferred method for preparing hydrophilic core / hydrophobic shell nanoparticles from amphiphilic diblock copolymers, which specifically includes:

[0047] The amphiphilic diblock copolymer is fully dissolved in a selected organic solvent having hydrophobic segments that are incompatible with water, and the formed amphiphilic diblock copolymer solution is an oil phase;

[0048] preparing an aqueous solution containing a surfactant as the aqueous phase;

[0049] The oil phase and the aqueous phase are mixed and emulsified, and the emulsion is placed in a constant temperature chamber at 30°C for 24 hours. After the selected organic solvent is completely volatilized, the remaining solution is centrifuged, the supernatant is removed, and an appropriate amount of deionized water is added to the precipitate for ultrasonic dispersion to obtain hydrophilic core / hydrophobic shell nanoparticles. The specific process of the emulsification is as follows:

[0050] After the oil phase and the water phase are mixed, they are passed through a membrane emulsification device at a uniform speed for several times to obtain an oil / water emulsion, and the oil / water emulsion is exposed to evaporate for 24 hours to allow the selected organic solvent to evaporate completely. The pore size of the filter membrane of the membrane emulsification device can be 0.45μm, 0.20μm or 1.0μm; the number of membrane passes is 10-40 times. The embodiment of the present application does not limit the specific structure and model of the membrane emulsification device, and it can be various membrane emulsification equipment commonly used in the field, as long as it can achieve emulsification.

[0051] It should be understood by those skilled in the art that the main purpose of adding an appropriate amount of deionized water to the precipitate for ultrasonic dispersion is to further wash away the selected organic solvent, so the relevant ultrasonic dispersion operation is preferably performed three times, and an operation of centrifugal separation of the precipitate is also included after each ultrasonic dispersion.

[0052] Of course, the preferred method described above in this specification does not represent a specific limitation on the preparation process related to this application. Therefore, when performing the preparation process related to the embodiments of this application, if there is a preparation process different from that described in this specification, it also falls within the scope of protection of this application.

[0053] It should be noted that the embodiments of the present application have no special restrictions on the specific material composition of the solvent, so long as it can penetrate the hydrophobic shell of the hydrophilic core / hydrophobic shell nanoparticles and be absorbed and swollen by the hydrophilic core. Those skilled in the art can make a reasonable choice based on the properties of the segments contained in the amphiphilic diblock copolymer. At the same time, the embodiments of the present application have no special restrictions on the separation means for separating and collecting single-porous nanoparticles, so long as it can separate single-porous nanoparticles from the dispersion system. For example, the embodiments of the present application are centrifuged at a high speed of 15,000 r / min for 20 minutes.

[0054] Based on the above description, the embodiment of the present application uses an amphiphilic diblock copolymer as a raw material to prepare hydrophilic core-hydrophobic shell nanoparticles through emulsification-solvent evaporation, and then disperses the nanoparticles in a selective swelling solvent of the core hydrophilic segment and in water for immersion, thereby preparing asymmetric polymer monolayer single-pore hollow nanoparticles with controllable opening size, uniform particle size, and high yield, thereby successfully filling the technical gap of the controllable preparation of asymmetric polymer monolayer single-pore hollow nanoparticles, and the preparation process is simple and easy to control. The prepared product has good structural consistency and a wide range of adjustable single-pore size. More importantly, compared with existing single-pore hollow nanoparticles, the shell layer of the asymmetric polymer monolayer single-pore hollow nanoparticles prepared in this application is a block copolymer monolayer structure, specifically an asymmetric structure of a hydrophilic inner shell layer-lipophilic outer shell layer. Thanks to this unique single-pore asymmetric structure, the asymmetric polymer monolayer single-pore hollow nanoparticles have better functional design potential.

[0055] In a preferred embodiment, the amphiphilic diblock copolymer is preferably polystyrene-poly(4-vinylpyridine) (PS-b-P4VP). When hydrophilic core / hydrophobic shell nanoparticles are prepared using polystyrene-poly(4-vinylpyridine) as a raw material via an emulsification-solvent evaporation method, the organic solvent selected for preparing the oil phase is toluene, tetrahydrofuran, or the like, which is not particularly limited in this embodiment of the present application; the concentration of the polystyrene-poly(4-vinylpyridine) solution is 0.5-10.0 mg / mL; and the surfactant used to prepare the aqueous phase is cetyltrimethylammonium bromide (CTAB), and the concentration of the surfactant aqueous solution is 0.5-5.0 mg / mL.

