A magnesium-ethylene glycol tetraacetate nano-drug, a preparation method and use thereof

Abstract

This invention belongs to the field of biomedical nanomaterials and radiation damage drugs, specifically relating to a magnesium-ethylene glycol tetraacetic acid (EGTA) nanomedicine, its preparation method, and its applications. This study proposes using magnesium-EGTA nanomedicine to treat radiation dermatitis. EGTA's chelating ability for calcium ions is significantly higher than that of magnesium ions and other metal ions. Its unique ion selectivity provides an important theoretical basis and application potential for targeting and inhibiting mitochondrial calcium overload in the pathological process of radiation dermatitis. Magnesium ions are cofactors of many enzymes and have anti-inflammatory, collagen synthesis-promoting, and angiogenesis-enhancing effects. This study constructs a Mg-EGTA-based nanomedicine system, utilizing EGTA's stronger chelating ability for calcium ions, thereby achieving targeted regulation of mitochondrial calcium homeostasis through a calcium-magnesium ion intelligent replacement mechanism in response to calcium overload, providing new ideas and methods for the prevention and treatment of radiation dermatitis.

Description

Technical Field

[0001] This invention belongs to the field of biomedical nanomaterials and radiation damage drugs, specifically relating to a magnesium-ethylene glycol tetraacetic acid nanodrug, its preparation method, and its uses. Background Technology

[0002] Radiation dermatitis is a common skin complication in cancer patients after radiotherapy, affecting up to 95% of those receiving the treatment. Its clinical manifestations range from mild erythema and dry desquamation to moist desquamation, exudation, bleeding, crusting, and even difficult-to-heal ulcers and necrosis. This damage not only severely impacts patients' quality of life but also frequently leads to radiotherapy interruptions, directly affecting the effectiveness of cancer treatment. With the continued rise in global cancer incidence, the prevention and treatment of radiation dermatitis has become a major challenge in clinical practice.

[0003] Treatment options for radiation dermatitis are diverse, but their effectiveness is limited. Conventional treatments include basic wound care, corticosteroids, growth factors, and surgery, but these methods cannot address the core pathological issue of impaired skin barrier repair caused by calcium ion homeostasis imbalance. Current technologies cannot actively and specifically remove excess calcium ions from the pathological area, leading to toxicity issues in normal areas.

[0004] Furthermore, current nanomedicines for radiation dermatitis often treat both mitochondrial calcium overload and barrier repair simultaneously. Separate treatments targeting mitochondrial calcium overload and barrier repair often interfere with each other, leading to poor efficacy. The main reason is that during the repair phase of radiation dermatitis, keratinocytes shift from migration to proliferation and differentiation, and the epidermal calcium gradient is gradually rebuilt; during this phase, calcium... 2+ Maintaining calcium levels at 1.5-2 times the baseline often hinders barrier repair when calcium overload is suppressed. Therefore, it is necessary to develop a treatment for radiation dermatitis. Summary of the Invention

[0005] The purpose of this invention is to provide a magnesium-ethylene glycol tetraacetic acid (EGTA) nanomedicine, its preparation method, and its applications. This study proposes the use of magnesium-ethylene glycol tetraacetic acid (EGTA) nanomedicine to treat radiation dermatitis. EGTA's chelating ability for calcium ions is significantly higher than that of magnesium ions and other metal ions. Its unique ion selectivity provides an important theoretical basis and application potential for targeting and inhibiting mitochondrial calcium overload in the pathological process of radiation dermatitis. Magnesium ions are cofactors of many enzymes and have anti-inflammatory, collagen synthesis-promoting, and angiogenesis-promoting effects. This study constructs a Mg-EGTA-based nanomedicine system, utilizing EGTA's stronger chelating ability for calcium ions, thereby achieving targeted regulation of mitochondrial calcium homeostasis through a calcium-magnesium ion intelligent replacement mechanism in response to calcium overload, providing a new idea and method for the prevention and treatment of radiation dermatitis.

