Nano-platform for multi-cell targeting and multi-drug delivery of inflammation-related diseases and preparation method of nano-platform

Abstract

The invention belongs to the technical field of pharmaceutical preparations, and relates to a multi-cell targeting and multi-drug delivery nano-platform aiming at inflammation-related diseases and a preparation method of the multi-cell targeting and multi-drug delivery nano-platform. The nano platform comprises an inflammation response core polydopamine, a delivered drug, a synthesized polymer skeleton and other pharmaceutically acceptable auxiliary materials. The preparation method comprises the following steps: forming polydopamine through oxidative auto-polymerization, synthesizing a drug-loading polymer covalently linked with a drug, mixing, self-assembling to form nanoparticles, and adding a cross-linking agent for enhancing stability to finally prepare the nano platform. The prepared nano platform is good in solubility, strong in stability and high in targeting delivery efficiency, and can effectively perform multi-cell multi-drug targeting delivery for inflammation-related diseases.

Description

Technical Field

[0001] The present invention belongs to the technical field of pharmaceutical preparations, and relates to a nano-platform for multi-cell targeting and multi-drug delivery of inflammation-related diseases and a preparation method thereof. Background Art

[0002] According to records, Alzheimer's disease (AD) is a chronic neurodegenerative disease, and there is currently no effective treatment to prevent or stop its progression. Practice shows that early diagnosis of AD is difficult, and most patients only show clinical symptoms in the middle and late stages. Although the pathogenesis of the disease is still unclear, glial cells, the most abundant brain cells, have become a key marker for the pathogenesis of AD. Studies have shown that in the late stage of AD, under long-term exposure to amyloid beta (Aβ), microglia undergo metabolic reprogramming, and their metabolic phenotype changes from oxidative phosphorylation to glycolysis. This process depends on the mTOR-HIF-1α pathway. As a result, microglia enter a chronic tolerance state, with extensive metabolic defects and weakened immune responses; at the same time, astrocytes are overactivated under the stimulation of microglia, secrete proinflammatory factors and increase stem cell-related properties, thereby exacerbating neural damage. Therefore, simultaneous targeted glial cell delivery of drugs is considered by the field to be an effective strategy for treating late AD. However, considering that the physical properties of therapeutic drugs for different targets are different, it is a huge challenge to deliver drugs to different cells in a certain proportion.

[0003] Combination therapy holds exciting promise in targeted disease treatment, where two or more drugs act on cells simultaneously in a certain ratio to enhance synergistic therapeutic effects. However, the clinical translation of this strategy is still hampered by fundamental challenges. Due to the different physical properties of different drugs, such as molecular weight, solubility, and stability, it is difficult for them to maintain consistent biological behavior in vivo. How to deliver drugs of different properties to the lesion site simultaneously in a certain ratio, so that they are taken up by the same or different cells and released on demand, is a key difficulty in the clinical translation of combination therapy. Although it is still unclear whether multidrug carriers have fundamental advantages over single-drug carrier mixtures, related studies have provided evidence for the in vivo therapeutic effects in preclinical animal models.

[0004] Based on the current status of the prior art, the inventors of the present application intend to provide a nanoplatform for multi-cell targeting and multi-drug delivery for inflammatory-related diseases and a preparation method thereof. Summary of the invention

