Customizable and constructable MOF-based magnetic control micro-robot and preparation method and application thereof

Abstract

The invention discloses an MOF-based magnetic control micro-robot capable of being constructed in a customized mode and a preparation method and application of the MOF-based magnetic control micro-robot, and belongs to the technical field of micro-robots. The preparation method comprises the following steps that a micro-nano machining template method and a two-phase interface self-assembly method are coupled, and the magnetic MOF micro-robot is prepared; amino modification is conducted on the magnetic MOF micro-robot through a ligand exchange method, lipase is loaded through an ion adsorption method, and finally the MOF-based magnetic control micro-robot capable of being built in a customized mode is obtained. The micro-robot prepared by the preparation method disclosed by the invention can realize efficient driving under the action of a magnetic field, and can realize accurate control and execution of complex tasks; and meanwhile, the preparation method disclosed by the invention is simple and easy to implement, and is a preparation process of the customizable magnetic control MOF micro-robot capable of being prepared in a large scale.

Description

Technical Field

[0001] The present invention belongs to the technical field of microrobots, and in particular relates to a customizable MOF-based magnetically controlled microrobot and a preparation method and application thereof. Background Art

[0002] Microrobots are a type of micro-device that can convert external energy into its own kinetic energy, and they have shown great application potential in the fields of environmental remediation, biomedical engineering, and microfluidics. The energy sources for driving microrobots are diverse, including sound waves, light, electricity, heat, and magnetism. Among them, magnetically controlled microrobots have unique advantages in the biomedical field.

[0003] First, the excellent penetration ability of the magnetic field enables the microrobot to achieve precise manipulation without interfering with biological tissues. This non-invasive operation mode makes the magnetically controlled microrobot particularly effective in in vivo navigation and targeted drug delivery. For example, guided by an external magnetic field, the magnetically controlled microrobot can accurately reach the tumor area and achieve efficient local drug release, thereby reducing systemic side effects. In addition, the magnetically controlled microrobot has rapid response and high controllability. By adjusting the intensity and direction of the magnetic field, the movement path and speed of the microrobot can be controlled in real time, so that it can still maintain precise operation in a complex biological environment. At the same time, by selecting appropriate materials and surface modifications, the magnetically controlled microrobot can gradually degrade in the body, release harmless products, and avoid the potential risks of long-term retention. This feature ensures its safety in biomedical applications.

[0004] Metal-organic framework materials (MOFs) have shown great application potential in the biomedical field due to their unique structure and properties. MOFs are composed of metal ions or clusters connected to organic ligands through coordination bonds. They have highly ordered pores and extremely high specific surface area, and can efficiently load and release drug molecules. By adjusting the organic ligands and metal ions, the pore size and shape of MOFs can be precisely controlled, thereby achieving selective loading of different drug molecules. This adjustability provides the possibility for personalized treatment and improving drug bioavailability. MOFs also show excellent performance in terms of biocompatibility and degradability. Many MOF materials can gradually degrade under physiological conditions, releasing harmless decomposition products, avoiding the potential risks of long-term retention. In addition, through surface modification or functionalization, MOFs can further enhance their biocompatibility and impart specific biological functions, such as targeting and stimulus responsiveness. For example, magnetic MOFs can achieve targeted delivery under the guidance of an external magnetic field, while pH-responsive MOFs can quickly release drugs in the tumor microenvironment to improve the therapeutic effect.

[0005] Combining magnetically controlled microrobots with MOFs will produce unique advantages in the biomedical field. Magnetically controlled microrobots can achieve precise navigation and manipulation, while MOFs provide efficient drug loading and release capabilities. The combination of the two can achieve intelligent control and precise operation of drug delivery systems. For example, a magnetically controlled microrobot can carry a MOF structure and accurately reach the target area under the guidance of an external magnetic field, and achieve quantitative release of drugs through the pore structure of MOFs, thereby improving the therapeutic effect. In addition, the combination of magnetically controlled microrobots and MOFs can also achieve multifunctionality. For example, embedding magnetic nanoparticles in the MOF structure can achieve magnetically controlled navigation and drug delivery at the same time; or by functionalizing the MOF surface, targeted recognition and binding of specific biomolecules can be achieved. These multifunctional properties make the combination of magnetically controlled microrobots and MOFs have broad application prospects in the biomedical field.

