A controllable synthesis method of programmable perforated sheet-like MOF materials

Abstract

This invention discloses a controllable synthesis method for programmable perforated sheet-like MOF materials, aiming to solve the problems of cumbersome modification processes and low mass transfer efficiency and activity utilization in traditional MOF material modification. This method employs a one-pot in-situ synthesis strategy, abandoning complex etching processes. By precisely controlling reaction parameters such as the amount of sodium dodecyl sulfate (SDS), the controllable construction of MOF materials from monopores to porous structures is achieved, shortening the preparation cycle to 1.5 hours. By loading hemin chloride into the material and combining it with the "structure-activity positive structure-activity theory," the catalytic activity of the porous structure is verified to be significantly superior to that of the monopore structure. This material has a simple process, controllable cost, and can be used as a highly active carrier for biological probe loading, with wide applications in biosensing, immunoassay, and other fields, especially suitable for POCT detection scenarios, showing broad application potential.

Description

Technical Field

[0001] This invention belongs to the field of functional nanomaterial synthesis and catalytic materials technology, specifically involving the structural design and controllable preparation technology of metal-organic framework (MOF) materials. In particular, it relates to a one-pot synthesis method for programmable perforated sheet-like MOF materials. This material achieves controllable structure from monopore to multipore through precise regulation, and the catalytic activity of the porous structure has been verified to be significantly better than that of the monopore structure. It can be widely used in fields such as biosensing, immune detection, and catalytic reactions, providing technical support for the design and application of high-performance functional materials. Background Technology

[0002] The performance of a probe directly determines the overall effectiveness of a detection method. Currently, mainstream probe types include nucleic acid probes and immunoassay probes. Metal-organic frameworks (MOFs), as a class of novel functional materials with high specific surface area and porous structures, are widely used for probe loading to improve detection performance due to their theoretically high loading capacity. However, MOFs have significant limitations in practical applications: on the one hand, their small pore size and narrow pores hinder effective contact between the substrate and the probe, exacerbating the problem of slow mass transfer within the catalyst layer; on the other hand, if the MOF material is too large, it will generate significant steric hindrance, reducing mass transfer efficiency and preventing the internally loaded probe from fully exerting its activity, making it difficult to achieve a substantial improvement in detection performance.

[0003] To address the aforementioned shortcomings of MOF materials in probe loading applications, existing research has attempted to modify them by perforation through chemical or physical etching to increase specific surface area and contactable area, thereby improving the contact efficiency between the substrate and the catalyst and ultimately enhancing catalytic performance. However, this type of modification technology still has several drawbacks: First, the preparation process is cumbersome, requiring multiple etching steps, resulting in high process complexity and operational difficulty; second, the etching process easily causes the collapse of internal pores in the MOF material, leading to a significant decrease in probe loading and directly affecting detection results; third, the application scenarios are limited, currently confined to chemical catalysis fields such as fuel cells, and have not yet been extended to bioanalytical fields such as POCT detection, thus their application value in bioanalysis scenarios has not been effectively developed.

[0004] Addressing the bottlenecks of existing MOF material modification technologies, this invention innovatively employs a one-pot in-situ synthesis method for perforated sheet-like MOF materials. This eliminates the traditional, cumbersome multi-step etching process, significantly reducing the preparation cycle from 1-5 days to 1.5 hours, thereby substantially lowering process difficulty and cost. By precisely controlling key parameters such as the composition, temperature, and time of the reaction system, the controllable construction of MOF materials from monopores to porous structures is achieved. This significantly increases the material's contact area, fully exposing internally loaded probes and promoting rapid substrate penetration through the newly added interfaces, effectively shortening mass transfer distances and thus significantly improving catalytic reaction efficiency. Furthermore, this invention establishes a "structure-activity positive structure-activity theory," which clarifies that by directionally controlling the material's microstructure (e.g., optimizing from monopores to porous structures), the specific surface area can be effectively increased, the contact efficiency between the substrate and active sites can be enhanced, and the mass transfer path can be shortened, thereby directly and positively driving the improvement of catalytic activity. This provides crucial theoretical support for the rational design of catalytic materials. By loading Hemin small molecules into perforated sheet-like MOFs and conducting systematic performance comparison experiments between porous and monoporous structures, this invention successfully verified the scientific validity and feasibility of the theory, laying a solid foundation for the subsequent construction of high-performance nanozyme probes and integrated detection platforms.

