Module-engineered self-adaptive nano platform as well as preparation method and application thereof

Abstract

The invention discloses a module-engineered self-adaptive nano-platform as well as a preparation method and application thereof, and belongs to the technical field of nano-drugs. According to the nano-platform disclosed by the invention, PTi nano-particles with brain tumor targeting ability and a PEG-Bis-Cys-CHO polymer are mixed, an aldehyde group and a thiol group are introduced to two ends of a PEG chain, BBB penetrating peptide (Te) with maleimide at the tail end is designed, and through an efficient click chemical reaction (thiol-maleimide reaction), the brain tumor targeting ability of the PTi nano-particles is improved, and the brain tumor targeting ability of the PTi nano-particles is improved. The full-chain optimization strategy from molecular design to nanometer engineering ensures that therapeutic drugs can be accurately gathered in brain tumor cells, meanwhile, damage to normal cells is reduced to the maximum extent, continuous and efficient targeting from the blood brain barrier to the tumor cells can be achieved, and accurate, safe and efficient treatment of brain tumors is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of nanomedicine, and in particular relates to a modular engineered adaptive nanoplatform and a preparation method and application thereof. Background Art

[0002] In clinical practice, although the treatment plan for glioblastoma multiforme (GBM) is centered on maximum surgical resection, supplemented by temozolomide chemotherapy and radiotherapy as standard treatment, the improvement in treatment effect has been quite limited over the years. The median survival of patients is generally limited to 15 months, and the overall 5-year survival rate is less than 6%, highlighting the severity of the treatment challenge. The invasive and infiltrative growth of GBM makes it very easy to damage healthy brain tissue during surgery, increasing the risk and complexity of craniotomy. Especially when GBM lesions are located deep in the brain, the difficulty of surgical intervention is significantly increased, which brings huge challenges to the formulation and implementation of effective treatment plans.

[0003] In view of the above dilemma, a minimally invasive alternative method has been explored. This technology can achieve precise ablation of brain tumors under the precise navigation of real-time magnetic resonance imaging. Magnetic resonance-guided focused ultrasound is another alternative method that uses magnetic resonance imaging to control ultrasound. The high heat generated by ultrasound can be used for non-invasive tumor ablation. However, these technologies not only rely on high-end equipment, but also highly test the surgeon's operating skills and teamwork, and the high thermal effect may still involve adjacent healthy tissues, bringing potential risks. In contrast, photodynamic therapy, with its short-lived reactive oxygen species produced by its photosensitizer and limited propagation distance, shows unique advantages in reducing damage to normal tissues, but its efficacy is still limited by the tumor targeting and bioavailability issues of existing photosensitizers.

[0004] Chemotherapy, as a traditional mainstay of tumor treatment, also plays an important role in the treatment of glioblastoma, but its efficacy is often greatly reduced due to the obstruction of the blood-brain barrier, tumor heterogeneity and high invasiveness. Although temozolomide, as a first-line chemotherapy drug, can cross the blood-brain barrier and assist in postoperative treatment, it also faces challenges such as poor drug targeting and significant side effects, especially toxic effects on the blood system, which increases the risk of infection and coagulation disorders in patients. Therefore, how to accurately target tumors while minimizing the side effects of treatment has become a key issue that needs to be urgently addressed in the current field of glioblastoma treatment.

[0005] Nanomedicines, with their excellent controllability, versatility and tumor targeting capabilities, provide new ideas for breaking through the above-mentioned treatment bottlenecks. Carefully designed nanomedicines can not only improve the bioavailability of drugs, but also achieve precise targeting or enhance cell permeability through the modification of surface ligands. However, the design of nanomedicines needs to take into account multiple conflicting needs, such as maintaining a balance between blood stability and promoting rapid intracellular release, optimizing particle size to penetrate tissues without being cleared by the kidneys, and controlling surface charge to promote cell absorption while avoiding protein adsorption. When exploring intracranial drug delivery routes, although ultrasound technology can temporarily open the blood-brain barrier, its potential risk of pathogen invasion cannot be ignored. In contrast, the active targeting strategy using functional ligands is safer and aims to directly enhance the ability of nanomedicines to cross the blood-brain barrier and precisely target glioblastoma. However, how to achieve continuous and efficient targeting from the blood-brain barrier to tumor cells is still a major challenge facing current nanomedicine research.