[0006] However, although the combination of magnetically controlled microrobots and MOFs has shown great potential in the biomedical field, there are still some problems in current research. For example, the existing MOF microrobot structure lacks flexibility and is difficult to customize the required shape and function according to actual needs. This design limitation limits its application effect in complex biological environments. Summary of the invention

[0007] In view of the above technical problems, the present invention proposes a customizable MOF-based magnetically controlled microrobot and its preparation method and application. The microrobot prepared by the preparation method of the present invention can achieve efficient driving under the action of a magnetic field, and can achieve precise control and perform complex tasks; at the same time, the preparation method disclosed in the present invention is simple, and is a preparation process for a customizable magnetically controlled MOF microrobot that can be prepared in large quantities.

[0008] To achieve the above object, the present invention provides the following technical solutions:

[0009] One of the technical solutions of the present invention:

[0010] A method for preparing a customizable MOF-based magnetically controlled microrobot comprises the following steps:

[0011] The magnetic MOF microrobot was prepared by coupling the micro-nanofabrication template method with the two-phase interface self-assembly method.

[0012] The magnetic MOF microrobot is amino-modified by a ligand exchange method, and then lipase is loaded by an ion adsorption method, so as to finally obtain the customizable MOF-based magnetically controlled microrobot.

[0013] Preferably, the specific process of the micro-nano processing template method is:

[0014] After a sacrificial layer (Omnicot) is spin-coated on the silicon wafer, a photoresist is spin-coated after drying, and then dried. Then, a mask with a pattern is covered, and then exposure, drying, development and dipping are performed in sequence to obtain a SU-8 film with the desired pattern.

[0015] Further, the photoresist is SU-8 photoresist;

[0016] The developer used in the development process is PGMEA.

[0017] Furthermore, the thickness of the SU-8 film having the desired pattern is 20 μm.

[0018] Furthermore, the pattern includes any one of a spiral, an S-shape, a triangle, a quadrilateral, a circle, a multi-petal plum blossom, a sawtooth shape or a bowl shape.

[0019] Beneficial effects: The different shapes defined in the present invention correspond to different functions and applications. For example, spiral microrobots can be used for targeted drug delivery. Through the spiral design, they can move efficiently in body fluids and accurately reach the lesion area for treatment; bowl-shaped microrobots can be used for micro-operation and picking applications, such as manipulating and transporting objects in a microscopic environment; serrated microrobots can be used for cell manipulation and tissue engineering, and can perform cutting at specific locations to achieve cell fragmentation and thrombus removal, etc.; multi-petal plum blossom-shaped microrobots can be used for fluid dynamics research, and can efficiently push and stir in liquids, which helps mixing and reaction processes.

[0020] Preferably, the specific steps of the two-phase interface self-assembly method are:

[0021] Firstly, a metal salt solution is added into a container; then, a SU-8 film is placed therein; and finally, an octanol solution containing Fe3O4 and an organic ligand is added therein to carry out a self-assembly reaction.

[0022] Furthermore, the MOF constructed by the metal salt solution and the organic ligand includes any one of ZIF-8, HKUST-1, MOF-177, MOF-5, and MOF-74.

[0023] Further, the concentration of the metal salt solution is 0.17 mol / L; and / or

[0024] The content of Fe3O4 in the n-octanol solution is 800 mg / mL, and the concentration of the organic ligand is 0.08 mol / L.

[0025] Further, the metal salt solution is a zinc nitrate solution; and / or

[0026] The organic ligand is 2-methylimidazole.

[0027] Furthermore, the self-assembly reaction conditions are: reacting at room temperature for 120 minutes.

[0028] Preferably, the specific process of the ligand exchange method is:

[0029] The magnetic MOF microrobot was immersed in a 3-amino-1,2,4-triazole solution and reacted at 50° C. for 120 minutes.

