Preparation method of responsive nano-drug for treating colorectal cancer based on metformin
By reacting metformin with terephthaldehyde to form intermediates and assembled with polyethyleneimine and hyaluronic acid to form nanodrugs, combining antibacterial and antitumor drugs, the problem of limited efficacy of colorectal cancer chemotherapy is solved, and tumor reversal is achieved Effects of immunosuppressing the microenvironment and enhancing anti-tumor efficacy.
Patent Information
- Application Number
- CN202411604462.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-12
- Publication Date
- 2025-01-03
AI Technical Summary
The chemotherapy effect of colorectal cancer is limited, mainly because the high abundance of Floranus in tumor sites is enriched to inhibit the host's immune system, resulting in tumor immunosuppression microenvironment. The existing platinum anti-cancer drugs have a toxic effect on tumor cells and are not suitable for Normal cells also have toxic side effects.
By reacting metformin with terephthaldehyde to form intermediates, grafted onto polyethyleneimine and amidated, assembled with hyaluronic acid to form MPLO@HA nanodrugs, combining antibacterial and antitumor drugs, it reverses the tumor immunosuppression microenvironment , enhance anti-tumor efficacy and reduce chemotherapy drug dosage.
It significantly improves the therapeutic effect of colorectal cancer, enhances anti-tumor efficacy by reversing the tumor immunosuppression microenvironment, and achieves better cytotoxicity at low doses, reducing toxic and side effects on normal tissues.
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Figure CN119236094A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the field of biomedical nanomaterials, and in particular, relates to a method for preparing a responsive nanomedicine for treating colorectal cancer based on metformin. Background Art
[0002] The treatment of colorectal cancer has made great progress with the development of science and technology, but it still ranks third in the world as the most diagnosed cancer and the second leading cause of cancer-related deaths worldwide. In patients with recurrent cancer, the high abundance of Fusobacterium nucleatum at the tumor site affects the host's immune system, inhibiting the body's immune surveillance and immune clearance by reducing tumor immune cell infiltration and activation. This allows tumor cells to grow and spread in the intestine, promote tumor development and affect the tumor microenvironment, resulting in limited chemotherapy efficacy. Effective elimination of Fusobacterium nucleatum, improving chemotherapy efficacy, and improving the tumor immune microenvironment are essential to enhance the treatment of colorectal cancer. Most platinum-based anticancer drugs are toxic to tumor cells and can be used to treat cancer. Generally, increasing the dose of anticancer drugs will kill more tumor cells, but this will also aggravate the toxic side effects on normal cells. Understanding the anti-tumor mechanism of metformin and its regulatory effects on different cells in the tumor microenvironment will help promote the development and application of metformin as an anti-tumor drug to achieve better therapeutic effects. In addition, metformin can be used in combination with other drugs to achieve synergistic cancer treatment, thereby reducing the dose of chemotherapy drugs such as oxaliplatin and reducing toxic side effects on normal tissues.
[0003] The present invention generates a metformin intermediate (MA) through a Schiff base reaction of metformin (Met) and p-APA, and then synthesizes a monocarboxylic oxaliplatin (OxPt-COOH); on this basis, the metformin intermediate is grafted onto polyethyleneimine (PEI), and then the monocarboxylic oxaliplatin and lauric acid (LA) are grafted by an amidation reaction to obtain a compound MA-PEI-LA-OxPt (MPLO); finally, MPLO is composited with hyaluronic acid (HA) through electrostatic action to assemble into a nano drug MPLO@HA. This MPLO@HA nano drug can, on the one hand, synergistically enhance chemotherapy, reduce the dosage of chemotherapy drugs, and limit toxic side effects; on the other hand, it can effectively eliminate Fusobacterium nucleatum and reverse the tumor immunosuppressive microenvironment, thereby significantly improving the therapeutic effect of colorectal cancer. It has shown great application prospects in the biological field. Summary of the invention
[0004] The purpose of the present invention is to provide a method for preparing a responsive nanomedicine based on metformin for the treatment of colorectal cancer. A new type of environmentally responsive MPLO@HA nanomedicine is synthesized and assembled, which combines metformin, antibacterial drugs and anti-tumor chemotherapy drugs. The antibacterial effect and anti-tumor efficacy are effectively enhanced through synergistic effects, which significantly reverses the tumor immunosuppressive microenvironment, thereby inhibiting tumor growth, and providing a new strategy for the treatment of colorectal cancer.
