Cerium dioxide nanocube drug-loading material targeting microglia as well as preparation method and application of cerium dioxide nanocube drug-loading material

Abstract

The invention discloses a cerium dioxide nanocube drug-loading material targeting microglial cells and a preparation method and application thereof, and relates to the technical field of biomedical materials.The preparation method comprises the following steps that 1, cerium chloride is added into oleic acid, heating and stirring are conducted, and a cerium oleate compound is obtained; (2) adding the cerium oleate compound into an organic solvent, and heating to obtain CeO2 nanocubes; (3) dissolving the DSPE-PEG-MAL and the MG1 peptide in PBS (Phosphate Buffer Solution), stirring in a dark place, and concentrating to obtain DSPE-PEG-MG1; (4) modifying the surface of the CeO2 nanocube with DSPE-PEG-MG1, so as to obtain CeO2 (at) MG1; and (5) loading the ceftriaxone sodium CFX. The preparation method has the beneficial effects that the prepared CeO2 nanocube drug-loading system realizes active targeting of inflammatory microglia by virtue of MG1, finally remodeling an inflammatory microenvironment, and realizing accurate treatment of allergic rhinitis with olfactory disorder.

Description

Technical Field

[0001] The present invention relates to the technical field of biomedical materials, and in particular to a cerium dioxide nanocube drug-loaded material targeting microglial cells, and a preparation method and application thereof. Background Art

[0002] The emergence of nanomaterials has provided a new opportunity for the treatment of diseases. In recent years, nanomaterials with enzyme-mimicking activity have shown great potential in the research and development of therapeutic drugs. Cerium is a multivalent transition metal element. Cerium-based nanozymes utilize Ce to 3+ and Ce 4+ The unique redox cycle between the two valence states specifically scavenges ROS, exhibiting superoxide dismutase (SOD-like) and catalase (CAT-like) activities, effectively protecting tissues from excessive ROS-induced damage. Xu et al. constructed ultrasmall cerium dioxide (CeO2) nanoparticles (CeO2-MC) loaded with minocycline (MC), which exhibited excellent free radical scavenging ability and significantly reduced neuroinflammation in rats with intracerebral hemorrhage. Chen et al. synthesized ultrasmall cerium-based metal-organic frameworks (MOFs) and demonstrated that Ce-based MOFs effectively alleviate dry eye by inhibiting oxidative stress and inflammatory responses. To address the precise delivery of Ce-based MOFs, Shan et al. camouflaged Ce-based MOFs with mesenchymal stem cell membranes to construct an inflammation-targeting nanomedicine (Ce-UiO-CM), developing a rapid and precise thrombolytic therapy strategy. Compared with traditional free radical scavengers, Ce-based nanomaterials offer advantages such as high efficiency, stability, and reproducibility, and exhibit promising research value and application prospects in regulating and tracking various inflammatory diseases.

[0003] Intranasal drug delivery is a potential non-invasive treatment strategy, in which the olfactory pathway, as a "window to the brain", is an important channel for intranasal drug delivery. In addition, since most nasal drop preparations are not targeted, the "nose-to-brain" delivery efficiency is poor. Therefore, the development of new treatment strategies to solve the problem of precise delivery of nanomaterials to inflammatory microglial cells in the olfactory bulb is an urgent problem to be solved. Especially for inflammatory diseases of the olfactory area, such as allergic rhinitis and olfactory disorders, it is urgent and challenging to improve the nasal "nose-to-olfactory bulb" delivery efficiency of drug preparations and achieve their efficient and specific effect in the olfactory area. However, there are few reports on targeted intranasal drug delivery agents or materials. Summary of the Invention

[0004] The technical problem to be solved by the present invention is how to propose a cerium dioxide nanocube drug-carrying material targeting microglia.