[0030] Furthermore, the concentration of the 3-amino-1,2,4-triazole solution is 0.08 mol / L.

[0031] Preferably, the specific process of the ion adsorption method is:

[0032] The amino-modified magnetically controlled MOF microrobot was placed in a lipase solution and reacted for 12 hours.

[0033] Furthermore, the lipase solution is obtained by dissolving lipase in PBS, the lipase concentration is 2 mg / mL, and the PBS concentration is 10 mM.

[0034] The second technical solution of the present invention:

[0035] A customizable MOF-based magnetically controlled microrobot is prepared by the above preparation method.

[0036] The third technical solution of the present invention:

[0037] A method for manipulating a customizable MOF-based magnetically controlled microrobot comprises the following steps:

[0038] Under the condition of applying an external magnetic field, controlling the movement of the MOF-based magnetically controlled microrobot by a handle;

[0039] The external magnetic field conditions include any one of a constant field (1-10 mT, 0.1-35 Hz), an XY plane rotating field (5-10 mT, 8-15 Hz) or an XZ plane rotating field (3-10 mT, 1-6 Hz).

[0040] Preferably, the MOF-based magnetically controlled microrobot with a spiral shape can move efficiently and reach a designated target position under the condition of an external XZ plane rotating field (3-10 mT, 1-6 Hz).

[0041] Preferably, the bowl-shaped MOF-based magnetically controlled microrobot can move to a target position and pick up a target object under the combined control of an external XY plane rotating field (5-8 mT, 8-15 Hz) and a handle, thereby realizing the picking up and transportation of goods.

[0042] Preferably, the MOF-based magnetically controlled microrobot with a sawtooth shape can achieve high-speed rotational motion and cut target cells or tissues under the combined control of an external XY plane rotation field (8-10 mT, 8-10 Hz) and a handle.

[0043] Preferably, the MOF-based magnetically controlled microrobot with a multi-petal plum blossom shape can efficiently move and stir in a liquid under an external magnetic field (1-10 mT, 0.1-35 Hz).

[0044] The fourth technical solution of the present invention:

[0045] A customizable MOF-based magnetically controlled microrobot is used in the fields of triglyceride degradation, targeted drug delivery or thrombolytic therapy, wherein the drug loading rate of MOF-loaded DOX is as high as 68.43%, and it can target breast cancer. In addition, the loaded drug can also be t-PA with thrombolytic properties.

[0046] Preferably, the degradation process of triglycerides is:

[0047] In an acidic microenvironment, the MOF is decomposed by acid, thereby releasing the lipase for degrading triglycerides.

[0048] Compared with the prior art, the present invention has the following advantages and technical effects:

[0049] 1. The present invention realizes a microrobot with a designable structure by coupling the mature interfacial diffusion self-assembly strategy in the synthesis of metal organic framework materials with the micro-nano processing template method. This method makes it possible to design a variety of structures and can flexibly meet different application requirements. In addition, magnetic nanoparticles and drugs or enzymes can be loaded in an integrated manner, thereby effectively utilizing the pore structure of MOF materials and simplifying the synthesis process. This lays a solid foundation for subsequent magnetic manipulation and drug treatment.

[0050] 2. The present invention can achieve targeted precision control by optimizing magnetic field parameters, and can further improve the degradation efficiency caused by diffusion by combining different cutting motion forms. In addition, the release of responsive drugs or enzymes will further enhance the therapeutic effect. Combining these characteristics of microrobots with image-guided control technology will greatly expand its application in the biomedical field and provide an effective strategy for precision medicine. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0052] Figure 1A roadmap for preparing customizable SU-8 membranes and synthesizing MOF magnetically controlled microrobots through two-phase interface self-assembly for the present invention;

[0053] Figure 2 Optical microscope image of the customizable magnetically controlled MOF microrobot prepared in Example 2;

[0054] Figure 3 SEM and EDX images of the customizable magnetically controlled MOF microrobot prepared in Example 2;

