A mesoporous single-atom iron nanomaterial for self-catalysis, its preparation method and application

Abstract

This invention relates to a mesoporous single-atom iron nanoparticle self-catalyzing material, its preparation method, and its application. The mesoporous single-atom iron nanoparticle self-catalyzing material comprises: a mesoporous polydopamine framework, and Fe metal catalytic centers chelated in the mesoporous polydopamine framework in the form of single atoms; the mesoporous polydopamine framework has catechol functional groups.

Description

TECHNICAL FIELD

[0001] The present application relates to a mesoporous monatomic iron nano self-catalytic material and a preparation method and application thereof, in particular to a mesoporous monatomic nanocatalyst with a self-catalytic substrate, a high specific surface area, a mesoporous morphology and a uniform pore size distribution, and a related application of the nanocatalyst as a degradable, efficient and specific nanoreagent for tumor catalytic treatment, belonging to the technical field of microporous / mesoporous molecular materials. BACKGROUND

[0002] In the presence of a relatively high concentration of H2O2 and H + , Fenton nanocatalysts (such as Fe3O4 and 2DFePS3 nanosheets) can trigger intracellular Fenton reactions to produce highly oxidative hydroxyl radicals, causing oxidative damage to tumor cells. The effectiveness of tumor catalytic treatment based on Fenton reactions is positively correlated with the activity of catalytic reactions. Currently, strategies to improve catalytic reaction activity mainly include increasing substrate concentration and designing high-activity catalytic sites. For example, the dynamics of Fenton reactions are greatly affected by pH, because when the environmental pH is greater than 3.5, the reaction between Fe III and OH - generates Fe(OH)3precipitate. To enhance the effect of Fenton reactions in tumors, Bu et al. used carbonic anhydrase IX inhibitors to prevent the outflow of H + in cells to reduce the pH in cancer cells. By controlling other reaction conditions, such as increasing H2O2concentration, selecting appropriate catalysts, optimizing reaction temperature and time, etc., the optimization of Fenton reactions can also be achieved. Among these factors, the catalytic activity of the catalyst itself is the most critical factor affecting Fenton catalytic reactions. To improve the effectiveness, selectivity, biocompatibility and catalytic activity of nanocatalysts in anti-tumor therapy, higher requirements are needed for the design of nanocatalysts and the construction of catalytic conditions. For example, scientists have proposed strategies such as ligand chelation and heterogeneity carbon substrate immobilization of iron catalytic sites to prevent the formation of Fe(OH)3in the tumor microenvironment and improve the efficiency of Fenton reaction to produce hydroxyl radicals.

[0003] The rate-determining step of Fenton reaction is one of the important factors affecting the activity of catalysts and the efficiency of Fenton reaction. The rate-determining step of Fenton reaction is the reduction of high-valence Fe III metal species to low-valence Fe II (k = 9.1 x 10 -7 L mol -1 s -1 ), and Fe II is the main reaction species for catalyzing Fenton reaction. Therefore, promoting the circulation of Fe III to Fe II can effectively enhance the catalytic dynamics of Fenton reaction. SUMMARY

[0004] In view of the above problems, the present application aims to provide a self-catalytic mesoporous single-atom iron nanoscale self-catalytic material, a preparation method and application thereof.

[0005] In a first aspect, the present application provides a mesoporous single-atom iron nanoscale self-catalytic material, comprising: a mesoporous polydopamine framework, and Fe metal catalytic centers chelated in the form of single atoms in the mesoporous polydopamine framework; the mesoporous polydopamine framework has catechol functional groups.

[0006] In the present application, the mesoporous polydopamine is used as a support framework of single-atom catalytic sites: on the one hand, the Fe catalytic active sites of the mesoporous single-atom iron-based nanocatalyst produced in the preparation are isolated and dispersed in the framework, thereby improving the atomic utilization rate of metal atoms with catalytic activity; on the other hand, the catechol functional groups in the polydopamine framework can accelerate the conversion of Fe III to Fe II in the Fenton reaction process, thereby improving the Fenton reaction rate.

[0007] Preferably, the nanocatalytic material contains abundant hydroxyl and amino functional groups on the surface, and exhibits good physiological stability and biocompatibility, and can be used for efficient catalytic treatment of tumors in human bodies or other mammals.

