Core-shell structure nano particle with mediated microenvironment for rheumatoid arthritis treatment and preparation method of core-shell structure nano particle

Abstract

The invention provides core-shell structure nanoparticles with a mediated microenvironment for rheumatoid arthritis treatment and a preparation method thereof.The preparation method comprises the steps that a calcium peroxide precursor is dissolved in absolute ethyl alcohol containing a surfactant, and calcium peroxide nanoparticles are obtained by adding an ammonia water solution and a hydrogen peroxide solution; the preparation method comprises the following steps: carrying out surface treatment on calcium peroxide nanoparticles by using tannic acid to form a tannic acid molecular layer on the surfaces of the calcium peroxide nanoparticles so as to obtain tannic acid modified calcium peroxide nanoparticles; and forming a metal phenolic network shell on the surface of the tannic acid modified calcium peroxide nano-particle by using cerium acetate to obtain the core-shell structure nano-particle.

Description

Technical Field

[0001] The present invention relates to the technical field of biomedical materials, and specifically to a core-shell structured nanoparticle with a microenvironment-mediated function for treating rheumatoid arthritis and a preparation method thereof. Background Art

[0002] As the global population ages, the incidence of chronic diseases continues to rise. Rheumatoid arthritis (RA), as a common chronic autoimmune disease, has a serious impact on people's quality of life. According to statistics from the World Health Organization, approximately 1% of adults worldwide suffer from RA, and the incidence rate is increasing year by year. The disease usually presents as symmetrical polyarthritis of the synovial joints of the hands or feet, followed by persistent inflammation of the joints, leading to joint swelling, pain, stiffness, and loss of function. It can also cause other systemic complications, such as cardiovascular disease and lung disease, which seriously affect patients' daily life and work ability, while also placing a serious burden on the socioeconomic system.

[0003] At present, the main treatments for RA include drug therapy, surgical treatment, and long-term rehabilitation care. Although these treatments can relieve symptoms to a certain extent, they are often accompanied by serious side effects and are difficult to achieve a cure. RA patients usually need long-term or even lifelong medication, which not only increases the economic burden, but may also lead to problems of drug tolerance and dependence. Therefore, the development of new, efficient, and low-toxic RA treatment strategies has become an urgent problem to be solved. In order to effectively meet this challenge, it is necessary to have a deep understanding of the pathological characteristics of RA and its microenvironmental characteristics.

[0004] The pathological characteristics of RA include chronic inflammation of the synovium, proliferation of synovial cells, and destruction of joints and cartilage. The RA microenvironment has the following notable characteristics: (1) Acidic environment: The RA microenvironment is usually acidic, which is mainly due to the increased metabolic activity of inflammatory cells, resulting in the accumulation of metabolites such as lactic acid, which reduces the local pH value; (2) Increased levels of reactive oxygen species (ROS): In the RA microenvironment, the levels of reactive oxygen species are significantly increased, including hydrogen peroxide (H2O2), superoxide (O2 - ) and hydroxyl radicals (OH·), which can cause oxidative stress and damage cells and tissues; (3) A large number of inflammatory factors: RA lesions are rich in a variety of inflammatory factors, including tumor necrosis factor α (TNF-α), interleukin-1 (IL-1), interleukin-6 (IL-6), etc. These inflammatory factors promote inflammatory reactions, leading to synovial hyperplasia and joint destruction; (4) Hypoxic environment: Due to inflammation and tissue hyperplasia, blood flow in RA lesions is reduced, leading to local tissue hypoxia. This hypoxic environment will further aggravate the inflammatory response and tissue damage.

[0005] In view of the above characteristics of the RA microenvironment, the application of nanotechnology in the treatment of RA shows great potential, especially in the field of drug delivery and targeted therapy. Due to its unique physical and chemical properties, nanomaterials can achieve specific release of drugs at the lesion site by regulating particle size, surface charge and functional modification, significantly improving the therapeutic effect and reducing side effects. At the same time, nanomaterials can also enhance the therapeutic effect by co-loading drugs. Summary of the invention

[0006] The purpose of the present invention is to provide a core-shell structured nanoparticle with a mediated microenvironment for the treatment of rheumatoid arthritis and a preparation method to overcome the deficiencies of the prior art. The present invention is a novel core-shell structured nanoparticle for the treatment of rheumatoid arthritis, wherein the core-shell structured nanoparticle has calcium peroxide as the core and a cerium-based metal phenolic network as the shell. The structural design is intended to utilize the characteristics of the RA microenvironment to achieve multifunctional therapeutic effects, including anti-inflammatory, anti-oxidation and promotion of cartilage repair.