[0056] In a preferred embodiment, the selected solvent comprises an ethanol aqueous solution with a volume concentration greater than or equal to 40%, for example, 40% ethanol aqueous solution, 60% ethanol aqueous solution, 80% ethanol aqueous solution, anhydrous ethanol or any ethanol aqueous solution within the volume concentration range.

[0057] It should be noted that the embodiments of the present application can adjust the single pore size of the prepared asymmetric polymer monolayer single-pore hollow nanoparticles by controlling the selected solvent and volume concentration, thereby obtaining asymmetric structure nanoparticles with large-sized (pore size ≥ 10 nm) openings, which is conducive to the encapsulation and controlled release of drug molecules.

[0058] In a preferred embodiment, the molecular weight ratio of the hydrophobic segment to the hydrophilic segment in the amphiphilic diblock copolymer molecular chain is 0.9-2.0, specifically the molecular weight ratio of the polystyrene segment to the poly(4-vinylpyridine) segment in the polystyrene-poly(4-vinylpyridine) is 0.9-2.0, preferably 0.9, 0.95, 0.98, 1.18, 1.25, 1.5, 1.8, 2.0 or any one within the range. Wherein, the molecular weight of the polystyrene segment in the polystyrene-poly(4-vinylpyridine) molecular chain is 9000-200000, and the molecular weight of the poly(4-vinylpyridine) segment is 10000-110000, which can be exemplified by PS 9.8k -P4VP 10k 、PS 20k -P4VP 17k 、PS 110k -P4VP 107k、 PS 122k -P4VP 75k 、PS 188k -P4VP 96k wait.

[0059] It should be noted that, in the embodiment of the present application, by controlling the molecular weight ratio, the particle size of the prepared asymmetric polymer monolayer single-pore hollow nanoparticles can be regulated, thereby preparing asymmetric polymer monolayer single-pore hollow nanoparticles with controllable particle size, which is conducive to meeting different application requirements.

[0060] In a preferred embodiment, the hydrophilic core / hydrophobic shell nanoparticles are immersed in a selected solvent to swell and explode at a temperature of preferably 25-60°C for a time of 1 hour or longer. In this embodiment, by controlling the temperature parameter, the single pore diameter of the prepared asymmetric polymer monolayer single-pore hollow nanoparticles can be enhanced and adjusted in accordance with the selected solvent and volume concentration, resulting in asymmetric nanoparticles with large openings (pore diameter ≥ 10 nm), which facilitates the entrapment and controlled release of drug molecules.

[0061] In a second aspect, the present invention also provides an asymmetric polymer monolayer single-pore hollow nanoparticle prepared by the preparation method of the present invention, wherein the asymmetric polymer monolayer single-pore hollow nanoparticle has a hollow-shell structure;

[0062] The shell layer comprises a chemically bonded hydrophilic inner shell layer and an oleophilic outer shell layer, wherein the chemically bonded hydrophilic inner shell layer and the oleophilic outer shell layer are composed of an amphiphilic diblock polymer self-assembled monolayer structure;

[0063] The shell contains a nanopore that passes through the shell.

[0064] The asymmetric polymer monolayer single-pore hollow nanoparticles provided in the embodiments of the present application have an asymmetric structure of a hydrophilic inner shell and a lipophilic outer shell, wherein the inner wall of the hydrophilic inner shell can provide more active sites, making it easier to load functionalized inorganic materials. Combined with the large-size opening, it can exhibit unique advantages in terms of efficient loading and controlled release of drug molecules, controllable movement of micro-nano motors, etc.; the lipophilic outer shell enables it to be used in the field of oil-water separation, effectively expanding its application range, and can maintain a stable structure in the solution for a long time; at the same time, the particle size is controllable and the distribution is relatively uniform, with a single pore with adjustable pore size, and the nanoparticle shell thickness is moderate.

[0065] In a preferred embodiment, the particle size of the asymmetric polymer monolayer single-pore hollow nanoparticles is 30-200 nm, preferably 80-150 nm, the shell thickness is 10-80 nm, and the pore size of the nanopore is 10-120 nm, preferably 20-50 nm; and the ratio of the particle size to the shell thickness is greater than 2; the ratio of the particle size to the pore size is greater than or equal to 1.

[0066] It should be noted that the embodiments of the present application, by adjusting and controlling the above-mentioned size parameters, can not only effectively enhance its application potential in the loading and controlled release of drug molecules and the controllable movement of micro-nanomotors, but also effectively ensure long-term stability in solution.