[0005] The technical purpose of the present invention is achieved through the following technical solutions.
[0006] A method for preparing a responsive nanomedicine for treating colorectal cancer based on metformin, characterized in that MPLO is dissolved in ultrapure water or phosphate buffer solution at 0.05-0.5 mg / mL, and then HA is added at a mass ratio of 1:(1-5) according to the amount of MPLO, and after standing for 10-60 minutes, dialyzed for 4-10 hours to obtain the MPLO@HA nanomedicine.
[0007] The synthesis method of the above-mentioned metformin intermediate (MA) is as follows:
[0008] The terephthalaldehyde and metformin hydrochloride are reacted to generate a metformin intermediate. First, terephthalaldehyde and metformin hydrochloride are weighed and dissolved in methanol at a molar ratio of 1: (1-2), and reacted in a dark environment at 30-60°C under a nitrogen atmosphere for 18-36 hours. After the reaction is completed, the reaction solution is cooled to room temperature and purified by column chromatography. The sample is dry loaded, with silica gel as the stationary phase, ethyl acetate and n-hexane mixed in a volume ratio of 1: (1-20) as the mobile phase, and the metformin intermediate (MA) is obtained after evaporating the solvent. Its structural formula is as follows:
[0009]
[0010] The synthesis method of the above monocarboxyl oxaliplatin (OxPt-COOH) is as follows:
[0011] Dissolve 1 to 3 mmoles of oxaliplatin in acetic acid, and add 0.1 to 0.5 mL, 0.1 to 0.5 mL, and 0.5 to 1 mL of hydrogen peroxide every 10 to 60 minutes. After reacting at room temperature in the dark for 12 to 18 hours, remove the acetic acid by rotary evaporation, and then use liquid preparative chromatography for separation and purification. Silica gel is used as the stationary phase, and methanol and ethyl acetate are mixed in a volume ratio of 1: (1 to 5) as the mobile phase to finally obtain a white powdery compound. The above compound and succinic anhydride are weighed and dissolved in anhydrous N, N-dimethylformamide in a molar ratio of 1: (1 to 3), react at 40-60°C in the dark for 12 to 18 hours, and then the solvent is removed by rotary evaporation. The obtained product is transferred to acetone and centrifuged. The supernatant after centrifugation is precipitated with ice ether to obtain a white precipitate, which is dried in a vacuum drying oven to obtain monocarboxylic oxaliplatin (OxPt-COOH). Its structural formula is as follows:
[0012]
[0013] The synthesis method of the above MA-PEI-LA-OxPt (MPLO) is as follows:
[0014] The metformin intermediate and polyethyleneimine are weighed and dissolved in methanol in a mass ratio of 1: (1-2), and reacted at 40-80° C. for 1-4 hours under light-proof conditions to obtain solution 1; lauric acid and monocarboxy oxaliplatin are weighed and dissolved in methanol in a mass ratio of 1: (1-4), and 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride is weighed and added in a mass ratio of 1: (1-6) to lauric acid. 1-propyl) carbodiimide hydrochloride is activated at room temperature in the dark for 1-2 hours, and then N-hydroxysuccinimide is weighed and added in a mass ratio of lauric acid to N-hydroxysuccinimide of 1: (1-5) and activated at room temperature in the dark for 1-2 hours to obtain solution 2; solution 2 is slowly dripped into solution 1, and reacted at room temperature in the dark for 18-30 hours. After the reaction is completed, it is precipitated with ice ether and centrifuged, and the crude product is dissolved in ultrapure water, dialyzed for more than 3 days and freeze-dried to obtain MPLO. Its structural formula is as follows:
[0015]
[0016] Wherein, n is the degree of polymerization of polyethyleneimine, and its value is 10-300.
[0017] Compared with the existing technology, the present invention uses metformin, terephthalaldehyde, oxaliplatin, polyethyleneimine, lauric acid and hyaluronic acid as raw materials to synthesize and assemble a MPLO@HA nanodrug. This innovative nanodrug integrates metformin, highly effective antibacterial drugs and advanced anti-tumor chemotherapy drugs. With its unique synergistic mechanism, it not only greatly enhances the antibacterial properties, but also significantly improves the anti-tumor treatment effect. More importantly, it can effectively reverse the immunosuppressive microenvironment inside the tumor, opening up a new way to curb tumor growth. This achievement provides a new strategy for the treatment of colorectal cancer, indicating that it has broad application potential and prospects in the biological field.