[0005] The technical problems this invention aims to solve are as follows: Traditional MOF materials, when used as probe carriers, suffer from steric hindrance due to small pore size, narrow pores, or excessive volume, hindering effective contact between the substrate and the internal probe, resulting in low mass transfer efficiency, insufficient probe activity utilization, and difficulty in substantially improving detection performance; Existing MOF perforation modification relies on chemical / physical etching, requiring multiple cumbersome steps, with a preparation cycle of 1-5 days, high operational difficulty and cost, and is prone to pore collapse, leading to a decrease in probe loading and affecting application effects; The structure-activity relationship of catalytic materials lacks systematic theoretical support, making it difficult to achieve targeted enhancement of catalytic activity through precise structural control, necessitating the establishment of a scientific structure-activity theory and verification of its feasibility. Summary of the Invention

[0006] To address the shortcomings and deficiencies of existing MOF materials and modification technologies, such as cumbersome processes, low mass transfer efficiency, insufficient activity utilization, and unclear structure-activity relationships, this invention provides a controllable synthesis method and application of programmable perforated sheet-like MOF materials.

[0007] This invention employs a one-pot in-situ synthesis strategy, using metal ions as the central ion and organic ligands as the linkers, reacting in a mixed solvent without the need for etching. By precisely controlling parameters such as reaction system composition, temperature, and time, controllable synthesis of MOF materials from monopore to porous structures is achieved, shortening the preparation cycle to 1.5 hours and forming a sheet-like structure with high specific surface area, solving the problems of complex processes and low mass transfer efficiency in traditional methods. Simultaneously, a structure-activity relationship theory for catalytic materials is proposed. By loading Hemin small molecules into porous / monopore MOF materials, performance comparison experiments are conducted, verifying that porous structures are significantly superior to monopore structures in terms of mass transfer efficiency and probe activity utilization, providing theoretical support for catalytic material design. This perforated sheet-like MOF material can serve as a highly active carrier, adapting to the needs of biological probe loading, overcoming the limitation of existing modified MOF materials being used only for chemical catalysis, providing a high-performance material solution for bioanalytical fields such as POCT detection, and laying the foundation for subsequent nanozyme probe construction and detection platform integration.

[0008] The technical solution of this invention is as follows: A controllable synthesis method for programmable perforated sheet-like MOF materials is characterized by employing a one-pot in-situ synthesis strategy, abandoning the traditional complex etching process. Using metal ions as the central ion and organic ligands as the linkers, the method achieves controllable construction of MOF materials from monopores to multipores in a mixed solvent by precisely controlling key parameters such as reaction system composition, temperature, and time, thus preparing perforated sheet-like MOF materials with high specific surface area. By loading catalytically active molecules into this material and combining it with the structure-activity relationship theory, the catalytic performance of the material is significantly improved, making it suitable for applications in multiple fields such as biosensing and immunoassay.

[0009] In a first aspect, the present invention provides a perforated sheet-like MOF material, characterized in that: It has a microstructure that can be adjusted from single-pore to multi-pore; It has a sheet-like shape and possesses a high specific surface area and good structural stability; It can be used as a support to load catalytically active molecules, thereby achieving a high-efficiency improvement in catalytic performance.

[0010] Furthermore, the perforated sheet-like MOF material is synthesized via the following one-pot method:

[0011] Synthesis of single-pore ZIF material: 0.4 g of sodium dodecyl sulfate (SDS) was dissolved in 45 mL of deionized water under vigorous stirring at 25 °C, and the reaction was continued for 15 min. Then, 353.75 mg of cobalt nitrate hexahydrate was added, and the reaction was continued for another 15 min. 798.75 mg of 2-methylimidazole was dissolved in 5 mL of deionized water by sonication and added to the above system, and the reaction was carried out for 1 h. After the reaction was completed, the product was collected by centrifugation and washed three times with anhydrous ethanol to obtain the single-pore ZIF material.

[0012] Synthesis of porous ZIF material: 0.2 g sodium dodecyl sulfate (SDS) was dissolved in 45 mL of deionized water under vigorous stirring at 25 °C, and the reaction was continued for 15 min. Then, 353.75 mg of cobalt nitrate hexahydrate was added, and the reaction was continued for another 15 min. 798.75 mg of 2-methylimidazole was dissolved in 5 mL of deionized water by sonication and added to the above system, and the reaction was carried out for 1 h. After the reaction was completed, the product was collected by centrifugation and washed three times with anhydrous ethanol to obtain porous ZIF material.