[0005] The purpose of the present invention is to provide a modularly designed nano-platform based on the current state of the art, which can replace the corresponding functional modules according to the different pathological characteristics of the disease, thereby overcoming the obstacles of combined treatment. In the context of late AD, hydroxychloroquine (HCQ) and all-trans retinoic acid (ATRA) can be used as drugs for activating immunity and inducing differentiation, respectively. The drugs are connected to the polymer backbone (abbreviated as D-PPA and A-PPH) through ester bonds to ensure the stability and consistency of in vitro and in vivo behavior. In addition, the targeting peptide on the drug coupling module is modified by polyethylene glycol (PEG) to achieve physiological barrier crossing and cellular internalization. In order to achieve multi-drug delivery and multi-cell targeting, the present invention synthesizes a polydopamine (PDA) nano-core module, which can be decomposed in the oxidative stress microenvironment of the AD brain, and sensitively releases the drug-loaded module to further target glial cells. The drug-loaded module and the nano-core module can be self-assembled into DA-PPHA@PDA by electrostatic adsorption. Then, a ROS-sensitive cross-linker is incorporated into the nano-platform to improve the stability of the system, thereby obtaining DA-PPHA TK @PDA nanoplatform. After intravenous injection, DA-PPHA TK @PDA can actively target CTGF receptors and RAGE highly expressed in endothelial cells under AD conditions and cross the blood-brain barrier (BBB) ​​through transcytosis. HCQ is delivered to microglia to activate immune responses and restore energy metabolism. ATRA is delivered to astrocytes to promote transdifferentiation into functional neurons and reduce inflammation. Finally, the glial cell-targeted regulatory strategy can reduce Aβ plaques and neuronal loss and rescue cognitive impairment in APP / PS1 transgenic model mice. The present invention designs an effective glial regulatory strategy for the treatment of advanced AD and proposes a universal multicellular targeted nanoplatform for the targeted treatment of AD and other inflammatory-related diseases.

[0006] Specifically, the present invention provides a nano-platform for multi-cell targeting and multi-drug delivery for inflammation-related diseases and a preparation method thereof. The nano-platform comprises a therapeutic drug, a synthetic polymer skeleton, a synthetic polydopamine nano-core, a ROS-sensitive cross-linking agent and other pharmaceutically acceptable excipients. The particle size of the nano-platform is about 70 nm.

[0007] In the present invention, the loaded drugs are all-trans retinoic acid and hydroxychloroquine.

[0008] In the present invention, the drug-carrying polymer skeleton is PEG, polyallylamine (molecular weight of about 15,000) and ROS-sensitive bond TK-linker connected to the targeting polypeptide.

[0009] In the present invention, the targeting polypeptide can bind to the RAGE receptor highly expressed in AD cerebral blood vessels and microglia, and the Ab polypeptide sequence is KLVFFAED. And the targeting polypeptide can bind to the CTGF receptor highly expressed in cerebral blood vessels and astrocytes, and the DAG polypeptide sequence is a cyclic peptide (CDGRKQKC).

[0010] More specifically, the present invention provides a method for synthesizing a universal drug-carrying polymer, comprising the following steps:

[0011] Synthesis of ATRA-loaded D-PPA polymer:

[0012] (1) Dissolve 200 mg ATRA, 34.39 mg ethylene glycol, 67.77 mg DMAP and 106.3 mg EDC in 5 ml dichloromethane. The reaction system is stirred at room temperature for about 10 hours under the protection of nitrogen. Add an appropriate amount of 400 mesh silica gel powder to the reaction solution and evaporate it to dryness. The spin-dried silica gel is loaded into a column and separated by a mobile phase of petroleum ether and ethyl acetate (25:75) to obtain hydroxylated all-trans retinoic acid ATRA-OH.

[0013] (2) 100 mg of ATRA-OH and 76 mg of CDI obtained in step (1) were dissolved in 4 ml of dichloromethane. The reaction system was stirred at room temperature for about 2 hours under the protection of nitrogen. The reaction solution was diluted with dichloromethane and washed twice with water and once with saturated brine. The reaction solution after extraction was dried with anhydrous sodium sulfate and then rotary evaporated to remove the organic solvent to obtain the product CDI-activated all-trans retinoic acid ATRA-CDI.

[0014] (3) Dissolve 200 mg of DPA and 151 mg of SA in 5 ml of tetrahydrofuran. The reaction is heated under reflux at 80°C overnight. After the reaction solution returns to room temperature, the organic solvent is removed by rotary evaporation to obtain a crude product of DPA-COOH. The crude product is directly used in the next reaction without purification. Dissolve 12.25 mg of crude DPA-COOH, 12.3 mg of sulfo-NHS and 10.86 mg of EDC in PBS (pH = 6). The reaction is carried out at room temperature for 15 minutes to obtain DPA-NHS-sulfo, which is directly used in the next reaction.

[0015] (4) 18 mg of MAL-PEG-NHS and 4.4 mg of DAG polypeptide were dissolved in HEPES (10 mM, pH = 7). The reaction was stirred at room temperature for 2 hours under nitrogen protection, and the mixture was directly used for the next reaction after the reaction was completed.