[0018] The advantages of the present invention are: (1) the raw materials of the present invention are easily available, and the synthesis and preparation methods are simple; (2) the MPLO@HA nanomedicine has a stable and uniform particle size; (3) the MPLO@HA nanomedicine has good biocompatibility, can inhibit the proliferation of colorectal cancer cells, and promote their apoptosis; (4) the metformin in the MPLO@HA nanomedicine can further enhance the sensitivity of cancer cells to the chemotherapy drug oxaliplatin, thereby showing higher cytotoxicity and achieving better anti-tumor effects at low concentrations; (5) the MPLO@HA nanomedicine has good antibacterial properties, can effectively eliminate Fusobacterium nucleatum, reverse the tumor immunosuppressive microenvironment, and improve the therapeutic effect of colorectal cancer. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Figure 1 It is the nuclear magnetic spectrum of the metformin intermediate (MA) prepared by the present invention.
[0020] Figure 2 The figure is the nuclear magnetic resonance spectrum of monocarboxyl oxaliplatin (OxPt-COOH) prepared by the present invention.
[0021] Figure 3 It is the nuclear magnetic spectrum of MA-PEI-LA-OxPt (MPLO) prepared by the present invention.
[0022] Figure 4 It is a schematic diagram of the construction of the MPLO@HA nanomedicine prepared by the present invention.
[0023] Figure 5 This is a particle size distribution diagram of the MPLO@HA nanomedicine prepared by the present invention.
[0024] Figure 6 This is a diagram showing the in vivo anti-tumor effect of the MPLO@HA nanomedicine prepared by the present invention in a mouse tumor model. DETAILED DESCRIPTION
[0025] The technical solution of the present invention is further described below in conjunction with specific embodiments, but the scope of the present invention is not limited thereto.
[0026] The nuclear magnetic resonance spectrometer was used to perform the nuclear magnetic hydrogen spectrum test, using deuterated water, deuterated chloroform and deuterated methanol as solvents, and the test was performed at room temperature and analyzed by software. The nuclear magnetic hydrogen spectrum proved that all compounds were successfully synthesized. The dynamic light scattering instrument was used to characterize the particle size distribution of MPLO@HA nanomedicine.
[0027] Example 1
[0028] (1) The synthesis method of metformin intermediate (MA) is as follows:
[0029] Weigh terephthalaldehyde (5.40 g) and metformin hydrochloride (6.67 g) in a molar ratio of 1:1 and dissolve in 500 mL of methanol. React for 18 hours in a dark environment at 30°C under a nitrogen atmosphere. After the reaction, cool the reaction solution to room temperature and purify it by column chromatography. Dry loading, with silica gel as the stationary phase and ethyl acetate and n-hexane mixed in a volume ratio of 1:1 as the mobile phase, evaporate the solvent to obtain metformin intermediate (MA). Its structural formula is as follows:
[0030]
[0031] The H NMR spectrum is attached. Figure 1 As shown, it is proved that the metformin intermediate (MA) was successfully synthesized.
[0032] (2) The synthesis method of monocarboxy oxaliplatin (OxPt-COOH) is as follows:
[0033] Dissolve 1 mmol of oxaliplatin (400 mg) in 20 mL of acetic acid, and add 0.1 mL, 0.1 mL, and 0.5 mL of hydrogen peroxide every 10 minutes. After reacting in the dark at room temperature for 12 hours, remove the acetic acid by rotary evaporation, and then use liquid preparative chromatography for separation and purification. Silica gel is used as the stationary phase, and methanol and ethyl acetate are mixed in a volume ratio of 1:1 as the mobile phase to finally obtain a white powdery compound. The above compound (120 mg) and succinic anhydride (26 mg) are dissolved in 10 mL of anhydrous N, N-dimethylformamide in a molar ratio of 1:1. After reacting at 40°C for 12 hours in the dark, the solvent is removed by rotary evaporation, and the obtained product is transferred to acetone and centrifuged. The supernatant after centrifugation is precipitated with ice ether to obtain a white precipitate, which is dried in a vacuum drying oven to obtain monocarboxylic oxaliplatin (OxPt-COOH). Its structural formula is as follows:
[0034]
[0035] The H NMR spectrum is attached. Figure 2As shown, it was proved that monocarboxy oxaliplatin (OxPt-COOH) was successfully synthesized.