[0007] The present invention is achieved through the following technical solutions: A method for preparing core-shell nanoparticles having a mediated microenvironment for treating rheumatoid arthritis comprises the following steps: Step 1: dissolving a calcium peroxide precursor in anhydrous ethanol containing a surfactant, and adding an ammonia solution and a hydrogen peroxide solution to obtain calcium peroxide nanoparticles; Step 2: using tannic acid to perform surface treatment on the calcium peroxide nanoparticles prepared in step 1, forming a tannic acid molecular layer on the surface of the calcium peroxide nanoparticles to obtain tannic acid-modified calcium peroxide nanoparticles; Step 3: Using cerium acetate to form a metal phenolic network shell on the surface of tannic acid-modified calcium peroxide nanoparticles to obtain core-shell structured nanoparticles.

[0008] Furthermore, the step 1 specifically comprises: using polyvinyl pyrrolidone as a surfactant and calcium chloride as a calcium peroxide precursor, adding an ammonia solution and a hydrogen peroxide solution as reaction substrates to react, and the obtained nanoparticles are calcium peroxide nanoparticles, which are centrifuged and washed several times with anhydrous ethanol to obtain calcium peroxide nanoparticles.

[0009] Furthermore, the mass ratio of the concentration of polyvinyl pyrrolidone to calcium chloride is 3:1, the concentrations of the ammonia solution and the hydrogen peroxide solution are both 1 mol / L, the amount of ammonia solution added is 1 / 15 of the volume of anhydrous ethanol, the amount of hydrogen peroxide solution added is 1 / 25 of the volume of anhydrous ethanol, and the reaction time is 60 min.

[0010] Furthermore, after the calcium peroxide precursor is dissolved in anhydrous ethanol containing a surfactant, the pH value is adjusted to be neutral, and then an ammonia solution and a hydrogen peroxide solution are added.

[0011] Furthermore, the pH value is adjusted to be neutral, specifically: the pH value is adjusted to 7 using sodium hydroxide.

[0012] Furthermore, the step 2 is specifically as follows: the calcium peroxide nanoparticles obtained in step 1 are uniformly dispersed in an anhydrous ethanol solvent by ultrasound, and then a tannic acid solution is added and stirred for reaction. After the reaction is completed, the calcium peroxide nanoparticles are separated by centrifugation and washed with anhydrous ethanol for several times to obtain tannic acid-modified calcium peroxide nanoparticles.

[0013] Furthermore, the concentration of the calcium peroxide nanoparticle dispersion solution formed by uniformly dispersing the calcium peroxide nanoparticles in anhydrous ethanol solvent by ultrasound is 1 mg / mL, the concentration of the tannic acid solution is 24 mM, the volume ratio of the calcium peroxide nanoparticle dispersion solution to the tannic acid solution is 10:1, and the stirring reaction time is 6 hours.

[0014] Furthermore, the step 3 specifically comprises: re-dispersing the tannic acid-modified calcium peroxide nanoparticles obtained in step 2 into anhydrous ethanol, adding the cerium acetate solution and vortexing to allow the cerium ions to fully react with the tannic acid, and after the reaction is completed, centrifugally separating and washing with anhydrous ethanol for several times to obtain core-shell structured nanoparticles with calcium peroxide as the core and the metal phenolic network as the shell.

[0015] Furthermore, the tannic acid modified calcium peroxide nanoparticles are dispersed in anhydrous ethanol, and the concentration of the obtained tannic acid modified calcium peroxide nanoparticle dispersion solution is 1 mg / mL, the concentration of the cerium acetate solution is 144 mM, the volume ratio of the tannic acid modified calcium peroxide nanoparticle dispersion solution to the cerium acetate solution is 10:1, and the vortex time is 5 min.

[0016] A core-shell structured nanoparticle with a mediated microenvironment for treating rheumatoid arthritis is prepared by the above-mentioned preparation method.

[0017] Compared with the prior art, the present invention has the following beneficial technical effects: The present invention is a method for preparing core-shell nanoparticles with a microenvironment-mediated function for the treatment of rheumatoid arthritis. First, the nanoparticles of the present invention have a unique structure and multifunctional therapeutic effects. The core-shell structure design allows calcium peroxide to be coated with a metal phenolic network, which can maintain stability and responsiveness in the RA microenvironment. When the nanoparticles enter the RA lesion area, the metal phenolic network rapidly decomposes and releases calcium peroxide due to the acidic environment of the area. In an aqueous environment, calcium peroxide can decompose to produce hydrogen peroxide (H2O2) and oxygen (O2), wherein hydrogen peroxide further decomposes to produce water and oxygen, providing an oxygen environment that helps tissue repair and relieve inflammation. At the same time, the calcium ions (Ca 2+ ) can promote cartilage formation and has a potential positive effect on joint repair in RA.