[0016] (5) 25 mg PAH, 14.6 mg ATRA-CDI, 4 mg DMAP and 3.37 mg TEA were dissolved in methanol. The reaction was stirred at room temperature overnight and dialyzed with pure water for 24 h. HEPES was added to the reaction aqueous solution to prepare a HEPES reaction system (500 mM, pH = 7.4) and the DPA-NHS-sulfo solution in step (3) was added and stirred at room temperature for 2 hours. Then, DAG-PEH-NHS in step (4) was added to the reaction system and continued to stir at room temperature for 2 hours. The final reaction solution was dialyzed with pure water for 24 hours and lyophilized to obtain the final product D-PPA.

[0017] Synthesis of HCQ-loaded A-PPH polymer:

[0018] (1) Dissolve 200 mg HCQ and 65.55 mg SA in 5 ml tetrahydrofuran. The reaction is heated under reflux at 80°C overnight. After the reaction solution returns to room temperature, the organic solvent is removed by rotary evaporation to obtain a crude product of HCQ-COOH. The crude product is used directly in the next reaction without purification. Dissolve 29 mg of the crude HCQ-COOH, 15.21 mg of sulfo-NHS and 13.42 mg of EDC in PBS (pH = 6). The reaction is carried out at room temperature for 15 minutes to obtain HCQ-NHS-sulfo, which is directly used in the next reaction.

[0019] (2) 18 mg of MAL-PEG-NHS and 5.28 mg of Ab polypeptide were dissolved in HEPES (10 mM, pH = 7). The reaction was stirred at room temperature for 2 hours under nitrogen protection, and the next step was directly carried out after the reaction was completed.

[0020] (3) 25 mg PAH was dissolved in HEPES (500 mM, pH = 7.4), and the HCQ-NHS-sulfo solution in step (1) was added to the reaction solution and stirred at room temperature for 2 hours. Then the Ab-PEG-NHS solution in step (2) and 2.72 mg AC were added to the reaction solution and stirred for another 2 hours. The final reaction solution was dialyzed with pure water for 24 hours and freeze-dried to obtain the final product A-PPH.

[0021] The present invention provides a method for forming a polydopamine nanocore by oxidative polymerization of dopamine, comprising the following steps:

[0022] (1) Mix 9 ml ultrapure water, 4 ml ethanol and 0.8 ml ammonia water and stir at room temperature for 30 minutes. Weigh 50 mg dopamine hydrochloride, dissolve it in 1 ml ultrapure water, add it to the above mixture and continue stirring at room temperature for 24 hours. Polydopamine is purified by ultrafiltration until the lower filtrate is nearly colorless. The upper solution is taken out and filtered with a 0.22 μm filter membrane to obtain a polydopamine nanocore solution.

[0023] The present invention provides a method for synthesizing a ROS-sensitive cross-linking agent, comprising the following steps:

[0024] (1) 4.1 ml of mercaptopropionic acid and 7 ml of anhydrous acetone were added to a reaction flask, 500 g of sodium chloride was dried to remove moisture, and about 200 ml of concentrated sulfuric acid was dripped into the sodium chloride using a constant pressure dropping funnel to generate hydrogen chloride gas. The generated gas was passed into the reaction flask after removing moisture with concentrated sulfuric acid, stirred at room temperature for 6 hours, and the gas was dissolved in sodium hydroxide solution using an exhaust gas treatment device for neutralization. After the reaction was completed, the reaction solution was placed at -20 ° C to cool and crystallize overnight. The next day, the reaction solution was filtered, and the crystallized product was rinsed once and 3 times with cold n-hexane and water respectively, and vacuum dried to obtain the carboxylated ROS sensitive bond TK-COOH.

[0025] (2) Take 200 mg of TK-COOH from step (1), 319 mg of EDC, 203 mg of DMAP and 228 mg of NHS and dissolve them in dichloromethane. The reaction is stirred overnight at room temperature. Add an appropriate amount of 400 mesh silica gel powder to the reaction solution and evaporate it to dryness by rotary evaporation. The spin-dried silica gel is loaded into a column and separated by a mobile phase of petroleum ether and ethyl acetate (5:95) to obtain NHS-modified ROS-sensitive bond TK-NHS.