[0013] Secondly, the present invention provides a perforated sheet-like MOF composite material loaded with catalytically active molecules, characterized in that: Using perforated sheet-like MOF materials as supports, Hemin small molecule catalytic active substances are loaded. The catalytic performance can be directionally regulated by controlling the pore structure (monopore / multipore) of MOF materials. The composite material is synthesized through the following steps:

[0014] Preparation of Hemin@ZIF monoporous composite material: 0.4 g sodium dodecyl sulfate (SDS) was dissolved in 45 mL of deionized water under vigorous stirring at 25 °C, and the reaction was continued for 15 min. Then, 1 mg hemin chloride and 353.75 mg cobalt nitrate hexahydrate were added sequentially, and the reaction was continued for 15 min. 798.75 mg 2-methylimidazole was dissolved in 5 mL of deionized water by sonication and added to the above system, and the reaction was carried out for 1 h. After the reaction was completed, the product was collected by centrifugation and washed three times with anhydrous ethanol.

[0015] Preparation of Hemin@ZIF porous composite material: 0.2 g sodium dodecyl sulfate (SDS) was dissolved in 45 mL of deionized water under vigorous stirring at 25 °C, and the reaction was continued for 15 min; then 1 mg hemin chloride (Hemin) and 353.75 mg cobalt nitrate hexahydrate were added sequentially, and the reaction was continued for 15 min; 798.75 mg 2-methylimidazole was dissolved in 5 mL of deionized water by sonication and added to the above system, and the reaction was carried out for 1 h; after the reaction was completed, the product was collected by centrifugation and washed 3 times with anhydrous ethanol.

[0016] Thirdly, the present invention provides a structure-activity positive structure-activity theory based on perforated sheet-like MOF materials, characterized in that:

[0017] By directionally controlling the microstructure of MOF materials (optimizing from monopore to porous), the contactable area of ​​the material can be effectively increased, the contact efficiency between the substrate and the active site can be enhanced, and the mass transfer path can be shortened, thereby directly and positively driving the improvement of the catalytic activity of the material.

[0018] The theory was verified through the following experiments: After the synthesized Hemin@ZIF single-well and porous materials were labeled by dynamic light scattering (DLS) and diluted to the same particle concentration, 50 μL of pH 4.5 acetate-sodium acetate buffer, 50 μL of 1 mM TMB solution, and 20 μL of Hemin@ZIF material suspension of the labeled concentration were added sequentially to the corresponding wells of a 96-well plate. Finally, 2.5 μL of 30% H2O2 solution was added and quickly mixed. The 96-well plate was placed in a microplate reader, and the absorbance value at a wavelength of 652 nm was monitored and recorded in real time under a constant temperature of 37℃, verifying that the catalytic activity of the porous structure was superior to that of the single-well structure.

[0019] The beneficial technical effects of this invention are:

[0020] 1. Highly efficient and robust fabrication process with controllable costs: Abandoning the traditional cumbersome post-etching process, we pioneered a "one-pot" method for in-situ controllable synthesis of perforated sheet-like MOF materials. This reduces the fabrication cycle from several days to 1.5 hours, effectively avoiding the risk of channel collapse caused by etching. The process is simple, reproducible, and inexpensive, making it easy to scale up for mass production.

[0021] 2. Optimized material structure, significantly improved mass transfer efficiency: By constructing a unique perforated sheet structure, the specific surface area and active site exposure rate of the material are significantly increased. This effectively solves the defects of traditional MOF materials such as small pore size and large steric hindrance, greatly shortens the substrate mass transfer distance, and achieves a dual improvement in mass transfer efficiency and probe activity utilization.

[0022] 3. Solid theoretical support and scientific guiding value: Through systematic comparative experiments of monoporous and porous structures, the "structure-activity positive structure-activity theory" was established and verified. This theory clarifies the positive driving mechanism of microstructure regulation on catalytic performance, providing a solid scientific basis for the targeted and rational design of high-performance nanozymes and biosensors.

[0023] 4. Sensitive and practical detection system, suitable for POCT needs: The detection platform, built upon the characteristics of a highly active carrier, enables ultrasensitive detection of target analytes. Furthermore, the system is easy to operate, responds quickly, and requires no large instruments, making it highly suitable for primary healthcare and point-of-care testing (POCT) applications, and possessing significant potential for clinical translation. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of this application or to compare with the prior art, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the following drawings are only some of the embodiments of this application, and those skilled in the art can derive other related drawings from these drawings without creative effort. In all drawings, the same or similar elements / parts are identified by the same or similar reference numerals to ensure consistency and readability of the drawings.