[0067] Thirdly, the present invention provides examples of the application of the asymmetric polymer monolayer single-hole hollow nanoparticles of the present invention in functionalized single-hole hollow composite nanoparticles. The unique large-sized openings and asymmetric structure of a hydrophilic inner shell and an oleophilic outer shell of the asymmetric polymer monolayer single-hole hollow nanoparticles of the present invention facilitate the efficient loading of functional inorganic materials and increase the loading capacity, while also making the functionalized composite nanoparticles highly designable and facilitating the long-term stability of the composite nanoparticles in solution. Furthermore, the preparation method of the present invention is simple, has a high yield, and is well controllable, making it advantageous for commercialization.

[0068] Fourthly, embodiments of the present application further provide a functionalized single-pore hollow composite nanoparticle. The functionalized single-pore hollow composite nanoparticle of the embodiment of the present application comprises the asymmetric polymer monolayer single-pore hollow nanoparticle described herein; and a functionalized inorganic material loaded on the inner wall of the hydrophilic inner shell of the asymmetric polymer monolayer single-pore hollow nanoparticle. The functionalized inorganic material refers to an inorganic material with a specific function, such as an inorganic material used in drug delivery, oil-water separation, nanomotors, nanoreactors, and the like, preferably gold, platinum, iron, or the like.

[0069] In a fifth aspect, the embodiments of the present application further provide a method for preparing the functionalized single-pore hollow composite nanoparticles described in the present application, preferably comprising:

[0070] preparing an aqueous dispersion of the asymmetric polymer monolayer single-pore hollow nanoparticles;

[0071] After mixing and reacting the aqueous dispersion of the asymmetric polymer monolayer single-pore hollow nanoparticles with the aqueous solution of the functionalized inorganic material precursor, separating and collecting the precipitate A;

[0072] The precipitate A is dispersed in water and a reducing agent is added for reaction, and then the precipitate B is separated and collected, and the precipitate B is dispersed in water to obtain functionalized single-pore hollow composite nanoparticles.

[0073] It should be noted that the present examples do not specify the mass concentrations of the aqueous dispersion and the functionalized inorganic material precursor aqueous solution, nor their volume ratios, which can be adjusted appropriately based on the loading requirements. Furthermore, the present examples do not specify the type of reducing agent or the specific parameters of each reaction step, which are determined to meet the corresponding reaction requirements. Functionalized inorganic material precursors include, but are not limited to, HAuCl₄ and K₂PtCl₄.

[0074] The technical solution of the present application will be further described below in conjunction with specific embodiments.

[0075] Example 1

[0076] This embodiment provides an asymmetric polymer monolayer single-hole hollow nanoparticle (PS 110k -P4VP 107k The preparation method of BPNPs comprises the following steps:

[0077] S101: Prepare 1.0 mg / mL PS 110k -P4VP 107k After adding 100 μL of PS 110k -P4VP 107k / toluene solution and 1 mL of CTAB aqueous solution were mixed, and the resulting mixture was passed through a membrane emulsifier 20 times, and then placed in an open volatilization environment at 30°C for 24 hours. The volatilized solution was centrifuged at a speed of 15000 r / min for 20 minutes, the supernatant was removed, and the precipitate was collected and dispersed with water and centrifuged three times to remove CTAB. The collected precipitate was the core-shell structure nanoparticles (PS 110k -P4VP 107k NPs).

[0078] S102: To PS 110k -P4VP107k 1 mL of anhydrous ethanol was added to the NPs, ultrasonically dispersed and allowed to stand at room temperature for 2 h, then centrifuged at 15000 r / min for 20 min, the supernatant was removed, and the precipitate was collected to obtain asymmetric single-porous nanoparticles (PS 110k -P4VP 107k PNPs).

[0079] S103: To PS 110k -P4VP 107k Add 1 mL of deionized water to PNPs and disperse them by ultrasonication to obtain PS. 110k -P4VP 107k BPNPs.

[0080] Example 2

[0081] This embodiment provides an asymmetric polymer monolayer single-hole hollow nanoparticle (PS 110k -P4VP 107k The preparation method of BPNPs comprises the following steps:

[0082] S201: Prepare 1.0 mg / mL PS 110k -P4VP 107k After adding 100 μL of PS 110k -P4VP 107k / toluene solution and 1 mL of CTAB aqueous solution were mixed, and the resulting mixture was passed through a membrane emulsifier 20 times, and then placed in an open volatilization environment at 30°C for 24 hours. The volatilized solution was centrifuged at a speed of 15000 r / min for 20 minutes, the supernatant was removed, and the precipitate was collected and dispersed with water and centrifuged three times to remove CTAB. The collected precipitate was the core-shell structure nanoparticles (PS 110k -P4VP 107k NPs).

