A hydrophilic polymer-coated magnetic nanomaterial based on a hilic strategy and a preparation method and application thereof

Abstract

The application provides a preparation method of a hydrophilic polymer-coated magnetic nanomaterial based on a HILIC strategy, and comprises the following steps: S1, preparing Fe3O4 by a hot solvent method; S2, polymerizing N,N-methylene bisacrylamide and 1,2-epoxy-5-hexene as ligands on the surface of the Fe3O4 obtained in the step S1; S3, grafting 2-aminopurine on the surface of the product obtained in the step S2 through an epoxy ring-opening reaction; and S4, washing and drying the product obtained in the step S3 to obtain the hydrophilic polymer-coated magnetic nanomaterial based on the HILIC strategy. The application also includes the magnetic nanomaterial and the application thereof in mass spectrometry detection and serum exosome separation. The novel hydrophilic polymer-coated magnetic nanomaterial based on the HILIC strategy prepared by the application has the advantages of simple operation, short time consumption, accurate detection result, good specificity and good application prospect in mass spectrometry detection and exosome separation.

Description

Technical Field

[0001] This invention relates to the field of magnetic nanomaterials, and more specifically, to a hydrophilic polymer-coated magnetic nanomaterial based on the HILIC strategy, its preparation method, and its application. Background Technology

[0002] Exosomes, secreted by cells, are complex membrane vesicles containing RNA, lipids, and proteins. These specialized membrane vesicles are naturally present in various body fluids and are believed to participate in physiological responses such as intercellular communication, signal transduction, and immune regulation. With the deepening of exosome research, evidence suggests that exosomes participate in the pathological processes of various diseases and even serve as important biomarkers for some diseases, potentially enabling their early detection. To better utilize these unique characteristics of exosomes for disease diagnosis and treatment, the isolation and capture of exosomes from biological samples is crucial. Ultracentrifugation is a relatively traditional separation method, but it suffers from problems such as cumbersome operation, long processing time, and low efficiency. Therefore, methods for separating exosomes from samples still need further improvement, necessitating the exploration of innovative, low-cost, and efficient methods for separating and capturing exosomes.

[0003] Glycosylation is one of the most important and abundant post-translational modifications of proteins. It plays an irreplaceable role in organisms, participating in numerous biological processes such as cell adhesion, signal transduction, intercellular communication, protein degradation, and immune protection. Therefore, the quantitative and qualitative analysis of glycopeptides is crucial for the detection and identification of clinicopathological biomarkers. To date, many methods for selectively enriching glycopeptides have been explored. Among them, hydrophilic interaction liquid chromatography (HILIC) is increasingly favored due to its advantages of high coverage, simple operation, good reproducibility, good mass spectrometry compatibility, and low cost. However, traditional HILIC materials often suffer from low glycopeptide binding capacity and low detection sensitivity due to the relatively low density of hydrophilic molecules. Therefore, it is necessary to prepare materials with higher hydrophilicity to increase the retention of glycopeptides.

[0004] In recent years, polymer-modified HILIC materials have attracted considerable attention. The high density of repeating groups on the polymer surface provides numerous binding sites. Furthermore, the flexible polymer chains can form favorable spatial conformations, which significantly improve the binding efficiency of HILIC materials to glycopeptides.

[0005] However, the current system for preparing hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy is not yet perfect, the preparation methods are relatively complex, and there is no mature system for the application of the prepared magnetic nanomaterials. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a method for preparing hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy, so as to fill the technical gap in this field and provide a simple preparation method.

[0007] To address the above problems, this invention provides a method for preparing hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy, comprising the following steps:

[0008] S1: Fe3O4 was prepared by a hot solvent method;

[0009] S2: Using N,N-methylenebisacrylamide and 1,2-epoxy-5-hexene as ligands, polymerize on the surface of Fe3O4 obtained in step S1;

[0010] S3: Grafting 2-aminopurine onto the surface of the product obtained in step S2 via an epoxy ring-opening reaction;

[0011] S4: Wash and dry the product obtained in step S3 to obtain a magnetic nanomaterial coated with a hydrophilic polymer based on the HILIC strategy.