[0008] Preferably, the mesoporous single-atom iron nanoscale self-catalytic material has a mesoporous spherical structure, and the average particle size is 80-110 nm, more preferably 80-90 nm.

[0009] The specific surface area of the mesoporous single-atom iron nanoscale self-catalytic material is 400-428 m 2 g -1 , and the mesopore size is 2.6-15 nm.

[0010] In addition, preferably, the nanocatalytic material has a mesoporous morphology, and the particle size is about 80 nm and the pore size is about 2.6 nm.

[0011] Preferably, the mesoporous single-atom iron nanoscale self-catalytic material can accelerate the conversion of Fe III to Fe II in the Fenton reaction process, thereby improving the Fenton reaction rate.

[0012] In a second aspect, the present application provides a preparation method of a mesoporous single-atom iron nanoscale self-catalytic material, comprising:

[0013] (1) adding a template agent, dopamine and an iron source into a solvent to mix, to obtain an organic compound mixture solution;

[0014] (2) adding an emulsifier into the obtained organic compound mixture solution to form a stable nanomicelle solution;

[0015] (3) adding a basic solution drop by drop into the obtained stable nanomicelle solution while stirring and mixing, and then centrifuging, washing and drying to obtain the mesoporous single-atom iron nano self-catalyst.

[0016] The preparation process of the present application is simple and easy to operate, pollution-free, high-yield, low-cost, high-efficiency, and the obtained mesoporous nano single-atom iron self-catalytic material has controllable particle size and good stability, which is conducive to the effective enrichment of drugs in tumor sites and produces excellent therapeutic effect, and is one of the tumor treatment schemes with extremely promising application prospect.

[0017] Preferably, in step (1), the solvent is a mixed solvent of water and anhydrous ethanol; the volume ratio of water to anhydrous ethanol in the mixed solvent of water and anhydrous ethanol is (1-2):1, preferably 1:1;

[0018] The template agent is a soft template, preferably a Pluronic block copolymer, more preferably at least one of Pluronic F127 and Pluronic P123;

[0019] The iron source is ferrous sulfate;

[0020] The mass ratio of the template agent to dopamine is (2000-600):500, preferably 1000:500;

[0021] The mass ratio of dopamine to the iron source is 500:(4-8);

[0022] The mixing method is water bath ultrasonic mixing, and the parameters of the water bath ultrasonic mixing include a water bath temperature of 20-40℃, an ultrasonic power of 500-600W, and a time of 0.1-0.5 hours.

[0023] Preferably, in step (2), the emulsifier includes mesitylene;

[0024] The proportion of the emulsifier in the mixture solution is 0.5%-4%, preferably 2%.

[0025] Preferably, in step (3), the basic solution is one of ammonia and Tris buffer solution; the concentration of the ammonia is 15-25wt%; the volume of the basic solution added is 3-5% of the volume of the stable nanomicelle solution, preferably 5%;

[0026] The stirring speed is 400-800rpm / min, and the stirring time is 0.5-1 hour; the stirring temperature is 20-40℃;

[0027] Preferably, the centrifugation speed is 13,000 to 20,000 rpm, and the time is 0.2 to 0.4 hours;

[0028] Preferably, the solvent used for washing includes a mixture of deionized water and ethanol in a ratio of (0.1-10):1, and the washing is performed at least three times.

[0029] Preferably, the drying is vacuum drying at a temperature of -20 to 10°C for at least 6 hours. Oxidative polymerization occurs during the stirring and mixing process.

[0030] Thirdly, the present invention provides an injection solution of mesoporous single-atom iron nanoparticle self-catalyzing material, comprising: a biocompatible solution, and the mesoporous single-atom iron nanoparticle self-catalyzing material dispersed in the biocompatible solution. Preferably, the mesoporous single-atom iron nanoparticle cocatalyst has a hydration kinetic diameter of 90–110 nm in the injection solution and exhibits good stability in in vitro physiological environments.

[0031] Preferably, the concentration of the mesoporous single-atom iron nanoparticle self-catalyst is 2.5–1000 μg / mL, more preferably 100–800 μg / mL, and even more preferably 250–400 μg / mL.