[0083] S202: To PS 110k -P4VP 107k 1 mL of 40% v / v ethanol aqueous solution was added to the NPs, ultrasonically dispersed, and allowed to stand in a water bath at 50°C for 1 h. The mixture was then centrifuged at 15,000 rpm for 20 min, the supernatant was removed, and the precipitate was collected to obtain the asymmetric single-porous nanoparticles (PS 110k -P4VP 107k PNPs).

[0084] S203: To PS 110k -P4VP 107k Add 1 mL of deionized water to PNPs and disperse them by ultrasonication to obtain PS. 110k -P4VP107k BPNPs.

[0085] Example 3

[0086] This embodiment provides an asymmetric polymer monolayer single-hole hollow nanoparticle (PS 122k -P4VP 75k The preparation method of BPNPs comprises the following steps:

[0087] S301: Prepare 1.0 mg / mL PS 122k -P4VP 75k / toluene solution and 1.0 mg / mL CTAB aqueous solution, 100 μL of PS 110k -P4VP 107k / toluene solution and 1 mL of CTAB aqueous solution were mixed, and the resulting mixture was passed through a membrane emulsifier 20 times, and then placed in an open volatilization environment at 30°C for 24 hours. The volatilized solution was centrifuged at a speed of 15000 r / min for 20 minutes, the supernatant was removed, and the precipitate was collected and dispersed with water and centrifuged three times to remove CTAB. The collected precipitate was the core-shell structure nanoparticles (PS 122k -P4VP 75k NPs).

[0088] S302: To PS 122k -P4VP 75k 1 mL of anhydrous ethanol was added to the NPs, ultrasonically dispersed, and placed in a 50°C water bath for 1 h. The mixture was then centrifuged at 15,000 rpm for 20 min, the supernatant was removed, and the precipitate was collected to obtain the asymmetric single-porous nanoparticles (PS 122k -P4VP 75k PNPs);

[0089] S303: To PS 122k -P4VP 75k Add 1 mL of deionized water to PNPs and disperse them by ultrasonication to obtain PS. 122k -P4VP 75k BPNPs.

[0090] Example 4

[0091] This embodiment provides an asymmetric polymer monolayer single-hole hollow nanoparticle (PS 188k -P4VP 96k The preparation method of BPNPs comprises the following steps:

[0092] S301: Prepare 1.0 mg / mL PS 188k -P4VP 96k / toluene solution and 1.0 mg / mL CTAB aqueous solution, 100 μL of PS 110k -P4VP 107k / toluene solution and 1 mL of CTAB aqueous solution were mixed, and the resulting mixture was passed through a membrane emulsifier 20 times, and then placed in an open volatilization environment at 30°C for 24 hours. The volatilized solution was centrifuged at a speed of 15000 r / min for 20 minutes, the supernatant was removed, and the precipitate was collected and dispersed with water and centrifuged three times to remove CTAB. The collected precipitate was the core-shell structure nanoparticles (PS 188k -P4VP 96k NPs).

[0093] S302: To PS 188k -P4VP 96k 1 mL of anhydrous ethanol was added to the NPs, ultrasonically dispersed, and allowed to stand in a 60°C water bath for 1 h. The mixture was then centrifuged at 15,000 rpm for 20 min, the supernatant was removed, and the precipitate was collected to obtain the asymmetric single-porous nanoparticles (PS 188k -P4VP 96k PNPs);

[0094] S303: To PS 188k -P4VP 96k Add 1 mL of deionized water to PNPs and disperse them by ultrasonication to obtain PS. 188k -P4VP 96k BPNPs.

[0095] To illustrate that the preparation method of this application successfully prepared asymmetric polymer monolayer single-pore hollow nanoparticles, this specification provides the following test examples:

[0096] 1. PS prepared in Example 1 110k -P4VP 107k NPs and PS 110k -P4VP 107k BPNPs were used as test samples for TEM characterization, and the results were Figure 1 As shown. Where a is PS 110k -P4VP 107k TEM image of NPs; b is PS 110k -P4VP 107k TEM image of BPNPs.