[0012] As a preferred embodiment, in step S2, the mass ratio of Fe3O4, N,N-methylenebisacrylamide, and 1,2-epoxy-5-hexene is 1:0.67:(0.4-0.5).

[0013] By combining the above-mentioned raw materials, the microstructure and size of novel hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy can be better adjusted.

[0014] As a preferred embodiment, the reaction temperature in step S2 is 80°C and the reaction time is 4 hours.

[0015] As a preferred embodiment, the reaction temperature in step S3 is 80°C and the reaction time is 4 hours.

[0016] As a preferred embodiment, in step S4, the washing conditions are deionized water and ethanol, and the drying is vacuum drying.

[0017] The present invention provides a method for preparing hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy. By optimizing the reaction time and raw material concentration, the microstructure and size of the novel hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy can be adjusted, thereby obtaining materials with optimal performance and greatly improving the ability to enrich glycopeptides.

[0018] One of the technical problems to be solved by the present invention is to provide a hydrophilic polymer-coated magnetic nanomaterial based on the HILIC strategy to solve the problem of low relative density of conventional magnetic nanomaterials.

[0019] To address the aforementioned issues, this invention also discloses a hydrophilic polymer-coated magnetic nanomaterial based on the HILIC strategy, wherein the magnetic nanomaterial is prepared by the aforementioned preparation method.

[0020] One of the technical problems to be solved by the present invention is to provide the application of the novel hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy in mass spectrometry detection.

[0021] To address the aforementioned issues, this invention also discloses the application of the novel hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy. The application includes the use of the magnetic nanomaterials in mass spectrometry detection, specifically: using the magnetic nanomaterials for the selective enrichment of glycosylated peptides.

[0022] As a preferred embodiment, the application includes: dispersing novel hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy into 100 μL of a centrifuge tube containing glycosylated peptides, 1% (v / v) trifluoroacetic acid, and 90% (v / v) acetonitrile, and enriching at 37 °C for 1 min; then thoroughly washing with a buffer solution of 1% (v / v) trifluoroacetic acid and 90% (v / v) acetonitrile, and magnetically separating; then eluting with a buffer solution of 0.1% (v / v) trifluoroacetic acid and 30% (v / v) acetonitrile for 1 min, taking 1 μL of the eluent for target spotting, and performing MALDI TOF MS mass spectrometry analysis.

[0023] One of the technical problems to be solved by the present invention is to provide the application of the novel hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy in the separation of serum exosomes.

[0024] To address the aforementioned issues, this invention also discloses an application of the novel hydrophilic polymer-coated magnetic nanomaterial based on the HILIC strategy, the application of which includes the use of the magnetic nanomaterial in serum exosome separation, comprising: using the magnetic nanomaterial to capture and separate exosomes.

[0025] As a preferred embodiment, the application includes: dispersing novel hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy into a 100 μL centrifuge tube containing serum, enriching at 4°C for 1 min, and then washing thoroughly with PBS solution; then eluting with 20 μL of a buffer solution containing 0.1% trifluoroacetic acid and 30% acetonitrile for 1 min, and performing relevant analysis on the resulting eluent.

[0026] The novel hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy prepared in this invention are simple to operate, time-saving, accurate and specific in mass spectrometry detection and exosome separation applications, and have good application prospects. Attached Figure Description

[0027] Figure 1 Scanning electron microscope image of the novel hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy prepared in Example 1;

[0028] Figure 2 The infrared spectrum of the novel hydrophilic polymer-coated magnetic nanomaterial based on the HILIC strategy prepared in Example 1 is shown.

[0029] Figure 3 This is a mass spectrum of HRP-enriched glycopeptides in a novel hydrophilic polymer-coated magnetic nanomaterial based on the HILIC strategy, as described in Example 3; (* represents glycosylated peptides).

[0030] Figure 4 The mass spectrum of the novel hydrophilic polymer-coated magnetic nanomaterial based on the HILIC strategy in Example 3 shows the detection limit (0.01 fmol / μL) of enriched glycosylated peptides (* represents glycosylated peptides).