[0018] Secondly, the metal phenolic network shell of the present invention contains cerium ions and tannic acid components, which significantly enhances the antioxidant capacity of the nanoparticles. Cerium (Ce) is a rare earth metal with antioxidant activity. 3+ ) and tetravalent cerium ions (Ce 4+ ) can effectively remove free radicals, have significant antioxidant effects, and can reduce the damage of oxidative stress to joints. At the same time, tannic acid is a natural polyphenol that is widely present in plants and has multiple biological activities such as antioxidant, antibacterial and anti-inflammatory. Compared with the single-function treatment method in the prior art, the present invention not only significantly improves the treatment effect through multifunctional synergistic treatment, but also reduces the side effects on the body.

[0019] Thirdly, the nanoparticles of the present invention have good acidic responsiveness, can quickly respond and decompose in the acidic microenvironment of RA, accurately release drug components, and achieve targeted treatment. Compared with traditional systemic administration methods, the nanoparticles of the present invention can effectively avoid the side effects caused by the distribution of drugs throughout the body, and improve the safety and effectiveness of treatment.

[0020] At the same time, the nanoparticles of the present invention have excellent biocompatibility and safety. The decomposition products of calcium peroxide are harmless to the human body and do not cause toxic side effects. In addition, the use of cerium ions and tannic acid further reduces the risk in the treatment process. Compared with the treatment method using high-side effect drugs in the prior art, the nanoparticles of the present invention are more patient-friendly and have better biocompatibility and safety.

[0021] In terms of preparation method, the present invention also has significant advantages. The preparation process is simple and easy, does not require complicated equipment and process steps, and is suitable for industrial large-scale production. This not only reduces production costs and improves production efficiency, but also ensures the stability and consistency of nanoparticles. Functional core-shell structured nanoparticles can be prepared through simple reaction steps, making large-scale application possible.

[0022] The nanoparticles of the present invention also have excellent stability and long-term therapeutic effects. They can continuously release active ingredients in the body, provide long-term therapeutic effects, help to control RA conditions for a long time, and reduce the recurrence of the disease. In addition, the structural design of the nanoparticles ensures their stability in the body, and they are not easily rapidly degraded or cleared, further extending their therapeutic effect time.

[0023] In summary, the present invention provides an innovative, multifunctional synergistic nanoparticle for the treatment of rheumatoid arthritis. It is significantly superior to the existing technology in terms of therapeutic effect, safety, biocompatibility, preparation process, targeting and long-term efficacy, and has broad clinical application prospects and market promotion value. This breakthrough design is expected to bring new solutions to the treatment of RA, improve the quality of life of patients, alleviate their pain, and promote the development of related fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more intuitively show the technical solution of the present invention, the drawings used in the embodiments are briefly described. These drawings are only used to illustrate some embodiments of the present invention and are intended to help understand the specific content and technical details of the present invention. Therefore, these drawings should not be regarded as limiting the scope of the present invention. For those of ordinary skill in the art, other related diagrams can also be obtained based on these drawings without paying creative work.

[0025] Figure 1 This is a SEM photo of the surface morphology of calcium peroxide nanoparticles not modified by surfactant in Test Example 1; Figure 2 This is a SEM photo of the surface morphology of calcium peroxide nanoparticles with good dispersibility modified by surfactant in Test Example 2; Figure 3 This is a SEM photo of the surface morphology of the calcium peroxide nanoparticles in Test Example 2 modified with tannic acid in Test Example 3; Figure 4 This is a SEM photo of the surface morphology of the calcium peroxide in Test Example 2 coated with cerium (III) acetate and tannic acid in Example 1; Figure 5 This is a SEM photo of the surface morphology of the calcium peroxide in Test Example 2 coated with cerium (IV) nitrate and tannic acid in Example 2; Figure 6X-ray diffraction (XRD) patterns of different samples prepared in Test Example 2, Test Example 3, and Example 1; Figure 7 This is an X-ray energy spectrum (EDS) diagram of calcium peroxide with good dispersion prepared in Test Example 2; Figure 8 is an X-ray energy spectrum (EDS) image of the metal phenolic network-wrapped calcium peroxide particles prepared in Example 1; Fig. 9 This is a transmission electron scanning image of the metal phenolic network wrapped calcium peroxide particles prepared in Example 1, with the line scanning data graph on the left and the element distribution graph on the right; Fig.10 X-ray photoelectron spectroscopy (XPS) graphs of different samples prepared in Test Example 2, Test Example 3, and Example 1; Fig.11 This is the high-resolution spectrum of the Ce element of the metal phenolic network-wrapped calcium peroxide particles prepared in Example 1. DETAILED DESCRIPTION

[0026] The embodiments of the present invention will be described in detail below in conjunction with the examples. The implementation cases are preferred embodiments of the present invention and should not be used to limit the scope of the present invention. In the following examples, the methods and experimental equipment used are all conventional methods and instruments unless otherwise specified.

