Hydrolysis products of poly[α-cyanoacrylate], method for producing the same, and use thereof

Abstract

The present invention provides hydrolysis products of poly[α-cyanoacrylate], their preparation methods and uses, which belong to the field of medicinal chemistry. [Solution] The hydrolysis product of poly[α-cyanoacrylate] represented by the following chemical formula (1) is obtained. Poly[2-cyanoacrylic acid] is dispersed in water to form negatively charged microspheres, which are then used to obtain unloaded embolic microspheres. The particle size of these unloaded embolic microspheres can be adjusted to the micron range, and they have the deformability to pass through blood vessels with specific shapes, enabling them to reliably embolize blood vessels and prevent ectopic embolism due to detachment. Poly[2-carboxyacrylic acid] can be used to manufacture novel nano drug carriers, which can enhance the therapeutic effect of the loaded drug on diseased tissues and reduce the toxicity and side effects of the loaded drug on normal tissues. [Formula 1] TIFF2022547140000008.tif26115(1) "R is -CN or -COOH."

Description

Technical Field

[0001] The present invention belongs to the field of pharmaceutical chemistry, and more particularly relates to hydrolysis products of poly[α-cyanoacrylate], methods for their production and uses.

Background Art

[0002] Although intravascular embolism is generally considered to be avoided, for some blood vessels, good therapeutic effects can be obtained by selectively embolizing them. In recent years, with the development of medical technology, it has become possible to inject a vascular occlusive agent into related arteries by catheterization to treat some diseases that are difficult to control by surgery or drugs, especially tumors and gastric fundus varix-like swellings. Such a technique is medically called selective vascular embolization. Transcatheter arterial embolization was first used in the 1970s for the treatment of prostate puncture biopsy, prostate bleeding after transurethral prostatectomy, and intractable hematuria caused by the prostate. In vascular embolization, it is necessary to use an embolic agent. In addition to natural embolic substances such as thrombus, mechanical embolization using a balloon, small metal balls, a spring tube, etc. can also be performed. Currently used embolic agents are classified into two types: solid and liquid, and some natural embolic agents are also classified as solid embolic agents.

[0003] There are many types of nanodrug carriers, among which liposomes have received particular attention. Liposomes are mainly composed of cholesterol and phospholipids, have a structure similar to cells, and can be used to carry drugs. Liposomes mainly have two problems. The first is how to carry drugs. The second is how to prevent liposomes from being phagocytosed and destroyed by the reticuloendothelial system and how to release drugs to the lesion tissue. Liposomes are relatively ideal drug carriers because they are low in toxicity, non-immunogenic, non-pyrogenic, and can be eliminated by normal metabolism. Current nanoliposome drugs are mainly manufactured by spontaneously carrying drugs through an ammonium ion gradient. For example, Doxil is a liquid doxorubicin nanoliposome. However, such doxorubicin nanoliposomes have a complicated manufacturing process, poor stability, and it is difficult to spontaneously release drugs to the tumor tissue site.

Summary of the Invention

Problems to be Solved by the Invention

[0004] An object of the present invention is to provide a hydrolysis product of poly[α-cyanoacrylate], a method for producing the same, and its use in order to solve the problems in the prior art.

Means for Solving the Problems

[0005] The technical means of the present invention are as follows. A hydrolysis product of poly[α-cyanoacrylate] represented by the following chemical formula.

[0006]

Chemical Formula

[0007]

Chemical formula

[0008] The present invention claims protection for the use of the hydrolysis product of the poly[α-cyanoacrylate]. Such use is to produce poly[2-cyanoacrylic acid] into non-supported embolization microspheres. Furthermore, the method for producing the non-supported embolization microspheres involves dispersing poly[2-cyanoacrylic acid] in water to form microspheres with a negative charge, thereby obtaining non-supported embolization microspheres. Furthermore, the non-supported embolization microspheres have a particle diameter of 1 μm or more and are deformable. Furthermore, the non-supported embolization microspheres can have their particle diameters adjusted within the micro-order range to adapt to vascular embolization targets with different vessel diameters, and also have the ability to deform to pass through narrow sections of blood vessels during embolization as needed, and can reliably embolize blood vessels to prevent ectopic embolization due to detachment.

[0009] In the present invention, non-supported embolization microspheres produced from poly[2-cyanoacrylic acid] are produced into drug-loaded embolization microspheres. Furthermore, the method for producing the drug-loaded embolization microspheres involves binding non-supported embolization microspheres with a drug having a positive charge to obtain drug-loaded embolization microspheres. Furthermore, the drug-loaded embolizing microspheres spontaneously carry (pH ≥ 7.4) and release (pH ≤ 6.5) drugs based on the principle of charge reversal. Furthermore, the drug-loaded embolizing microspheres can directly release drugs to the local lesion tissue in lesion tissues with high vascular permeability and low pH value. Since there is almost no systemic flow of the drug, the therapeutic effect of the drug on the local lesion tissue is enhanced, and the systemic toxicity and side effects of the drug are reduced.

[0010] More preferable manufacturing methods and uses are as follows. 1. Production of poly[2-cyanoacrylic acid] (1) Method 1 In physiological saline with a pH value of 2.0 - 4.0, a glucose solution of 5% or more, or a dextran solution of 5% or more, using a nonionic surfactant, such as a polyethylene glycol type nonionic surfactant, Tween surfactants, Span surfactants, or Poloxamer, etc., prepare an emulsion of α-cyanoacrylate or its vegetable oil solution. Next, adjust the pH value to 7.4 or more to accelerate the polymerization reaction to form a polymer of α-cyanoacrylate. Furthermore, under alkaline conditions, selectively hydrolyze the ester bond of the polymer so as to leave the cyano group. Under these alkaline conditions, the vegetable oil is saponified. Then, remove impurities by dialysis to obtain poly[2-cyanoacrylic acid].

[0011] The higher the content of the nonionic surfactant and the lower the usage amount of α-cyanoacrylate, the smaller the particle size of the emulsion. The degree of polymerization of poly[2-cyanoacrylic acid] can be controlled by the particle size of the α-cyanoacrylate emulsion. The smaller the particle size of the emulsion, the lower the degree of polymerization. Poly[2-cyanoacrylic acid] in different molecular weight ranges can be separated and produced by dialysis or gel permeation chromatography.