[0097] according to Figure 1 a It can be seen that the PS prepared in the embodiment of this application 110k -P4VP 107k NPs are nanoparticles with a core-shell structure, specifically with PS as the shell and P4VP as the core; Figure 1b It can be seen that the PS prepared in the embodiment of this application 110k -P4VP 107k BPNPs have an asymmetric single-pore structure, specifically with PS as the outer shell and P4VP as the inner shell, and a large-sized opening running through the PS outer layer and the P4VP inner shell.

[0098] Furthermore, for PS 110k -P4VP 107k NPs and PS 110k -P4VP 107k The particle size of BPNPs was statistically distributed, and the results were Figure 2 As shown. Among them, Figure 2 For PS 110k -P4VP 107k NPs and PS 110k -P4VP 107k Statistical distribution of particle size of BPNPs.

[0099] according to Figure 1-2 It can be seen that PS 110k -P4VP 107k The particle size of BPNPs is about 114 nm, the single pore size is about 35 nm, and the shell thickness is about 33 nm.

[0100] 2. Use PS 110k -P4VP 107k NPs were used as the initial material to investigate the effects of solvent selection and swelling temperature on the structural properties of the final product. Figure 3 As shown. Among them, Figure 3 PS prepared under different preparation conditions 110k -P4VP 107k TEM image of BPNPs.

[0101] according to Figure 3 It can be seen that when the solvent is an ethanol aqueous solution with a volume concentration greater than or equal to 40% v / v, PS 110k -P4VP 107k NPs can swell and explode at a temperature of 40-50℃ and form asymmetric single-pore hollow nanoparticles; when the solvent is anhydrous ethanol water, PS 110k -P4VP 107k NPs can only form asymmetric single-pore hollow nanoparticles at a temperature of 40-50 °C, but cannot form asymmetric single-pore hollow nanoparticles at a temperature of 60 °C. The reason may be that PS 110k -P4VP 107k NPs will disassemble into micelles under selective solvent swelling and high temperature treatment.

[0102] At the same time, the particle size, shell thickness and single pore diameter of the asymmetric single-hole hollow nanoparticles prepared under different preparation parameters were statistically analyzed, and the results are shown in Table 1.

[0103] Table 1: PS 110k -P4VP 107k Technical indicators of asymmetric single-pore hollow nanoparticles formed by NPs under different preparation parameters

[0104]

[0105] Example 5

[0106] This embodiment provides a functionalized single-hole hollow composite nanoparticle (PS 110k -P4VP 107k Preparation of BPNPs@Pt) includes the following steps:

[0107] S501: Prepare a 50 mg / mL K2PtCl4 aqueous solution and add the K2PtCl4 aqueous solution to the PS solution at a molar ratio of K2PtCl4 to 4VP of 1:1. 110k -P4VP 107k BPNPs, stirred at room temperature for 12 h;

[0108] S502: PS is centrifuged 110k -P4VP 107k BPNPs were redispersed in the same volume of water, centrifuged at 15000 r / min for 20 min, and ascorbic acid, a weak reducing agent, was added at a molar ratio of reducing agent to K2PtCl4 of 1:1, and stirred at room temperature for 12 h;

[0109] S503: Re-disperse the nanoparticles into the same volume of water by centrifugation again, with a centrifugal speed of 15000 r / min and a centrifugal time of 20 min, and ultrasonic dispersion to obtain PS. 110k -P4VP 107k BPNPs@Pt.

[0110] To illustrate that the preparation method of this application successfully prepared functionalized single-hole hollow composite nanoparticles, the PS prepared in Example 5 is used below. 110k -P4VP 107k TEM characterization of BPNPs@Pt showed Figure 4 As shown. Among them, Figure 4 For PS 110k -P4VP 107k TEM image of BPNPs@Pt.

[0111] according to Figure 4It can be seen that Pt nanoparticles are selectively and uniformly loaded on the inner wall of P4VP of single-pore hollow composite nanoparticles.

[0112] Example 6

[0113] This embodiment provides a functionalized single-hole hollow composite nanoparticle (PS 110k -P4VP 107k The specific steps for the application of nanomotors based on BPNPs@Pt are as follows:

[0114] Functionalized single-porous hollow composite nanoparticles (PS 110k -P4VP 107k BPNPs@Pt) were added into H2O2 aqueous solution with different concentrations, and the PS 110k -P4VP 107k The mobility of BPNPs@Pt as nanomotor was investigated, and the corresponding diffusion constant (D) was calculated based on the mean square displacement (MSD) versus time (Δt) curve. e ) and the speed of movement (v), the result is Figure 5 As shown. Where a is PS 110k -P4VP 107k The mean square displacement (MSD) of BPNPs@Pt under different H2O2 concentrations changes with time (Δt); b is the diffusion constant (D) under the corresponding conditions obtained by analyzing the curve in a. e ) and movement speed (v).