[0027] Test Example 1 The preparation method of calcium peroxide nanoparticles not modified by surfactant comprises the following specific steps: Under the assistance of ultrasound, 1 g of CaCl2 was dissolved in 150 ml of anhydrous ethanol to ensure that the solution was completely mixed. Subsequently, the pH value of the solution system was adjusted to 7 with sodium hydroxide, and the mixed solution was placed on a magnetic stirrer and stirred at a speed of 800 rpm. At the same time, 10 mL of 1 M NH3·H2O solution was slowly added under stirring, and the drop rate was controlled at about 1 drop / second to ensure uniform reaction. After the drop addition was completed, stirring was continued for 5 minutes to fully mix the solution, and then 6 mL of 1 M H2O2 solution was slowly added, and the drop rate was also controlled at about 1 drop / second. Stirring was maintained for 30 minutes, during which the solution gradually turned light blue, indicating that the reaction was proceeding smoothly. After the reaction was completed, the reaction solution was transferred to a centrifuge tube and centrifuged at a speed of 12000 rpm for 10 minutes to collect the precipitate. The collected precipitate was washed three times with ethanol, adding an appropriate amount of ethanol each time, shaking and mixing, and then centrifuging to remove unreacted substances and impurities. Finally, the washed precipitate was placed in a vacuum dryer and dried at 60 °C for 12 h to obtain pure calcium peroxide nanoparticle powder.

[0028] Test Example 2 The preparation method of calcium peroxide nanoparticles with good dispersibility modified by surfactant comprises the following specific steps: Under the assistance of ultrasound, 1 g of CaCl2 and 3 g of PVP were dissolved in 150 ml of anhydrous ethanol to ensure that the solution was completely mixed. Subsequently, the pH value of the solution system was adjusted to 7 with sodium hydroxide, and the mixed solution was placed on a magnetic stirrer and stirred at a speed of 800 rpm. At the same time, 10 mL of 1 M NH3·H2O solution was slowly added under stirring, and the drop rate was controlled at about 1 drop / second to ensure uniform reaction. After the drop addition was completed, stirring was continued for 5 minutes to fully mix the solution, and then 6 mL of 1 M H2O2 solution was slowly added, and the drop rate was also controlled at about 1 drop / second. Stirring was maintained for 30 minutes, during which the solution gradually turned light blue, indicating that the reaction was proceeding smoothly. After the reaction was completed, the reaction solution was transferred to a centrifuge tube and centrifuged at a speed of 12000 rpm for 10 minutes to collect the precipitate. The collected precipitate was washed three times with ethanol, adding an appropriate amount of ethanol each time, shaking and mixing, and then centrifuging to remove unreacted substances and impurities. Finally, the washed precipitate was placed in a vacuum dryer and dried at 60°C for 12 hours to obtain pure calcium peroxide nanoparticle powder.

[0029] Test Example 3 The preparation method of surface modification of calcium peroxide in Test Example 2 using tannic acid, the specific steps are as follows: Step 1, Synthesis of calcium peroxide nanoparticles: Under the assistance of ultrasound, 1 g of CaCl2 and 3 g of PVP were dissolved in 150 ml of anhydrous ethanol to ensure that the solution was completely mixed. Subsequently, the pH value of the solution system was adjusted to 7 with sodium hydroxide, and the mixed solution was placed on a magnetic stirrer and stirred at a speed of 800 rpm. At the same time, 10 mL of 1 M NH3·H2O solution was slowly added under stirring, and the drop rate was controlled at about 1 drop / second to ensure uniform reaction. After the drop addition was completed, stirring was continued for 5 minutes to fully mix the solution, and then 6 mL of 1 M H2O2 solution was slowly added, and the drop rate was also controlled at about 1 drop / second. Stirring was maintained for 30 minutes, during which the solution gradually turned light blue, indicating that the reaction was proceeding smoothly. After the reaction was completed, the reaction solution was transferred to a centrifuge tube and centrifuged at a speed of 12000 rpm for 10 minutes to collect the precipitate. The collected precipitate was washed three times with ethanol, adding an appropriate amount of ethanol each time, shaking and mixing, and then centrifuging to remove unreacted substances and impurities. Finally, the washed precipitate was placed in a vacuum dryer and dried at 60°C for 12 hours to obtain pure calcium peroxide nanoparticle powder.