[0005] The present invention solves the above technical problems through the following technical means:

[0006] The first aspect of the present invention provides a method for preparing a microglial-targeting cerium dioxide nanocube drug-loaded material, comprising the following steps:

[0007] (1) mixing cerium chloride and oleic acid and heating them in an oil bath to obtain a cerium oleate complex;

[0008] (2) adding the cerium oleate complex of step (1) to an organic solvent, heating the mixture in an inert gas atmosphere for reaction and purifying the mixture to obtain cerium dioxide nanocubes (CeO2 NCs); the organic solvent is a mixture of 1-octadecene, oleylamine and oleic acid;

[0009] (3) Distearoylphosphatidylethanolamine-polyethylene glycol-maleimide (DSPE-PEG-MAL) and M1 microglia homing peptide (MG1) were dissolved in PBS, stirred in the dark, reacted in an inert gas atmosphere, and then concentrated to obtain DSPE-PEG-MG1;

[0010] (4) The CeO2 NCs obtained in step (2) were dissolved in a dichloromethane solution, and the DSPE-PEG-MG1 obtained in step (3) was added dropwise. The mixture was ultrasonically mixed, rotary evaporated, hydrated, centrifuged, and dispersed in deionized water to obtain CeO2@MG1.

[0011] PBS: Phosphate buffered saline.

[0012] In step (2), 1-octadecene is used as a high boiling point solvent, and oleic acid and oleylamine are used as surfactants.

[0013] Preferably, in step (1), the temperature of the oil bath heating is 95 to 110° C., and the time of the oil bath heating is 1 to 5 hours.

[0014] Preferably, in step (1), the ratio of cerium chloride to oleic acid is 0.1 to 1.0 mmol / mL.

[0015] Preferably, in step (2), the temperature of the heating reaction is 250-290° C., and the heating reaction time is 30 min-2 h.

[0016] Preferably, in step (2), the specific purification process is: cooling the reaction mixture to room temperature, precipitating with acetone, centrifuging and then washing with n-hexane 2 to 3 times, and then centrifuging and washing with anhydrous ethanol 2 to 3 times.

[0017] Preferably, in step (3), the molar ratio of DSPE-PEG-MAL to MG1 is 1.5 to 3:1, and the molecular weight of PEG in DSPE-PEG-MAL is 2000 to 5000.

[0018] Preferably, in step (3), the MG1 is a small molecule linear polypeptide or a derivative having a small molecule polypeptide sequence, and the peptide sequence of the MG1 is C-HHSSSAR-C.

[0019] Preferably, in step (4), the hydration time is 10 to 30 minutes.

[0020] The second aspect of the present invention provides a microglial cell-targeting cerium dioxide nanocube drug-loaded material prepared by the above-mentioned preparation method.

[0021] The third aspect of the present invention proposes the use of the above-mentioned microglial-targeting cerium dioxide nanocube drug-loaded material as a drug carrier.

[0022] Preferably, the drug is mixed with an aqueous solution of CeO2@MG1, shaken for 2 to 6 hours at room temperature in the dark, and centrifuged to obtain a targeted drug targeting microglia.

[0023] Preferably, the concentration ratio of cerium ions to CFX is 1:2 to 16:1.

[0024] Preferably, the drugs include ceftriaxone sodium CFX, glucocorticoid drugs such as dexamethasone, and traditional Chinese medicine small molecule drugs such as tripterygium wilfordii and oleanolic acid.

[0025] Ceftriaxone sodium CFX is a β-lactam antibiotic that can enhance the expression of glutamate transporter-1 (GLT-1) and glutamate uptake, and has a neuroprotective effect.

[0026] The beneficial effects of the present invention are:

[0027] 1. The present invention uses a polypeptide to modify CeO2 NCs and loads ceftriaxone sodium CFX to obtain a targeted drug delivery system CeO2-CFX@MG1. MG1 gives it the ability to actively target inflammatory microglia. CeO2 NCs have excellent free radical scavenging ability and significantly reduce neuroinflammation. CFX can improve amino acid excitotoxicity, synergistically reverse the microglial phenotype, reshape the inflammatory microenvironment, and achieve precise treatment of allergic rhinitis olfactory disorders. This nano drug delivery system can be used as an ideal nasal drop reagent.

[0028] 2. This invention uses cerium chloride as a precursor to synthesize CeO2 NCs in a high-temperature oil-phase solvent. Its ROS-responsive degradation ability facilitates antioxidant activity. This CeO2 nanocube drug delivery system, prepared in this invention, utilizes MG1 to actively target inflammatory microglia, ultimately reshaping the inflammatory microenvironment and enabling precise treatment of allergic rhinitis with olfactory impairment.