[0032] Preferably, the biocompatible solution is physiological saline or phosphate buffer.

[0033] Fourthly, this invention provides the application of a porous single-atom iron nanoparticle self-catalyzing material or a mesoporous single-atom iron nanoparticle self-catalyzing material injection solution in the preparation of a Fenton catalytic therapeutic agent for in vivo tumors, wherein the in vivo tumors have a weakly acidic microenvironment and are solid tumors with H2O2 overexpression. The aforementioned mesoporous single-atom iron nanoparticle co-catalyzing material can reach the tumor site and efficiently, continuously, and specifically catalyze the Fenton reaction to generate hydroxyl radicals in the weakly acidic and H2O2-overexpressing microenvironment of the tumor, inducing tumor cell apoptosis. During this process, the catechol functional groups in the framework of the mesoporous single-atom iron nanoparticle co-catalyzing material promote Fe2+ reaction through electron transfer. (II) The regeneration effectively enhances the Fenton reaction's ability to continuously generate free radicals. This invention proposes a nanocatalyst construction scheme for self-catalytic catalysis on an active substrate, which continuously generates highly toxic hydroxyl radicals at the tumor site, improving the efficiency of tumor-specific catalytic therapy. Furthermore, the mesoporous single-atom iron nanocatalyst possesses abundant pore space, allowing for synergistic functional design for tumor catalytic therapy and drug loading and delivery.

[0034] The beneficial effects of this invention are:

[0035] (1) The preparation method involved in this invention is simple, the operation is relatively simple, the product performance is stable, and it is beneficial for mass production.

[0036] (2) The mesoporous single-atom iron nanocatalyst prepared by the present invention has sustained Fenton reaction performance, which can promote the regeneration of ferrous ions with Fenton activity and realize efficient catalytic treatment of tumors.

[0037] (3) The nanocomposite material prepared by the present invention has high enrichment at the tumor site, high biosafety and degradability, and is expected to realize green treatment of tumors. Attached Figure Description

[0038] Figure 1 This is a flowchart illustrating the preparation of mesoporous single-atom iron nanoparticle self-help catalyst according to one embodiment of the present invention.

[0039] Figure 2 These are TEM (A) and SEM (B) images of the mesoporous single-atom iron nanoparticle self-catalyst material synthesized in Example 1, which visually demonstrate the mesoporous spherical morphology, uniform particle size, and good dispersibility of the catalyst.

[0040] Figure 3 The images show the dark-field image, corresponding EDS elemental distribution image (A), and atomic-level high-resolution image (B) of the mesoporous single-atom iron nanoparticle co-catalyst material synthesized in Example 1 under aberration-corrected HAADF-STEM mode. In the high-resolution image, red circles mark the atomically dispersed Fe atom catalytic sites. It can be clearly observed that C, N, O, and Fe elements are uniformly distributed within the mFePDA framework. No Fe ions show aggregation or phase separation, indicating that metal-ligand chelation enables the orderly dispersion and assembly of active sites. The aberration-corrected atomic-resolution HAADF-STEM image reveals numerous high-contrast bright spots at the atomic scale, and no aggregated Fe nanocrystals were found, further revealing that the Fe catalytic sites in the mesoporous spheres exhibit an atomic-level distribution.

[0041] Figure 4 The results of the colorimetric reaction of 3,3',5,5'-tetramethylbiphenylamine with hydrogen peroxide at different concentrations of mFePDA in Example 2 demonstrate that mFePDA has the ability to continuously generate hydroxyl radicals, and its oxidation performance is positively correlated with concentration.

[0042] Figure 5 It is mPDA and Fe in Example 2 (II) The electron spin resonance spectra of the reaction of @mPDA and mFePDA with hydrogen peroxide to generate hydroxyl radicals can prove that mFePDA exhibits better catalytic performance in generating hydroxyl radicals.

[0043] Figure 6 It is mPDA and Fe in Example 3 (II)The cytotoxicity experiment results of @mPDA and mFePDA after co-incubation with cells show that the ability of mFePDA to continuously generate hydroxyl radicals can improve the therapeutic effect of tumor oxidative death.

[0044] Figure 7 This is a morphology diagram of the catalytic material prepared in Comparative Example 3. Detailed Implementation

[0045] The present invention will be further illustrated by the following embodiments. It should be understood that the following embodiments are for illustrative purposes only and are not intended to limit the present invention.