[0012] (2) Method 2 Dissolve α-cyanoacrylate in absolute ethanol, acetone or acetonitrile. Under the conditions of high-speed dispersion with a hard plastic disperser, gradually drop the absolute ethanol, acetonitrile or acetone solution of α-cyanoacrylate into acidic water and stir magnetically overnight. Collect the α-cyanoacrylate polymer precipitate by high-speed centrifugation. Furthermore, under alkaline conditions, selectively hydrolyze the ester bond of the polymer while leaving the cyano group. Then, remove impurities by dialysis to obtain poly[2-cyanoacrylic acid]. The degree of polymerization of poly[2-cyanoacrylic acid] can be controlled by the concentration of α-cyanoacrylate. The lower the concentration, the lower the degree of polymerization. Poly[2-cyanoacrylic acid] with different molecular weight ranges can be separated and produced by dialysis or gel permeation chromatography.

[0013] 2. Preparation of Poly[2-cyanoacrylic acid] Unsupported Plug Microspheres By controlling the polymerization time of poly[α-cyanoacrylate] or the concentration of α-cyanoacrylate, its degree of polymerization can be controlled, and the particle size of the unsupported plug microspheres can be controlled. Poly[2-cyanoacrylic acid] is rich in carboxyl groups. The unsupported plug microspheres have negatively charged carboxyl groups under alkaline conditions, and repulsion occurs between the negative charges. Therefore, the unsupported plug microspheres have elasticity and deformability.

[0014] (1) Method 1 Poly[2-cyanoacrylic acid] has a certain degree of surface activity and is easily soluble in absolute ethanol. By dispersing its ethanol solution in water, unsupported plug microspheres rich in carboxyl groups can be obtained. (2) Method 2 Poly[2-cyanoacrylic acid] has a certain degree of surface activity and is easily soluble in absolute ethanol. By dispersing its ethanol solution in water and further modifying a part of the carboxyl groups of poly[2-cyanoacrylic acid] with activated polyethylene glycol, non-supported embolizing microspheres with carboxyl groups modified can be obtained.

[0015] The polyethylene glycol bonded to the carboxyl group of the polymer can effectively prevent the reticuloendothelial system from rapidly phagocytosing and destroying poly[2-cyanoacrylic acid], which is the skeletal material of the non-supported embolizing microspheres. The unmodified carboxyl groups are used to spontaneously carry positively charged drugs. The optimal modification ratio of the carboxyl group is related to the drug loading amount and the type of drug. When the molecular weight of the drug is relatively large and the hydrophilicity is relatively low, the modification ratio of the carboxyl group is increased. When the molecular weight of the drug is relatively small and the hydrophilicity is relatively high, the modification ratio of the carboxyl group is decreased. Also, the modification ratio of the carboxyl group is related to individual differences and needs to be set to such an extent that the non-supported embolizing microspheres are not rapidly destroyed by the reticuloendothelial system. Therefore, the specific modification ratio of the carboxyl group and the molecular weight of the activated polyethylene glycol need to be specifically determined according to clinical requirements.

[0016] 3. Use of Poly[2-cyanoacrylic acid] Non-Supported Embolizing Microspheres The particle size of the poly[2-cyanoacrylic acid] non-supported embolizing microspheres can be adjusted according to clinical requirements. Also, the poly[2-cyanoacrylic acid] non-supported embolizing microspheres have elasticity and deformability. When the particle size is 8 μm or more, they can pass through narrow parts of specific blood vessels during embolization treatment, and can firmly adhere to the blood vessel wall and are not easily shed, and no foreign embolism occurs.

[0017] 4. Manufacture of Poly[2-cyanoacrylic acid] Drug-Loaded Embolizing Microspheres By binding poly[2-cyanoacrylic acid] non-supported embolizing microspheres with various positively charged drugs, various drug-loaded embolizing microspheres can be obtained.

[0018] 5. Use of Poly[2-cyanoacrylic acid] Drug-Loaded Embolic Microspheres The drug-loaded embolic microspheres can carry one or more positively charged drugs according to clinical requirements and be used for specific local embolization treatment. The drug-loaded embolic microspheres can release drugs directly into the local lesion tissue in lesion tissues with high vascular permeability and low pH value. Since there is almost no systemic flow of the drugs, the therapeutic effect of the drugs on the local lesion tissue is enhanced, and the systemic toxicity and side effects of the drugs are reduced. Poly[2-carboxyacrylic acid] represented by the following chemical formula, where R is -COOH.

[0019] [Chemical formula] The production method of poly[2-carboxyacrylic acid] is to first produce a polymer of α-cyanoacrylate, then hydrolyze the ester bond and cyano group of the polymer under alkaline conditions, and further remove impurities by dialysis to obtain poly[2-carboxyacrylic acid].

[0020] The present invention claims protection for the use of the hydrolysis product of the above poly[α-cyanoacrylate]. Such use is to produce poly[2-carboxyacrylic acid] into a nano-drug carrier. Furthermore, the production method of the nano-drug carrier is to modify a part of the carboxyl groups of poly[2-carboxyacrylic acid] with activated polyethylene glycol, and use the unmodified carboxyl groups to carry positively charged drugs. Due to the pH gradient, a novel nano-drug carrier with the function of spontaneously carrying (pH≥7.4) and releasing (pH≤6.5) positively charged drugs is obtained.

[0021] Furthermore, the production method of the nano-drug carrier is to encapsulate poly[2-carboxyacrylic acid] into liposomes, and due to the pH gradient, a novel nano-drug carrier, which is a novel nanoliposome with the function of spontaneously carrying (pH≥7.4) and releasing (pH≤6.5) positively charged drugs, is obtained. Furthermore, the nano drug carrier spontaneously carries and releases drugs based on the principle of charge reversal. Furthermore, the nano drug carrier targets and delivers drugs through the blood, accumulates in lesion tissues with high vascular permeability and low pH value, directly releases drugs to the lesion tissues, and hardly any drugs enter the normal tissues. Therefore, the therapeutic effect of the drugs carried on the lesion tissues is enhanced, and the toxicity and side effects on the normal tissues are reduced.