[0006] In the process of drug delivery to glioblastoma (GBM), multiple biological barriers need to be overcome, including circulatory barriers (such as blood shear force, immune system conditioning, and drug renal clearance), tissue barriers (such as blood-brain barrier, low permeability caused by the dense structure and heterogeneity inside tumor tissue), and cell barriers (such as transmembrane endocytosis efficiency of cell membrane, effective release of drugs in cells, etc.). Summary of the invention

[0007] The purpose of the present invention is to provide a modular engineered adaptive nanoplatform and its preparation method and application, so as to solve the technical problem of continuous and efficient targeting from the blood-brain barrier to tumor cells that is difficult to achieve with existing nanomedicines, as well as clinical problems such as high invasiveness, poor therapeutic effect, strong toxic side effects, and no significant progress in treatment plans for malignant brain tumors.

[0008] In order to achieve the above object, the present invention adopts the following technical solutions: The present invention discloses a method for preparing a modular engineered adaptive nano-platform, comprising the following steps: PTi nanoparticles and PEG- Bis -Cys-CHO polymers are mixed, Te is added after stirring, and after continuous stirring, ultrafiltration centrifugation purification is performed to obtain a modular engineered adaptive nano-platform.

[0009] Furthermore, the PTi nanoparticles, PEG- Bis The usage ratio of -Cys-CHO polymer and Te is (350~445)μL: (5~100)μL: (5~100)μL.

[0010] Furthermore, the stirring is carried out under a nitrogen protection environment; the stirring time is 12 to 24 hours; The continuous stirring time is 10 to 12 hours; The molecular weight cut-off of the ultrafiltration centrifugation purification process is 7000 Da.

[0011] Furthermore, the PEG- Bis -Cys-CHO polymer is prepared by: PEG- Bis -Cys(Trt)-CHO polymer was dissolved in dichloromethane, and nitrogen was continuously introduced under ice bath conditions to form a mixed system; Trifluoroacetic acid and triisopropylsilane were added to the mixed system in sequence, and the mixture was stirred and then post-treated to obtain PEG- Bis -Cys-CHO polymer.

[0012] Furthermore, the PEG- Bis The usage ratio of -Cys(Trt)-CHO polymer, dichloromethane, trifluoroacetic acid, and triisopropylsilane is 300 mg: 6~10 mL: 670~1117 μL: 300~500 μL.

[0013] Furthermore, the PEG- Bis The preparation method of the -Cys(Trt)-CHO polymer comprises: S1: O,O′-bis(2-aminoethyl)polyethylene glycol, Fmoc-Cys(Trt)-OH and dichloromethane are mixed to obtain a reaction mixture; anhydrous dichloromethane containing dicyclohexylcarbodiimide is added dropwise to the reaction mixture under ice bath conditions to react, and PEG- Bis -Fmoc-Cys(Trt) polymer; S2: PEG- Bis -Fmoc-Cys(Trt) polymer was dissolved in the mixed solvent and stirred to obtain PEG- Bis -Cys(Trt) polymer; S3: 4-Carboxybenzaldehyde, 1H-benzotriazol-1-yloxytripyrrolidino hexafluorophosphate and N,N-diisopropylethylamine were dissolved in dichloromethane, followed by the addition of PEG- Bis -Cys(Trt) polymer, and then stirred to obtain PEG- Bis -Cys(Trt)-CHO polymer.

[0014] Furthermore, in S1, the amount ratio of the O,O′-bis(2-aminoethyl)polyethylene glycol, Fmoc-Cys(Trt)-OH, dichloromethane and anhydrous dichloromethane containing dicyclohexylcarbodiimide is 0.5-1 g: 484-968 mg: 15-30 mL: 15-20 mL; the content of dicyclohexylcarbodiimide in the anhydrous dichloromethane containing dicyclohexylcarbodiimide is 173 mg / 2 mL; In S2, PEG- Bis -Fmoc-Cys (Trt) polymer and mixed solvent are used in a ratio of 500-1000 mg: 1-2 mL; the mixed solvent is composed of 4-methylpiperidine and dimethylformamide; the volume ratio of 4-methylpiperidine and dimethylformamide is 1:4; In S3, 4-carboxybenzaldehyde, 1H-benzotriazol-1-yloxytripyrrolidino hexafluorophosphate, N,N-diisopropylethylamine, dichloromethane and PEG- Bis -Cys (Trt) polymer dosage ratio is 40~70mg: 138~276mg: 44~88μL: 8~20mL: 5~10mL; the PEG- Bis -Cys(Trt) polymers in PEG- Bis The content of -Cys(Trt) polymer was 323 mg / 5 mL.

[0015] Furthermore, the preparation method of the PTi nanoparticles is: The PTi monomer is dissolved in methanol and stirred to obtain a PTi monomer solution; the PTi monomer solution is dropped into deionized water under stirring, and the obtained mixed solution is subjected to ultrafiltration and centrifugation to obtain PTi nanoparticles; The usage ratio of the PTi monomer, methanol and deionized water is 5 mg:400 μL:1.5 mL.