[0046] This disclosure relates to a self-catalytic Fe... (II) This paper discloses regenerated mesoporous single-atom iron nanocatalysts, their preparation methods, and applications. More specifically, it relates to the preparation of mesoporous single-atom iron nanocatalysts, which exhibit good biocompatibility and sustained catalytic oxidation performance, and can be used for efficient catalytic therapy of tumors in humans or other mammals. For example, the mesoporous nanocatalyst has abundant functional groups on its surface, a size of approximately 80 nm, a pore size of approximately 2.6 nm, and a specific surface area of ​​approximately 403.8 m². 2 g -1 .

[0047] In this invention, see Figure 1 The preparation method of this mesoporous nanocatalyst includes: forming stable nanomicelles; dopamine-iron oxidative self-polymerization; and washing to remove excess soft template and emulsifier. The mesoporous single-atom iron nanocatalyst prepared by this invention has advantages such as good catalytic performance, high enrichment at tumor sites, good biosafety, and significant tumor inhibition effect. It can be used for tumor catalytic therapy in humans or other mammals, and is of great significance for the development of Fenton nanocatalysts and tumor catalytic oxidation materials. The technical challenge of this invention lies in selecting a suitable iron source and adding an appropriate amount to obtain a nanocatalyst with uniform morphology, ordered pores, and good dispersion.

[0048] In one embodiment of the present invention, the mesoporous single-atom iron nano-catalytic material has a simple synthesis process, is pollution-free, has high yield, low cost, is easy to mass-produce, has good therapeutic effects, and high biosafety, showing excellent clinical application prospects in the biomedical field. The following exemplarily illustrates the mesoporous single-atom iron nano-catalytic material provided by the present invention.

[0049] Water and anhydrous ethanol are mixed in a 1:1 volume ratio to form a miscible solvent.

[0050] A soft template agent (such as Pluronic F127), dopamine, and ferrous salt (ferrous ammonium sulfate) are added to the above solvent at a mass ratio of (2000-600):500:(8-4) (e.g., 1000:500:4). The mixture is then ultrasonically mixed in a water bath to dissolve its components. During this process, the soft template agent (Pluronic F127) forms stable micelles, and dopamine chelates and coordinates with ferrous ions.

[0051] A certain volume of emulsifier (such as mesitylene) is added to the above-mentioned organic compound mixture solution to form an emulsion system solution.

[0052] A certain amount of alkaline solution (e.g., ammonia) is added dropwise to the above emulsion system, and the mixture is stirred at a uniform speed at room temperature (e.g., stirring time 1 hour). After centrifugation and washing (e.g., more than 3 times), mesoporous single-atom iron nanocatalyst is obtained. Preferably, Pluronic F127, mesitylene, dopamine molecules and free iron are removed by repeated stirring, washing and centrifugation in a water / ethanol mixed solution. The centrifugation speed is preferably 18000 rpm.

[0053] In one embodiment of the present invention, mesoporous single-atom iron nanocatalysts are dispersed in physiological saline or phosphate buffer to obtain a mesoporous single-atom iron nanocatalyst injection solution of a certain concentration. The preparation method is as follows: the mesoporous single-atom iron nanocatalyst is first frozen and vacuum dried, and then resuspended in a certain volume of physiological saline or phosphate buffer to obtain a mesoporous single-atom iron nanocatalyst injection solution with adjustable concentration.

[0054] In this invention, the hydration kinetic diameter of the mesoporous single-atom iron nanocatalyst is 80–110 nm, and it exhibits good stability in in vitro physiological environments.

[0055] To test the tumor therapeutic performance of the mesoporous single-atom iron nanocatalyst of the present invention, for example, 100 μL of the mesoporous single-atom iron nanocatalyst injection solution was injected into Balb / c mice bearing a 4T1 breast cancer subcutaneous tumor model via the tail vein. The experimental results showed that, compared with the control group injected only with saline and the group injected with ferrous ion dispersion, the mesoporous single-atom iron nanocatalyst effectively inhibited the growth of subcutaneous tumors in mice, indicating that this Fenton catalyst with self-catalytic ferrous regeneration has good tumor therapeutic efficacy.

