CN117462729A

CN117462729A - Polycyanoacrylic acid-cyanoacrylate embolism microsphere, preparation method and application thereof

Info

Publication number: CN117462729A
Application number: CN202311588835.9A
Authority: CN
Inventors: 徐景海; 沈伟; 沈萧; 田明月
Original assignee: BEIJING COMPONT MEDICAL DEVICES CO LTD
Current assignee: BEIJING COMPONT MEDICAL DEVICES CO LTD
Priority date: 2023-11-24
Filing date: 2023-11-24
Publication date: 2024-01-30

Abstract

The invention relates to the technical field of medical instruments, and discloses polycyanoacrylic acid-cyanoacrylate embolic microspheres, and a preparation method and application thereof. The method comprises the following steps: (1) In the presence of an initiator, a mixed solution of cyanoacrylate compounds, a dispersing agent and water is subjected to polymerization reaction to obtain polycyanoacrylate microspheres; (2) Adding the polycyanoacrylate microspheres obtained in the step (1) into alkali liquor to perform partial hydrolysis reaction to obtain polycyanoacrylic acid-cyanoacrylate embolic microspheres. The polycyanoacrylic acid-cyanoacrylate embolic microsphere can be used for preparing vascular embolism therapeutic drugs. The microsphere prepared by the invention has the advantages of convenient preparation, uniform particle size, good elasticity, large drug loading capacity and the like, can be used for preparing vascular embolism treatment drugs, and has good application prospect.

Description

Polycyanoacrylic acid-cyanoacrylate embolism microsphere, preparation method and application thereof

Technical Field

The invention relates to the technical field of medical instruments, in particular to a polycyanoacrylic acid-cyanoacrylate embolic microsphere, a preparation method and application thereof.

Background

In recent years, embolic therapy has become an important interventional therapy. The principle is that by means of high-definition medical imaging equipment, the artificial embolic material loaded with anti-tumor medicine is injected into blood vessel through precise instruments such as catheter, guide wire, etc., so that the blood vessel is blocked, and blood supply to tumor part is blocked, and the anti-tumor medicine is released, so that tumor atrophy and necrosis are caused. The embolism therapy has better curative effect on arteriovenous malformations, vascular enlargement type tumors, uterine fibroids, blood supply abundant type tumors and the like by blocking blood vessels supplying blood to tumors, malformed blood vessels or bleeding blood vessels.

The interventional embolism (TACE) is to inject embolic material into the target blood vessel via the catheter, and has the advantages of small trauma, high accuracy, strong operation controllability, quick effect, less complications and the like. The composition is widely applied to the treatment of vascular lesions, rich blood supply tumors, organ hyperfunction and the like clinically, and is one of important basic technologies of interventional radiology. The most widely used clinical application is microsphere embolic agent at present. Early embolic microspheres are mainly sodium alginate microspheres, polyvinyl alcohol microspheres and the like, and have the defects of uneven particle size, poor dispersibility, poor elasticity and the like, so that drifting, false embolism, ectopic embolism and the like occur in interventional operation, and normal tissues are damaged.

At present, the main stream products sold in the domestic market are polyvinyl alcohol embolism microspheres, and the phenomenon of blocking microcatheters is easy to occur in clinical application, so that the use of the microspheres is influenced. And the drug carrying performance needs to functionalize some anionic groups such as carboxyl, sulfonic group and the like, so that the drug carrying capability is weak, and the application of the drug carrying capability is limited.

Disclosure of Invention

The invention aims to solve the problems of nonuniform particle size, poor dispersibility, poor elasticity and poor drug carrying capacity of embolic microspheres in the prior art, and provides polycyanoacrylic acid-cyanoacrylate embolic microspheres, and a preparation method and application thereof.

In order to achieve the above object, a first aspect of the present invention provides a method for preparing polycyanoacrylic acid-cyanoacrylate embolic microspheres, the method comprising the steps of:

(1) In the presence of an initiator, a mixed solution of cyanoacrylate compounds, a dispersing agent and water is subjected to polymerization reaction to obtain polycyanoacrylate microspheres;

(2) Adding the polycyanoacrylate microspheres obtained in the step (1) into alkali liquor to perform partial hydrolysis reaction to obtain polycyanoacrylic acid-cyanoacrylate embolic microspheres.

In a second aspect, the invention provides polycyanoacrylic acid-cyanoacrylate embolic microspheres prepared by the preparation method described in the first aspect.

In a third aspect, the invention provides the use of the polycyanoacrylic acid-cyanoacrylate embolic microsphere according to the second aspect in the preparation of a vascular embolism therapeutic drug.

Through the technical scheme, the beneficial technical effects obtained by the invention are as follows:

the preparation method of the polycyanoacrylic acid-cyanoacrylate embolism microsphere provided by the invention uses water as a medium, and adds a composite dispersing agent, and then the cyanoacrylate compound is dropwise added under high-speed stirring, and under the initiation of an initiator, the generated polymer microsphere is subjected to acid treatment, centrifugation or filtration, and after washing with purified water, saponification reaction (partial hydrolysis reaction) is carried out, so that the partially hydrolyzed cyanoacrylate microsphere is obtained. The microsphere has the advantages of convenient preparation, uniform particle size, good elasticity, large drug-loading capacity and the like, can be used for preparing vascular embolism treatment drugs, and has good application prospect.

Detailed Description

The endpoints and any values of the ranges disclosed herein are not limited to the precise range or value, and are understood to encompass values approaching those ranges or values. For numerical ranges, one or more new numerical ranges may be found between the endpoints of each range, between the endpoint of each range and the individual point value, and between the individual point value, in combination with each other, and are to be considered as specifically disclosed herein.