[0016] The invention also discloses a modular engineered adaptive nano platform prepared by the preparation method.

[0017] The present invention also discloses the application of the modular engineered adaptive nano-platform in fighting brain tumors.

[0018] Compared with the prior art, the present invention has the following beneficial effects: The present invention discloses a method for preparing a modular engineered adaptive nano-platform, which comprises PTi nanoparticles with GBM targeting capability and PEG- Bis-Cys-CHO polymers are mixed, and aldehyde groups and thiol groups are introduced at both ends of the PEG chain. The aldehyde groups react with the lysine amino groups on the surface of the PTi nanoparticles to form pH-sensitive Schiff base bonds, which not only effectively shield the positive charge, but also enhance the stability of the nanoparticles. At the same time, the exposed thiol groups provide the possibility for subsequent functional modification. In order to give PTi nanoparticles the ability to cross the blood-brain barrier, the present invention designs a BBB-penetrating peptide (Te) with maleimide at the end. Through efficient click chemistry (thiol-maleimide reaction), Te molecules are accurately introduced into the surface of PEG-crosslinked PTi nanoparticles to form a PTi-c-Te structure. Due to surface PEG crosslinking, its circulation time in the body is significantly prolonged. In the process of receptor-mediated transcytosis, as the environmental pH changes, the Schiff base bond is cleaved, and the PEG crosslinking layer gradually falls off, exposing the positively charged PTi nanomicelle surface and its GBM targeting peptide, thereby achieving a precise transition from crossing the BBB to GBM targeting. This process not only overcomes the biological barrier, but also significantly improves the accuracy and efficiency of drug delivery. The cleaved PTi micelles, with their tiny size and enhanced positive charge, can penetrate deep into the tumor tissue and be efficiently taken up by cells. This full-chain optimization strategy from molecular design to nanoengineering ensures that therapeutic drugs can be precisely concentrated in GBM cells while minimizing damage to normal cells. The modular engineered adaptive nanoplatform can achieve continuous and efficient targeting from the blood-brain barrier to tumor cells.

[0019] Furthermore, by coupling the hydrophilic GBM-targeting peptide RGD (containing one lysine) with the photosensitizer PpIX carrying a short flexible linker, we synthesized the photosensitizer-ligand amphiphilic compound PTi. These PTi monomers can spontaneously aggregate into stable PTi micelles, and then quickly form PTi nanoparticles with GBM targeting ability through the tight aggregation of multiple micelles.

[0020] Furthermore, relevant experimental results have proved that the modular engineered adaptive nanoplatform has efficient targeting and drug controlled release capabilities, achieving precise drug delivery and effective release, directly acting on GBM lesions, and providing GBM patients with a more convenient, efficient and safe treatment option. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The results of SGIPi-based interstitial photodynamic therapy of the present invention; Among them: a-timeline of intracranial GBM inoculation and subsequent treatment and MRI monitoring; b-MRI imaging of intracranial tumors in mice; c-changes in intracranial tumor volume; d-survival curve of mice after treatment; e-whole brain H&E staining of mice treated with normal saline; f-whole brain H&E staining of mice treated with PTi-c-Te; j-tumor and body weight changes of individual mice; Figure 2 The results of SGIPi-based chemotherapy treatment of the present invention; Among them: a-experimental timetable; b-MRI imaging of intracranial tumors in mice; c-changes in intracranial tumor volume in mice in the normal saline group; d-changes in intracranial tumor volume in mice after free TMZ treatment; e-changes in intracranial tumor volume in mice after treatment with the TMZ-loaded adaptive nanoplatform; f-changes in intracranial tumor volume in mice after different treatments; g-survival curves of mice after different treatments; h-weight changes in mice after different treatments; i-white blood cell counts in whole blood of mice after different treatments; j-platelet counts in whole blood of mice after different treatments; k-red blood cell counts in whole blood of mice after different treatments; Figure 3 Schematic diagram of modular construction of different nanoplatforms. DETAILED DESCRIPTION

[0022] In order to enable those skilled in the art to understand the characteristics and effects of the present invention, the following is a general description and definition of the terms and expressions mentioned in the specification and claims. Unless otherwise specified, all technical and scientific terms used in the text are the common meanings understood by those skilled in the art for the present invention. In the event of a conflict, the definition in this specification shall prevail.

[0023] The theories or mechanisms described and disclosed herein, whether correct or incorrect, should not limit the scope of the present invention in any way, that is, the present invention can be implemented without being limited by any specific theory or mechanism.