[0056] The following examples further illustrate the present invention in detail. It should also be understood that the following examples are only for further explanation of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-essential improvements and adjustments made by those skilled in the art based on the above description of the present invention are within the scope of protection of the present invention. The specific process parameters, etc., in the following examples are merely examples within a suitable range; that is, those skilled in the art can make appropriate selections within the appropriate range based on the description herein, and are not intended to be limited to the specific values ​​in the examples below.

[0057] Comparative Example 1

[0058] mPDA: The only difference between the preparation process of Comparative Example 1 and Example 1 is that no iron source (ferrous ammonium sulfate) was added.

[0059] Comparative Example 2

[0060] Fe II @mPDA: The preparation process of Comparative Example 2 is as follows: 200 mg of Comparative Example 1 and 4 mg of iron source are stirred for 0.5 to 1 hour, and then the sample is collected by centrifugation at 18000 rpm.

[0061] Comparative Example 3

[0062] The only difference between this comparative example and Example 1 is that the iron salt is ferric chloride. See also Figure 7 The resulting material exhibits poor dispersion and uniformity, and its pores are disordered.

[0063] Comparative Example 4

[0064] The only difference between this comparative example and Example 1 is that the amount of iron salt added is 40 mg. This comparative example 4 does not produce the mesoporous single-atom iron nanoparticle self-catalyzing material of this patent.

[0065] Example 1

[0066] 1.0 g of Pluronic F127 was added to 100 mL of a mixture of water and ethanol (1:1 ratio), and stirred until fully dissolved. Separately, 0.5 g of dopamine and 4 mg of ferrous ammonium sulfate were added to the same mixture, and the mixture was sonicated in a water bath for 10 minutes while stirring at 500 rpm until fully dissolved. Then, 2.0 mL of mesitylene was added under continuous stirring for 30 minutes to form a stable F127 / TMB / DA-Fe composite nanomicelle system. 5 mL of ammonia was added dropwise to the mixture, and stirring was continued (500 rpm) for 2 hours. Under alkaline conditions, dopamine oxidatively polymerized to form mesoporous nanospheres. The product was collected by centrifugation (18000 rpm) and washed at least three times with deionized water and ethanol to remove mesitylene, excess organic molecules, and ferrous ammonium sulfate. Finally, a mesoporous single-atom iron nanocatalyst was obtained, with an average particle size of approximately 80 nm, a pore size of approximately 2.6 nm, and a specific surface area of ​​approximately 403.8 m². 2 g -1 .

[0067] Figure 2 This is a TEM image of the mesoporous single-atom iron nanocatalyst synthesized in this embodiment, which clearly shows that it can maintain a regular mesoporous spherical morphology, uniform particle size and high dispersibility before and after modification.

[0068] Figure 3 These are HADDF-STEM elemental distribution maps and atomic-level high-resolution images of the mesoporous single-atom iron nanocatalyst of Example 1. It can be seen that Fe, C, N, and O elements are uniformly distributed, and Fe is dispersed in the organic framework as single atoms, without forming metal clusters. Furthermore, the mesoporous single-atom iron nanocatalyst obtained in Example 1 exhibits good stability and dispersibility in deionized water.

[0069] Example 2

[0070] To assess the catalytic oxidation performance of mesoporous single-atom nanocatalysts, 3,3',5,5'-tetramethylbiphenylamine was used as the chromogenic substrate for the oxidation reaction. 100 μL of a 3.2 mM solution of 3,3',5,5'-tetramethylbiphenylamine was added to each well of a 24-well plate, followed by 10 μL of a 1 mM H₂O₂ solution and an aqueous dispersion of mFePDA / mPDA. The concentration of mFePDA was set to 2.5 μg / L. -1 5 μg L -1 10 μg L -1 and 0 μg L -1 Finally, 180 μL of weakly acidic aqueous solution was added to obtain a total reaction solution of 300 μL. The absorbance of the reaction system at 652 nm was immediately read in an ELISA reader.

[0071] Figure 4 These are the catalytic oxidation performance results of mesoporous single-atom iron nanocatalysts at different concentrations in this embodiment. It can be seen that the self-catalytic Fe... (II) Regenerated mesoporous single-atom iron nanocatalysts can continuously and efficiently generate hydroxyl radicals, exhibiting good catalytic oxidation performance.