[0025] Figure 1 is a schematic diagram of the synthesis of the single-pore structure (A) and the porous structure (B) of the ZIF material of the present invention;

[0026] Figure 2 shows the transmission electron microscope (TEM) characterization images of the single-pore structure (A) and the porous structure (B) of the ZIF material of the present invention;

[0027] Figure 3 is a schematic diagram of the synthesis of the single-pore structure (A) and the porous structure (B) of the Hemin@ZIF material of the present invention;

[0028] Figure 4 shows the transmission electron microscopy (TEM) characterization images of the single-pore structure (A) and the porous structure (B) of the Hemin@ZIF material of the present invention;

[0029] Figure 5 shows the absorbance of the Hemin@ZIF porous structure and the monoporous structure of the present invention at a wavelength of 652 nm as a function of time. Detailed Implementation

[0030] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The specific embodiments described herein are only for explaining the present invention and are not intended to limit the present invention.

[0031] This invention provides a controllable synthesis method for programmable perforated sheet-like MOF materials. This method innovatively adopts a one-pot in-situ synthesis strategy, abandoning the traditional complex etching process. By precisely controlling the reaction parameters, the MOF materials can be constructed from single pores to multiple pores. At the same time, the "structure-activity positive structure-activity theory" is established, providing technical support and theoretical basis for the design and application of high-performance catalytic materials.

[0032] Specifically, the implementation process of this invention mainly includes the following key steps: First, perforated sheet-like MOF materials were prepared. Sodium dodecyl sulfate (SDS) was used as a dispersant, cobalt nitrate hexahydrate as a metal ion source, and 2-methylimidazole as an organic ligand. The reaction was carried out in deionized water via a one-pot reaction. By adjusting the amount of SDS, monoporous ZIF materials and porous ZIF materials were prepared respectively. After the reaction, the purified products were obtained by centrifugation and washing.

[0033] Secondly, MOF composites loaded with Hemin were prepared. Hemin chloride (Hemin) molecules were simultaneously added to the above MOF material synthesis system, and Hemin@ZIF monoporous composites and Hemin@ZIF porous composites were prepared by in-situ loading in a one-pot method. These were then centrifuged and washed before use.

[0034] Finally, the structure-activity positive structure-activity theory was verified. The two composite materials were calibrated by dynamic light scattering (DLS) and diluted to the same particle concentration to construct a catalytic reaction system. The absorbance change at 652 nm was monitored using a microplate reader, and the catalytic activity of the monoporous and porous structures was compared to verify the superiority of the porous structure.

[0035] Example 1: Preparation of monoporous and porous ZIF sheet materials 1.1 Preparation of single-pore ZIF materials: 1.1.1 At 25°C, add 0.4 g of sodium dodecyl sulfate (SDS) to 45 mL of deionized water, place on a magnetic stirrer and stir vigorously for 15 min to ensure that the SDS is completely dissolved; 1.1.2 Add 353.75 mg of cobalt nitrate hexahydrate to the above solution, keep stirring vigorously, and continue the reaction for 15 min to ensure that the metal ions are fully dispersed; 1.1.3 Take 798.75 mg of 2-methylimidazole, dissolve it in 5 mL of deionized water by sonication, and then quickly add it to the above reaction system. Stir vigorously for 1 hour. 1.1.4 After the reaction is complete, the reaction solution is transferred to a centrifuge tube, centrifuged in a high-speed centrifuge to collect the product, and washed three times with anhydrous ethanol to remove unreacted raw materials and impurities, thus obtaining a single-pore ZIF material; 1.1.5 Characterization: The morphology and structure of the prepared monoporous ZIF material were analyzed by transmission electron microscopy (TEM). The results showed that the material had a sheet-like structure with a monoporous morphology inside (see Figure 2A).

[0036] 1.2 Preparation of porous ZIF materials: 1.2.1 At 25°C, add 0.2 g of sodium dodecyl sulfate (SDS) to 45 mL of deionized water, place on a magnetic stirrer and stir vigorously for 15 min to ensure that the SDS is completely dissolved; 1.2.2 Add 353.75 mg of cobalt nitrate hexahydrate to the above solution, keep stirring vigorously, and continue the reaction for 15 min to ensure that the metal ions are fully dispersed; 1.2.3 Take 798.75 mg of 2-methylimidazole, dissolve it in 5 mL of deionized water by sonication, and then quickly add it to the above reaction system. Stir vigorously for 1 hour. 1.2.4 After the reaction is complete, the reaction solution is transferred to a centrifuge tube, centrifuged in a high-speed centrifuge to collect the product, and washed three times with anhydrous ethanol to remove unreacted raw materials and impurities, thus obtaining porous ZIF material; 1.2.5 Characterization: The morphology and structure of the prepared porous ZIF material were analyzed by transmission electron microscopy (TEM). The results showed that the material had a sheet-like structure with a porous interior (see Figure 2B).