[0055] Figure 4 Optical microscope images of MOF microrobots of different shapes prepared in Example 4;

[0056] Figure 5 This is a graph showing the relationship between the thickness of the MOF microrobot without magnetic material prepared in Example 3 and time;

[0057] Figure 6 The relationship between the speed and magnetic field frequency of the customizable magnetically controlled MOF microrobot prepared in Example 6;

[0058] Figure 7 The motion behavior diagram of the customizable magnetically controlled MOF microrobot prepared in Example 6 under the action of a constant magnetic field;

[0059] Figure 8 The repetitive motion trajectory diagram of the customizable magnetically controlled MOF microrobot prepared in Example 6 under the action of a rotating magnetic field in the YZ plane;

[0060] Fig. 9 This is a diagram of the customizable magnetically controlled MOF microrobot degrading triglycerides under different conditions in Example 8.

[0061] Fig.10 for Fig. 9 Figure 3. The decomposition of MOF and the release of lipase during the degradation of triglyceride by the customizable magnetically controlled MOF microrobot under the experimental conditions of Group C. DETAILED DESCRIPTION

[0062] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but should be understood as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0063] It should be understood that the terms described in the present invention are only for describing special embodiments and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. Each smaller range between the intermediate value in any stated value or stated range and any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0064] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0065] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to those skilled in the art. The present invention description and examples are exemplary only.

[0066] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0067] In the first aspect, the present invention discloses a method for preparing a customizable MOF-based magnetically controlled microrobot, comprising the following steps: first preparing a SU-8 film of a desired pattern, then synthesizing a magnetic MOF microrobot by a two-phase interface self-assembly method, and then combining lipase after amino modification to obtain a functional magnetic MOF microrobot;

[0068] The preparation process of the SU-8 film with the desired pattern is as follows:

[0069] A sacrificial layer (Omnicoat) is spin-coated on a clean silicon wafer, followed by a photolithography step, and finally the silicon wafer with the desired pattern is placed in N-methylpyrrolidone to remove the Omnicoat, thus obtaining a SU-8 film.

[0070] In some preferred embodiments, the SU-8 film can have any shape.

[0071] In some preferred embodiments, the thickness of the SU-8 film is about 20 μm.

[0072] In some preferred embodiments, the method for self-assembly of the two-phase interface is: firstly add an aqueous solution of zinc nitrate into a container, then put in a SU-8 film containing a desired pattern, and finally add an octanol solution containing Fe3O4 and 2-methylimidazole.

[0073] In some preferred embodiments, the reaction time of the two-phase interface self-assembly is 120 min.

[0074] In some preferred embodiments, the amino modification process is: placing the magnetic MOF microrobot into a 3-amino-1,2,4-triazole solution and reacting for 120 minutes.

[0075] In some preferred embodiments, the process of loading lipase is: adding the amino-modified magnetic MOF microrobot into the lipase solution and reacting for 12 hours.

[0076] In a second aspect, the present invention discloses a process of releasing lipase from a lipase-loaded MOF magnetically controlled microrobot, comprising: decomposing MOF (ZIF-8) with acid in an acidic microenvironment, thereby releasing lipase.

[0077] In a third aspect, the present invention provides a customizable functional MOF magnetically controlled microrobot prepared according to the above preparation method.

[0078] In a fourth aspect, the present invention provides an application of a MOF-based magnetically controlled microrobot in the fields of triglyceride degradation, targeted drug delivery, and thrombolytic therapy, specifically by using the MOF-based magnetically controlled microrobot under the action of a magnetic field to achieve precise navigation and manipulation.

[0079] The "room temperature" in the present invention refers to 20-30°C unless otherwise specified.

[0080] The raw materials used in the present invention are all purchased from the market.

[0081] The technical solution of the present invention is further illustrated by the following embodiments.