[0022] More preferable manufacturing methods and uses are as follows. 1. Preparation of poly[2-carboxyacrylic acid] (3) Method 1 In physiological saline with a pH value of 2.0 - 4.0, a glucose solution of 5% or more, or a dextran solution of 5% or more, using a non-ionic surfactant, such as a polyethylene glycol type non-ionic surfactant, a Tween type surfactant, a Span type surfactant, or a poloxamer, etc., prepare an emulsion of α-cyanoacrylate or its vegetable oil solution. Next, adjust the pH value to 7.4 or more to accelerate the polymerization reaction to form a polymer of α-cyanoacrylate. Furthermore, under alkaline conditions, hydrolyze the ester bond and cyano group of the polymer. Under this alkaline condition, the vegetable oil is saponified. Then, remove impurities by dialysis to obtain poly[2-carboxyacrylic acid].

[0023] The higher the content of the non-ionic surfactant and the lower the amount of α-cyanoacrylate used, the smaller the volume of the microemulsion. The degree of polymerization of poly[2-carboxyacrylic acid] can be controlled by the size of the α-cyanoacrylate microemulsion. The smaller the microemulsion, the lower the degree of polymerization. Poly[2-carboxyacrylic acid] with different molecular weight ranges can be separated and manufactured by dialysis or gel permeation chromatography.

[0024] (4) Method 2 Dissolve α-cyanoacrylate in absolute ethanol, acetone or acetonitrile. Under the conditions of high-speed dispersion with a rigid plastic disperser, gradually drop the absolute ethanol, acetonitrile or acetone solution of α-cyanoacrylate into acidic water and stir magnetically overnight. Collect the α-cyanoacrylate polymer precipitate by high-speed centrifugation. Furthermore, under alkaline conditions, hydrolyze the ester bond and cyano group of the polymer. Then, remove impurities by dialysis to obtain poly[2-carboxyacrylic acid]. The degree of polymerization of poly[2-carboxyacrylic acid] can be controlled by the concentration of α-cyanoacrylate. The lower the concentration, the lower the degree of polymerization. Poly[2-carboxyacrylic acid] with different molecular weight ranges can be separated and produced by dialysis or gel permeation chromatography.

[0025] 2. Preparation of poly[2-carboxyacrylic acid] nanodrug carriers (1) Method 1 By modifying a part of the carboxy groups of poly[2-carboxyacrylic acid] with activated polyethylene glycol, poly[2-carboxyacrylic acid] nanodrug carriers can be obtained. The polyethylene glycol bonded to the carboxy group of the polymer can effectively prevent the reticuloendothelial system from rapidly phagocytosing and destroying poly[2-carboxyacrylic acid], which is the skeletal material of the nanodrug carrier. The unmodified carboxy groups are used to spontaneously carry positively charged drugs. The optimal modification ratio of carboxy groups is related to the drug loading amount and the type of drug. When the molecular weight of the drug is relatively large and the hydrophilicity is relatively low, increase the modification ratio of carboxy groups. When the molecular weight of the drug is relatively small and the hydrophilicity is relatively high, lower the modification ratio of carboxy groups. Also, the modification ratio of carboxy groups is related to individual differences and needs to be set to such an extent that the nanodrug carrier is not rapidly destroyed by the reticuloendothelial system. Therefore, the specific modification ratio of carboxy groups and the molecular weight of activated polyethylene glycol need to be specifically determined according to clinical requirements.

[0026] (2) Method 2 Dissolve phospholipids, cholesterol, PEG2000 - DSPE, and poly[2 - carboxyacrylic acid] in absolute ethanol, and use the thin - film method to produce liposomes encapsulating poly[2 - carboxyacrylic acid] inside. By removing poly[2 - carboxyacrylic acid] on the outside of the liposomes through gel permeation chromatography, nanoliposomes encapsulating poly[2 - carboxyacrylic acid] can be obtained. Furthermore, by adjusting the pH value of the outer aqueous phase of the nanoliposomes to 7.4, the pH value gradient between the inside and outside of the liposomes reaches 5.0 or more, and a nanodrug carrier, which is a nanoliposome having the function of spontaneously carrying positively charged drugs, can be obtained.

[0027] According to the Henderson - Hasselbalch theory, a change of one pH unit results in a 10 - fold difference in the concentrations of the molecular - form drug and the ionic - form drug. When the pH value gradient between the inside and outside of the liposomes is 3.0, theoretically, a 1000 - fold difference in the concentrations of the molecular - form drug and the ionic - form drug occurs. Since the molecular - form drug is likely to bind to the bilayer membrane of the liposomes, the process of drug molecule transmembrane and internal movement is promoted. Poly[2 - carboxyacrylic acid] binds to positively charged drugs to form a precipitate. This can further promote the entry of positively charged drugs into the nanoliposomes and enhance the drug - carrying ability of the nanoliposomes.

[0028] 3. Use of the poly[2 - carboxyacrylic acid] nanodrug carrier The nanodrug carrier prepared using poly[2 - carboxyacrylic acid], based on the principle of charge reversal, spontaneously carries positively charged drugs via carboxyl groups under alkaline conditions, for example, at pH = 7.4, and conversely, spontaneously releases the carried positively charged drugs under acidic conditions, for example, at pH = 6.5. Normal tissues have low vascular permeability and a relatively high pH value (about 7.4). On the other hand, diseased tissues have high vascular permeability and a relatively low pH value (about 6.5). Therefore, after entering the blood circulation system, the nano-drug carrier gradually accumulates in the diseased tissue and releases the carried drug, thereby enhancing the therapeutic effect of the drug on the diseased tissue (except for prodrugs) and reducing the toxicity and side effects of the drug on normal tissues.