[0037] Example 2: Preparation of Hemin@ZIF monoporous and porous composite materials 2.1 Preparation of Hemin@ZIF monoporous composite materials: 2.1.1 At 25°C, add 0.4 g of sodium dodecyl sulfate (SDS) to 45 mL of deionized water, place on a magnetic stirrer and stir vigorously for 15 min to ensure that the SDS is completely dissolved; 2.1.2 Add 1 mg of heme chloride (Hemin) and 353.75 mg of cobalt nitrate hexahydrate to the above solution in sequence, and continue to react for 15 min while maintaining vigorous stirring to ensure that Hemin and metal ions are fully dispersed and mixed. 2.1.3 Dissolve 798.75 mg of 2-methylimidazole in 5 mL of deionized water by sonication, then quickly add it to the above reaction system and stir vigorously for 1 h. 2.1.4 After the reaction was completed, the reaction solution was transferred to a centrifuge tube, centrifuged in a high-speed centrifuge to collect the product, and washed three times with anhydrous ethanol to remove unreacted raw materials and impurities, thus obtaining Hemin@ZIF monoporous composite material; 2.1.5 Characterization: The morphology and structure of the prepared composite material were analyzed by transmission electron microscopy (TEM). The results showed that Hemin was successfully loaded into the monoporous ZIF material (see Figure 4A).

[0038] 2.2 Preparation of Hemin@ZIF porous composite materials: 2.2.1 At 25°C, add 0.2 g of sodium dodecyl sulfate (SDS) to 45 mL of deionized water, place on a magnetic stirrer and stir vigorously for 15 min to ensure that the SDS is completely dissolved; 2.2.2 Add 1 mg of heme chloride (Hemin) and 353.75 mg of cobalt nitrate hexahydrate to the above solution in sequence, and continue to react for 15 min while maintaining vigorous stirring to ensure that Hemin and metal ions are fully dispersed and mixed. 2.2.3 Take 798.75 mg of 2-methylimidazole, dissolve it in 5 mL of deionized water by sonication, and then quickly add it to the above reaction system. Stir vigorously for 1 hour. 2.2.4 After the reaction was completed, the reaction solution was transferred to a centrifuge tube, centrifuged in a high-speed centrifuge to collect the product, and washed three times with anhydrous ethanol to remove unreacted raw materials and impurities, thus obtaining the Hemin@ZIF porous composite material; 2.2.5 Characterization: The morphology and structure of the prepared composite material were analyzed by transmission electron microscopy (TEM). The results showed that Hemin was successfully loaded into the porous ZIF material (see Figure 4B).

[0039] Example 3: Comparison of catalytic activity between Hemin@ZIF monoporous and porous composite materials 3.1 Material concentration calibration: Dynamic light scattering (DLS) technology was used to calibrate the particle size and concentration of Hemin@ZIF monoporous and porous composite materials, respectively. Then, the two materials were diluted to the same particle concentration for later use. 3.2 Construction of the catalytic reaction system: 50 μL of pH 4.5 acetate-sodium acetate buffer, 50 μL of 1 mM TMB solution, and 20 μL of Hemin@ZIF material suspension of a predetermined concentration were added sequentially to the corresponding wells of the 96-well plate. Finally, 2.5 μL of 30% H2O2 solution was added and quickly mixed. 3.3 Detection and Analysis: The 96-well plate was placed in a microplate reader, and the absorbance value at a wavelength of 652 nm was monitored and recorded in real time under a constant temperature of 37℃. The absorbance change curve over time was plotted. 3.4 Results: Experimental results show that the absorbance of the Hemin@ZIF porous composite material at a wavelength of 652 nm is significantly higher than that of the monoporous composite material, indicating that the porous structure has better catalytic activity and verifying the scientific validity of the "structure-activity positive structure-activity theory" (see Figure 5).