[0006] The technical problem solved by this invention is achieved by the following technical solution: In a first aspect, this invention provides a method for preparing magnesium-ethylene glycol tetraacetic acid nanomedicine, comprising the following steps: (1) Dissolve the magnesium source and the dispersant in the first buffer solution to obtain a magnesium source dispersion; dissolve ethylene glycol tetraacetic acid in the second buffer solution to obtain an ethylene glycol tetraacetic acid solution; (2) The magnesium source dispersion is mixed with the ethylene glycol tetraacetic acid solution and a self-assembly reaction is carried out under stirring to obtain a Mg-EGTA solution; (3) The Mg-EGTA solution was purified and lyophilized to obtain the magnesium-ethylene glycol tetraacetic acid nanomedicine.

[0007] In one or more embodiments of the present invention, the preparation method includes the following steps: (1) Dissolve magnesium chloride and polyvinylpyrrolidone in Tris solution to obtain magnesium source dispersion; dissolve ethylene glycol tetraacetic acid in Tris solution to obtain ethylene glycol tetraacetic acid solution; (2) The magnesium source dispersion and the ethylene glycol tetraacetic acid solution are mixed and subjected to a self-assembly reaction under stirring to obtain a Mg-EGTA solution; (3) The Mg-EGTA solution was purified by dialysis and lyophilized to obtain the magnesium-ethylene glycol tetraacetic acid nanomedicine.

[0008] This invention involves mixing the aforementioned magnesium source dispersion, ethylene glycol tetraacetic acid (EGTA), and polyvinylpyrrolidone (PVP) to conduct a coordination-self-assembly reaction. In this invention, EGTA, as a functionalized chelating ligand, specifically coordinates with magnesium ions through its multiple carboxyl groups, promoting the formation of stable, spherical nanoassemblies. Compared to other carboxylic acid chelating agents, EGTA exhibits high selectivity and affinity for divalent metal ions (especially magnesium ions). Its flexible molecular framework and multidentate coordination characteristics contribute to the construction of structurally regular nanoparticles and endow the system with good biodegradability and low toxicity. Furthermore, polyvinylpyrrolidone (PVP) forms an effective steric hindrance protective layer on the nanoparticle surface, preventing Ostwald ripening and aggregation of the Mg-EGTA complex during preparation and storage, thereby ensuring the long-term stability and size uniformity of the nanostructure. The benzene ring structure in the EGTA molecule can interact weakly with the carbonyl group in the polyvinylpyrrolidone chain segment. At the same time, the long chain of PVP can be interspersed between the EGTA-magnesium coordination network, further guiding the orderly arrangement of assembly units, inhibiting disordered aggregation, and improving the monodispersity and morphological controllability of the assembly.

[0009] The present invention does not have any special requirements for the mixing method; any mixing method well known in the art can be used, such as stirring.

[0010] In one or more embodiments of the present invention, step (3) involves a stirring rate of 500-600 rpm, a temperature of 45-50°C, and a time preferably of 3-6 hours, more preferably 6 hours. By controlling the stirring and mixing conditions, the present invention ensures the uniform dissolution of the magnesium source and dispersant.

[0011] In one or more embodiments of the present invention, the concentration of magnesium ions in the magnesium source dispersion in step (1) is 0.94-0.97 mol / L.

[0012] In one or more embodiments of the present invention, the concentration of magnesium ions in the magnesium source dispersion is 0.95-0.96 mol / L. In one or more embodiments of the present invention, the concentration of magnesium ions in the magnesium source dispersion is 0.957 mol / L.

[0013] In one or more embodiments of the present invention, the concentration of polyvinylpyrrolidone in the mixture in step (3) is 0.00018-0.00021 mol / L.

[0014] In one or more embodiments of the present invention, the concentration of the polyvinylpyrrolidone is 0.00018-0.00020 mol / L.