[0024] In this article, all features such as values, quantities, contents and concentrations defined in the form of numerical ranges or percentage ranges are for simplicity and convenience only. Accordingly, the description of numerical ranges or percentage ranges should be considered to have included and specifically disclosed all possible secondary ranges and individual values ​​within the range (including integers and fractions).

[0025] In this document, unless otherwise specified, “includes,” “including,” “contains,” “has,” or similar terms cover the meanings of “consisting of” and “mainly consisting of,” for example, “A includes a” covers the meanings of “A includes a and other” and “A only includes a.”

[0026] In this document, in order to make the description concise, not all possible combinations of various technical features in various embodiments or examples are described. Therefore, as long as there is no contradiction in the combination of these technical features, the various technical features in various embodiments or examples can be combined arbitrarily, and all possible combinations should be considered to be within the scope of this specification.

[0027] The present invention discloses a modularly engineered adaptive nano-platform, which is an intravenous drug carrier that can adapt to the physiological environment at different stages and thus change the ligand and physicochemical properties, and is used to improve pharmacokinetics, avoid liver and kidney clearance, and achieve blood-brain barrier penetration and intracranial lesion targeting. By dynamically adjusting the ligand, particle size, potential and other properties, it can achieve adaptive crossing of the physiological barrier and differentiated lesion responses to external stimuli.

[0028] The modular engineered adaptive nano-platform disclosed in the present invention is represented as PTi-c-Te nano-platform (SAN), wherein P represents hydrophobic photosensitizers such as protoporphyrin IX (PpIX), chlorin e6 (Ce6), and pyropheophorbide a (Ppa); Ti represents relevant water-soluble ligands of various integrin receptors, transferrin receptors, insulin receptors, low-density lipoprotein receptors, glucose transporters, amino acid transporters, etc. targeting the blood-brain barrier, including small molecules, peptides, and proteins; -c- represents a polyethylene glycol-based material that is designed to respond to an acidic environment and then form chemical bonds such as Schiff bases and phenylboronic acid esters to achieve specific biological or chemical functions; Te represents ligands that can target intracranial lesions, including small molecules, peptides, and proteins. The molecules or ligands involved in each module can be freely combined in the order of P, Ti, -c-, and Te to meet the delivery requirements of different tumor types.

[0029] The modular engineered adaptive nanoplatform disclosed in the present invention can dynamically adjust its structure, surface charge, particle size and ligand characteristics according to changes in the physiological environment, so as to accurately navigate to overcome the above-mentioned barriers and achieve precise targeting of GBM cells while minimizing nonspecific effects on adjacent normal brain tissues.

[0030] Based on the excellent targeting capability of the SAN platform, the present invention further proposes a SAN-guided intuitive and precise intervention (SGIPi) strategy to treat GBM. This strategy not only simplifies the treatment process without relying on complex medical equipment, but also avoids the superb operating skills and real-time MRI monitoring required by technologies such as laser interstitial thermal therapy (LITT) and magnetic resonance-guided focused ultrasound (MRgFUS), thereby lowering the treatment threshold and improving the accessibility and safety of treatment.

[0031] The core of the SGIPi strategy is to utilize the efficient targeting and drug controlled release capabilities of the adaptive nanoplatform to achieve precise drug delivery and effective release, directly acting on GBM lesions, and providing GBM patients with a more convenient, efficient and safe treatment option.

[0032] The PEG- Bis The synthesis scheme of -Cys-CHO polymer is shown in the following reaction formula: .

[0033] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall within the scope limited by the appended claims of the application equally.

[0034] The following examples use conventional instruments and equipment in the art. The experimental methods in the following examples where specific conditions are not specified are usually carried out under conventional conditions or under conditions recommended by the manufacturer. The various raw materials used in the following examples are conventional commercial products unless otherwise specified, and their specifications are conventional specifications in the art. In the specification of the present invention and the following examples, unless otherwise specified, "%" means weight percentage, "part" means weight part, and ratio means weight ratio.