Claims

1. A method for the controllable synthesis of programmable perforated sheet-like MOF materials, characterized in that, Includes the following steps: (1) Preparation of single-pore ZIF material: 0.4 g sodium dodecyl sulfate (SDS) was dissolved in 45 mL of deionized water under vigorous stirring at 25 °C and the reaction was continued for 15 min; then 353.75 mg cobalt nitrate hexahydrate was added and the reaction was continued for 15 min; 798.75 mg 2-methylimidazole was dissolved in 5 mL of deionized water by sonication and added to the above system and the reaction was carried out for 1 h; after the reaction was completed, the product was collected by centrifugation and washed 3 times with anhydrous ethanol. (2) Preparation of porous ZIF material: 0.2 g sodium dodecyl sulfate (SDS) was dissolved in 45 mL of deionized water under vigorous stirring at 25 °C and the reaction was continued for 15 min; then 353.75 mg cobalt nitrate hexahydrate was added and the reaction was continued for 15 min; 798.75 mg 2-methylimidazole was dissolved in 5 mL of deionized water by sonication and added to the above system and the reaction was carried out for 1 h; after the reaction was completed, the product was collected by centrifugation and washed 3 times with anhydrous ethanol. (3) Preparation of Hemin@ZIF monoporous composite material: 0.4 g sodium dodecyl sulfate (SDS) was dissolved in 45 mL of deionized water under vigorous stirring at 25 °C and the reaction was continued for 15 min; then 1 mg hemin chloride (Hemin) and 353.75 mg cobalt nitrate hexahydrate were added in sequence and the reaction was continued for 15 min; 798.75 mg 2-methylimidazole was dissolved in 5 mL of deionized water by sonication and added to the above system and the reaction was carried out for 1 h; after the reaction was completed, the product was collected by centrifugation and washed 3 times with anhydrous ethanol. (4) Preparation of Hemin@ZIF porous composite material: 0.2 g sodium dodecyl sulfate (SDS) was dissolved in 45 mL of deionized water under vigorous stirring at 25 °C and the reaction was continued for 15 min; then 1 mg hemin chloride (Hemin) and 353.75 mg cobalt nitrate hexahydrate were added in sequence and the reaction was continued for 15 min; 798.75 mg 2-methylimidazole was dissolved in 5 mL of deionized water by sonication and added to the above system and the reaction was carried out for 1 h; after the reaction was completed, the product was collected by centrifugation and washed 3 times with anhydrous ethanol. (5) Validation of catalytic activity: After the Hemin@ZIF single-well and porous materials synthesized in steps (3) and (4) were calibrated by dynamic light scattering (DLS) and diluted to the same particle concentration, 50 μL of pH 4.5 acetate-sodium acetate buffer, 50 μL of 1 mM TMB solution and 20 μL of Hemin@ZIF material suspension with calibrated concentration were added to the corresponding wells of the 96-well plate in sequence. Finally, 2.5 μL of 30% H2O2 solution was added and quickly mixed. The 96-well plate was placed in a microplate reader and the absorbance value at 652 nm wavelength was monitored and recorded in real time under constant temperature of 37℃ to verify the catalytic activity of the porous structure.

2. The synthesis method according to claim 1, characterized in that, In steps (1)-(4), the temperature of all reactions is controlled at 25℃, the stirring method is vigorous stirring, 2-methylimidazole is dissolved in 5mL of deionized water by ultrasonication before being added to the reaction system, and the products are collected by centrifugation after the reaction is completed, and washed 3 times with anhydrous ethanol to remove impurities.

3. The synthesis method according to claim 1, characterized in that, In steps (1) and (3), the amount of SDS used is 0.4g, and in steps (2) and (4), the amount of SDS used is 0.2g. By adjusting the amount of SDS, the structure of MOF material from monopore to multipore can be controlled.

4. The synthesis method according to claim 1, characterized in that, In steps (3) and (4), the amount of Hemin added is 1 mg, and the order of addition is after SDS is dissolved and before cobalt nitrate hexahydrate is added, so as to achieve in-situ loading of Hemin in MOF material.

5. The synthesis method according to claim 1, characterized in that, In the reaction system for verifying catalytic activity in step (5), the pH of the acetate-sodium acetate buffer solution was 4.5, the TMB solution concentration was 1 mM, the H2O2 solution mass fraction was 30%, the detection temperature was 37℃, and the detection wavelength was 652 nm.

6. The synthesis method according to any one of claims 1-5, characterized in that, The perforated sheet-like MOF material can serve as a highly active carrier, adapting to the requirements of biological probe loading, and can be applied in fields such as biosensing, immunoassay, and catalytic reactions, especially suitable for bioanalytical scenarios such as POCT detection.

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