[0015] In one or more embodiments of the present invention, the concentration of the polyvinylpyrrolidone is 0.00019-0.00020 mol / L.

[0016] In one or more embodiments of the present invention, the concentration of the polyvinylpyrrolidone is 0.00019 mol / L.

[0017] In one or more embodiments of the present invention, the concentration of ethylene glycol tetraacetic acid in the ethylene glycol tetraacetic acid solution of the mixture in step (3) is 0.12-0.15 mol / L.

[0018] In one or more embodiments of the present invention, the concentration of the ethylene glycol tetraacetic acid is 0.12-0.14 mol / L.

[0019] In one or more embodiments of the present invention, the concentration of ethylene glycol tetraacetic acid is 0.1327 mol / L.

[0020] In one or more embodiments of the present invention, the temperature of the self-assembly reaction in step (3) is 45-60°C and the stirring time is 3-9 hours.

[0021] In one or more embodiments of the present invention, the temperature of the self-assembly reaction is 45-50°C and the stirring time is 3-6 hours.

[0022] In one or more embodiments of the present invention, the temperature of the self-assembly reaction is 48-52°C and the stirring time is 5-7 hours.

[0023] In one or more embodiments of the present invention, the temperature of the self-assembly reaction is 50°C and the stirring time is 6 hours.

[0024] In one or more embodiments of the present invention, the coordination-self-assembly reaction is preferably carried out under stirring conditions, the self-assembly temperature is preferably 45-50°C, more preferably 50°C, and the time is preferably 3-6 hours, more preferably 6 hours. The present invention enables the carboxyl groups of EGTA to coordinate with magnesium ions through self-assembly, forming a stable nanostructure. After the self-assembly reaction, the present invention does not perform post-processing and directly uses the resulting reaction solution for the next purification step. After centrifugation, the present invention collects the supernatant, and performs dialysis and lyophilization on the obtained supernatant. In the present invention, the molecular weight cutoff of the dialysis bag used for dialysis is preferably 20 × 10⁻⁶. 4 In this invention, dialysis is preferably performed under stirring conditions, with a stirring rate preferably of 200 rpm; the dialysis temperature is preferably room temperature, and the dialysis time is preferably overnight. This invention removes impurities from a solution through dialysis.

[0025] In one or more embodiments of the present invention, dialysis in step (4) is performed using a dialysis bag, wherein the molecular weight cutoff of the dialysis bag is preferably 10-30 × 10⁻⁶. 4 DA, stirring speed 150-250 rpm, dialysis temperature 10-40℃, room temperature, dialysis time 6-24h.

[0026] In one or more embodiments of the present invention, the molecular weight cutoff of the dialysis bag is preferably 18-22 × 10⁻⁶. 4 DA, stirring speed 180-220 rpm, dialysis temperature 10-30℃, room temperature, dialysis time 8-16h.

[0027] In one or more embodiments of the present invention, the molecular weight cutoff of the dialysis bag is preferably 20 × 10⁻⁶. 4 DA, stirring speed 200 rpm, dialysis temperature 20-25℃, room temperature, dialysis time 10-14h.

[0028] In one or more embodiments of the present invention, it is formed by coordination self-assembly of magnesium ions and ethylene glycol tetraacetic acid.

[0029] In one or more embodiments of the present invention, the particle size of the nanomedicine is 50-200 nm.

[0030] In one or more embodiments of the present invention, the particle size of the nanomedicine is 50-100 nm. In one or more embodiments of the present invention, the particle size of the nanomedicine is 50 nm.

[0031] In a second aspect, the present invention provides a pharmaceutical composition comprising the above-described magnesium-ethylene glycol tetraacetic acid nanomedicine, and a pharmaceutically acceptable carrier.

[0032] In a third aspect, the present invention provides the use of the magnesium-ethylene glycol tetraacetic acid nanomedicine composition in the preparation of a medicament for treating radiation dermatitis.