[0035] Example 1 A method for preparing a modular engineered adaptive nanoplatform comprises the following steps: S1: PEG- Bis -Fmoc-Cys(Trt) polymer synthesis, O,O′-bis(2-aminoethyl)polyethylene glycol (0.5 g, molecular weight 2000) and Fmoc-Cys(Trt)-OH (484 mg) were fully dissolved in 15 mL of dry dichloromethane. Then, 2 mL of anhydrous dichloromethane containing dicyclohexylcarbodiimide (173 mg) was slowly added to the reaction mixture by syringe under ice bath conditions. The reaction progress was continuously monitored by thin layer chromatography combined with iodine staining technique under 254 nm ultraviolet light irradiation; the post-treatment procedure for purification was as follows: vacuum filtration was used to remove the generated white N,N′-dicycloethylurea byproduct, and the filtrate was concentrated by rotary evaporator and precipitated in ice-cold ether. The crude product was washed with ether several times and monitored by thin layer chromatography to remove impurities. Subsequently, the crude product was dissolved in acetone and purified by dialyzing through a dialysis tube with a molecular cutoff of 1000 Da. Finally, the purified PEG- Bis -Fmoc-Cys(Trt) polymer was freeze-dried and used as the starting material for subsequent chemical reactions; S2: PEG- Bis -Cys(Trt) polymer synthesis, PEG- Bis -Fmoc-Cys(Trt) (500 mg) polymer was dissolved in 1 mL of a mixed solvent consisting of 4-methylpiperidine / dimethylformamide (vol:vol = 1:4) and stirred for 1 h. The post-treatment procedure was the same as that of PEG- Bis -Fmoc-Cys(Trt) polymers are similar; S3: PEG- Bis To synthesize the PEG-Cys(Trt)-CHO polymer, 4-carboxybenzaldehyde (4-CBA, 40 mg, 2.2 eq), 1H-benzotriazol-1-yloxytripyrrolidino hexafluorophosphate (PyBOP, 138 mg, 2.2 eq) and N,N-diisopropylethylamine (DIEA, 44 μL, 2.1 eq) were dissolved in 8 mL of dry dichloromethane. Subsequently, PEG- Bis -Cys(Trt) polymer (323 mg, 1 eq) was added and stirred continuously. The progress of the reaction was visually monitored by thin layer chromatography using 254 nm UV light irradiation and iodine colorimetric technique; after the reaction was completed, the post-treatment procedure was the same as that of PEG- Bis -Fmoc-Cys(Trt) polymers are consistent; S4: PEG- Bis Synthesis of -Cys-CHO polymers, PEG- Bis -Cys(Trt)-CHO polymer (300 mg) was dissolved in 6 mL of dry dichloromethane and nitrogen was continuously introduced under ice bath conditions. Subsequently, trifluoroacetic acid (TFA, 670 μL) and triisopropylsilane (TIPS, 300 μL) were added to the mixed system in sequence, and after stirring for 30 min, the post-treatment procedure was referred to the PEG- Bis -Fmoc-Cys(Trt) polymer; S5: Add 5 μL of PEG- Bis -Cys-CHO polymer (4.3 mM), and then stirred for 24 h under nitrogen protection. After that, 5 μL of Te was added to the above mixture and stirred for 12 h. Then, the PTi-c-Te nanoplatform was purified by ultrafiltration centrifugation (molecular weight cutoff = 7000 Da).

[0036] Example 2 Different from Example 1, in S7, 10 μL of PEG-Bis -Cys-CHO polymer (4.3 mM), and then stirred for 24 h under nitrogen protection. After that, 10 μL of Te was added to the above mixture and stirred for 12 h. Then, the PTi-c-Te nanoplatform was purified by ultrafiltration centrifugation (molecular weight cutoff = 7000 Da).

[0037] Example 3 Different from Example 1, in S7, 25 μL of PEG- Bis -Cys-CHO polymer (4.3 mM), and then stirred for 24 h under nitrogen protection. After that, 25 μL of Te was added to the above mixture and stirred for 12 h. Then, the PTi-c-Te nanoplatform was purified by ultrafiltration centrifugation (molecular weight cutoff = 7000 Da). Example 4 Different from Example 1, in S7, 50 μL of PEG- Bis -Cys-CHO polymer (4.3 mM), and then stirred for 24 h under nitrogen protection. After that, 50 μL of Te was added to the above mixture and stirred for 12 h. Then, the PTi-c-Te nanoplatform was purified by ultrafiltration centrifugation (molecular weight cutoff = 7000 Da).

[0038] Example 5 Different from Example 1, in S7, 100 μL of PEG- Bis -Cys-CHO polymer (4.3 mM), and then stirred for 24 h under nitrogen protection. After that, 100 μL of Te was added to the above mixture and stirred for 12 h. Then, the PTi-c-Te nanoplatform was purified by ultrafiltration centrifugation (molecular weight cutoff = 7000 Da).

[0039] Example 6 Different from Example 5, PEG- Bis The ratio of the amount of -Cys(Trt)-CHO polymer, dichloromethane, trifluoroacetic acid, and triisopropylsilane was 300 mg: 6 mL: 670 μL: 300 μL, the ratio of the amount of O,O′-bis(2-aminoethyl)polyethylene glycol, Fmoc-Cys(Trt)-OH, dichloromethane, and anhydrous dichloromethane containing dicyclohexylcarbodiimide was 1 g: 968 mg: 30 mL: 4 mL, and the ratio of the amount of PEG- BisThe amount ratio of -Fmoc-Cys(Trt) polymer and mixed solvent was 1000 mg:40 mL; 4-carboxybenzaldehyde, 1H-benzotriazol-1-yloxytripyrrolidino hexafluorophosphate, N,N-diisopropylethylamine, dichloromethane and PEG- Bis The dosage ratio of -Cys(Trt) polymer is 70 mg:276 mg:88 μL:10 mL:10 mL; the rest is the same as Example 5.