[0030] Step 2: Surface modification of calcium peroxide: 10 mg of CaO2 nanoparticles were dissolved in 10 mL of anhydrous ethanol, and ultrasonic treatment was used to ensure that the nanoparticles were fully and evenly dispersed in the solution. Then 1 mL of 24 mM tannic acid (TA) solution was slowly added to the solution and stirred at room temperature for 6 hours using a magnetic stirrer. During the stirring process, tannic acid molecules gradually adsorbed onto the surface of the CaO2 nanoparticles to form a uniform and dense tannic acid molecule layer. After stirring, the solution was separated by a centrifuge, and the centrifugal conditions were set at 8000 rpm for 10 minutes to remove the unadsorbed tannic acid molecules. After centrifugation, the precipitate was washed with anhydrous ethanol to ensure that pure tannic acid-modified CaO2 nanoparticles were obtained. Finally, the nanoparticles were dried in a vacuum oven at 60 °C for 12 hours until dry tannic acid-modified CaO2 nanoparticles were obtained to ensure good stability and functionality.

[0031] Example 1 The preparation method of core-shell structured nanoparticles with a mediated microenvironment for the treatment of rheumatoid arthritis comprises the following specific steps: Step 1, Synthesis of calcium peroxide nanoparticles: Under the assistance of ultrasound, 1 g of CaCl2 and 3 g of PVP were dissolved in 150 ml of anhydrous ethanol to ensure that the solution was completely mixed. Subsequently, the pH value of the solution system was adjusted to 7 with sodium hydroxide, and the mixed solution was placed on a magnetic stirrer and stirred at a speed of 800 rpm. At the same time, 10 mL of 1 M NH3·H2O solution was slowly added under stirring, and the drop rate was controlled at about 1 drop / second to ensure uniform reaction. After the drop addition was completed, stirring was continued for 5 minutes to fully mix the solution, and then 6 mL of 1 M H2O2 solution was slowly added, and the drop rate was also controlled at about 1 drop / second. Stirring was maintained for 30 minutes, during which the solution gradually turned light blue, indicating that the reaction was proceeding smoothly. After the reaction was completed, the reaction solution was transferred to a centrifuge tube and centrifuged at a speed of 12000 rpm for 10 minutes to collect the precipitate. The collected precipitate was washed three times with ethanol, adding an appropriate amount of ethanol each time, shaking and mixing, and then centrifuging to remove unreacted substances and impurities. Finally, the washed precipitate was placed in a vacuum dryer and dried at 60°C for 12 hours to obtain pure calcium peroxide nanoparticle powder.

[0032] Step 2: Surface modification of calcium peroxide: 10 mg of CaO2 nanoparticles were dissolved in 10 mL of anhydrous ethanol, and ultrasonic treatment was used to ensure that the nanoparticles were fully and evenly dispersed in the solution. Then 1 mL of 24 mM tannic acid (TA) solution was slowly added to the solution and stirred at room temperature for 6 hours using a magnetic stirrer. During the stirring process, tannic acid molecules gradually adsorbed onto the surface of the CaO2 nanoparticles to form a uniform and dense tannic acid molecule layer. After stirring, the mixture was separated by a centrifuge, and the centrifugation conditions were set to 8000 rpm for 10 minutes to remove the unadsorbed tannic acid molecules. After centrifugation, the precipitate was washed with anhydrous ethanol to ensure that pure tannic acid-modified CaO2 nanoparticles were obtained. Finally, the nanoparticles were dried in a vacuum oven at 60°C for 12 hours until dry tannic acid-modified CaO2 nanoparticles were obtained to ensure good stability and functionality.

[0033] Step 3: Coating of metal phenolic network The nanoparticles obtained in step 2 were redispersed in 10 mL of anhydrous ethanol and ultrasonically treated to ensure uniform dispersion. Then, 1 mL of 144 mM cerium acetate (C6H9CeO6, Ce (III)) solution was added and the solution was vortexed in a vortex mixer for 5 minutes to ensure that the cerium ions fully contacted and reacted with the tannic acid on the surface of calcium peroxide to form a stable metal phenolic network. After the reaction, centrifuged at 8000 rpm for 10 minutes and washed three times with anhydrous ethanol. Finally, the precipitate was dried in a vacuum oven at 60 °C for 12 hours to obtain calcium peroxide nanoparticles wrapped in a metal phenolic network.