[0033] Magnesium-ethylene glycol tetraacetic acid (EGTA) nanomedicines target and regulate mitochondrial calcium homeostasis through an intelligent ion exchange mechanism, which is beneficial for the development of drugs to treat radiation dermatitis.

[0034] In one or more embodiments of the present invention, the radiation dermatitis is caused by tumor radiotherapy.

[0035] This invention provides a method for preparing Mg-EGTA nanomedicine, comprising the following steps: mixing a magnesium source and a dispersant to obtain a magnesium source dispersion; mixing the magnesium source dispersion with ethylene glycol tetraacetic acid (EGTA), and subjecting the mixture to a self-assembly reaction under stirring conditions; and obtaining a magnesium-EGTA nanomedicine (denoted as Mg-EGTAnanodrug, Mg-EGTA) after dialysis and lyophilization. This invention constructs a Mg-EGTA nanomedicine system, utilizing EGTA's stronger chelating ability for calcium ions, thereby achieving targeted regulation of mitochondrial calcium homeostasis and inhibiting cellular calcium overload through a calcium-magnesium ion intelligent replacement mechanism in response to calcium overload, thus achieving the therapeutic effect of radiation dermatitis.

[0036] The Mg-EGTA nanomedicine prepared by this invention has excellent biocompatibility and high therapeutic effect, and has the characteristics of low preparation cost and simple operation. It has broad clinical application prospects in the treatment of radiation dermatitis, especially in blocking radiation-induced cellular calcium overload. Attached Figure Description

[0037] Figure 1 This is a TEM image of the Mg-EGTA nanomedicine in Example 1.

[0038] Figure 2 The image shows the XPS spectrum of the Mg-EGTA nanomedicine in Example 1.

[0039] Figure 3The images show the cell viability of L929 cells after co-incubation with Mg-EGTA nanomedicine for 24 hours (A) and 48 hours (B) in Example 1.

[0040] Figure 4 This is a cell activity graph of Mg-EGTA nanomedicine co-incubated with L929 cells after radiation damage for 24 hours in Example 1.

[0041] Figure 5 The results show the targeting of Mg-EGTA to L929 cell mitochondria in Example 1; (A) Confocal plot of Mg-EGTA uptake by cells, scale bar 25 μm; (B) Statistical analysis of the average fluorescence intensity of Mg-EGTA uptake by L929 cells; (C) Flow cytometry plot of Mg-EGTA uptake by L929 cells; (D) Flow cytometry statistical plot of Mg-EGTA uptake by L929 cells.

[0042] Figure 6 The results show the blocking effect of Mg-EGTA nanomedicine on intracellular redox signal crosstalk in Example 1; (A) Confocal evaluation of Mg-EGTA nanomedicine inhibiting cellular calcium overload, scale bar 25 micrometers; (B) Statistical graph of average fluorescence intensity of the effect of calcium overload; (C) Flow cytometry graph of calcium overload; (D) Statistical graph of flow cytometry of calcium overload.

[0043] Figure 7 The results of Mg-EGTA nanomedicine scavenging reactive oxygen species in Example 1 are shown below: (A) Confocal plot of ROS scavenging by Mg-EGTA nanomedicine, scale bar 25 μm; (B) Statistical analysis of average fluorescence intensity of ROS scavenging by Mg-EGTA nanomedicine; (C) Flow cytometry plot of ROS scavenging by Mg-EGTA nanomedicine; (D) Statistical flow cytometry plot of ROS scavenging by Mg-EGTA nanomedicine.

[0044] Figure 8 This is an evaluation of the migration of Mg-EGTA nanomedicine in L929 cells in Example 1.

[0045] Figure 9 This is an experiment on HUVEC cell angiogenesis using Mg-EGTA nanomedicine, as shown in Example 1.

[0046] Figure 10 This serves as an evaluation of the animal experiment results for the treatment of radiation dermatitis with Mg-EGTA nanomedicine in Example 1.