[0040] Comparative Example 1 A method for preparing a PTi-n-Te nanoplatform using a layer-by-layer engineering strategy comprises the following steps: Different amounts (5 μL, 10 μL, 25 μL, 50 μL, 100 μL) of PEG- Bis -Cys-CHO polymer (4.3 mM), followed by stirring for 24 hours under nitrogen protection. Afterwards, Te (8.6 mM, 5 μL, 10 μL, 25 μL, 50 μL, 100 μL) was added to the above mixture, respectively, and stirring was continued for 12 h. Afterwards, the Schiff base was converted to a secondary amine bond that could not be cleaved by weak acid by adding sodium cyanoborohydride (NaBH3CN, 6 times the equivalent of Schiff base). Then, the PTi-n-Te nanoplatform was purified by ultrafiltration centrifugation (molecular weight cutoff = 7000Da).

[0041] Comparative Example 2 A method for preparing a PTi-c-Se nanoplatform using a layer-by-layer engineering strategy comprises the following steps: Different amounts (5 μL, 10 μL, 25 μL, 50 μL, 100 μL) of PEG- Bis -Cys-CHO polymer (4.3 mM), followed by stirring for 24 h under nitrogen protection. Afterwards, Se (8.6 mM, 5 μL, 10 μL, 25 μL, 50 μL, 100 μL) was added to the above mixture, and stirring continued for 12 h. Then, the PTi-c-Se nanoplatform was purified by ultrafiltration centrifugation (molecular weight cutoff = 7000 Da).

[0042] Comparative Example 3 A layer-by-layer engineering strategy was used to prepare the PSi-c-Te nanoplatform. Different amounts (5 μL, 10 μL, 25 μL, 50 μL, 100 μL) of PEG- Bis -Cys-CHO polymer (4.3 mM), followed by stirring for 24 h under nitrogen protection. Afterwards, Te (8.6 mM, 5 μL, 10 μL, 25 μL, 50 μL, 100 μL) was added to the above mixture, and stirring continued for 12 h. Then, the PTi-c-Te nanoplatform was purified by ultrafiltration centrifugation (molecular weight cutoff = 7000 Da).

[0043] In order to verify the therapeutic effect of the modular engineered adaptive nano-platform disclosed in the present invention in photodynamic therapy, the following experiments were conducted: Twenty-five mice bearing intracranial tumors were constructed, all of which were BALB / c athymic nude mice, about 6 weeks old, female; tumor cells were injected into the bregma, 1 mm lateral, 0.5 mm in front, and 3.6 mm deep; Efficacy criteria: (1) Evaluate the therapeutic effect by intracranial tumor volume; (2) Safety was assessed by the distribution of apoptotic cells in brain tissue sections.

[0044] Treatment: The phototherapy efficacy of the modular engineered adaptive nanoplatform prepared by the present invention and the different nanoplatforms of Comparative Examples 1 to Comparative Examples 3 were evaluated by nude mice carrying intracranial tumors. These nanoplatforms were intravenously injected into nude mice on days 0, 4, and 8, and intracranial laser irradiation (20 J / cm², 10 min) was performed 6 h and 24 h after administration, respectively. The treatment was implemented using a specially designed optical fiber (outer diameter 0.2 mm, length customized according to the distance from the tumor center to the outer surface of the skull determined by MRI); the optical fiber was inserted through a pre-drilled hole to implement photodynamic therapy. Subsequently, the tumor size was monitored on days 4, 8, 14, and 18 using a magnetic resonance imaging system (9.4T, BioSpec 94 / 30, Bruker), and the tumor volume was calculated using a specific formula. At the same time, the weight of the nude mice was continuously monitored until the humane endpoint standard was reached, that is, the weight continued to decrease by 20% compared to the initial value or until natural death.

[0045] Treatment results: Figure 1The results of SGIPi-based interstitial photodynamic therapy. As can be seen from the figure, in the saline-treated group, the intracranial tumor volume increased significantly on the 8th day, and 2 mice died on the 18th day; mice treated with PTi-n-Te, PTi-c-Se and PSi-c-Te showed highly rapid tumor development, indicating that size / charge conversion and continuous cross-BBB and GBM targeting capabilities are crucial for the nanoplatform to effectively treat intracranial tumors; PTi-c-Te showed imperceptible intracranial tumor progression, proving that nanoparticles with triple conversion can effectively inhibit intracranial tumors through photodynamic therapy.