[0026] The present invention provides a DA-PPHA TK @PDA nanoplatform synthesis method:

[0027] (1) A certain amount of drug-loaded polymer materials (D-PPA and A-PPH) and polydopamine nanocores were mixed in a mass ratio of 2:3. After the solution was subjected to water bath ultrasound for 10 minutes, TK-linker equivalent to 25 times the molar number of the drug-loaded polymer was added and continued to be stirred at room temperature for 1 hour. The resulting cross-linked nanoplatform was ultrafiltered to remove free polymers and cross-linkers to obtain the final DA-PPHA TK @PDA nano platform.

[0028] The present invention provides a nano-platform for multi-cell targeting and multi-drug delivery for inflammation-related diseases and a preparation method thereof. The advantages and effects of the nano-platform are as follows:

[0029] 1. The preparation steps of nanoformulations are simple, the stability is high, and the high drug loading is conducive to clinical transformation and mass production;

[0030] 2. The nanomedicine can deliver different drugs in proportion to multiple cells in a specific manner in the same system;

[0031] 3. This nanomedicine can target inflammatory sites, reduce systemic toxicity in non-target sites, and has good biocompatibility and safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a roadmap for the synthesis of drug-loaded polymers and TK-linker.

[0033] Figure 2 This is the H-NMR spectrum of the drug-loaded polymer and TK-linker.

[0034] Figure 3 It is a statistical histogram of particle size and surface potential of the nano-platform, wherein A is a statistical histogram of particle size and TEM image of the nano-platform, and B is a statistical histogram of surface potential of the nano-platform.

[0035] Figure 4 In vitro drug release diagram of the nanoplatform.

[0036] Figure 5 This is a statistical diagram of the fluorescence distribution of major organs and brain distribution data 24 hours after the nanoplatform was injected into the tail vein of APP / PS1 model mice.

[0037] Figure 6 This is the therapeutic effect of the nanoplatform after tail vein injection of APP / PS1 model mice, where A is the water maze trajectory diagram and B is the nesting experiment result diagram. DETAILED DESCRIPTION

[0038] The present invention is described in detail below with reference to the embodiments.

[0039] Example 1: Drug-loaded polymer on the surface of nanoplatform, the polymer synthesis method is as follows Figure 1 As shown, the following steps are included:

[0040] Synthesis of ATRA-loaded D-PPA polymer:

[0041] (1) Dissolve 200 mg ATRA, 34.39 mg ethylene glycol, 67.77 mg DMAP and 106.3 mg EDC in 5 ml dichloromethane. The reaction system is stirred at room temperature for about 10 hours under the protection of nitrogen. Add an appropriate amount of 400 mesh silica gel powder to the reaction solution and evaporate it to dryness. The spin-dried silica gel is loaded into a column and separated by a mobile phase of petroleum ether and ethyl acetate (25:75) to obtain hydroxylated all-trans retinoic acid ATRA-OH.

[0042] (2) 100 mg of ATRA-OH and 76 mg of CDI obtained in step (1) were dissolved in 4 ml of dichloromethane. The reaction system was stirred at room temperature for about 2 hours under the protection of nitrogen. The reaction solution was diluted with dichloromethane and washed twice with water and once with saturated brine. The reaction solution after extraction was dried with anhydrous sodium sulfate and then rotary evaporated to remove the organic solvent to obtain the product CDI-activated all-trans retinoic acid ATRA-CDI.

[0043] (3) Dissolve 200 mg of DPA and 151 mg of SA in 5 ml of tetrahydrofuran. The reaction is heated under reflux at 80°C overnight. After the reaction solution returns to room temperature, the organic solvent is removed by rotary evaporation to obtain a crude product of DPA-COOH. The crude product is directly used in the next reaction without purification. Dissolve 12.25 mg of crude DPA-COOH, 12.3 mg of sulfo-NHS and 10.86 mg of EDC in PBS (pH = 6). The reaction is carried out at room temperature for 15 minutes to obtain DPA-NHS-sulfo, which is directly used in the next reaction.