[0047] Figure 11 This is an evaluation of the visceral results of animal experiments using Mg-EGTA nanomedicine to treat radiation dermatitis, as described in Example 1.

[0048] Figure 12This is an evaluation of the immunohistochemical results of IL-6 and TNF-α in animal experiments of Mg-EGTA nanomedicine for the treatment of radiation dermatitis in Example 1.

[0049] Figure 13 This is an animal hemolysis experiment of Mg-EGTA nanomedicine for the treatment of radiation dermatitis, as shown in Example 1.

[0050] Unless otherwise stated, the terms used in the specification and claims have the following meanings.

[0051] As described in this invention, the term "prevention" refers to preventing the occurrence of disease and / or preventing the recurrence of disease. Detailed Implementation

[0052] This specification provides a detailed description of specific embodiments. Those skilled in the art should recognize that the following embodiments are exemplary and should not be construed as limiting the invention. For those skilled in the art, various improvements and modifications can be made to the invention without departing from its principles; such improvements and modifications also fall within the scope of protection of the claims. The beneficial effects of the invention are illustrated below through specific examples.

[0053] Example 1

[0054] The preparation of Mg-EGTA involves the following steps: (1) Dissolve 175.2 mg of ethylene glycol tetraacetic acid in 1 mL of Tris solution, and ensure complete dissolution by sonication. Then add the solution dropwise to a reaction flask containing 4 mL of Tris solution. Stir at 50°C using a constant temperature stirrer at 500 rpm for 5 minutes. Add 66 mg of polyvinylpyrrolidone to the above solution and stir at 500 rpm for 5 minutes. Ethylene glycol tetraacetic acid solution is obtained.

[0055] (2) Dissolve 546.8 mg of magnesium chloride in 1 mL of Tris solution and obtain a magnesium source dispersion by ultrasonic dissolution.

[0056] (3) The magnesium source dispersion was added dropwise to the ethylene glycol tetraacetic acid solution and stirred at 500 rpm for 3-6 h at 50°C.

[0057] (4) After the reaction is complete, the solution is removed and transferred to a dialysis bag. It is then dialyzed overnight at 200 rpm to remove impurities from the solution. Finally, the dialyzed solution is collected, filtered through a 220 μm filter membrane, and lyophilized to obtain purified Mg-EGTA nanomedicine.

[0058] Example 2

[0059] The preparation of Mg-EGTA involves the following steps: (1) Dissolve 160 mg of ethylene glycol tetraacetic acid in 1 mL of Tris solution, and sonicate to ensure complete dissolution. Then add the solution dropwise to a reaction flask containing 4 mL of Tris solution. Stir at 50°C using a constant temperature stirrer at 500 rpm for 5 minutes. Add 60 mg of polyvinylpyrrolidone to the above solution and stir at 500 rpm for 5 minutes. Ethylene glycol tetraacetic acid solution is obtained.

[0060] (2) Dissolve 500 mg of magnesium chloride in 1 mL of Tris solution and obtain a magnesium source dispersion by ultrasonic dissolution.

[0061] (3) The magnesium source dispersion was added dropwise to the ethylene glycol tetraacetic acid solution and stirred at 500 rpm for 3-6 h at 50°C.

[0062] (4) After the reaction is complete, the solution is removed and transferred to a dialysis bag. It is then dialyzed overnight at 200 rpm to remove impurities from the solution. Finally, the dialyzed solution is collected, filtered through a 220 μm filter membrane, and lyophilized to obtain purified Ru-Cur.

[0063] Structural characterization (1) TEM morphology image of Mg-EGTA obtained in Example 1 is shown below. Figure 1 As shown. Mg-EGTA, after dialysis purification, was collected and its morphology was observed using transmission electron microscopy (TEM, Talos FEI 200). The TEM morphology image of the obtained Mg-EGTA is shown below. Figure 1 As shown in the figure, Mg-EGTA has an irregular shape, and the surface scan results indicate that the nanoparticles contain Mg on their surface, exhibiting high specific surface area and active site aggregation effect. The XPS spectrum of Mg in Mg-EGTA obtained in Example 1 is shown below. Figure 2 As shown, Mg exists in the form of Mg-O.