[0036] (3) The synthesis method of MA-PEI-LA-OxPt (MPLO) is as follows:
[0037] Metformin intermediate (400 mg) and polyethyleneimine (400 mg) were weighed in a mass ratio of 1:1 and dissolved in 20 mL of methanol. The mixture was reacted at 40°C for 1 hour in a light-proof condition to obtain solution 1. Lauric acid (200 mg) and monocarboxy oxaliplatin (200 mg) were weighed in a mass ratio of 1:1 and dissolved in 10 mL of methanol. 1-Ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride was weighed and added in a mass ratio of 1:1 between lauric acid and 1-Ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride. -dimethylaminopropyl) carbodiimide hydrochloride (200 mg) was activated at room temperature in the dark for 1 hour, and then N-hydroxysuccinimide (200 mg) was weighed and added at a mass ratio of lauric acid to N-hydroxysuccinimide of 1:1, and the activation was continued at room temperature in the dark for 1 hour to obtain solution 2; solution 2 was slowly dripped into solution 1, and the reaction was carried out at room temperature in the dark for 18 hours. After the reaction was completed, it was precipitated with ice ether and centrifuged, and the crude product was dissolved in ultrapure water, dialyzed for 3 days and freeze-dried to obtain MPLO. Its structural formula is as follows:
[0038]
[0039] Here, n is the degree of polymerization of polyethyleneimine, which is 10.
[0040] The H NMR spectrum is attached. Figure 3 As shown, it was proved that MA-PEI-LA-OxPt(MPLO) was successfully synthesized.
[0041] (4) The preparation method of MPLO@HA nanomedicine is as follows:
[0042] MPLO was dissolved in 10 mL ultrapure water at 0.05 mg / mL, and HA (0.5 mg) was added at a mass ratio of MPLO to HA of 1:1. After standing for 10 minutes, the mixture was dialyzed for 4 hours to obtain the MPLO@HA nanomedicine. Figure 4 As shown in the figure, it is a schematic diagram of the construction of MPLO@HA nanomedicine. Figure 5 As shown in the figure, the particle size of MPLO@HA nanomedicine measured by dynamic light scattering is 182.4nm, indicating that HA is successfully coated on MPLO and the particle size is uniform. Figure 6 As shown in the figure, "+" and "-" represent mouse tumor cells incubated in the presence or absence of Fusobacterium nucleatum, respectively. Compared with different control groups, MPLO@HA nanomedicine has the most obvious inhibitory effect on mouse tumor growth, with a tumor volume of only 250mm 3, indicating that MPLO@HA nanomedicine has excellent anti-tumor efficacy.
[0043] Example 2
[0044] (1) The synthesis method of metformin intermediate (MA) is as follows:
[0045] Weigh terephthalaldehyde (5.40 g) and metformin hydrochloride (10.00 g) at a molar ratio of 1:1.5 and dissolve in 500 mL of methanol. React for 27 hours in a dark environment at 45°C under a nitrogen atmosphere. After the reaction, cool the reaction solution to room temperature and purify it by column chromatography. Dry loading, with silica gel as the stationary phase and ethyl acetate and n-hexane mixed in a volume ratio of 1:10 as the mobile phase, evaporate the solvent to obtain metformin intermediate (MA). Its structural formula is as follows:
[0046]
[0047] The H NMR spectrum is attached. Figure 1 As shown, it is proved that the metformin intermediate (MA) was successfully synthesized.