[0072] Figure 5 It is polydopamine nanoparticles mPDA, surface chelated Fe (II) Polydopamine nanoparticles Fe (II) Electron spin resonance (ESR) tests of the reaction of mPDA and mesoporous single-atom iron nanocatalyst mFePDA with hydrogen peroxide under weakly acidic conditions to generate hydroxyl radicals demonstrate that mFePDA has a better Fenton catalytic effect in generating hydroxyl radicals.

[0073] Example 3

[0074] Cytotoxicity testing: The cytotoxicity of the mesoporous single-atom iron nanocatalyst was tested using the classic CCK-8 cytotoxicity assay. In the CCK-8 colorimetric assay, cells were first inoculated at a concentration of 1 × 10⁻⁶ cells / mL. 4 Cells were inoculated into 96-well plates at a density of [number] wells and then cultured for 12 hours in a CO2 incubator at 37°C with 5% CO2 humidified air to allow cell adhesion. Next, cells were inoculated with polydopamine nanoparticles (mPDA) and surface-chelated Fe [polymers]. (II) Polydopamine nanoparticles Fe (II) @mPDA, Free Fe (II) The original medium was replaced with fresh medium containing ionic and mesoporous single-atom iron nanocatalyst mFePDA, followed by incubation for 48 hours. The medium containing the material was then discarded, and the cells were gently washed twice with PBS. 100 μL of RPMI-1640 or DMEM high-glucose medium containing 10% CCK-8 was added to each well, and the cells were incubated for 45 minutes. The absorbance at 450 nm was then read using a microplate reader. The ratio of absorbance of the experimental group to the control group represents the relative cell viability of the experimental group.

[0075] Figure 6 This is a graph showing the cytotoxicity test results of the materials in each experimental group in this experiment. The results indicate that mPDA did not affect the survival of 4T1 tumor cells, and Fe... (II) @mPDA and free Fe (II) The treatment caused slight damage to the cells, with cell viability rates of 60.5±2.1% and 67.4±3.7%, respectively. However, the cell viability rate of the mFePDA-treated group decreased sharply to only 25.7±2.6%. This demonstrates the effect of this autocatalytic Fe... (II) Regenerated mesoporous single-atom iron nanocatalysts are more effective than an equal amount of Fe(II) @mPDA and free Fe (II) It exhibits higher cytotoxicity and can induce more 4T1 tumor cell death.

Claims

1. A mesoporous single-atom iron nano-autocatalytic material, characterized in that, Comprise: a mesoporous polydopamine framework, and Fe metal catalytic centers chelated in the form of single atoms in the mesoporous polydopamine framework; The mesoporous polydopamine framework has catechol functional groups; The preparation method of the mesoporous single-atom iron nano self-catalytic material comprises: (1) adding a template agent, dopamine and an iron source into a solvent for mixing to obtain an organic compound mixture solution; wherein the iron source is ferrous ammonium sulfate; the mass ratio of the template agent to dopamine is (2000-600):500; and the mass ratio of dopamine to the iron source is 500:(4-8); (2) adding an emulsifier into the obtained organic compound mixture solution to form a stable nanomicelle solution; (3) adding a basic solution drop by drop into the obtained stable nanomicelle solution while stirring and mixing, and then performing centrifugation, washing and drying to obtain the mesoporous single-atom iron nano self-catalyst.

2. The mesoporous single-atom iron nano-autocatalytic material of claim 1, wherein, The mesoporous single-atom iron nano self-catalytic material has a mesoporous spherical structure, and the average particle size is 80-110 nm; The specific surface area of the mesoporous single-atom iron nano self-catalytic material is 400-428 m 2 g -1 , and the mesopore size is 2.6-15 nm.

3. The mesoporous single-atom iron nano-autocatalytic material of claim 2, wherein, The average particle size is 80-90 nm.

4. The mesoporous single-atom iron nano-autocatalytic material of claim 1 or 2, characterized in that, The mesoporous single-atom iron nano self-catalytic material can accelerate the transformation of Fe (III) to Fe (II) in the Fenton reaction process, thereby improving the Fenton reaction rate.