Advantages of the Invention

[0029] The beneficial effects of the present invention are as follows. (1) Provide a method for manufacturing a novel material which is poly[2-cyanoacrylic acid] rich in carboxyl groups. (2) Using poly[2-cyanoacrylic acid], novel non-supported embolization microspheres can be manufactured. (3) The novel non-supported embolization microspheres have adjustable particle diameters and the ability to deform and pass through narrow places. (4) Using the novel non-supported embolization microspheres, novel drug-loaded embolization microspheres can be manufactured. (5) The novel drug-loaded embolization microspheres can enhance the therapeutic effect of the carried drug on the local diseased tissue. (6) The novel drug-loaded embolization microspheres can reduce the systemic toxicity and side effects of the carried drug. (7) In the foreign DC-bead prior art (shown in Figure 1), it is necessary to use N-acryloyl-aminoacetaldehyde-dimethylacetal and butyl acetate, so it has high volatility, a large residue amount, is disadvantageous to the production environment, and has low safety. In the present invention, only α-cyanoacrylate, vegetable oil, glucose, physiological saline, non-ionic surfactant, activated polyethylene glycol, absolute ethanol, pure substances, etc. are used, so there is no residue of toxic substances, no pollution, the process is simple, the production cost is low, and the safety is high. (8) Foreign DC-beads have a relatively small number of anti-cancer drug-carrying molecules per unit volume. The drug-carrying embolization microspheres produced in the present invention are estimated from their chemical structure that approximately 50% of the carbon atoms in the molecular structure each have one carboxyl group negative charge. On the other hand, in DC-beads, approximately 20% of the carbon atoms in the molecule each have one carboxyl group negative charge. The drug-carrying embolization microspheres produced in the present invention have a significantly higher total negative charge per unit mass than DC-beads, and the drug-carrying ability is significantly improved. (9) Foreign DC-beads have relatively strong acidic sulfonic acid groups and have a weak ability to selectively release drugs near tumor tissues. The drug-carrying embolization microspheres produced in the present invention have relatively weak acidic carboxyl groups, and the drug release rates are different under different pH value conditions. The drug release rate is significantly faster near tumor tissues with a low pH value, and the property of selectively releasing drugs near tumors is relatively strong. (10) Provide a method for producing a novel material that is poly[2-carboxyacrylic acid] rich in carboxyl groups. (11) Using poly[2-carboxyacrylic acid], a novel nano-drug carrier can be produced. (12) The novel nano-drug carrier can enhance the therapeutic effect of the carried drug on the lesion tissue. (13) The novel nano-drug carrier can reduce the toxicity and side effects of the carried drug on normal tissues.

Brief Description of the Drawings

[0030]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Mode for Carrying Out the Invention

[0031] Hereinafter, the present invention will be further described with specific examples. Unless otherwise specified, the raw materials and apparatuses used in the present invention are all commonly used raw materials and apparatuses.

Example

[0032] Example 1 Production of poly[2-cyanoacrylic acid] (1) Formulation: n-butyl α-cyanoacrylate Normal saline, sesame oil, Tween-80, Span-20, absolute ethanol n-Butyl α-cyanoacrylate was dissolved in pyrogen-free refined sesame oil to form 10 mL of a 30% n-butyl α-cyanoacrylate oil solution, which was dispersed in a 0.25% aqueous physiological saline solution of Tween-80 and Span-20 with a pH value of 4.0. Next, the pH value was adjusted to 7.8 to initiate the polymerization reaction of n-butyl α-cyanoacrylate. After 12 hours, the precipitate was centrifuged. The operation of washing the precipitate with absolute ethanol and centrifuging was repeated 5 times. The precipitate was dispersed in 50 mL of absolute ethanol, sodium hydroxide was added, and the ester bond was selectively hydrolyzed so as to leave the cyano group. Absolute ethanol was removed by evaporation under reduced pressure, and it was further mixed with 100 mL of distilled water and centrifuged at 8000 rpm for 20 minutes, and the supernatant was discarded. The operation of washing with water while shaking and centrifuging was repeated 5 times to obtain poly[2-cyanoacrylic acid].

[0033] (2) Formulation: octyl α-cyanoacrylate 50% glucose solution, poloxamer, absolute ethanol Octyl α-cyanoacrylate was dissolved in a 50% glucose solution with 0.25% poloxamer at pH 4.0 to form an octyl α-cyanoacrylate emulsion. The pH value was adjusted to 7.4 and polymerized at room temperature for 12 hours with stirring. After centrifugation, the precipitate was dispersed in 50 ml of absolute ethanol, sodium hydroxide was added, and the ester bond was selectively hydrolyzed to leave the cyano group. After removing absolute ethanol by evaporation under reduced pressure, it was mixed with 100 mL of distilled water, centrifuged at 8000 rpm for 20 minutes, and the supernatant was discarded. The operation of washing with water while shaking and centrifuging was repeated 5 times to obtain poly[2-cyanoacrylic acid].

[0034] (3) Prescription: Isobutyl α-cyanoacrylate 10% dextran solution, polyethylene glycol 400 monooleate, absolute ethanol Isobutyl α-cyanoacrylate was dissolved in a 10% dextran solution with 0.25% polyethylene glycol 400 monooleate at pH 4.0 to form an isobutyl α-cyanoacrylate emulsion. The pH value was adjusted to 7.4 and polymerized at room temperature for 12 hours with stirring. After centrifugation, the precipitate was dispersed in 50 ml of absolute ethanol, sodium hydroxide was added, and the ester bond was selectively hydrolyzed to leave the cyano group. After removing absolute ethanol by evaporation under reduced pressure, it was mixed with 100 mL of distilled water, centrifuged at 8000 rpm for 20 minutes, and the supernatant was discarded. The operation of washing with water while shaking and centrifuging was repeated 5 times to obtain poly[2-cyanoacrylic acid].

[0035] (4) Prescription: n-Butyl α-cyanoacrylate Absolute ethanol n-Butyl α-cyanoacrylate was dissolved in absolute ethanol to form a 50% ethanol solution and polymerized for one week. Next, sodium hydroxide was added to selectively hydrolyze the ester bond while leaving the cyano group. After removing absolute ethanol by evaporation under reduced pressure, it was mixed with 100 mL of distilled water, centrifuged at 8000 rpm for 20 minutes, and the supernatant was discarded. The operation of washing with water while shaking and centrifuging was repeated 5 times to obtain poly[2-cyanoacrylic acid].

[0036] (5) Formulation: Methyl α-cyanoacrylate Acetone, absolute ethanol Methyl α-cyanoacrylate was dissolved in acetone to form a 50% acetone solution and polymerized for two weeks. Next, acetone was removed under reduced pressure and dispersed in absolute ethanol. Further, sodium hydroxide was added to selectively hydrolyze the ester bond while leaving the cyano group. After removing absolute ethanol by evaporation under reduced pressure, it was mixed with 100 mL of distilled water, centrifuged at 8000 rpm for 20 minutes, and the supernatant was discarded. The operation of washing with water while shaking and centrifuging was repeated 5 times to obtain poly[2-cyanoacrylic acid].