[0029] 3. The present invention combines the local drug delivery technology of nanomaterials to prepare a drug delivery system targeting inflammatory microglia, which can improve the efficiency of nose-to-brain delivery and help to achieve precise treatment of olfactory disorders in allergic rhinitis; and the nano drug delivery system has good biosafety, a simple preparation process, relatively low cost, and is easy to produce; the raw materials are environmentally friendly and have no chemical pollution.

[0030] 4. This nanomaterial uses polyethylene glycol to modify the surface of cerium dioxide nanocubes to enhance bioavailability and promote the loading of ceftriaxone sodium (CFX). It covalently grafts the microglia-targeting peptide MG1 to enhance the nose-to-brain delivery efficiency, allowing it to specifically recognize olfactory bulb microglia through the nose-olfactory bulb pathway, reverse the microglial phenotype, reshape the inflammatory microenvironment, and ultimately achieve precise treatment of olfactory disorders in allergic rhinitis. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 TEM image of CeO2 NCs prepared in Example 1 of the present invention;

[0032] Figure 2 is the XRD pattern of CeO2 NCs prepared in Example 1 of the present invention;

[0033] Figure 3 This is the UV-visible spectrum of the CeO2 NCs drug delivery system targeting microglia in Example 2 of the present invention;

[0034] Figure 4 This is a diagram showing the cell biocompatibility of CeO2 NCs on nasal mucosal epithelial cells in Example 3 of the present invention;

[0035] Figure 5 This is a graph showing the antioxidant activity of CeO2 NCs prepared in Example 4 of the present invention;

[0036] Figure 6 This is a comparison chart of the uptake of CeO2 and CeO2-CFX@MG1 of the present invention by microglia detected by flow cytometry in Example 5 of the present invention;

[0037] Figure 7 This is a comparison of the uptake of CeO2 and CeO2-CFX@MG1 of the present invention by microglia observed under a confocal microscope in Example 5 of the present invention;

[0038] Figure 8 for Figure 1 A partial enlarged view of . DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. Unless otherwise defined, the professional terms used below have the same meaning as those understood by professional and technical personnel in this field.

[0040] Unless otherwise specified, the test materials and reagents used in the following examples can be obtained from commercial sources or prepared by known methods.

[0041] If no specific techniques or conditions are specified in the examples, they can be carried out according to the techniques or conditions described in the literature in this field or according to the product instructions. Unless otherwise specified, the quantitative tests in the following examples were repeated three times and the results were averaged.

[0042] Example 1:

[0043] A method for preparing cerium dioxide nanocubes comprises the following steps:

[0044] (1) Add 10 mmol of cerium chloride and 20 ml of oleic acid into a three-necked flask, stir magnetically to mix evenly, and stir in an oil bath at 110°C for 1 h to obtain a light yellow clear liquid, which is the cerium oleate complex.

[0045] (2) Add 10 mL of oleylamine, 10 mL of oleic acid, and 18 mL of 1-octadecene to a three-necked flask and stir the mixture magnetically. Heat the mixture to 100°C for 10 min. Then, under nitrogen, raise the temperature to 290°C and immediately and rapidly inject 2 mmol of the cerium oleate complex prepared in step (1). Continue to heat the mixture at 290°C for 1 h.

[0046] After the reaction is completed, the reaction system is cooled to room temperature under a nitrogen atmosphere, precipitated with acetone and centrifuged, washed three times with n-hexane, centrifuged again and washed three times with anhydrous ethanol to obtain hydrophobic CeO2 NCs, which are then dispersed in dichloromethane.

[0047] The morphology of the hydrophobic CeO2 NCs prepared above was characterized by transmission electron microscopy (TEM). Figure 1 As shown in the TEM, CeO2 NCs have regular morphology, uniform size, and are cubic in shape, about 50nm. Figure 2 As shown, the XRD pattern shows that the sample has strong characteristic peaks, which is consistent with the fluorite structure CeO2 phase (PDF#81-0792).

[0048] Take 5 mg of hydrophobic CeO2 NCs and add excess DSPE-mPEG 2000 Ultrasonic mixing was performed for 5 minutes to ensure uniform mixing. The mixture was evaporated at 40°C using a rotary evaporator under vacuum conditions to remove dichloromethane. Deionized water was added to resuspend the mixture to obtain water-soluble CeO2 NCs.