[0034] Example 2 The preparation method of core-shell structured nanoparticles with a mediated microenvironment for the treatment of rheumatoid arthritis comprises the following specific steps: Step 1, Synthesis of calcium peroxide nanoparticles: Under the assistance of ultrasound, 1 g of CaCl2 and 3 g of PVP were dissolved in 150 ml of anhydrous ethanol to ensure that the solution was completely mixed. Subsequently, the pH value of the solution system was adjusted to 7 with sodium hydroxide, and the mixed solution was placed on a magnetic stirrer and stirred at a speed of 800 rpm. At the same time, 10 mL of 1 M NH3·H2O was slowly added under stirring, and the drop rate was controlled at about 1 drop / second to ensure uniform reaction. After the drop addition was completed, stirring was continued for 5 minutes to fully mix the solution, and then 6 mL of 1 M H2O2 was slowly added, and the drop rate was also controlled at about 1 drop / second. Stirring was maintained for 30 minutes, during which the solution gradually turned light blue, indicating that the reaction was proceeding smoothly. After the reaction was completed, the reaction solution was transferred to a centrifuge tube and centrifuged at a speed of 12000 rpm for 10 minutes to collect the precipitate. The collected precipitate was washed three times with ethanol, adding an appropriate amount of ethanol each time, shaking and mixing, and then centrifuging to remove unreacted substances and impurities. Finally, the washed precipitate was placed in a vacuum dryer and dried at 60°C for 12 hours to obtain pure calcium peroxide nanoparticle powder.

[0035] Step 2: Surface modification of calcium peroxide: 10 mg of CaO2 nanoparticles were dissolved in 10 mL of anhydrous ethanol, and ultrasonic treatment was used to ensure that the nanoparticles were fully and evenly dispersed in the solution. Then 1 mL of 24 mM tannic acid (TA) solution was slowly added to the solution and stirred at room temperature for 6 hours using a magnetic stirrer. During the stirring process, tannic acid molecules gradually adsorbed onto the surface of the CaO2 nanoparticles to form a uniform and dense tannic acid molecule layer. After stirring, the solution was separated by a centrifuge, and the centrifugal conditions were set at 8000 rpm for 10 minutes to remove the unadsorbed tannic acid molecules. After centrifugation, the precipitate was washed with anhydrous ethanol to ensure that pure tannic acid-modified CaO2 nanoparticles were obtained. Finally, the nanoparticles were dried in a vacuum oven at 60 °C for 12 hours until dry tannic acid-modified CaO2 nanoparticles were obtained to ensure good stability and functionality.

[0036] Step 3: Coating of metal phenolic network The nanoparticles obtained in step 2 were redispersed in 10 mL of anhydrous ethanol and ultrasonically treated to ensure uniform dispersion. Then, 1 mL of 144 mM cerium nitrate (N3CeO9, Ce (IV)) solution was added and the solution was vortexed in a vortex mixer for 5 minutes to ensure that the cerium ions fully contacted and reacted with the tannic acid on the surface of calcium peroxide to form a stable metal phenolic network. After the reaction, centrifuged at 8000 rpm for 10 minutes and washed three times with anhydrous ethanol. Finally, the precipitate was dried in a vacuum oven at 60 ° C for 12 hours to obtain calcium peroxide nanoparticles wrapped in a metal phenolic network.

[0037] Figure 2 is a scanning electron image of the calcium peroxide nanoparticles prepared in the presence of the surfactant PVP in Test Example 2, compared with the calcium peroxide nanoparticles prepared in the absence of PVP in Test Example 1 ( Figure 1 ), in the presence of PVP, the particle morphology is significantly improved, showing a more uniform shape and size, and the boundaries between particles are clear, indicating that PVP, as a surface dispersant, significantly improves the dispersibility of nanoparticles and prevents the agglomeration of particles, thereby obtaining nanoparticles with more consistent size and more uniform distribution; Figure 3 This is a scanning electron image of the calcium peroxide nanoparticles surface-modified with tannic acid prepared in Test Example 3. After modification with tannic acid, the particle morphology is more regular, the surface is smooth, and the particle size is further uniformed. The TA coating not only improves the morphology of the nanoparticles, but also gives them better stability and functionality.