[0037] (6) Formulation: Ethyl α-cyanoacrylate Acetonitrile, absolute ethanol Ethyl α-cyanoacrylate was dissolved in acetonitrile to form a 50% acetonitrile solution and polymerized for two weeks. Next, acetonitrile was removed under reduced pressure and dispersed in absolute ethanol. Further, sodium hydroxide was added to selectively hydrolyze the ester bond while leaving the cyano group. After removing absolute ethanol by evaporation under reduced pressure, it was mixed with 100 mL of distilled water, centrifuged at 8000 rpm for 20 minutes, and the supernatant was discarded. The operation of washing with water while shaking and centrifuging was repeated 5 times to obtain poly[2-cyanoacrylic acid].

[0038] Example 2 Preparation of Poly[2-cyanoacrylic acid] Unsupported Plug Microspheres (1) Formulation: Poly[2-cyanoacrylic acid] Absolute ethanol, water Using 0.5 g of poly[2-cyanoacrylic acid], a 5 mL anhydrous ethanol solution was prepared. It was placed in a rotary evaporator, the ethanol was volatilized to form a thin film on the wall of the rotary evaporator, mixed with 50 mL of distilled water, hydrated for 12 hours, centrifuged at 8000 rpm for 20 minutes, and the supernatant was discarded. The operation of washing with shaking and centrifuging was repeated 5 times to obtain unsupported plug microspheres.

[0039] (2) Prescription: poly[2-cyanoacrylic acid] Aminopolyethylene glycol 2000, water The carboxyl groups were modified with aminopolyethylene glycol 2000. The catalysts used in the modification with activated polyethylene glycol were EDC·HCl (1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride) and NHS (N-hydroxysuccinimide). After modification with polyethylene glycol, it was centrifuged at 8000 rpm for 20 minutes, and the supernatant was discarded. The operation of washing with shaking and centrifuging was repeated 5 times to obtain unsupported plug microspheres modified with polyethylene glycol.

[0040] Example 3 Preparation of poly[2-cyanoacrylic acid] drug-loaded plug microspheres (1) Prescription: Unsupported plug microspheres Adriamycin 1 mL of unsupported plug microspheres was mixed with the same volume of 2 mg / mL Adriamycin in 1 / 15 M isotonic phosphate buffer with a pH value of 7.4, shaken for 15 minutes, and after discarding the remaining Adriamycin solution, it was washed with 1 / 15 M isotonic phosphate buffer with a pH value of 7.4 to obtain Adriamycin-loaded plug microspheres for tumor arterial embolization.

[0041] (2) Prescription: Unsupported plug microspheres Gentamicin The non-supported embolization microspheres of 1 mL were mixed with an equal volume of 10 mg / mL gentamicin in 1 / 15 M isotonic phosphate buffer at pH 7.4, shaken for 5 minutes, and after discarding the remaining gentamicin solution, they were washed with 1 / 15 M isotonic phosphate buffer at pH 7.4 to obtain gentamicin-supported embolization microspheres for the treatment of inflammation. Effectiveness of poly[2-cyanoacrylate] embolization microspheres

[0042] 1. Novel non-supported embolization microspheres The particle size and surface morphological characteristics of the novel non-supported embolization microspheres were observed and measured using an optical microscope and a scanning electron microscope (shown in Figure 2). Under different storage temperature conditions, the change in particle size during long-term storage of the novel non-supported embolization microspheres was detected. The novel non-supported embolization microspheres can be used for the embolization treatment of arterial bleeding such as traumatic pelvic and visceral hemorrhage, urinary system hemorrhage, gastrointestinal hemorrhage, severe nasal and maxillofacial hemorrhage, massive hemoptysis, and postoperative visceral hemorrhage. They can also be used for the embolization treatment of venous bleeding such as gastrointestinal venous aneurysm-like swelling.

[0043] 2. Novel drug-supported embolization microspheres The drug loading amount, the rate of spontaneous drug loading, and the drug release rate of the novel drug-loaded embolization microspheres were measured using an ultraviolet-visible spectrophotometer. A rabbit VX2 liver cancer model was established using the tumor tissue block embedding method, and the effectiveness of adriamycin-loaded embolization microspheres in the hepatic artery was evaluated (shown in Figure 3). Two weeks after embedding and transplanting the tumor blocks, laparotomy was performed, a catheter was inserted into the hepatic artery, and adriamycin-loaded embolization microspheres were injected (shown in Figure 4). The adriamycin concentration in the peripheral venous blood of the experimental rabbits was measured by high performance liquid chromatography. The distribution of adriamycin in the tumor and the density of tumor microvessels were observed using immunofluorescence staining technology. As shown in the results, the size of this novel drug-loaded embolization microspheres can effectively embolize tumor arterial blood vessels, the anti-tumor effect is remarkable, and the density of tumor blood vessels is significantly reduced. According to animal experiments, this novel drug-loaded embolization microspheres can also be used for the treatment of renal cancer, adrenal cancer, various tumors rich in blood vessels in the pelvis, maxillofacial malignant tumors, malignant tumors of the extremities and spine pelvis. The novel drug-loaded embolization microspheres can carry any drug with a positive charge for use in vascular embolization treatment with specific requirements, enhance the therapeutic effect of the drug on the local lesion tissue, and reduce the systemic toxicity and side effects of the drug (shown in Figure 5).

[0044] Example 4 Preparation of poly[2-carboxyacrylic acid] (1) Formulation: n-butyl α-cyanoacrylate 0.9 mL Tween-80 3.0 mL Physiological saline (pH value 2.0) 50 mL Manufacturing process: Dissolve Twin-80 in physiological saline, adjust the pH value to 2.0 with 0.01N hydrochloric acid, and gradually add n-butyl α-cyanoacrylate dropwise over 9 minutes under high-speed dispersion conditions with a hard plastic rotor. Disperse it at high speed in ice water with a hard plastic tissue disperser for 45 minutes, filter it through a 0.45μm membrane filter, adjust the pH value to 7.8 with 0.01N sodium hydroxide, and let it stand overnight. Centrifuge at low temperature at 8000 rpm for 20 minutes, wash it with 50% ethanol and centrifuge at 8000 rpm for 20 minutes, repeat this operation 3 times, collect the precipitate, add 95% ethanol, hydrolyze it with 0.1N sodium hydroxide to obtain a light yellow solution. Remove the solvent with a rotary evaporator, adjust the pH value to 7.4 with 0.1N hydrochloric acid, put it into a dialysis bag with a fractional molecular weight of 10,000, perform dialysis against pure water, change the dialysis solution every 12 hours, and lyophilize it to obtain poly[2-carboxyacrylic acid].