[0049] Example 2:

[0050] A method for preparing a microglial-targeting cerium dioxide nanocube drug-loaded material comprises the following steps:

[0051] (1) DSPE-PEG 2000 -MAL and MG1 were dissolved in PBS at a molar ratio of 2:1, stirred in the dark, reacted in an argon atmosphere, and concentrated to obtain DSPE-PEG. 2000 -MG1; (PEG molecular weight is 2000, denoted as PEG 2000 )

[0052] The peptide sequence of MG1 is C-HHSSSAR-C;

[0053] (2) The CeO2 NCs obtained in Example 1 were dissolved in dichloromethane solution, and DSPE-PEG was added dropwise. 2000 -MG1, ultrasonically mixed, ultrasonically mixed, and rotary evaporated in a container at 38°C for 20 minutes, hydrated for 15 minutes, centrifuged, and dispersed in deionized water to obtain the microglial cell-targeting cerium dioxide nanocube drug-loaded material CeO2@MG1.

[0054] The above-mentioned CeO2@MG1 was used as a drug carrier to prepare targeted drugs targeting microglia:

[0055] Under ultrasonic conditions, ceftriaxone sodium (CFX) was added dropwise to the CeO2 NCs aqueous solution and shaken overnight at room temperature. Excess CFX was removed by centrifugation to obtain the CFX-loaded CeO2-CFX@MG1 targeted drug. CeO2-CFX was prepared under the same conditions.

[0056] The water-soluble CeO2 NCs and CFX prepared in Example 1, the CeO2-CFX prepared in Example 2, and CeO2-CFX@MG1 were tested. Figure 3 The UV-visible spectrum shows that the CeO2-CFX@MG1 drug delivery system was successfully prepared.

[0057] Example 3:

[0058] The evaluation of the cell biocompatibility of CeO2 NCs prepared in Example 1 on nasal mucosal epithelial cells specifically includes the following steps:

[0059] (1) Culture of microglia

[0060] HNEpC cells were cultured at 10 4 Cells were seeded at a density of 100 cells / well in a 96-well plate and cultured for 12 hours. After 12 hours, cells were incubated with different concentrations of materials and cultured for another 24 hours.

[0061] (2) CCK8 assay to detect the effect of CeO2 NCs on HNEpC cell viability

[0062] Prepare CCK8 detection solution with fresh culture medium, add 110 μL of CCK8 detection solution to each well and continue to culture for 1 hour. After gently shaking, measure the absorbance value at 490 nm.

[0063] like Figure 4 As shown in Figure 3, the CCK8 experimental results showed that CeO2 NCs had no obvious toxicity to HNEpC cells, indicating that CeO2 NCs had good cell biosafety.

[0064] Example 4:

[0065] The antioxidant activity of CeO2 NCs prepared in Example 1 was evaluated, specifically comprising the following steps:

[0066] (1) preparing a 2,2-biphenyl-1-picrylhydrazyl (DPPH) ethanol solution so that its absorbance is between 0.6 and 1.0;

[0067] (2) CeO2 NCs with different concentrations were mixed with DPPH ethanol solution, mixed thoroughly and incubated in the dark to observe the color change.

[0068] like Figure 5 As shown in Figure 3, with the increase of CeO2 NCs concentration, the color of DPPH ethanol solution gradually became lighter, indicating that CeO2 NCs have antioxidant activity.

[0069] Example 5:

[0070] The microglial targeting ability of CeO2-CFX@MG1 prepared in Example 2 was evaluated, specifically comprising the following steps:

[0071] (1) Culture of microglial cells

[0072] BV2 cells and HMC3 cells were cultured at 5×10 4 The cells were seeded at a density of 1 / well in a confocal dish and cultured overnight.

[0073] (2) Flow cytometry detection of microglial uptake of CeO2 and CeO2-CFX@MG1

[0074] CeO2 and CeO2-CFX@MG1 were labeled with fluorescein isothiocyanate (FITC) to obtain CeO2-FITC and CeO2-CFX@MG1-FITC, respectively. Cells were incubated with the same concentrations of CeO2-FITC and CeO2-CFX@MG1-FITC for 4 hours, after which the cells were digested and cellular uptake was analyzed by flow cytometry.