[0031] Figure 5 This is a mass spectrum of glycopeptides enriched in a mixed protein (non-glycosylated protein BSA: glycosylated protein HRP = 1000: 1) using a novel hydrophilic polymer-coated magnetic nanomaterial based on the HILIC strategy in Example 4 (* represents glycosylated peptides).

[0032] Figure 6 Example 5 illustrates the enrichment of glycosylated peptides (* represents glycosylated peptides) in human saliva using novel hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy.

[0033] Figure 7 This is a transmission electron microscope image of a novel hydrophilic polymer-coated magnetic nanomaterial based on the HILIC strategy used in Example 6 to capture serum exosomes. Detailed Implementation

[0034] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0035] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0036] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0037] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be readily apparent to those skilled in the art. This application specification and embodiments are merely exemplary.

[0038] This invention discloses a method for preparing hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy, comprising the following steps:

[0039] S1: Fe3O4 was prepared by a hot solvent method;

[0040] S2: Using N,N-methylenebisacrylamide and 1,2-epoxy-5-hexene as ligands, polymerize on the surface of Fe3O4 obtained in step S1;

[0041] S3: Grafting 2-aminopurine onto the surface of the product obtained in step S2 via an epoxy ring-opening reaction;

[0042] S4: Wash and dry the product obtained in step S3 to obtain a magnetic nanomaterial coated with a hydrophilic polymer based on the HILIC strategy.

[0043] Preferably, in step S2, the mass ratio of Fe3O4, N,N-methylenebisacrylamide, and 1,2-epoxy-5-hexene is 1:0.67:(0.4-0.5).

[0044] Preferably, the reaction temperature in step S2 is 80°C and the reaction time is 4 hours.

[0045] Preferably, the reaction temperature in step S3 is 80°C and the reaction time is 4 hours.

[0046] Preferably, in step S4, the washing conditions are deionized water and ethanol, and the drying is vacuum drying.

[0047] The present invention also discloses a hydrophilic polymer-coated magnetic nanomaterial based on the HILIC strategy, wherein the magnetic nanomaterial is prepared by the preparation method described above.

[0048] This invention also discloses the application of the novel hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy, including the application of the magnetic nanomaterials in mass spectrometry detection, specifically using the magnetic nanomaterials for the selective enrichment of glycosylated peptides.

[0049] Preferably, the application includes: dispersing novel hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy into 100 μL of a centrifuge tube containing glycosylated peptides, 1% (v / v) trifluoroacetic acid, and 90% (v / v) acetonitrile, and enriching at 37°C for 1 min; then washing thoroughly with a buffer solution of 1% (v / v) trifluoroacetic acid and 90% (v / v) acetonitrile, and magnetically separating; then eluting with a buffer solution of 0.1% (v / v) trifluoroacetic acid and 30% (v / v) acetonitrile for 1 min, taking 1 μL of the eluent for target spotting, and performing MALDI TOF MS mass spectrometry analysis.

[0050] The present invention also discloses an application of the novel hydrophilic polymer-coated magnetic nanomaterial based on the HILIC strategy, the application of which includes the application of the magnetic nanomaterial in serum exosome separation, comprising: using the magnetic nanomaterial to capture and separate exosomes.

[0051] Preferably, the application includes: dispersing novel hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy into a 100 μL centrifuge tube containing serum, enriching at 4°C for 1 min, and then washing thoroughly with PBS solution; then eluting with 20 μL of a buffer solution containing 0.1% trifluoroacetic acid and 30% acetonitrile for 1 min, and performing relevant analysis on the resulting eluent.

[0052] The technical solution of the present invention will be described in detail below with reference to specific data:

[0053] Example 1

[0054] The preparation of novel hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy includes the following steps:

[0055] S1. Fe3O4 was prepared by solvothermal method.