[0045] (2) Prescription: 0.9 mL of octyl α-cyanoacrylate 6.0 mL of polyethylene glycol 400 monooleate 50 mL of 50% glucose (pH value 2.0) Manufacturing process: Add polyethylene glycol 400 monooleate to 50% glucose, adjust the pH value to 2.0 with 0.01N hydrochloric acid, and gradually add octyl α-cyanoacrylate dropwise over 9 minutes under high-speed dispersion conditions with a hard plastic rotor. Disperse it in ice water with a hard plastic tissue disperser for 5 minutes, filter it through a 0.45μm membrane filter, adjust the pH value to 7.8 with 0.01N sodium hydroxide, disperse it, and continue overnight. Centrifuge at low temperature at 8000 rpm for 40 minutes, wash it with pure water and centrifuge at 8000 rpm for 20 minutes, repeat this operation 3 times, collect the precipitate, add an appropriate amount of 95% ethanol, hydrolyze it with 0.1N sodium hydroxide to obtain a light yellow solution. Remove the solvent with a rotary evaporator, adjust the pH value to 7.4 with 0.1N hydrochloric acid, put it into a dialysis bag with a fractional molecular weight of 10,000, perform dialysis against pure water, change the dialysis solution every 12 hours, and lyophilize it to obtain poly[2-carboxyacrylic acid].

[0046] (3) Prescription: 0.9 mL of n-butyl α-cyanoacrylate 2.1 mL of refined soybean oil 6.0 mL of Tween-80 1.2 mL of Span-20 50 mL of 20% glucose (pH value 2.0) Manufacturing process: Tween-80 and Span-20 were added to 20% glucose, and the pH value was adjusted to 2.0 with 0.01 N hydrochloric acid. n-butyl α-cyanoacrylate was added to soybean oil to prepare a solution with good fluidity. Under the condition of high-speed dispersion with a hard plastic rotor, the soybean oil solution of n-butyl α-cyanoacrylate was gradually dropped over 9 minutes. It was dispersed in ice water with a hard plastic tissue disperser for 5 minutes, filtered through a 0.45 μm membrane filter, the pH value was adjusted to 12 with 0.01 N sodium hydroxide, and the dispersion was continued overnight. It was centrifuged at 8000 rpm for 40 minutes at low temperature, washed with pure water, and the centrifugation operation at 8000 rpm for 20 minutes was repeated 3 times. The precipitate was collected, an appropriate amount of 95% ethanol was added, and it was hydrolyzed with 0.1 N sodium hydroxide to obtain a pale yellow solution. The solvent was removed with a rotary evaporator, the pH value was adjusted to 7.4 with 0.1 N hydrochloric acid, put into a dialysis bag with a fractional molecular weight of 10,000, dialyzed against pure water, the dialysis solution was changed every 12 hours, and freeze-dried to obtain poly[2-carboxyacrylic acid].

[0047] (4) Prescription: 0.9 mL of isobutyl α-cyanoacrylate 6.0 mL of poloxamer 50 mL of 5% dextran (pH value 2.0) Manufacturing process: Add poloxamer to 5% dextran, adjust the pH value to 2.0 with 0.01N hydrochloric acid, and gradually add isobutyl α-cyanoacrylate dropwise over 9 minutes under high-speed dispersion conditions with a hard plastic rotor. Disperse in ice water with a hard plastic tissue disperser for 5 minutes, filter through a 0.45μm membrane filter, adjust the pH value to 7.8 with 0.01N sodium hydroxide, disperse, and continue overnight. Centrifuge at 8000 rpm for 40 minutes at low temperature, wash with pure water and centrifuge at 8000 rpm for 20 minutes, repeat this operation 3 times, collect the precipitate, add an appropriate amount of 95% ethanol, hydrolyze with 0.1N sodium hydroxide to obtain a light yellow solution. Remove the solvent with a rotary evaporator, adjust the pH value to 7.4 with 0.1N hydrochloric acid, put it into a dialysis bag with a fractional molecular weight of 10,000, perform dialysis against pure water, change the dialysis solution every 12 hours, and lyophilize to obtain poly[2-carboxyacrylic acid].

[0048] (5) Prescription: n-butyl α-cyanoacrylate 0.9 mL Absolute ethanol 5.0 mL Water (pH value 2.0) 50 mL Manufacturing process: Add n-butyl α-cyanoacrylate to absolute ethanol to obtain a transparent solution, and gradually add the absolute ethanol solution of n-butyl α-cyanoacrylate dropwise over 9 minutes under high-speed dispersion conditions with a hard plastic rotor. Disperse in ice water with a hard plastic tissue disperser for 15 minutes, filter through a 0.45μm membrane filter, adjust the pH value to 7.8 with 0.01N sodium hydroxide, disperse, and continue overnight. Centrifuge at 8000 rpm for 15 minutes at low temperature, wash with pure water and centrifuge at 8000 rpm for 15 minutes, repeat this operation 3 times, collect the precipitate, add an appropriate amount of 95% ethanol, hydrolyze with 0.1N sodium hydroxide to obtain a light yellow solution. Remove the solvent with a rotary evaporator, adjust the pH value to 7.4 with 0.1N hydrochloric acid, put it into a dialysis bag with a fractional molecular weight of 10,000, perform dialysis against pure water, change the dialysis solution every 12 hours, and lyophilize to obtain poly[2-carboxyacrylic acid].

[0049] (6) Prescription: 0.9 mL of methyl α-cyanoacrylate 5.0 mL of acetone 50 mL of water (pH value 2.0) Manufacturing process: Methyl α-cyanoacrylate was added to acetone to obtain a clear solution. Under the condition of high-speed dispersion with a hard plastic rotor, the acetone solution of methyl α-cyanoacrylate was gradually dropped over 9 minutes. It was dispersed in ice water with a hard plastic tissue disperser for 15 minutes, filtered through a 0.45 μm membrane filter, the pH value was adjusted to 7.8 with 0.01 N sodium hydroxide, and dispersion was continued overnight. It was centrifuged at 8000 rpm for 15 minutes at low temperature, washed with pure water and centrifuged at 8000 rpm for 15 minutes, and this operation was repeated 3 times. The precipitate was collected, an appropriate amount of 95% ethanol was added, and it was hydrolyzed with 0.1 N sodium hydroxide to obtain a pale yellow solution. The solvent was removed with a rotary evaporator, the pH value was adjusted to 7.4 with 0.1 N hydrochloric acid, put into a dialysis bag with a molecular weight cut-off of 10,000, dialysis was carried out against pure water, the dialysis solution was changed every 12 hours, and it was freeze-dried to obtain poly[2-carboxyacrylic acid].