[0038] Figure 4 This is a scanning electron image of calcium peroxide nanoparticles wrapped with a trivalent cerium-based metal phenolic network in Example 1. It can be seen that the nanoparticles are closely connected, the surface has a granular feel and is uniform in size. The particle size is roughly around 100 nm, showing high uniformity and stability. Figure 5 This is a scanning electron image of calcium peroxide nanoparticles wrapped with a tetravalent cerium-based metal phenolic network in Example 2. The particle surface also shows a rough morphology with slight agglomeration. Figure 6 The X-ray diffraction spectra of different samples prepared in Test Example 2, Test Example 3, and Example 1 are shown. The appearance of the calcium peroxide peak indicates that it is successfully synthesized. Due to the formation of the metal phenolic network, the surface of the calcium peroxide particles is covered with an amorphous layer, resulting in a decrease in the overall crystallinity and a decrease in the peak value. Figure 7 This is the EDS spectrum of calcium peroxide prepared in Test Example 2, showing obvious Ca and O elements. When a layer of metal phenolic network is coated on its surface, Figure 8The main elements in the image are still Ca and O, but the peaks of Ce and C are newly added, and the surface metal phenolic network is successfully wrapped on the surface of calcium peroxide particles.

[0039] Fig. 9 This is a transmission electron image of the nanoparticle with a core-shell structure prepared in Example 1. The image shows two particles of about 100 nm in size. The line scan data of the energy spectrum analysis is superimposed on the image, where the peaks of Ca and O are concentrated in the central area of ​​the particles, and the peak of Ce is concentrated in the surface area of ​​the particles. The right side shows the distribution of different elements in the two particles. The comprehensive distribution diagram shows the overall distribution of Ca, O, and Ce. Ca and O are concentrated inside the particles, while cerium forms a coating on the surface of the particles, which is consistent with the expectation of the core-shell structure of the nanoparticles.

[0040] Fig.10 The X-ray photoelectron spectra of different samples prepared in Test Example 2, Test Example 3 and Example 1 are shown. The full scan spectrum confirms that the core-shell structured nanoparticles are mainly composed of C, O, Ca and Ce elements. High-resolution Ce 3d spectrum ( Fig.11 ) shows that the main peaks at 882 eV and 901.4 eV are attributed to Ce 4+ , while the peaks at 883.94eV, 843.94eV and 889.12eV correspond to Ce 4+ and Ce 3+ , confirming the existence of two different valence states of cerium in the core-shell nanoparticles, Ce 3+ and Ce 4+ The ratios of Ce in the core-shell nanoparticles are 35.9% and 64.1%. 3+ and Ce 4+ The ability to circulate between the two is a decisive factor in the successful removal of ROS and remodeling of macrophage phenotypes after being taken up by immune cells. The above results indicate that calcium peroxide nanoparticles encapsulated by cerium metal phenolic network have been successfully prepared.

[0041] In summary, the present invention provides a core-shell structured nanoparticle with a microenvironment-mediated function for the treatment of rheumatoid arthritis and a preparation method thereof. The nanoparticle has a unique core-shell structure design, combines the multiple functions of calcium peroxide and metal phenolic network (MPN), and achieves acid-responsive release in the microenvironment of rheumatoid arthritis.

[0042] The calcium peroxide in the core can generate hydrogen peroxide and oxygen in the microenvironment of the body, which helps to reduce inflammation and relieve joint pain. At the same time, the released calcium ions promote the regeneration and repair of cartilage. The outer metal phenolic network decomposes under acidic conditions, releasing cerium ions and tannic acid with antioxidant and free radical scavenging functions, effectively inhibiting oxidative stress in rheumatoid arthritis.

[0043] In addition, the nanoparticles also have the function of regulating immune cell functions. Specifically, it can promote the transformation of macrophages from pro-inflammatory M1 to anti-inflammatory M2, regulate the activity of other immune cells such as T cells, and thus improve the overall inflammatory response. At the same time, the nanoparticles also have the function of promoting chondrocyte differentiation and inhibiting osteoclast activity, further supporting the repair and regeneration of joint tissues.

[0044] The nanoparticles of the present invention not only have significant anti-inflammatory, antioxidant and immunomodulatory functions, but can also achieve precise release in a specific microenvironment, improving the effectiveness and safety of the drug. By integrating multiple therapeutic functions into one nanoplatform, the present invention provides an innovative, effective and potentially clinically valuable solution for the treatment of rheumatoid arthritis.

[0045] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Anyone familiar with this technology can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be based on the definition of the claims.