5. The mesoporous single-atom iron nano-autocatalytic material of claim 1, wherein, In step (1), the solvent is a mixed solvent of water and anhydrous ethanol; the volume ratio of water to anhydrous ethanol in the mixed solvent of water and anhydrous ethanol is (1-2):1; The template agent is a soft template; The mass ratio of the template agent to dopamine is 1000:500; The mixing mode is water bath ultrasonic mixing, and the parameters of the water bath ultrasonic mixing include a water bath temperature of 20-40°C, an ultrasonic power of 500-600 W, and a time of 0.1-0.5 hours.

6. The mesoporous single-atom iron nano-autocatalytic material of claim 5, wherein, The volume ratio of water to anhydrous ethanol in the mixed solvent of water and anhydrous ethanol is 1:

1.

7. The mesoporous single-atom iron nano-autocatalytic material of claim 5, wherein, The template agent is a Pluronic block copolymer.

8. The mesoporous single-atom iron nano-autocatalytic material of claim 5, wherein, The template agent comprises at least one of Pluronic F127 and Pluronic P123.

9. The mesoporous single-atom iron nano-autocatalytic material of claim 1, wherein, In step (2), the emulsifier comprises mesitylene; The proportion of the emulsifier in the mixture solution is 0.5%-4%.

10. The mesoporous single-atom iron nano-autocatalytic material of claim 9, wherein, The proportion of the emulsifier in the mixture solution is 2%.

11. The mesoporous single-atom iron nano-autocatalytic material of claim 1, wherein, In step (3), the basic solution is one of ammonia and Tris; the concentration of the ammonia is 15-25 wt%; and the volume amount of the basic solution added is 3-5% of the volume of the stable nanomicelle solution; The stirring and mixing speed is 400-800 rpm, the time is 0.5-1 hour, and the temperature during stirring and mixing is 20-40°C.

12. The mesoporous single-atom iron nano-autocatalytic material of claim 11, wherein, The volume amount of the basic solution added is 5% of the volume of the stable nanomicelle solution.

13. The mesoporous single-atom iron nano-autocatalytic material of claim 11, wherein, The centrifugation speed is 13000-20000 rpm, and the time is 0.2-0.4 hours.

14. The mesoporous single-atom iron nano-autocatalytic material of claim 11, wherein, The solvent used for washing comprises a mixed solution of deionized water and ethanol at a ratio of (0.1-10):1, and the number of washing is at least 3 times.

15. The mesoporous single-atom iron nano-autocatalytic material of claim 11, wherein, The drying is vacuum drying at a temperature of -20-10°C for at least 6 hours.

16. A mesoporous single-atom iron nano-autocatalytic material injection solution, characterized in that, Comprise: a biocompatible solution, and the mesoporous single-atom iron nano self-catalytic material of any one of claims 1-15 dispersed in the biocompatible solution.

17. The mesoporous single-atom iron nano-autocatalytic material injection fluid of claim 16, wherein, The mesoporous single-atom iron nano self-catalyst has a hydration kinetic diameter of 90-110 nm in the injection solution.

18. The mesoporous single-atom iron nano-autocatalytic material injection fluid of claim 16, wherein, The concentration of the mesoporous single-atom iron nano self-catalyst is 2.5-1000 μg / mL.

19. The mesoporous single-atom iron nano-autocatalytic material injection fluid of claim 18, wherein, The concentration of the mesoporous single-atom iron nano self-catalyst is 100-800 μg / mL.

20. The mesoporous single-atom iron nano-autocatalytic material injection solution of claim 18, wherein, The concentration of the mesoporous single-atom iron nano self-catalyst is 250-400 μg / mL.

21. The mesoporous single-atom iron nano-autocatalytic material injection of claim 16, wherein, The biocompatible solution is physiological saline or phosphate buffer.

22. Use of the mesoporous single-atom iron nano-autocatalytic material of any one of claims 1-15 or the mesoporous single-atom iron nano-autocatalytic material injection of any one of claims 16-21 in the preparation of a medicament for use as an in vivo tumor Fenton catalytic therapeutic agent, characterized in that, The in vivo tumor has a weakly acidic microenvironment, and the solid tumor overexpresses H2O2.

Images