[0115] according to Figure 5 It can be seen that PS 110k -P4VP 107k When BPNPs@Pt moves in a certain concentration of H2O2 aqueous solution, its mean square displacement (MSD) and time (Δt) show a quadratic function relationship, which is consistent with the characteristics of the directional motion of nanomotors, and PS 110k -P4VP 107k The mobility of BPNPs@Pt increases with the increase of H2O2 concentration, which is shown in D e and v gradually increase with the increase of H2O2 concentration. The test results show that PS 110k -P4VP 107k BPNPs@Pt exhibits nanomotor properties with directional motion.

[0116] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

[0117] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit the present application. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments can still be modified, or some or all of the technical features therein can be replaced by equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the present application.

Claims

1. A method for preparing asymmetric polymer monolayer single-pore hollow nanoparticles, characterized in that: Include: preparing hydrophilic core / hydrophobic shell nanoparticles by an emulsification-solvent evaporation method using an amphiphilic diblock copolymer comprising polystyrene-poly(4-vinylpyridine), wherein the molecular weight ratio of the hydrophobic segment to the hydrophilic segment in the amphiphilic diblock copolymer molecular chain is 0.9-2.0; soaking the hydrophilic core / hydrophobic shell nanoparticles in a selected solvent to swell and explode, and separating and collecting asymmetric single-porous nanoparticles; dispersing the asymmetric single-porous nanoparticles in water and allowing the asymmetric polymer monolayer single-porous hollow nanoparticles to stand, and separating and collecting the asymmetric polymer monolayer single-porous hollow nanoparticles; The selected solvent can penetrate the hydrophobic shell and be absorbed and swelled by the hydrophilic core.

2. The preparation method according to claim 1, characterized in that The selected solvent comprises an ethanol aqueous solution with a volume concentration greater than or equal to 40%.

3. The preparation method according to claim 1, characterized in that When the hydrophilic core / hydrophobic shell nanoparticles are immersed in a selected solvent to swell and explode, the system temperature is 25-60° C. and the time is greater than or equal to 1 hour.

4. An asymmetric polymer monolayer single-pore hollow nanoparticle prepared according to the preparation method of any one of claims 1 to 3, characterized in that: Possessing a hollow-shell structure; The shell layer comprises a chemically bonded hydrophilic inner shell layer and an oleophilic outer shell layer, wherein the chemically bonded hydrophilic inner shell layer and the oleophilic outer shell layer are composed of an amphiphilic diblock polymer self-assembled monolayer structure; The shell contains a nanopore that passes through the shell.

5. The asymmetric polymer monolayer single-pore hollow nanoparticles according to claim 4, characterized in that: The nanoparticles have a particle size of 30-200 nm, a shell thickness of 10-80 nm, and a nanopore diameter of 10-120 nm; and The ratio of the particle size to the shell thickness is greater than 2; the ratio of the particle size to the pore size is greater than or equal to 1.

6. Use of the asymmetric polymer monolayer single-pore hollow nanoparticles according to claim 4 or 5 in the preparation of functionalized single-pore hollow composite nanoparticles.

7. A functionalized single-pore hollow composite nanoparticle, characterized in that: Comprising the asymmetric polymer monolayer single-pore hollow nanoparticles according to claim 4 or 5 and a functionalized inorganic material; The functionalized inorganic material is loaded on the inner wall of the hydrophilic inner shell layer of the asymmetric polymer monomolecular layer single-pore hollow nanoparticles.

8. The method for preparing functionalized single-pore hollow composite nanoparticles according to claim 7, characterized in that: Include: preparing an aqueous dispersion of the asymmetric polymer monolayer single-pore hollow nanoparticles; After mixing and reacting the aqueous dispersion of the asymmetric polymer monolayer single-pore hollow nanoparticles with the aqueous solution of the functionalized inorganic material precursor, separating and collecting the precipitate A; The precipitate A is dispersed in water and a reducing agent is added for reaction, and then the precipitate B is separated and collected, and the precipitate B is dispersed in water to obtain functionalized single-pore hollow composite nanoparticles.

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