Claims

1. A method for preparing core-shell nanoparticles with a microenvironment-mediated structure for the treatment of rheumatoid arthritis, characterized in that: The following steps are involved: Step 1: dissolving a calcium peroxide precursor in anhydrous ethanol containing a surfactant, and adding an ammonia solution and a hydrogen peroxide solution to obtain calcium peroxide nanoparticles; Step 2: using tannic acid to perform surface treatment on the calcium peroxide nanoparticles prepared in step 1, forming a tannic acid molecular layer on the surface of the calcium peroxide nanoparticles to obtain tannic acid-modified calcium peroxide nanoparticles; Step 3: Using cerium acetate to form a metal phenolic network shell on the surface of tannic acid-modified calcium peroxide nanoparticles to obtain core-shell structured nanoparticles.

2. The method for preparing a core-shell structured nanoparticle having a microenvironment-mediated structure for treating rheumatoid arthritis according to claim 1, characterized in that: The step 1 specifically comprises: using polyvinyl pyrrolidone as a surfactant and calcium chloride as a calcium peroxide precursor, adding an ammonia solution and a hydrogen peroxide solution as reaction substrates to react, and the obtained nanoparticles are calcium peroxide nanoparticles, which are centrifuged and washed several times with anhydrous ethanol to obtain calcium peroxide nanoparticles.

3. The method for preparing a core-shell structured nanoparticle having a microenvironment-mediated structure for treating rheumatoid arthritis according to claim 2, characterized in that: The mass ratio of the polyvinyl pyrrolidone concentration to calcium chloride is 3:1, the concentrations of the aqueous ammonia solution and the hydrogen peroxide solution are both 1 mol / L, the amount of the aqueous ammonia solution added is 1 / 15 of the volume of anhydrous ethanol, the amount of the hydrogen peroxide solution added is 1 / 25 of the volume of anhydrous ethanol, and the reaction time is 60 min.

4. The method for preparing a core-shell structured nanoparticle having a microenvironment-mediated structure for treating rheumatoid arthritis according to claim 1, characterized in that: After the calcium peroxide precursor is dissolved in the anhydrous ethanol containing a surfactant, the pH value is adjusted to be neutral, and then an ammonia solution and a hydrogen peroxide solution are added.

5. The method for preparing a core-shell structured nanoparticle having a microenvironment-mediated structure for treating rheumatoid arthritis according to claim 4, characterized in that: The pH value is adjusted to be neutral, specifically: sodium hydroxide is used to adjust the pH value to 7.

6. The method for preparing a core-shell structured nanoparticle having a microenvironment-mediated structure for treating rheumatoid arthritis according to claim 2, characterized in that: The step 2 specifically comprises: uniformly dispersing the calcium peroxide nanoparticles obtained in the step 1 in an anhydrous ethanol solvent by ultrasound, then adding a tannic acid solution and stirring for reaction, and after the reaction is completed, performing centrifugal separation and washing with anhydrous ethanol for several times to obtain tannic acid-modified calcium peroxide nanoparticles.

7. The method for preparing a core-shell structured nanoparticle having a microenvironment-mediated structure for treating rheumatoid arthritis according to claim 6, characterized in that: The concentration of the calcium peroxide nanoparticle dispersion solution formed by uniformly dispersing the calcium peroxide nanoparticles in anhydrous ethanol solvent by ultrasound is 1 mg / mL, the concentration of the tannic acid solution is 24 mM, the volume ratio of the calcium peroxide nanoparticle dispersion solution to the tannic acid solution is 10:1, and the stirring reaction time is 6 hours.

8. The method for preparing a core-shell structured nanoparticle having a microenvironment-mediated structure for treating rheumatoid arthritis according to claim 1, characterized in that: The step 3 specifically comprises: re-dispersing the tannic acid-modified calcium peroxide nanoparticles obtained in step 2 into anhydrous ethanol, adding the cerium acetate solution and vortexing to allow the cerium ions to fully react with the tannic acid, and after the reaction is completed, centrifugally separating and washing with anhydrous ethanol for several times to obtain core-shell structured nanoparticles with calcium peroxide as the core and the metal phenolic network as the shell.

9. The method for preparing a core-shell structured nanoparticle having a microenvironment-mediated structure for treating rheumatoid arthritis according to claim 8, characterized in that: The tannic acid modified calcium peroxide nanoparticles are dispersed in anhydrous ethanol, and the concentration of the obtained tannic acid modified calcium peroxide nanoparticle dispersion solution is 1 mg / mL. The concentration of the cerium acetate solution is 144 mM. The volume ratio of the tannic acid modified calcium peroxide nanoparticle dispersion solution to the cerium acetate solution is 10:1, and the vortex time is 5 minutes.

10. A core-shell nanoparticle having a microenvironment-mediated structure for the treatment of rheumatoid arthritis, characterized in that: The method is prepared by the method according to any one of claims 1 to 9.

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