[0075] (3) Laser confocal microscopy observation of microglial uptake of CeO2 and CeO2@MG1

[0076] The cells were incubated with the same concentrations of CeO2-FITC and CeO2-CFX@MG1-FITC for 4 h, then the cells were fixed, the cell nuclei were stained with DAPI, and the cellular uptake was observed using a laser confocal microscope.

[0077] like Figure 6 As shown in the figure, compared with CeO2-FITC at the same concentration, there is a stronger fluorescence signal in the microglia incubated with CeO2-CFX@MG1-FITC, which indicates that the nanomaterial modified with MG1 has microglia targeting ability. Figure 7 The observation results were consistent with those detected by flow cytometry.

[0078] Example 6:

[0079] (1) Add 10 mmol of cerium chloride and 10 ml of oleic acid into a three-necked flask, stir magnetically to mix, and stir in an oil bath at 100°C for 2 h to obtain a light yellow clear liquid, which is the cerium oleate complex.

[0080] (2) 10 mL of oleylamine and 18 mL of 1-octadecene were added to a three-necked flask and stirred magnetically. The mixture was heated to 100°C for 10 min. Under nitrogen protection, the temperature was raised to 290°C and 2 mmol of the cerium oleate complex prepared in step (1) was immediately and rapidly injected. The mixture was then kept at 250°C for 2 h.

[0081] After the reaction is completed, the reaction system is cooled to room temperature under nitrogen atmosphere, precipitated with acetone and centrifuged, and washed three times with cyclohexane to obtain hydrophobic CeO2 NCs.

[0082] Take 5 mg of hydrophobic CeO2 NCs and add excess DSPE-mPEG 2000 Ultrasonication was performed for 5 minutes to mix the mixture uniformly. The mixture was evaporated at 40°C using a rotary evaporator under vacuum conditions to remove dichloromethane. Deionized water was added and resuspended to obtain water-soluble CeO2 NCs.

[0083] (3) DSPE-PEG 5000-MAL and MG1 were dissolved in PBS at a molar ratio of 1.5:1, stirred in the dark, reacted in an argon atmosphere, and then concentrated to obtain DSPE-PEG. 5000 -MG1; (PEG molecular weight is 5000, denoted as PEG 5000 )

[0084] The peptide sequence of MG1 is C-HHSSSAR-C;

[0085] (4) Dissolve the CeO2 NCs obtained in (2) in dichloromethane solution and add DSPE-PEG 2000 -MG1, ultrasonically mixed, ultrasonically mixed, and rotary evaporated in a container at 38°C for 20 minutes, hydrated for 30 minutes, centrifuged, and dispersed in deionized water to obtain the microglial cell-targeting cerium dioxide nanocube drug-loaded material CeO2@MG1.

[0086] Example 7:

[0087] (1) Add 10 mmol of cerium chloride and 100 ml of oleic acid into a three-necked flask, stir the mixture by magnetic stirring, and stir in an oil bath at 95°C for 5 h to obtain a light yellow clear liquid, which is the cerium oleate complex.

[0088] (2) 10 mL of oleylamine and 18 mL of 1-octadecene were added to a three-necked flask and stirred magnetically. The mixture was heated to 100°C for 10 min. Under nitrogen protection, the temperature was raised to 290°C and 2 mmol of the cerium oleate complex prepared in step (1) was immediately and rapidly injected. The mixture was then kept at 260°C for 30 min.

[0089] After the reaction is completed, the reaction system is cooled to room temperature under nitrogen atmosphere, precipitated with acetone and centrifuged, and washed three times with cyclohexane to obtain hydrophobic CeO2 NCs.

[0090] Take 5 mg of hydrophobic CeO2 NCs and add excess DSPE-mPEG 2000 Ultrasonication was performed for 5 minutes to mix the mixture uniformly. The mixture was evaporated at 40°C using a rotary evaporator under vacuum conditions to remove dichloromethane. Deionized water was added and resuspended to obtain water-soluble CeO2 NCs.

[0091] (3) DSPE-PEG 3000 -MAL and MG1 were dissolved in PBS at a molar ratio of 3:1, stirred in the dark, reacted in an argon atmosphere, and concentrated to obtain DSPE-PEG. 3000 -MG1; (PEG molecular weight is 3000, denoted as PEG 3000 )

[0092] The peptide sequence of MG1 is C-HHSSSAR-C;

[0093] (4) Dissolve the CeO2 NCs obtained in (2) in dichloromethane solution and add DSPE-PEG 2000 -MG1, ultrasonically mixed, ultrasonically mixed, and rotary evaporated in a container at 38°C for 20 minutes, hydrated for 10 minutes, centrifuged, and dispersed in deionized water to obtain the microglial cell-targeting cerium dioxide nanocube drug-loaded material CeO2@MG1.