[0056] S2. Add 30 mg Fe3O4 and 20 mg N,N-methylenebisacrylamide to 1 mL of ethanol, then add 15 μL of 1,2-epoxy-5-hexene and 2 mg of initiator azobisisobutyronitrile (AIBN), and shake at 80 °C for 4 h; wash the obtained product with ethanol and deionized water, and dry it overnight in a vacuum desiccator at 60 °C.

[0057] S3. Add the product obtained in step S3 to 1 mL of deionized water containing 2-aminopurine (35 mg), shake at 80 °C for 4 hours, wash thoroughly with deionized water and ethanol, and dry in a vacuum dryer at 50 °C for 24 hours. This yields a novel hydrophilic polymer-coated magnetic nanomaterial based on the HILIC strategy.

[0058] Scanning electron microscope (SEM) images of the novel hydrophilic polymer-coated magnetic nanomaterials prepared based on the HILIC strategy (20 kV, ZEISS Sigma 300 electron microscope, Germany) are shown below. Figure 1 As shown, the SEM image reveals that the final product is a sphere of uniform size and rough surface. The Fourier transform infrared spectrum (Thermo Fisher Scientific NIcoleti S10, USA) is shown below. Figure 2 As shown, at 1653cm -1 and 1535cm -1 The peaks observed at 881 cm⁻¹ correspond to the stretching vibrations of C=O and NH in imino groups, respectively. Furthermore, at 881 cm⁻¹... -1 1050cm -1 and 1090cm -1 The three peaks observed at 592 cm⁻¹ are attributed to the absorption of epoxy groups. All materials show peaks at 592 cm⁻¹. -1 A peak appears at [value missing], which is a characteristic peak of Fe-O. After the ring-opening reaction of the epoxy-amino group, the peak reaches 881 cm⁻¹. -1 and 1050cm -1 The disappearance of the peak at the point indicates that most of the epoxy groups were consumed, proving that 2-aminopurine was successfully modified on the material surface.

[0059] Example 2:

[0060] Example 2 is similar to Example 1, except that in step S2, the amount of 1,2-epoxy-5-hexene added is 12 μL.

[0061] The following describes the practical application of the novel hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy prepared in Example 1:

[0062] Example 3

[0063] The application of novel hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy for enriching glycosylated peptides in horseradish peroxidase (HRP) includes the following steps:

[0064] (1) Sample preparation: HRP (horseradish peroxidase) was enzymatically hydrolyzed in 50mM NH4HCO3 solution at 37℃ for 16h.

[0065] (2) Enrichment: 0.5 mg of the novel hydrophilic polymer-coated magnetic nanomaterial based on the HILIC strategy obtained in Example 1 was dispersed into a centrifuge tube containing 100 μL of 1% trifluoroacetic acid and 90% acetonitrile by volume, and then 2 μL of the sample prepared in step (1) was added. The mixture was enriched at 37 °C for 1 min. The mixture was washed and separated 3 times with a buffer solution containing 1% trifluoroacetic acid and 90% acetonitrile by volume. The mixture was eluted with 10 μL of a buffer solution containing 0.1% trifluoroacetic acid and 30% acetonitrile by volume for 1 min, and the eluent was obtained.

[0066] (3) Mass spectrometry analysis: Take 1 μL of the eluent obtained in step (2) and spot it onto the target. Use DHB as the matrix for mass spectrometry analysis. The mass spectrum is shown below. Figure 3 As shown, adding 2 μL of HRP for enrichment resulted in the capture of 25 peaks belonging to glycopeptides. To further explore the detection limit performance of the material for glycopeptides, the concentration of HRP was varied in the experiment. Figure 4 The novel hydrophilic polymer-coated magnetic nanomaterial based on the HILIC strategy achieves a detection limit (0.01 fmol / μL) for enriching glycosylated peptides in HRP, meaning that seven peaks belonging to glycopeptides can still be detected even at an HRP concentration of 0.01 fmol / μL. This experimental result demonstrates that the synthesized material exhibits excellent enrichment ability and affinity for glycopeptides.