[0044] (4) 18 mg of MAL-PEG-NHS and 4.4 mg of DAG polypeptide were dissolved in HEPES (10 mM, pH = 7). The reaction was stirred at room temperature for 2 hours under nitrogen protection, and the mixture was directly used for the next reaction after the reaction was completed.

[0045] (5) 25 mg PAH, 14.6 mg ATRA-CDI, 4 mg DMAP and 3.37 mg TEA were dissolved in methanol. The reaction was stirred at room temperature overnight and dialyzed with pure water for 24 h. HEPES was added to the reaction aqueous solution to prepare a HEPES reaction system (500 mM, pH = 7.4) and the DPA-NHS-sulfo solution in step (3) was added and stirred at room temperature for 2 hours. Then, DAG-PEH-NHS in step (4) was added to the reaction system and continued to stir at room temperature for 2 hours. The final reaction solution was dialyzed with pure water for 24 hours and lyophilized to obtain the final product D-PPA.

[0046] Synthesis of HCQ-loaded A-PPH polymer:

[0047] (1) Dissolve 200 mg HCQ and 65.55 mg SA in 5 ml tetrahydrofuran. The reaction is heated under reflux at 80°C overnight. After the reaction solution returns to room temperature, the organic solvent is removed by rotary evaporation to obtain a crude product of HCQ-COOH. The crude product is used directly in the next reaction without purification. Dissolve 29 mg of the crude HCQ-COOH, 15.21 mg of sulfo-NHS and 13.42 mg of EDC in PBS (pH = 6). The reaction is carried out at room temperature for 15 minutes to obtain HCQ-NHS-sulfo, which is directly used in the next reaction.

[0048] (2) 18 mg of MAL-PEG-NHS and 5.28 mg of Ab polypeptide were dissolved in HEPES (10 mM, pH = 7). The reaction was stirred at room temperature for 2 hours under nitrogen protection, and the next step was directly carried out after the reaction was completed.

[0049] (3) 25 mg PAH was dissolved in HEPES (500 mM, pH = 7.4), and the HCQ-NHS-sulfo solution in step (1) was added to the reaction solution and stirred at room temperature for 2 hours. Then the Ab-PEG-NHS solution in step (2) and 2.72 mg AC were added to the reaction solution and stirred for another 2 hours. The final reaction solution was dialyzed with pure water for 24 hours and freeze-dried to obtain the final product A-PPH.

[0050] Example 2: Screening of prescriptions for preparing nanoplatforms, the results are as follows Figure 2 As shown, the following steps are included:

[0051] Synthetic DA-PPHA TK @PDA Nano Platform:

[0052] (1) A certain amount of drug-loaded polymer materials (D-PPA and A-PPH) and polydopamine nanocores were mixed in a mass ratio of 2:3. After the solution was subjected to water bath ultrasound for 10 minutes, TK-linker equivalent to 25 times the molar number of the drug-loaded polymer was added and continued to be stirred at room temperature for 1 hour. The resulting cross-linked nanoplatform was ultrafiltered to remove free polymers and cross-linkers to obtain the final DA-PPHA TK @PDA nano platform.

[0053] Example 3: A method for preparing a nanoplatform labeled with a near-infrared fluorescent probe, comprising the following steps:

[0054] (1) After the final nanoplatform was prepared according to the above steps, 1 mg of water-soluble near-infrared probe Cy5-NHS solution was added to the solution, and stirred at room temperature for 2 hours in a PBS 8.5 buffer medium. After dialysis in the injection medium for 24 hours, the fluorescently labeled nanoplatform was obtained.

[0055] (2) APP / PS1 model mice were injected with nanodrugs containing 1 mg / kg of probe through the tail vein. In vivo imaging was performed at 1, 2, 4, 6, 8, 12, and 24 h to observe the brain targeting of the nanodrugs. The time point with the highest fluorescence intensity was selected for imaging of the ex vivo organs, and the in vivo distribution behavior of the nanodrugs was statistically analyzed, such as Figure 5 shown.

Claims

1. A nanoplatform for multi-cell targeting and multi-drug delivery of inflammatory-related diseases, characterized in that: The invention comprises a therapeutic drug, a synthetic polymer skeleton, a synthetic polydopamine nanocore, a ROS-sensitive cross-linking agent and other pharmaceutically acceptable excipients.