[0094] Comparative Example 1:

[0095] The difference between this comparative example and Example 1 is that the organic solvent in step (2) is only 1-octadecene, and the rest is the same as Example 1.

[0096] Results: Cerium dioxide nanocubes (CeO2 NCs) could not be prepared.

[0097] Comparative Example 2:

[0098] The difference between this comparative example and Example 1 is that the organic solvent in step (2) is only oleylamine, and the rest is the same as Example 1.

[0099] Results: Cerium dioxide nanocubes (CeO2 NCs) could not be prepared.

[0100] Comparative Example 3:

[0101] The difference between this comparative example and Example 1 is that the organic solvent in step (2) is only a mixture of oleylamine and oleic acid, and the rest is the same as Example 1.

[0102] Results: Cerium dioxide nanocubes (CeO2 NCs) could not be prepared.

[0103] Comparative Example 4:

[0104] The difference between this comparative example and Example 1 is that the organic solvent in step (2) is only a mixture of 1-octadecene and oleic acid, and the rest is the same as Example 1.

[0105] Results: Cerium dioxide nanocubes (CeO2 NCs) could not be prepared.

[0106] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for preparing a cerium dioxide nanocube drug-loaded material targeting microglia, characterized in that: The following steps are involved: (1) mixing cerium chloride and oleic acid and heating them in an oil bath to obtain a cerium oleate complex; (2) adding the cerium oleate complex of step (1) to an organic solvent, heating the mixture in an inert gas atmosphere for reaction and purifying the mixture to obtain cerium dioxide nanocubes (CeO2 NCs); the organic solvent is a mixture of 1-octadecene, oleylamine and oleic acid; (3) Distearoylphosphatidylethanolamine-polyethylene glycol-maleimide (DSPE-PEG-MAL) and M1 microglia homing peptide (MG1) were dissolved in PBS, stirred in the dark, reacted in an inert gas atmosphere, and then concentrated to obtain DSPE-PEG-MG1; (4) The CeO2 NCs obtained in step (2) were dissolved in a dichloromethane solution, and the DSPE-PEG-MG1 obtained in step (3) was added dropwise. The mixture was ultrasonically mixed, rotary evaporated, hydrated, centrifuged, and dispersed in deionized water to obtain CeO2@MG1.

2. The preparation method according to claim 1, characterized in that In step (1), the temperature of the oil bath heating is 95 to 110° C., and the time of the oil bath heating is 1 to 5 hours.

3. The preparation method according to claim 1, characterized in that In step (1), the usage ratio of cerium chloride to oleic acid is 0.1-1.0 mmol / mL.

4. The preparation method according to claim 1, characterized in that In step (2), the heating reaction temperature is 250-290° C., and the heating reaction time is 30 min-2 h.

5. The preparation method according to claim 1, characterized in that In step (2), the specific purification process is as follows: the mixed solution after the reaction is cooled to room temperature, precipitated with acetone, centrifuged and then washed with n-hexane 2 to 3 times, and then centrifuged and washed with anhydrous ethanol 2 to 3 times.

6. The preparation method according to claim 1, characterized in that In step (3), the molar ratio of DSPE-PEG-MAL to MG1 is 1.5 to 3:1, and the molecular weight of PEG in DSPE-PEG-MAL is 2000 to 5000.

7. The preparation method according to claim 1, characterized in that In step (4), the hydration time is 10 to 30 minutes.

8. The microglial cell-targeting cerium dioxide nanocube drug-loaded material obtained by the preparation method according to any one of claims 1 to 7.

9. Use of the microglial cell-targeting cerium dioxide nanocube drug-loaded material according to claim 8 as a drug carrier.

10. The use according to claim 9, characterized in that The drug is mixed with an aqueous solution of CeO2@MG1, shaken for 2 to 6 hours at room temperature in the dark, and centrifuged to obtain a targeted drug targeting microglia.

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