[0067] Example 4

[0068] The application of novel hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy in enriching glycosylated peptides in mixed proteins includes the following steps:

[0069] (1) Sample preparation: Bovine serum albumin (BSA) was first reduced and alkylated with dithiothreitol and iodoacetamide, and then enzymatically digested at 37°C for 16 h; HRP was enzymatically digested in 50 mM NH4HCO3 solution at 37°C for 16 h; Bovine serum albumin (BSA) and HRP were added to centrifuge tubes containing 1% trifluoroacetic acid and 90% acetonitrile at a molar ratio of 1000:1.

[0070] (2) Enrichment: 0.5 mg of the novel hydrophilic polymer-coated magnetic nanomaterial based on the HILIC strategy obtained in Example 1 was dispersed into a centrifuge tube containing 100 μL of 1% trifluoroacetic acid and 90% acetonitrile by volume, and then 2 μL of the sample prepared in step (1) was added. The mixture was enriched at 37 °C for 1 min. The mixture was washed and separated 3 times with a buffer solution containing 1% trifluoroacetic acid and 90% acetonitrile by volume. The mixture was eluted with 10 μL of a buffer solution containing 0.1% trifluoroacetic acid and 30% acetonitrile by volume for 1 min, and the supernatant was obtained.

[0071] (3) Mass spectrometry analysis: Take 1 μL of the eluent obtained in step (2) and spot the target. Use DHB as the matrix for mass spectrometry analysis. The mass spectrum of glycosylated peptides in the mixed protein (non-glycosylated protein BSA: glycosylated protein HRP = 1000:1) enriched by the novel hydrophilic polymer-coated magnetic nanomaterial based on the HILIC strategy is shown in the figure. Figure 5 As shown, the novel hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy can still capture signals from peptides belonging to glycosylated proteins in the presence of interfering proteins, demonstrating the material's excellent selectivity for glycopeptides.

[0072] Example 5

[0073] The application of novel hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy for enriching glycosylated peptides in human saliva includes the following steps:

[0074] (1) Sample preparation: The obtained human saliva (2 mL) was added to 0.2% TFA, and then the supernatant was collected by centrifugation at 8000 rpm for 10 min at 0 °C and stored at -20 °C.

[0075] (2) Enrichment: 0.5 mg of the novel hydrophilic polymer-coated magnetic nanomaterial based on the HILIC strategy obtained in Example 1 was dispersed into 200 μL of centrifuge tube containing 1% v / v trifluoroacetic acid and 90% v / v acetonitrile of the glycosylated peptide from step (1), and enriched at 37°C for 1 min; washed and separated 3 times with buffer of 1% v / v trifluoroacetic acid and 90% v / v acetonitrile; eluted with 10 μL of buffer of 0.1% v / v trifluoroacetic acid and 30% v / v acetonitrile for 1 min.

[0076] (3) Mass spectrometry analysis: Take 1 μL of the eluent obtained in step (2) and spot it onto the target. Use DHB as the matrix for mass spectrometry analysis. The mass spectrum is shown below. Figure 6 As shown, human saliva was selected as the actual sample to verify whether the material can analyze complex biological samples. After enrichment, 42 glycopeptide peaks were captured in human saliva, indicating that the material has great potential for practical applications.

[0077] Example 6

[0078] The application of novel hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy in the capture and separation of exosomes includes the following steps:

[0079] (1) Sample preparation: Dilute the serum sample with an equal volume of PBS buffer solution to reduce viscosity; then centrifuge the diluted serum sample at 3000×g for 3 minutes at 4℃; transfer the supernatant to a centrifuge tube and centrifuge at 12000×g for 45 minutes at 4℃; filter the supernatant through a 0.22μm filter; then centrifuge the filtrate at 110000×g for 2 hours at 4℃ to obtain pure exosomes; finally, redissolve the purified exosomes in PBS and store at -80℃.

[0080] (2) Enrichment: 100 μL of serum was added to 3 mg of the novel hydrophilic polymer-coated magnetic nanomaterial based on the HILIC strategy obtained in Example 1; the mixture was shaken at 4 °C for 1 min; it was washed thoroughly with PBS solution, and finally eluted with 20 μL of a buffer solution of 0.1% v / v trifluoroacetic acid and 30% v / v acetonitrile for 1 min; the transmission electron microscope image of the composite material capturing serum exosomes is shown below. Figure 7 As shown, the TEM image reveals that the exosomes are vesicles with a diameter of approximately 60 nm, which is consistent with previous reports and demonstrates the successful capture and separation of exosomes by the material.