2. The nanoplatform according to claim 1, characterized in that: The nano core surface polymer layer comprises polyallylamine with a molecular weight of 15,000, all-trans retinoic acid ATRA, hydroxychloroquine HCQ, bifunctional PEG, targeting polypeptide and ROS sensitive cross-linking agent.

3. The nanoplatform according to claim 1, characterized in that: The PEG raw material used is a bifunctional group-substituted straight chain (N-hydroxysuccinimide and maleimide modified) with a molecular weight of 5000.

4. The nanoplatform according to claim 1, characterized in that: The nano-platform adopts the dopamine oxidation method to prepare the nano-core, and the particle size of the nano-core is about 60nm.

5. The nanoplatform according to claim 1, characterized in that: The mass ratio of the drug-loaded polymer material to dopamine is 2:3, and the molar ratio of the drug-loaded polymer material to the ROS-sensitive cross-linking agent is 1:

25.

6. The nanoplatform according to claim 1, characterized in that: After self-assembly to form an uncross-linked nanoplatform, the particle size increased by about 20 nm to about 80 nm. After adding a ROS-sensitive cross-linking agent, the particle size decreased by 10 nm to about 70 nm.

7. The nanoplatform according to claim 1, characterized in that: The other pharmaceutically acceptable excipient is an osmotic pressure regulator.

8. The nanoplatform according to claim 1, characterized in that: The formulation solution of the therapeutic agent is isotonic with plasma.

9. The nanoplatform according to claim 2, characterized in that: The targeting polypeptide can bind to the RAGE receptor highly expressed in AD cerebral blood vessels and microglial cells, and the Ab polypeptide sequence is KLVFFAED; and the CTGF receptor highly expressed in cerebral blood vessels and astrocytes, and the DAG polypeptide sequence is a cyclic peptide (CDGRKQKC).

10. The method for preparing a nano-platform according to claim 1, characterized in that: It includes the following steps: 1) Synthesis of ATRA-loaded D-PPA polymer: 2) Synthesis of HCQ-loaded A-PPH polymer: 3) Synthesis of ROS-sensitive cross-linker TK-linker: 4) Synthesis of DA-PPHA TK @PDA nano platform.

11. The preparation method according to claim 10, characterized in that: in, Steps for synthesizing ATRA-loaded D-PPA polymer: (1) 200 mg ATRA, 34.39 mg ethylene glycol, 67.77 mg DMAP and 106.3 mg EDC were dissolved in 5 ml dichloromethane. The reaction system was stirred at room temperature for about 10 hours under the protection of nitrogen. An appropriate amount of 400 mesh silica gel powder was added to the reaction solution and the mixture was dried by rotary evaporation. The dried silica gel was loaded into a column and separated by column separation with a mobile phase of petroleum ether and ethyl acetate (25:75) to obtain hydroxylated all-trans retinoic acid ATRA-OH. (2) 100 mg of ATRA-OH and 76 mg of CDI obtained in step (1) were dissolved in 4 ml of dichloromethane. The reaction system was stirred at room temperature for about 2 hours under the protection of nitrogen. The reaction solution was diluted with dichloromethane and washed twice with water and once with saturated brine. The reaction solution after extraction was dried over anhydrous sodium sulfate and then rotary evaporated to remove the organic solvent to obtain the product CDI-activated all-trans retinoic acid ATRA-CDI; (3) 200 mg of DPA and 151 mg of SA were dissolved in 5 ml of tetrahydrofuran, and the reaction was heated under reflux at 80° C. overnight. After the reaction solution returned to room temperature, the organic solvent was removed by rotary evaporation to obtain a crude product of DPA-COOH, which was directly used in the next reaction without purification. 12.25 mg of the crude product of DPA-COOH, 12.3 mg of sulfo-NHS and 10.86 mg of EDC were dissolved in PBS (pH=6), and the reaction was carried out at room temperature for 15 minutes to obtain DPA-NHS-sulfo, which was directly used in the next reaction; (4) 18 mg of MAL-PEG-NHS and 4.4 mg of DAG polypeptide were dissolved in HEPES (10 mM, pH = 7). The reaction was stirred at room temperature for 2 hours under nitrogen protection. After the reaction was completed, it was directly used for the next reaction; (5) 25 mg PAH, 14.6 mg ATRA-CDI, 4 mg DMAP and 3.37 mg TEA were dissolved in methanol. The reaction was stirred at room temperature overnight and dialyzed with pure water for 24 h. HEPES was added to the reaction aqueous solution to prepare a HEPES reaction system (500 mM, pH = 7.4) and the DPA-NHS-sulfo solution in step (3) was added and stirred at room temperature for 2 hours. Then, DAG-PEH-NHS in step (4) was added to the reaction system and continued to stir at room temperature for 2 hours. Finally, the reaction solution was dialyzed with pure water for 24 hours and lyophilized to obtain the final product D-PPA.