[0064] (2) XPS characterization: The lyophilized Mg-EGTA powder was characterized by X-ray photoelectron spectroscopy (XPS) using a Thermo Kalpha instrument. The XPS spectrum of Mg element in the obtained Mg-EGTA is shown below. Figure 2 As shown.

[0065] Performance testing (1) To verify the toxicity of Mg-EGTA to mouse fibroblasts (L929 cells), the CCK-8 assay was used (the experimental results are shown in Figure 3): Ru-Cur cytotoxicity assessment: L929 cells were seeded at a density of 2 × 10³ cells per well in 96-well plates and incubated overnight to promote cell adhesion. Subsequently, cells were treated with different concentrations of Mg-EGTAr, with final concentrations of 0, 6.25, 12.5, 25, 50, and 100 µg / mL, for incubation times of 24 h and 48 h. After incubation, CCK-8 reagent (100T, catalog number BS350A) was added to each well, and the cells were further incubated at 37 °C for 2 h. Finally, absorbance was measured at 450 nm using a microplate reader to assess cell viability. CCK-8 assay was used: Mg-EGTAr and L929 cells were co-incubated for 24 h each (…). Figure 3 A) and 48h Figure 3 After B), cell viability did not decrease significantly, indicating that Ru-Cur has no obvious toxicity to HOK cells.

[0066] (2) To verify that Mg-EGTA inhibits radiation damage to mouse fibroblasts (L929 cells), L929 cells were seeded into 96-well plates at a density of 2 × 10³ cells per well and incubated overnight to promote cell adhesion. The results were detected using the CCK-8 assay (see experimental results below). Figure 4 (As shown): After L929 cells were irradiated with 6 Gy, Mg-EGTA was co-incubated with L929 cells for 24 h. Then, CCK-8 reagent (100T, catalog number BS350A) was added to each well, and the cells were further incubated at 37°C for 2 h. Finally, the absorbance was measured at 450 nm using a microplate reader to assess cell viability. A significant increase in cell viability indicates that Mg-EGTA has a significant effect in protecting against radiation damage.

[0067] (3) To verify the targeting of Mg-EGTA to L929 cell mitochondria, the experimental results (Figure 5) show that Mg-EGTA can effectively reach the mitochondria of L929 cells.

[0068] (4) To further verify the blocking effect of Mg-EGTA nanomedicine on intracellular redox signal crosstalk, the experimental results (Figure 6) show that Mg-EGTA nanomedicine can significantly inhibit cellular calcium overload caused by 6 Gy X-ray irradiation; at the same time, as shown in Figure 7, it can effectively remove irradiation-induced reactive oxygen species (ROS), thereby exerting excellent anti-inflammatory activity.

[0069] (5) To further verify the effect of magnesium ions released after calcium overload ion exchange on the migration ability of L929 cells, experimental results (e.g.) were obtained. Figure 8As shown in the figure, Mg-EGTA can significantly alleviate the radiation-induced inhibition of L929 cell migration and effectively promote the recovery of L929 cell migration ability. Based on this, it can play a positive role in the treatment of radiation dermatitis by accelerating the repair process of damaged skin and mucous membranes.

[0070] (6) To further verify the effect of calcium and magnesium ion replacement of Mg-EGTA on the angiogenesis ability of HUVEC cells, the experimental results (e.g.) Figure 9 As shown in the figure, Mg-EGTA can significantly alleviate the radiation-induced inhibition of angiogenesis in HUVEC cells and effectively promote the recovery of HUVEC cell angiogenesis capacity. Based on this, it can play a positive role in the treatment of radiation dermatitis by accelerating the repair process of damaged skin and mucous membranes.