[0081] The above embodiments further demonstrate that the preparation method of hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy of the present invention can adjust the microstructure and size of the novel hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy by optimizing the reaction time and raw material concentration, thereby obtaining materials with optimal performance and greatly improving the ability to enrich glycopeptides.

[0082] Furthermore, the hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy prepared in this invention can achieve good results in the selective enrichment of glycosylated peptides and the separation of serum exosomes, which further proves that the application of this invention solves the technical problems existing in the prior art.

[0083] While the disclosure is as stated above, its scope of protection is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of this disclosure, and all such changes and modifications will fall within the protection scope of this invention.

Claims

1. A method for preparing hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy, characterized in that: Includes the following steps: S1: Fe3O4 was prepared by a hot solvent method; S2: Using N,N-methylenebisacrylamide and 1,2-epoxy-5-hexene as ligands, polymerize on the surface of Fe3O4 obtained in step S1; S3: Grafting 2-aminopurine onto the surface of the product obtained in step S2 via an epoxy ring-opening reaction; S4: Wash and dry the product obtained in step S3 to obtain a magnetic nanomaterial coated with a hydrophilic polymer based on the HILIC strategy.

2. The method for preparing hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy according to claim 1, characterized in that: In step S2, the mass ratio of Fe3O4, N,N-methylenebisacrylamide, and 1,2-epoxy-5-hexene is 1:0.67:(0.4-0.5).

3. The method for preparing hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy according to claim 1, characterized in that: In step S2, the reaction temperature is 80 °C and the reaction time is 4 h.

4. The method for preparing hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy according to claim 1, characterized in that: The epoxy ring-opening reaction in step S3 is carried out at a temperature of 80 °C for 4 h.

5. The method for preparing hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy according to claim 1, characterized in that: In step S4, the washing conditions are deionized water and ethanol, and the drying is vacuum drying.

6. A hydrophilic polymer-coated magnetic nanomaterial based on the HILIC strategy, characterized in that: The magnetic nanomaterial is prepared by any one of the preparation methods of claims 1-5.

7. An application of the hydrophilic polymer-coated magnetic nanomaterial based on the HILIC strategy as described in claim 6, characterized in that, The applications include the use of the magnetic nanomaterials in mass spectrometry detection, including: using the magnetic nanomaterials for selective enrichment of glycosylated peptides.

8. The application according to claim 7, characterized in that, The application includes: dispersing HILIC-based hydrophilic polymer-coated magnetic nanomaterials into 100 μL centrifuge tubes containing glycosylated peptides, 1% (v / v) trifluoroacetic acid, and 90% (v / v) acetonitrile, and enriching at 37 °C for 1 min; then washing thoroughly with a buffer solution of 1% (v / v) trifluoroacetic acid and 90% (v / v) acetonitrile, and magnetically separating; then eluting with a buffer solution of 0.1% (v / v) trifluoroacetic acid and 30% (v / v) acetonitrile for 1 min, taking 1 μL of the eluent for target spotting, and performing MALDI TOF MS mass spectrometry analysis.

9. An application of the hydrophilic polymer-coated magnetic nanomaterial based on the HILIC strategy as described in claim 6, characterized in that, The application includes the use of the magnetic nanomaterial in serum exosome separation, including: using the magnetic nanomaterial to capture and separate exosomes.

10. The application according to claim 9, characterized in that, The application includes: dispersing hydrophilic polymer-coated magnetic nanomaterials based on the HILIC strategy into 100 μL centrifuge tubes containing serum, enriching at 4°C for 1 min, and then washing thoroughly with PBS solution; then eluting with 20 μL of a buffer solution of 0.1% trifluoroacetic acid and 30% acetonitrile for 1 min, and performing transmission electron microscopy analysis on the resulting eluent.

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