[0050] (7) Prescription: 0.9 mL of ethyl α-cyanoacrylate 5.0 mL of acetonitrile 50 mL of water (pH value 2.0) Manufacturing process: Ethyl α-cyanoacrylate was added to acetonitrile to obtain a transparent solution. Under the condition of high-speed dispersion with a hard plastic rotor, the acetonitrile solution of ethyl α-cyanoacrylate was gradually dropped over 9 minutes. It was dispersed in ice water with a hard plastic tissue disperser for 15 minutes, filtered through a 0.45 μm membrane filter, the pH value was adjusted to 7.8 with 0.01 N sodium hydroxide, and the dispersion was continued overnight. It was centrifuged at low temperature at 8000 rpm for 15 minutes, washed with pure water and centrifuged at 8000 rpm for 15 minutes, and this operation was repeated 3 times. The precipitate was collected, an appropriate amount of 95% ethanol was added, and it was hydrolyzed with 0.1 N sodium hydroxide to obtain a pale yellow solution. The solvent was removed with a rotary evaporator, the pH value was adjusted to 7.4 with 0.1 N hydrochloric acid, put into a dialysis bag with a molecular weight cut-off of 10000, dialyzed against pure water, the dialysis solution was changed every 12 hours, and freeze-dried to obtain poly[2-carboxyacrylic acid].

[0051] Example 5 Preparation of Poly[2-carboxyacrylic acid] Nanodrug Carrier (1) Formulation: 590 mg of poly[2-carboxyacrylic acid] 2000 mg of aminopolyethylene glycol 2000 Manufacturing process: Under the condition of magnetic stirring, using 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride [1-Ethyl-3-(3-dimethylaminopropyl)carbodiimide, EDC·HCL] and N-hydroxysuccinimide (N-Hydroxy succinimide, NHS) as catalysts, 2 g of NH 2 -PEG was added to the nanodrug carrier backbone solution, and the reaction to modify the nanodrug carrier backbone was carried out overnight. The said solution was put into a dialysis bag and dialyzed against distilled water for 72 hours, and the water was changed every 12 hours to remove impurities with a molecular weight less than 10000, and a nanodrug carrier with the surface covered by PEG2000 was obtained. The pH value was adjusted to 7.4 to obtain the nanodrug carrier.

[0052] (2) Formulation: 590 mg of poly[2-carboxyacrylic acid] 2000 mg of polyethylene glycol-hydrazide Manufacturing process: Under the condition of magnetic stirring, using 1-Ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride [EDC·HCl] and 1-Hydroxybenzotriazole (HOBT) as catalysts, 2 g of NH 2 -PEG was added to the nano-drug carrier skeleton solution, and the reaction to modify the nano-drug carrier skeleton was carried out overnight. The above solution was put into a dialysis bag and dialyzed against distilled water for 72 hours, with water being changed every 12 hours to remove impurities with a molecular weight of less than 10,000, and a nano-drug carrier with a surface covered by PEG2000 was obtained. The pH value was adjusted to 7.4 to obtain the nano-drug carrier.

[0053] (3) Prescription: Hydrogenated lecithin 60 mmol Cholesterol 40 mmol PEG2000-DSPE 10 mmol Poly[2-carboxyacrylic acid] 0.5% Manufacturing process: The above materials were dissolved in 50 mL of absolute ethanol, and the absolute ethanol was removed by a rotary evaporator to obtain a liposome membrane. After adding 50 mL of water for hydration, it was filtered through a 200 nm membrane filter, and the pH value was adjusted to 7.4 with 0.001 N sodium hydroxide. Poly[2-carboxyacrylic acid] not encapsulated in the liposome was removed by gel permeation chromatography, and after filtration, a nano-drug carrier, which is a nanoliposome capable of spontaneously carrying positively charged drugs, was obtained. Effectiveness of the poly[2-carboxyacrylic acid] nano-drug carrier

[0054] The novel nano-drug carrier had a spherical morphology, uniform particle size and uniform distribution under a scanning electron microscope, and its Zeta potential reached -52.5 mV. Taking adriamycin as an example, in mouse S180 sarcoma animal models and C57BL6 tumor lung metastasis animal models, this nano-formulated adriamycin was demonstrated to enhance the anti-tumor effect (P<0.01), significantly reduce the toxicity of adriamycin to the heart, and particularly significantly reduce the incidence of heart failure caused by adriamycin. When evaluating the drug efficacy using a rabbit liver cancer model, the nano-formulated adriamycin showed a significantly enhanced anti-cancer effect (P<0.01) compared to adriamycin. After carrying adriamycin, the novel nano-drug carrier becomes nano-formulated adriamycin with its surface covered by polyethylene glycol. After entering the body, it can circulate in the blood for a long time. It is difficult to enter normal tissues with extremely low vascular permeability, but it can passively accumulate in tumor tissues with high vascular permeability, thus enhancing the anti-tumor effect of adriamycin and reducing the toxicity of adriamycin. By adding this product to freeze-dried adriamycin and shaking, nano-formulated adriamycin drugs can be formed. It can also carry other drugs with a positive charge. After entering the blood by intravenous drip, the novel nano-drug carrier accumulates in tumor tissues, infection sites or inflammation sites with high vascular permeability, thus enhancing the efficacy of anti-cancer agents, antibacterial agents or anti-tumor agents and reducing their side effects. According to the results of the in vivo distribution study, the novel nano-lipid drug carrier significantly reduces the distribution to normal tissue organs such as the heart of adriamycin and significantly increases the distribution to tumors or infectious / inflammatory lesions. The results are shown in Figures 6 to 8.

[0055] The above-described embodiments are merely illustrative and explanatory of the present invention, and are not intended to limit the present invention to the scope of these embodiments. Also, those skilled in the art should understand that the present invention is not limited to the above embodiments, and various changes and modifications can be made based on the teachings of the present invention, and all of these changes and modifications are included in the protection scope of the present invention.