[0071] (7) To further verify the therapeutic effect of Mg-EGTA on radiation dermatitis in mice, this invention conducted preliminary animal experiments. BALB / c mice used in the experiment were purchased from Chengdu Dashuo Experimental Animal Co., Ltd., and all animal experimental procedures were strictly performed in accordance with the experimental protocol approved by the company's animal ethics committee. The experimental animals were housed in a standard animal room with a constant light-dark cycle of 12 hours of light / 12 hours of darkness. They were divided into two groups: the 50Gy X-ray group and the Mg-EGTA+X-ray group. After routine anesthesia, the mice were fixed in a special device, and a single 50Gy X-ray irradiation was performed on the local target area of ​​the right hind leg of each group of mice using an X-Rad320 small animal irradiator. After irradiation, the mice were returned to their cages and kept in a routine manner. Mice in the Mg-EGTA+X-ray group were given 1mg / mL Mg-EGTA, and mice in the 50Gy X-ray group were given PBS once a day.

[0072] Skin tissue, after dewaxing and hydration, was stained with hematoxylin (purchased from Sigma-Aldrich) and eosin (purchased from Hefei Bomei Biotechnology Co., Ltd.), then dehydrated, cleared, mounted with neutral resin, and photographed. Liver / kidney function indicators in serum / plasma were detected using a fully automated biochemical analyzer. The reagents ALT, AST, and CREA were all purchased from Shenzhen Mindray Bio-Medical Electronics Co., Ltd. Heart, liver, spleen, lungs, and kidneys were stained with hematoxylin and eosin (H&E).

[0073] The experimental results (as shown in Figure 10) showed that on days 0, 7, and 21 after X-ray irradiation treatment, the control group mice exhibited significant inflammatory reactions on the right leg skin, while the Mg-EGTA-treated group showed a significant reduction in inflammation. These results indicate that Mg-EGTA can effectively inhibit X-ray irradiation-induced radiation dermatitis.

[0074] Experimental results (such as) Figure 11As shown in the figure, no obvious inflammation was observed in the heart, liver, spleen, lungs, and kidneys of the mice above the surface, indicating that Mg-EGTA has no toxic side effects on rats.

[0075] Experimental results (such as) Figure 12 As shown in the figure): Immunohistochemical results of IL-6 and TNF-α in the skin of the right leg of mice treated with X-ray irradiation showed that the levels of IL-6 and TNF-α in the control group mice were significantly higher than those in the treatment group mice. These results indicate that Mg-EGTA can effectively inhibit the occurrence of inflammatory factors in X-ray irradiation-induced radiation dermatitis.

[0076] Experimental results (such as) Figure 13 As shown in the figure): Animal hemolysis experiments of Mg-EGTA nanomedicine for the treatment of radiation dermatitis showed that Mg-EGTA has excellent blood compatibility and no hemolytic reaction occurred after contact with mouse blood.

[0077] This invention specification provides a detailed description of specific embodiments. Those skilled in the art should recognize that the above embodiments are exemplary and should not be construed as limiting the invention. For those skilled in the art, various improvements and modifications can be made to the invention without departing from its principles, and the resulting technical solutions also fall within the scope of protection of the claims of this invention.

Claims

1. A method for preparing magnesium-ethylene glycol tetraacetic acid nanomedicine, characterized in that, Includes the following steps: (1) Dissolve the magnesium source and the dispersant in the first buffer solution to obtain a magnesium source dispersion; dissolve ethylene glycol tetraacetic acid in the second buffer solution to obtain an ethylene glycol tetraacetic acid solution; (2) The magnesium source dispersion is mixed with the ethylene glycol tetraacetic acid solution and a self-assembly reaction is carried out under stirring to obtain a Mg-EGTA solution; (3) The Mg-EGTA solution was purified and lyophilized to obtain the magnesium-ethylene glycol tetraacetic acid nanomedicine.