[0082] Example 1

[0083] The preparation of customizable SU-8 membranes includes the following steps:

[0084] (1) Cleaning the silicon wafer: The cleaning solution is a mixture of 30% hydrogen peroxide and 98% concentrated sulfuric acid in a volume ratio of 1:7; then, the silicon wafer is immersed in the cleaning solution and heated to 180°C for cleaning; after cleaning, the silicon wafer is alternately cleaned with water, isopropanol and acetone to ensure that its surface is thoroughly cleaned, and then a sacrificial layer (Omnicot) is spin-coated thereon;

[0085] (2) Preparing a SU-8 film with a five-petal plum blossom pattern by photolithography: The selected photoresist is SU-8 photoresist, the spin coating condition is 1500r / min, after spinning for 30s, drying at 95°C for 5min, and then covering it with a mask with a pattern size of 25×25cm. After exposing for 120s, drying at 95°C for 6min, and developing with developer PGMEA; finally, the sacrificial layer is removed by immersing the silicon wafer with the pattern in N-methylpyrrolidone to obtain a SU-8 film with a five-petal plum blossom pattern;

[0086] Example 2

[0087] The steps for synthesizing magnetically controlled MOF microrobots by self-assembly at the two-phase interface are as follows:

[0088] First, add 3 mL of zinc nitrate solution with a concentration of 0.17 mol / L into the container; then place the SU-8 membrane prepared in Example 1 on the aqueous solution; then add 1 mL of n-octanol solution containing Fe3O4 and 2-methylimidazole, and react for 120 minutes, wherein the content of Fe3O4 is 800 mg / mL and the concentration of 2-methylimidazole is 0.08 mol / L.

[0089] Example 3

[0090] The steps for synthesizing MOF microrobots by self-assembly at the two-phase interface are as follows:

[0091] First, 3 mL of zinc nitrate solution with a concentration of 0.17 mol / L was added to the container; then the SU-8 membrane prepared in Example 1 was placed on the aqueous solution; then 1 mL of 2-methylimidazole n-octanol solution was added, and the reaction was continued for 120 minutes. The concentration of 2-methylimidazole was 0.08 mol / L.

[0092] In this embodiment, the thickness of the obtained MOF robot is about 5 μm.

[0093] Example 4

[0094] The two-phase interface self-assembles to synthesize MOF microrobots of different shapes. The steps are as follows:

[0095] First, 3 mL of zinc nitrate solution with a concentration of 0.17 mol / L was added to the container; then SU-8 membranes with different patterns were placed on the aqueous solution; then 1 mL of 2-methylimidazole n-octanol solution was added, and the reaction was continued for 120 minutes. The concentration of 2-methylimidazole was 0.08 mol / L.

[0096] The preparation process of the SU-8 film with different patterns mentioned in this embodiment is the same as that in embodiment 1, except that the pattern in the mask is different from that in embodiment 1. The specific pattern is as follows: Figure 4 shown.

[0097] Example 5

[0098] The steps for amino modification of magnetically controlled MOF microrobots are as follows:

[0099] The magnetically controlled MOF microrobot prepared in Example 2 was added into a 3-amino-1,2,4-triazole solution with a solution concentration of 0.08 mol / L and a reaction time of 120 minutes at 50°C.

[0100] Example 6

[0101] The steps for loading lipase on the magnetically controlled MOF microrobot are as follows:

[0102] The amino-modified magnetically controlled MOF microrobot of Example 5 was placed in a lipase solution (ie, lipase was dissolved in PBS, the solution concentration was 2 mg / mL, and the concentration of PBS was 10 mM) and reacted for 12 hours.

[0103] Example 7

[0104] The steps of manipulation of the magnetically controlled MOF microrobot are as follows:

[0105] like Figure 7 As shown, the magnetically controlled MOF microrobot prepared in Example 6 can stand when a constant field (10 mT, 0.1 Hz) is applied, that is, perpendicular to the XY plane; when the magnetic field is removed, the magnetically controlled MOF microrobot returns to its original lying state; in addition, when an XY plane rotating field (10 mT 8 Hz) is applied, clockwise or counterclockwise rotation movement can be achieved by controlling the direction of rotation by a handle.

[0106] like Figure 8 As shown, when an XZ plane rotating field (7mT, 8Hz) is applied, combined with handle control, the magnetically controlled MOF microrobot can perform repetitive movements along a specified shape.