[0046] In addition, the median overall survival of mice in the saline group, PTi-c-Se group, PTi-n-Te group, and PSi-c-Te group were 21 days, 24 days, 29 days, and 30 days, respectively; in contrast, more than 80% of the mice in the PTi-c-Te treatment group survived for more than 42 days (equivalent to 4.72 years in humans), indicating that adaptive nanoplatform-guided photodynamic therapy is highly effective in treating intracranial tumors.

[0047] It is worth noting that large areas of tumor lesions appeared in the brains of mice treated with normal saline, while the results of PTi-c-Te treatment were completely different. PTi-c-Te significantly inhibited tumor development and showed tiny intracranial tumor lesions. In addition, at the tissue level, apoptosis was mainly observed in tumor tissues of mice treated with PTi-c-Te; however, due to the lack of Ti-guided precise intracranial tumor targeting in the PSi-c-Te group, photodynamic therapy caused damage to both normal and tumor tissues. In summary, the photodynamic therapy strategy guided by the modular engineered adaptive nanoplatform (PTi-c-Te nanoplatform) disclosed in the present invention can achieve effective and safe photoguided therapy without complex imaging guidance or skilled operation.

[0048] The following is a specific example of the use of the modular engineered adaptive nano-platform (PTi-c-Te nano-platform) for drug delivery disclosed in the present invention: Eighteen mice bearing intracranial tumors were constructed, all of which were BALB / c athymic nude mice, about 6 weeks old, female; tumor cells were injected into the bregma, 1 mm lateral, 0.5 mm in front, and 3.6 mm deep; Efficacy criteria: (1) Evaluate the therapeutic effect by intracranial tumor volume; (2) Safety was assessed through weight changes and blood routine tests; Treatment: The drug delivery therapeutic efficacy of the modular engineered adaptive nanoplatform prepared by the present invention and the different nanoplatforms of Comparative Examples 1 to 3 was evaluated by nude mice carrying intracranial tumors. In the first week, normal saline, TMZ and SAN@TMZ (equivalent TMZ dose of 3.27 mg / kg) were intravenously injected every day for 3 consecutive days; in the second week, treatment was performed once every other day; starting from the third week, treatment was performed once a week; the size of the intracranial tumor was monitored using a nuclear magnetic resonance imaging system (BioSpec 94 / 30, Bruker) on days 0, 6, 14, 32 and 46; two days after the end of the treatment, retroorbital blood samples (30 μL) were collected from the mice, and blood tests were performed using an automatic blood analyzer (pocH-100iV Diff, Sysmex); subsequently, the weight changes of the mice were continuously monitored until the mice died naturally or their weight decreased continuously by 20% compared with the initial value.

[0049] Treatment results: Figure 2 This is the result of SGIPi-based chemotherapy. As can be seen from the figure, the intracranial tumors of mice in the saline group deteriorated rapidly, and the late stage was accompanied by rickets and sudden weight loss. Although the temozolomide treatment group effectively inhibited tumor growth during the treatment, the tumor progressed rapidly after drug withdrawal, and the mice died within two weeks due to the progression of intracranial tumors. In contrast, the adaptive nanoplatform treatment group showed significant advantages, not only preventing tumor progression, but even causing the tumor to gradually disappear within 30 days after drug withdrawal, and the fifth magnetic resonance imaging scan could no longer detect the tumor. All mice in the adaptive nanoplatform group survived healthily for more than 90 days (equivalent to 10.1 years in humans), during which time their weight continued to increase, and there was no common side effect of weight loss in temozolomide treatment, nor was there any blood toxicity such as leukopenia and thrombocytopenia, which further confirmed the mitigating effect of the adaptive nanoplatform on the blood toxicity of temozolomide.

[0050] Figure 3 Schematic diagram of modular construction of different nanoplatforms. From the figure, it can be seen that different modules can be arbitrarily combined to prepare adaptive nanoplatforms and their corresponding controls.

[0051] In summary, the chemotherapy drug delivery strategy of the modular engineered adaptive nanoplatform (PTi-c-Te nanoplatform) disclosed in the present invention not only significantly reduces the side effects of chemotherapy, but also achieves the complete eradication of intracranial tumors, bringing new hope for the treatment of glioma patients.

[0052] The above contents are only for explaining the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A method for preparing a modular engineered adaptive nanoplatform, characterized in that: The following steps are involved: PTi nanoparticles and PEG- Bis -Cys-CHO polymers were mixed, Te was added after stirring, and ultrafiltration centrifugation purification was performed after continuous stirring to obtain a modular engineered adaptive nano-platform.