12. The preparation method according to claim 10, characterized in that: in, In the synthesis of HCQ-loaded A-PPH polymer: (1) 200 mg HCQ and 65.55 mg SA were dissolved in 5 ml tetrahydrofuran, and the reaction was heated under reflux at 80° C. overnight. After the reaction solution returned to room temperature, the organic solvent was removed by rotary evaporation to obtain a crude product of HCQ-COOH, which was directly used in the next reaction without purification. 29 mg HCQ-COOH crude product, 15.21 mg sulfo-NHS and 13.42 mg EDC were dissolved in PBS (pH=6), and the reaction was carried out at room temperature for 15 minutes to obtain HCQ-NHS-sulfo, which was directly used in the next reaction; (2) 18 mg of MAL-PEG-NHS and 5.28 mg of Ab polypeptide were dissolved in HEPES (10 mM, pH = 7). The reaction was stirred at room temperature for 2 hours under nitrogen protection. After the reaction was completed, it was directly used for the next reaction; (3) 25 mg PAH was dissolved in HEPES (500 mM, pH = 7.4), and the HCQ-NHS-sulfo solution in step (1) was added to the reaction solution and stirred at room temperature for 2 hours. Then, the Ab-PEG-NHS solution in step (2) and 2.72 mg AC were added to the reaction solution and stirred for another 2 hours. Finally, the reaction solution was dialyzed with pure water for 24 hours and lyophilized to obtain the final product A-PPH.

13. The preparation method according to claim 10, characterized in that: in, Synthesis of ROS-sensitive cross-linker TK-linker: (1) 4.1 ml of mercaptopropionic acid and 7 ml of anhydrous acetone were added to a reaction flask, 500 g of sodium chloride was dried to remove moisture, about 200 ml of concentrated sulfuric acid was added to the sodium chloride using a constant pressure dropping funnel to generate hydrogen chloride gas, the generated gas was removed by concentrated sulfuric acid and then introduced into the reaction flask, stirred at room temperature for 6 hours, and the gas was dissolved in a sodium hydroxide solution using an exhaust gas treatment device for neutralization. After the reaction was completed, the reaction solution was placed at -20°C for cooling and crystallization overnight. The reaction solution was filtered the next day, and the crystallized product was rinsed once and three times with cold n-hexane and water, respectively, and vacuum dried to obtain a carboxylated ROS sensitive bond TK-COOH; (2) 200 mg of TK-COOH prepared in step (1), 319 mg of EDC, 203 mg of DMAP and 228 mg of NHS were dissolved in dichloromethane. The reaction was stirred overnight at room temperature. An appropriate amount of 400-mesh silica gel powder was added to the reaction solution and the mixture was dried by rotary evaporation. The dried silica gel was loaded onto a column and separated by column separation using a mobile phase of a mixture of petroleum ether and ethyl acetate (5:95) to obtain NHS-modified ROS-sensitive bond TK-NHS.

14. The preparation method according to claim 10, characterized in that: in, Synthetic DA-PPHA TK @PDA nano platform: The drug-loaded polymer materials D-PPA and A-PPH were mixed with polydopamine nanocores in a mass ratio of 2:

3. The solution was subjected to water bath ultrasound for 10 minutes, and then TK-linker equivalent to 25 times the molar number of the drug-loaded polymer was added and continued to be stirred at room temperature for 1 hour. The resulting cross-linked nanoplatform was ultrafiltered to remove free polymers and cross-linkers to obtain DA-PPHA. TK @PDA nano platform.

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