Claims

1. A method for producing poly[2-cyanoacrylic acid] consisting of repeating units represented by the following chemical formula, 【Chemical 1】 a step of preparing an emulsion of 2-cyanoacrylate or its vegetable oil solution using a nonionic surfactant in physiological saline with a pH value of 2.0 to 4.0, a glucose solution of 5% or more, or a dextran solution of 5% or more; a step of adjusting the pH value of the emulsion to 7.4 or more to accelerate the polymerization reaction to form poly[2-cyanoacrylate]; a step of selectively hydrolyzing the ester bond of the poly[2-cyanoacrylate] under alkaline conditions so as to leave the cyano group; a step of removing impurities by dialysis to obtain poly[2-cyanoacrylic acid], characterized in that the method for producing poly[2-cyanoacrylic acid] has these steps.

2. A method for producing poly[2-cyanoacrylic acid] consisting of repeating units represented by the following chemical formula, 【Chemical Formula 2】 a step of dissolving 2-cyanoacrylate in absolute ethanol, acetone or acetonitrile; a step of gradually dropping the absolute ethanol, acetone or acetonitrile solution of 2-cyanoacrylate into acidic water under the condition of high-speed dispersion with a hard plastic disperser and stirring magnetically overnight; a step of collecting the precipitate of poly[2-cyanoacrylate] by high-speed centrifugation; a step of selectively hydrolyzing the ester bond of the poly[2-cyanoacrylate] under alkaline conditions so as to leave the cyano group; a step of removing impurities by dialysis to obtain poly[2-cyanoacrylic acid], characterized in that the method for producing poly[2-cyanoacrylic acid] has these steps.

3. In the hydrolysis step, the method for producing poly[2-cyanoacrylic acid] according to Claim 1 or 2, characterized in that sodium hydroxide is added to a dispersion in which the poly[2-cyanoacrylate] is dispersed in absolute ethanol, and the ester bond in the poly[2-cyanoacrylate] is selectively hydrolyzed under alkaline conditions.

4. A method for producing poly[2-cyanoacrylic acid] consisting of repeating units represented by the following chemical formula, [Chemical Formula 3] A method for producing poly[2-cyanoacrylic acid], which comprises first producing poly[2-cyanoacrylate], then adding sodium hydroxide to a dispersion obtained by dispersing the resulting poly[2-cyanoacrylate] in absolute ethanol, selectively hydrolyzing the ester bond in poly[2-cyanoacrylate] under alkaline conditions, and further purifying to obtain poly[2-cyanoacrylic acid].

5. An unsupported embolization microsphere, wherein the unsupported embolization microsphere has a particle diameter of 1 μm or more and is produced using a hydrolysis product of poly[2-cyanoacrylate], and the hydrolysis product of poly[2-cyanoacrylate] is poly[2-cyanoacrylic acid] composed of repeating units represented by the following chemical formula. An unsupported embolization microsphere characterized by that. [Chemical Formula 4]

6. The unsupported embolization microsphere according to claim 5, characterized in that the unsupported embolization microsphere is obtained by dispersing poly[2-cyanoacrylic acid] in water to form a negatively charged microsphere.

7. The unsupported embolization microsphere according to claim 5 or 6, characterized in that the unsupported embolization microsphere is for vascular embolization.

8. The unsupported embolization microsphere according to any one of claims 5 to 7, characterized in that the unsupported embolization microsphere is deformable.

9. A drug-loaded embolization microsphere characterized by being produced using the unsupported embolization microsphere according to any one of claims 5 to 8.

10. The drug-loaded embolization microsphere according to claim 9, characterized in that the drug-loaded embolization microsphere is obtained by binding an unsupported embolization microsphere and a drug having a positive charge by ionic bond.

11. The drug-loaded embolization microsphere according to claim 9 or 10, characterized in that the drug-loaded embolization microsphere spontaneously carries and releases a drug based on the principle of charge reversal.

12. The drug-loaded embolization microsphere according to any one of claims 9 to 11, characterized in that the drug-loaded embolization microsphere releases a drug directly to the local lesion tissue in a lesion tissue having a pH value of 6.5 or less.

13. A method for producing poly[2-carboxyacrylic acid] composed of repeating units represented by the following chemical formula, wherein 【Chemical Formula 6】 First, poly[2-cyanoacrylate] is produced, and then the obtained poly[2-cyanoacrylate] is collected. 95% ethanol and 0.1 N sodium hydroxide solution are added, and the ester bond and cyano group of poly[2-cyanoacrylate] are hydrolyzed under alkaline conditions. Further, impurities are removed by dialysis to obtain poly[2-carboxyacrylic acid]. A method for producing poly[2-carboxyacrylic acid], characterized in that.

14. The method for producing poly[2-carboxyacrylic acid] according to claim 13, wherein the dialysis is dialysis using a dialysis bag with a molecular weight cut-off of 10,000.

15. A nanodrug carrier obtained using the hydrolysis product of poly[2-cyanoacrylate], The hydrolysis product of the poly[2-cyanoacrylate] is poly[2-carboxyacrylic acid] consisting of repeating units represented by the following chemical formula. A nanodrug carrier characterized by that. [Chemical Formula 7]

16. The nanodrug carrier according to claim 15, wherein the hydrolysis product of the poly[2-cyanoacrylate] is dialyzed using a dialysis bag with a molecular weight cut-off of 10,000.

17. The nanodrug carrier is obtained by modifying a part of the carboxy groups of poly[2-carboxyacrylic acid] with activated polyethylene glycol. The nanodrug carrier according to claim 15 or 16, characterized by that.

18. The nanodrug carrier is obtained by encapsulating poly[2-carboxyacrylic acid] in liposomes. The nanodrug carrier according to claim 15 or 16, characterized by that.

19. The nanodrug carrier spontaneously carries and releases drugs based on the principle of charge reversal. The nanodrug carrier according to any one of claims 15 to 18, characterized by that.

20. The drug is a drug having a positive charge. The nanodrug carrier according to claim 19, characterized by that.

21. The nanodrug carrier targets and delivers drugs through the blood, accumulates in diseased tissues with a pH value of 6.5 or less, and directly releases drugs to the diseased tissues. The nanodrug carrier according to any one of claims 15 to 20, characterized by that.

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