2. The preparation method according to claim 1, characterized in that, Includes the following steps: (1) Dissolve magnesium chloride and polyvinylpyrrolidone in Tris solution to obtain magnesium source dispersion; dissolve ethylene glycol tetraacetic acid in Tris solution to obtain ethylene glycol tetraacetic acid solution; (2) The magnesium source dispersion and the ethylene glycol tetraacetic acid solution are mixed and subjected to a self-assembly reaction under stirring to obtain a Mg-EGTA solution; (3) The Mg-EGTA solution was purified by dialysis and lyophilized to obtain the magnesium-ethylene glycol tetraacetic acid nanomedicine.

3. The preparation method according to claim 1 or 2, characterized in that, In step (1), the concentration of magnesium ions in the magnesium source dispersion is 0.94-0.97 mol / L; preferably, the concentration of magnesium ions in the magnesium source dispersion is 0.95-0.96 mol / L; more preferably, the concentration of magnesium ions in the magnesium source dispersion is 0.957 mol / L.

4. The preparation method according to claim 1 or 2, characterized in that, In step (3), the concentration of polyvinylpyrrolidone in the mixture is 0.00018-0.00021 mol / L; preferably, the concentration of polyvinylpyrrolidone is 0.00018-0.00020 mol / L; more preferably, the concentration of polyvinylpyrrolidone is 0.00019 mol / L.

5. The preparation method according to claim 1 or 2, characterized in that, In step (3), the concentration of ethylene glycol tetraacetic acid in the ethylene glycol tetraacetic acid solution of the mixture is 0.12-0.15 mol / L; preferably, the concentration of ethylene glycol tetraacetic acid is 0.12-0.14 mol / L; more preferably, the concentration of ethylene glycol tetraacetic acid is 0.1327 mol / L.

6. The preparation method according to claim 1 or 2, characterized in that, In step (3), the temperature of the self-assembly reaction is 45-60℃ and the stirring time is 3-9 hours; preferably, the temperature of the self-assembly reaction is 48-52℃ and the stirring time is 5-7 hours; more preferably, the temperature of the self-assembly reaction is 50℃ and the stirring time is 6 hours.

7. The preparation method according to claim 1 or 2, characterized in that, In step (4), dialysis is performed using a dialysis bag, and the molecular weight cutoff of the dialysis bag is preferably 10-30×10⁻⁶. 4 DA, stirring speed 150-250 rpm, dialysis temperature 10-40℃, room temperature, dialysis time 6-24 h; preferably, the molecular weight cutoff of the dialysis bag is 18-22 × 10⁻⁶. 4 DA, stirring speed 180-220 rpm, dialysis temperature 10-30℃, room temperature, dialysis time 8-16 h; more preferably, the molecular weight cutoff of the dialysis bag is preferably 20 × 10⁻⁶. 4 DA, stirring speed 200 rpm, dialysis temperature 20-25℃, room temperature, dialysis time 10-14h.

8. A magnesium-ethylene glycol tetraacetic acid nanomedicine prepared by the preparation method according to any one of claims 1-7, wherein the nanomedicine is formed by coordination self-assembly of magnesium ions and ethylene glycol tetraacetic acid; preferably, the particle size of the nanomedicine is 50-200 nm; more preferably, the particle size of the nanomedicine is 50-100 nm; most preferably, the particle size of the nanomedicine is 50 nm.

9. A pharmaceutical composition, characterized in that, The invention comprises the magnesium-ethylene glycol tetraacetic acid nanomedicine according to any one of claims 1-8; and a pharmaceutically acceptable carrier.

10. Use of the magnesium-ethylene glycol tetraacetic acid nanomedicine of any one of claims 1-8 or the pharmaceutical composition of claim 9 in the preparation of a medicament for treating radiation dermatitis; preferably, the radiation dermatitis is caused by tumor radiotherapy.

Images