[0048] (2) The synthesis method of monocarboxy oxaliplatin (OxPt-COOH) is as follows:
[0049] 2 mmol of oxaliplatin (800 mg) was dissolved in 20 mL of acetic acid, and 0.3 mL, 0.3 mL, and 0.8 mL of hydrogen peroxide were added in sequence every 30 minutes. After reacting in the dark at room temperature for 15 hours, the acetic acid was removed by rotary evaporation, and then separated and purified using a liquid preparative chromatograph. Silica gel was used as the stationary phase, and methanol and ethyl acetate were mixed in a volume ratio of 1:3 as the mobile phase, and a white powdery compound was finally obtained. The above compound (120 mg) and succinic anhydride (52 mg) were dissolved in 10 mL of anhydrous N, N-dimethylformamide in a molar ratio of 1:2, and reacted at 50 ° C for 15 hours under dark conditions. The solvent was removed by rotary evaporation, and the obtained product was transferred to acetone and centrifuged. The supernatant after centrifugation was precipitated with ice ether to obtain a white precipitate, which was dried in a vacuum drying oven to obtain monocarboxylic oxaliplatin (OxPt-COOH). Its structural formula is as follows:
[0050]
[0051] The H NMR spectrum is attached. Figure 2 As shown, it was proved that monocarboxy oxaliplatin (OxPt-COOH) was successfully synthesized.
[0052] (3) The synthesis method of MA-PEI-LA-OxPt (MPLO) is as follows:
[0053] Metformin intermediate (400 mg) and polyethyleneimine (600 mg) were weighed in a mass ratio of 1:1.5 and dissolved in 20 mL of methanol. The mixture was reacted at 60°C for 2 hours under light-proof conditions to obtain solution 1. Lauric acid (200 mg) and monocarboxy oxaliplatin (600 mg) were weighed in a mass ratio of 1:3 and dissolved in 10 mL of methanol. 1-Ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride was weighed and added in a mass ratio of 1:4 between lauric acid and 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride. Dimethylaminopropyl) carbodiimide hydrochloride (800 mg) was activated at room temperature in the dark for 1.5 hours, and then N-hydroxysuccinimide (800 mg) was weighed and added at a mass ratio of lauric acid to N-hydroxysuccinimide of 1:4, and the activation was continued at room temperature in the dark for 1.5 hours to obtain solution 2; solution 2 was slowly dripped into solution 1, and the reaction was carried out at room temperature in the dark for 24 hours. After the reaction was completed, it was precipitated with ice ether and centrifuged, and the crude product was dissolved in ultrapure water, dialyzed for 4 days and freeze-dried to obtain MPLO. Its structural formula is as follows:
[0054]
[0055] Wherein, n is the degree of polymerization of polyethyleneimine, and its value is 150.
[0056] The H NMR spectrum is attached. Figure 3 As shown, it was proved that MA-PEI-LA-OxPt(MPLO) was successfully synthesized.
[0057] (4) The preparation method of MPLO@HA nanomedicine is as follows:
[0058] MPLO was dissolved in 10 mL of phosphate buffer solution at 0.1 mg / mL, and HA (3 mg) was added according to the mass ratio of MPLO to HA of 1:3. After standing for 30 minutes, the mixture was dialyzed for 6 hours to obtain the MPLO@HA nanomedicine. The particle size of the MPLO@HA nanomedicine measured by dynamic light scattering was 173.5 nm, indicating that HA was successfully coated on MPLO and the particle size was uniform. Compared with different control groups, the MPLO@HA nanomedicine had the most obvious inhibitory effect on mouse tumor growth, with a tumor volume of only 263 mm 3 , indicating that MPLO@HA nanomedicine has excellent anti-tumor efficacy.
[0059] Example 3
[0060] (1) The synthesis method of metformin intermediate (MA) is as follows:
[0061] Weigh terephthalaldehyde (5.40 g) and metformin hydrochloride (13.34 g) in a molar ratio of 1:2 and dissolve in 500 mL of methanol. React in a dark environment at 60°C under a nitrogen atmosphere for 36 hours. After the reaction, cool the reaction solution to room temperature and purify it by column chromatography. Dry loading, with silica gel as the stationary phase and ethyl acetate and n-hexane mixed in a volume ratio of 1:20 as the mobile phase, evaporate the solvent to obtain metformin intermediate (MA). Its structural formula is as follows:
[0062]
[0063] The H NMR spectrum is attached. Figure 1 As shown, it is proved that the metformin intermediate (MA) was successfully synthesized.