2. The method for preparing a modular engineered adaptive nanoplatform according to claim 1, characterized in that: The PTi nanoparticles, PEG- Bis The usage ratio of -Cys-CHO polymer and Te is (350~445)μL: (5~100)μL: (5~100)μL.

3. The method for preparing a modular engineered adaptive nanoplatform according to claim 1, characterized in that: The stirring is carried out under a nitrogen protection environment; the stirring time is 12 to 24 hours; The continuous stirring time is 10 to 12 hours; The molecular weight cut-off of the ultrafiltration centrifugation purification process is 7000 Da.

4. The method for preparing a modular engineered adaptive nanoplatform according to claim 1, characterized in that: The PEG- Bis -Cys-CHO polymer is prepared by: PEG- Bis -Cys(Trt)-CHO polymer was dissolved in dichloromethane, and nitrogen was continuously introduced under ice bath conditions to form a mixed system; Trifluoroacetic acid, and triisopropylsilane were added to the mixed system in sequence, and the mixture was stirred and then post-treated to obtain PEG- Bis -Cys-CHO polymer.

5. The method for preparing a modular engineered adaptive nanoplatform according to claim 4, characterized in that: The PEG- Bis The usage ratio of -Cys(Trt)-CHO polymer, dichloromethane, trifluoroacetic acid, and triisopropylsilane is 300 mg: 6~10 mL: 670~1117 μL: 300~500 μL.

6. The method for preparing a modular engineered adaptive nanoplatform according to claim 4, characterized in that: The PEG- Bis The preparation method of the -Cys(Trt)-CHO polymer comprises: S1: O,O′-bis(2-aminoethyl)polyethylene glycol, Fmoc-Cys(Trt)-OH and dichloromethane are mixed to obtain a reaction mixture; anhydrous dichloromethane containing dicyclohexylcarbodiimide is added dropwise to the reaction mixture under ice bath conditions to react, and PEG- Bis -Fmoc-Cys(Trt) polymer; S2: PEG- Bis -Fmoc-Cys(Trt) polymer was dissolved in the mixed solvent and stirred to obtain PEG- Bis -Cys(Trt) polymer; S3: 4-Carboxybenzaldehyde, 1H-benzotriazol-1-yloxytripyrrolidino hexafluorophosphate and N,N-diisopropylethylamine were dissolved in dichloromethane, followed by the addition of PEG- Bis -Cys(Trt) polymer, and then stirred to obtain PEG- Bis -Cys(Trt)-CHO polymer.

7. The method for preparing a modular engineered adaptive nanoplatform according to claim 6, characterized in that: In S1, the amount ratio of the O,O′-bis(2-aminoethyl)polyethylene glycol, Fmoc-Cys(Trt)-OH, dichloromethane and anhydrous dichloromethane containing dicyclohexylcarbodiimide is 0.5-1 g: 484-968 mg: 15-30 mL: 15-20 mL; the content of dicyclohexylcarbodiimide in the anhydrous dichloromethane containing dicyclohexylcarbodiimide is 173 mg / 2 mL; In S2, PEG- Bis -Fmoc-Cys (Trt) polymer and mixed solvent are used in a ratio of 500-1000 mg: 1-2 mL; the mixed solvent is composed of 4-methylpiperidine and dimethylformamide; the volume ratio of 4-methylpiperidine and dimethylformamide is 1:4; In S3, 4-carboxybenzaldehyde, 1H-benzotriazol-1-yloxytripyrrolidino hexafluorophosphate, N,N-diisopropylethylamine, dichloromethane and PEG- Bis -Cys (Trt) polymer dosage ratio is 40~70 mg: 138~276 mg: 44~88 μL: 8~20 mL: 5~10 mL; the PEG- Bis -Cys(Trt) polymers in PEG- Bis The content of -Cys(Trt) polymer was 323 mg / 5 mL.

8. The method for preparing a modular engineered adaptive nanoplatform according to claim 1, characterized in that: The preparation method of the PTi nanoparticles is: The PTi monomer is dissolved in methanol and stirred to obtain a PTi monomer solution; the PTi monomer solution is dropped into deionized water under stirring, and the obtained mixed solution is subjected to ultrafiltration and centrifugation to obtain PTi nanoparticles; The usage ratio of the PTi monomer, methanol and deionized water is 5 mg:400 μL:1.5 mL.

9. A modular engineered adaptive nanoplatform, characterized in that: The method is prepared by any one of claims 1 to 9.

10. Use of the modular engineered adaptive nanoplatform according to claim 9 in anti-brain tumor drugs.

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