[0107] In addition, the spiral magnetically controlled microrobot can achieve efficient movement and reach the designated place by applying an XZ plane rotating field (3-10mT, 1-6Hz); the bowl-shaped magnetically controlled microrobot can move to the target position and pick up the target object by applying an XY plane rotating field (5-8mT, 8-15Hz) combined with handle control, thereby realizing the picking up and transportation of goods; the serrated magnetically controlled microrobot can achieve high-speed rotational motion and cut target cells or tissues through an XY plane rotating field (8-10mT, 8-10Hz) combined with handle control; the multi-petal plum blossom-shaped magnetically controlled microrobot uses different magnetic fields and frequencies (1-10mT, 0.1-35Hz) to study its movement behavior and the surrounding fluid dynamics, and can efficiently move and stir in liquids.

[0108] Example 8

[0109] The steps for degrading triglycerides using a magnetically controlled MOF microrobot are as follows:

[0110] Tributyrin was used as the degradation target, and four groups of experiments were set up:

[0111] Group A: Magnetically controlled MOF microrobot (Example 2),

[0112] Group B: Magnetically controlled MOF microrobot (Example 2) + magnetic field,

[0113] Group C: Magnetically controlled MOF microrobot loaded with lipase (Example 6),

[0114] Group D: Magnetically controlled MOF microrobot loaded with lipase (Example 6) + magnetic field; the efficiency of degradation of tributyrin in each group was compared.

[0115] Figure 1 The present invention shows a roadmap for preparing a customizable SU-8 film and synthesizing a magnetically controlled MOF microrobot through two-phase interface self-assembly, and the process is: 1) obtaining the SU-8 film by micro-nano processing; 2) synthesizing a magnetically controlled MOF microrobot by interface self-assembly; 3) amino-modifying the magnetically controlled MOF microrobot; 4) loading lipase onto the amino-modified magnetically controlled MOF microrobot by using the principle of ion adsorption.

[0116] Figure 2 The optical microscope image of the customizable magnetically controlled MOF microrobot prepared in Example 2 of the present invention is shown. Figure 2 It can be seen that the microrobots are arranged regularly and are about 140 microns in size.

[0117] Figure 3 The SEM and EDX element distribution diagrams of the customizable magnetically controlled MOF microrobot prepared in Example 2 of the present invention are shown. Figure 3 It can be seen that elements such as Fe, N, and Zn are evenly distributed on the surface of the magnetically controlled MOF microrobot.

[0118] Figure 4 The MOF microrobots without magnetic material of different shapes prepared in Example 4 of the present invention are shown.

[0119] Figure 5 A graph showing the relationship between the thickness of the MOF microrobot without magnetic material prepared in Example 3 of the present invention and time.

[0120] Testing of magnetically controlled MOF microrobots:

[0121] The microrobot prepared in Example 6 is placed in deionized water and then transferred to a PDMS tank, and its movement can be observed and recorded under the control of a magnetic field.

[0122] The movement speed of the microrobot changes with the frequency of the magnetic field. Figure 6 As shown, under different magnetic field strengths, the speed of the microrobot first increases and then decreases, and the speed reaches 379μm / s at 10mT 6Hz.

[0123] Figure 7 The motion behavior diagram of the customizable magnetically controlled MOF microrobot under the action of a constant magnetic field prepared in Example 6 shows that the MOF magnetically controlled microrobot is manipulated under the control of a constant magnetic field (10mT 0.1Hz), and the micro-nano robot can exhibit "standing" and "lying down" motion behaviors, thus proving that the motion behavior of the micro-nano robot can be controlled by the magnetic field.

[0124] Figure 8 The motion trajectory diagram of the customizable MOF magnetically controlled microrobot prepared in Example 6, which repeatedly moves 30 times along a rectangle under the control of a magnetic field (XZ plane, 7mT, 8Hz), is shown in FIG. Figure 8 It can be seen that precise control of the motion of the microrobot can be achieved under the control of the external magnetic field.