[0064] (2) The synthesis method of monocarboxy oxaliplatin (OxPt-COOH) is as follows:
[0065] 3 mmol of oxaliplatin (1200 mg) was dissolved in 20 mL of acetic acid, and 0.5 mL, 0.5 mL, and 1 mL of hydrogen peroxide were added in sequence every 60 minutes. After reacting at room temperature in the dark for 18 hours, the acetic acid was removed by rotary evaporation, and then separated and purified using a liquid preparative chromatograph. Silica gel was used as the stationary phase, and methanol and ethyl acetate were mixed in a volume ratio of 1:5 as the mobile phase, and a white powdery compound was finally obtained. The above compound (120 mg) and succinic anhydride (78 mg) were dissolved in 10 mL of anhydrous N, N-dimethylformamide in a molar ratio of 1:3, and reacted at 60 ° C for 18 hours in the dark, and the solvent was removed by rotary evaporation. The obtained product was transferred to acetone and centrifuged. The supernatant after centrifugation was precipitated with ice ether to obtain a white precipitate, which was dried in a vacuum drying oven to obtain monocarboxylic oxaliplatin (OxPt-COOH). Its structural formula is as follows:
[0066]
[0067] The H NMR spectrum is attached. Figure 2 As shown, it was proved that monocarboxy oxaliplatin (OxPt-COOH) was successfully synthesized.
[0068] (3) The synthesis method of MA-PEI-LA-OxPt (MPLO) is as follows:
[0069] Metformin intermediate (400 mg) and polyethyleneimine (800 mg) were weighed in a mass ratio of 1:2 and dissolved in 20 mL of methanol. The mixture was reacted at 80°C for 4 hours under light-proof conditions to obtain solution 1. Lauric acid (200 mg) and monocarboxy oxaliplatin (800 mg) were weighed in a mass ratio of 1:4 and dissolved in 10 mL of methanol. 1-Ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride was weighed and added in a mass ratio of 1:6 between lauric acid and 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride. Dimethylaminopropyl) carbodiimide hydrochloride (1200 mg) was activated at room temperature in the dark for 2 hours, and then N-hydroxysuccinimide (1000 mg) was weighed and added at a mass ratio of lauric acid to N-hydroxysuccinimide of 1:5, and the activation was continued at room temperature in the dark for 2 hours to obtain solution 2; solution 2 was slowly dripped into solution 1, and the reaction was carried out at room temperature in the dark for 30 hours. After the reaction was completed, it was precipitated with ice ether and centrifuged, and the crude product was dissolved in ultrapure water, dialyzed for 3 days and freeze-dried to obtain MPLO. Its structural formula is as follows:
[0070]
[0071] Wherein, n is the degree of polymerization of polyethyleneimine, and its value is 300.
[0072] The H NMR spectrum is attached. Figure 3 As shown, it was proved that MA-PEI-LA-OxPt(MPLO) was successfully synthesized.
[0073] (4) The preparation method of MPLO@HA nanomedicine is as follows:
[0074] MPLO was dissolved in 10 mL of ultrapure water at 0.5 mg / mL, and HA (25 mg) was added at a mass ratio of 1:5 between MPLO and HA. After standing for 60 minutes, the mixture was dialyzed for 10 hours to obtain the MPLO@HA nanomedicine. The particle size of the MPLO@HA nanomedicine measured by dynamic light scattering was 179.1 nm, indicating that HA was successfully coated on MPLO and the particle size was uniform. Compared with different control groups, the MPLO@HA nanomedicine had the most obvious inhibitory effect on mouse tumor growth, with a tumor volume of only 258 mm 3 , indicating that MPLO@HA nanomedicine has excellent anti-tumor efficacy.
[0075] According to the content of the present invention, the process parameters can be adjusted to achieve the preparation of nano drugs, and the performance shown by the test is basically consistent with the present invention. The above is an exemplary description of the present invention. Without departing from the core of the present invention, any simple deformation, modification or equivalent replacement that can be made by other technicians in this field without spending creative labor falls within the protection scope of the present invention.
Claims
1. A method for preparing a responsive nanomedicine for treating colorectal cancer based on metformin, characterized in that: A metformin intermediate (MA) was generated by the Schiff base reaction of metformin (Met) and p-APA, and then a monocarboxylic oxaliplatin (OxPt-COOH) was synthesized; on this basis, the metformin intermediate was grafted onto polyethyleneimine (PEI), and then amidation reaction was carried out to graft monocarboxylic oxaliplatin and lauric acid (LA) to obtain the compound MA-PEI-LA-OxPt (MPLO); finally, MPLO was composited with hyaluronic acid (HA) through electrostatic action to assemble into the nanodrug MPLO@HA. The structural formula of the metformin intermediate (MA) is shown below: The structural formula of monocarboxy oxaliplatin (OxPt-COOH) is as follows: The structural formula of MA-PEI-LA-OxPt (MPLO) is as follows: Wherein, n is the degree of polymerization of polyethyleneimine, and its value is 10-300.
2. According to claim 1, a method for preparing a responsive nanomedicine for treating colorectal cancer based on metformin, characterized in that: The synthesis method of metformin intermediate (MA) is as follows: Terephthalaldehyde and metformin hydrochloride are reacted to generate a metformin intermediate; first, terephthalaldehyde and metformin hydrochloride are weighed and dissolved in methanol in a molar ratio of 1: (1-2), and reacted in a dark environment at 30-60° C. under a nitrogen atmosphere for 18-36 hours; after the reaction, the reaction solution is cooled to room temperature, purified by column chromatography, dry-loaded, silica gel as a stationary phase, ethyl acetate and n-hexane mixed in a volume ratio of 1: (1-20) as a mobile phase, and the solvent is evaporated to obtain a metformin intermediate (MA).
3. According to claim 1, a method for preparing a responsive nanomedicine for treating colorectal cancer based on metformin, characterized in that: The synthesis method of monocarboxy oxaliplatin (OxPt-COOH) is as follows: 1-3 mmol of oxaliplatin is dissolved in acetic acid, and 0.1-0.5 mL, 0.1-0.5 mL, and 0.5-1 mL of hydrogen peroxide are added in sequence every 10-60 minutes; after reacting in the dark for 12-18 hours at room temperature, the acetic acid is removed by rotary evaporation, and then separation and purification are performed using a liquid preparative chromatography; silica gel is used as the stationary phase, and methanol and ethyl acetate are mixed in a volume ratio of 1: (1-5) as the mobile phase to finally obtain a white powdery compound; the above compound and succinic anhydride are weighed and dissolved in anhydrous N, N-dimethylformamide in a molar ratio of 1: (1-3), reacted at 40-60° C. under dark conditions for 12-18 hours, and the solvent is removed by rotary evaporation, the obtained product is transferred to acetone and centrifuged, and the supernatant after centrifugation is precipitated with ice ether to obtain a white precipitate, which is dried in a vacuum drying oven to obtain monocarboxy oxaliplatin (OxPt-COOH).
4. According to claim 1, a method for preparing a responsive nanomedicine for treating colorectal cancer based on metformin, characterized in that: The synthesis method of MA-PEI-LA-OxPt (MPLO) is as follows: The metformin intermediate and polyethyleneimine were weighed and dissolved in methanol in a mass ratio of 1: (1-2), and reacted at 40-80° C. for 14 hours under light-proof conditions to obtain solution 1; lauric acid and monocarboxy oxaliplatin were weighed and dissolved in methanol in a mass ratio of 1: (1-4), and 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride was weighed and added in a mass ratio of 1: (1-6) to obtain solution 1; The mixture is stirred for 1 to 2 hours at room temperature in the dark with 2% propyl) carbodiimide hydrochloride, and then N-hydroxysuccinimide is weighed and added in a mass ratio of lauric acid to N-hydroxysuccinimide of 1:(1 to 5), and the mixture is further activated for 1 to 2 hours at room temperature in the dark to obtain solution 2; solution 2 is slowly dripped into solution 1, and the mixture is reacted at room temperature in the dark for 18 to 30 hours. After the reaction is completed, the mixture is precipitated with icy ether and centrifuged. The crude product is dissolved in ultrapure water, dialyzed for more than 3 days, and freeze-dried to obtain MPLO.
5. According to claim 1, a method for preparing a responsive nanomedicine for treating colorectal cancer based on metformin, characterized in that: The assembly method for preparing MPLO@HA nanomedicine is as follows: MPLO was dissolved in ultrapure water or phosphate buffer solution at 0.05-0.5 mg / mL, and HA was added at a mass ratio of 1:(1-5) according to the amount of MPLO. After standing for 10-60 minutes, the mixture was dialyzed for 4-10 hours to obtain MPLO@HA nanomedicine.
6. According to claim 1, a method for preparing a responsive nanomedicine for treating colorectal cancer based on metformin, characterized in that: Preparation of MPLO@HA nanomedicine for colorectal cancer treatment research.