[0125] Fig. 9 The degradation of tributyrin in each group of Example 7 of the present invention is shown. After 55 minutes, the degradation rates of groups A to D were 5.53%, 14.39%, 80.94%, and 100%, respectively. Under the magnetic field, a higher degradation percentage was observed in the MMWRs loaded with lipase (Example 6), indicating that mechanical interactions enhance diffusion and thus enhance the degradation of tributyrin droplets. At the same time, the acid produced during the degradation process decomposes ZIF-8, further releasing lipase, forming a positive feedback mechanism, and accelerating the degradation of tributyrin droplets.

[0126] Fig.10 During the degradation of triglycerides under the experimental conditions of Group C in Example 7, the MOF microrobot decomposes under acidic conditions (i.e., the butyric acid produced by lipase in the process of catalyzing the degradation of tributyrin makes the microenvironment acidic with a pH of 4.56), and the area is reduced.

[0127] The above are only preferred specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A method for preparing a customizable MOF-based magnetically controlled microrobot, characterized in that: The following steps are involved: The magnetic MOF microrobot was prepared by coupling the micro-nanofabrication template method with the two-phase interface self-assembly method. The magnetic MOF microrobot is amino-modified by a ligand exchange method, and then lipase is loaded by an ion adsorption method, so as to finally obtain the customizable MOF-based magnetically controlled microrobot.

2. The method for preparing a customizable MOF-based magnetically controlled microrobot according to claim 1, characterized in that: The specific process of the micro-nano processing template method is as follows: A sacrificial layer is spin-coated on the silicon wafer, and after drying, a photoresist is spin-coated and dried, and then covered with a mask with a pattern, and then exposed, dried, developed and immersed in sequence to obtain a SU-8 film with the desired pattern.

3. The method for preparing a customizable MOF-based magnetically controlled microrobot according to claim 2, characterized in that: The pattern includes any one of a spiral, an S-shape, a triangle, a quadrilateral, a circle, a multi-petal plum blossom, a sawtooth or a bowl.

4. The method for preparing a customizable MOF-based magnetically controlled microrobot according to claim 1, characterized in that: The specific steps of the two-phase interface self-assembly method are: Firstly, a metal salt solution is added into a container; then, a SU-8 film is placed therein; and finally, an octanol solution containing Fe3O4 and an organic ligand is added therein to carry out a self-assembly reaction.

5. The method for preparing a customizable MOF-based magnetically controlled microrobot according to claim 4, characterized in that: The MOF constructed by the metal salt solution and the organic ligand includes any one of ZIF-8, HKUST-1, MOF-177, MOF-5 or MOF-74.

6. The method for preparing a customizable MOF-based magnetically controlled microrobot according to claim 1, characterized in that: The specific process of the ligand exchange method is: The magnetic MOF microrobot was immersed in a 3-amino-1,2,4-triazole solution and reacted at 50° C. for 120 minutes.

7. The method for preparing a customizable MOF-based magnetically controlled microrobot according to claim 1, characterized in that: The specific process of the ion adsorption method is: The amino-modified magnetically controlled MOF microrobot was placed in a lipase solution and reacted for 12 hours.

8. A customizable MOF-based magnetically controlled microrobot, characterized in that: The invention is prepared by the preparation method according to any one of claims 1 to 7.

9. A method for manipulating a customizable MOF-based magnetically controlled microrobot, characterized in that: The following steps are involved: Under the condition of applying an external magnetic field, the movement of the MOF-based magnetically controlled microrobot according to claim 8 is controlled by a handle; The external magnetic field conditions are: a constant field with a magnetic field of 1-10 mT and a frequency of 0.1-35 Hz; and / or Magnetic field 5-10 mT, frequency 8-15 Hz XY plane rotating field; and / or Magnetic field 3-10mT, XZ plane rotating field with frequency 1-6Hz.

10. Use of a customizable MOF-based magnetically controlled microrobot as claimed in claim 8 in the fields of triglyceride degradation, targeted drug delivery or thrombolytic treatment.

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