The first aspect of the invention provides a method for preparing polycyanoacrylic acid-cyanoacrylate embolic microspheres, comprising the steps of:

According to the invention, the prepared polycyanoacrylate microsphere is subjected to partial hydrolysis to obtain the partially hydrolyzed cyanoacrylate embolic microsphere, and the unhydrolyzed ester moiety can not only provide a supporting effect on the microsphere, but also play a role in internal plasticization, so that the prepared microsphere has good elasticity.

In some embodiments of the invention, the initiator is selected from at least one of piperazine, lysine, cystine, cysteine, arginine, homoarginine, polyethylenimine, and polylysine.

In the invention, the selected initiator has a plurality of active centers in each molecule, and the active centers can initiate cyanoacrylate compounds to generate polymerization reaction, thereby playing the role of crosslinking cyanoacrylate polymers and further improving the elasticity of the generated bodily polymers.

In some embodiments of the invention, the mass ratio of initiator to cyanoacrylate is from 0.0001 to 0.1:1, preferably from 0.015 to 0.025:1.

In some embodiments of the present invention, the cyanoacrylate compound is selected from at least one of n-butyl cyanoacrylate, isobutyl cyanoacrylate, n-hexyl cyanoacrylate, n-octyl cyanoacrylate, isooctyl cyanoacrylate, sec-octyl cyanoacrylate, methoxyethyl cyanoacrylate, and ethoxyethyl cyanoacrylate.

The cyanoacrylate compounds used in the invention are selected from the compounds with longer chains. Methyl cyanoacrylate and ethyl cyanoacrylate cannot be used for the preparation of microspheres due to their own toxicity. The toxicity of the cyanoacrylate compound with longer chain length can meet the requirement. In addition, the chain length is longer, the internal plasticization effect can be achieved, and the prepared microsphere is good in elasticity.

In some embodiments of the invention, the mass ratio of water to cyanoacrylate is from 0.2 to 20:1, preferably 10:1.

In some embodiments of the invention, the dispersant is a composite dispersant comprising a primary dispersant and a secondary dispersant; the main dispersant is at least one selected from polyacrylic acid, acrylic acid-acrylic acid ester copolymer, maleic acid-acrylic acid copolymer, ethylene-acrylic acid copolymer, styrene-acrylic acid copolymer, polymethacrylic acid, methacrylic acid-methacrylic acid ester copolymer, ethylene-methacrylic acid copolymer and styrene-methacrylic acid copolymer; the auxiliary dispersing agent is at least one selected from polyethylene glycol and derivatives thereof, ethylene glycol-propylene glycol copolymer (such as poloxamer 188) and derivatives thereof (such as Plurafac LF 901), cellulose derivatives, polydextrose and polyvinyl alcohol.

In the invention, the main dispersant in the selected composite dispersant is a polycarboxylic acid substance and a weak acid substance, can inhibit the cyanoacrylate from undergoing a polymerization reaction in water, has a similar structure to the cyanoacrylate, and has certain solubility. And a large amount of acid anions are ionized in the water phase, so that the stability of liquid drops can be effectively maintained, and when cyanoacrylate undergoes polymerization, grafting reaction does not occur, phase inversion is caused, and the stability of a suspension system can be effectively maintained. The auxiliary dispersing agent is a nonionic surfactant, so that the surface tension of the system can be reduced, and the particle size of formed liquid drops can be controlled by adjusting the dosage of the auxiliary dispersing agent.

In some embodiments of the invention, the mass ratio of primary dispersant, secondary dispersant and water is from 0.01 to 20:0.01 to 20:100.

In some embodiments of the invention, the polymerization conditions of step (1) include: the temperature is 40-100deg.C, preferably 50-60deg.C; the time is 2-16 hours, preferably 3-6 hours.

In some embodiments of the invention, the polycyanoacrylate microspheres are obtained by adding an acid solution after the polymerization reaction in step (1). The purpose is to remove excess initiator.

In some embodiments of the present invention, after the partial hydrolysis reaction in step (2), cooling to room temperature, adding an acid solution, and adjusting the pH to 4-6.5 to obtain polycyanoacrylic acid-cyanoacrylate embolic microspheres. The purpose is that the microspheres are expected to exist in the form of acid, the product of saponification reaction is corresponding alkali metal salt, and the corresponding acid is ensured to be generated after the acid is added.

In some embodiments of the invention, the acid solution is selected from at least one of citric acid, malic acid, hydrochloric acid, sulfuric acid, methanesulfonic acid, phosphoric acid, and oxalic acid.

In some embodiments of the invention, the acid solution is present in a concentration of 5 to 20wt%.

In some embodiments of the invention, the alkaline substance in the alkaline solution is selected from at least one of sodium ethoxide, sodium hydroxide, potassium carbonate and lithium hydroxide.

In some embodiments of the invention, the molar ratio of the basic substance to the polycyanoacrylate microspheres is 0.10 to 1:1, preferably 0.60 to 1:1, based on polymerized units in the polycyanoacrylate microspheres.

In some embodiments of the invention, the conditions of the partial hydrolysis reaction of step (2) include: the temperature is 40-80 ℃, preferably 60 ℃; the time is 2-5h, preferably 3h.

According to a particularly preferred embodiment of the present invention, a process for the preparation of polycyanoacrylic acid-cyanoacrylate embolic microspheres, said process comprising the steps of:

(1) Uniformly mixing a dispersing agent and water, dropwise adding a cyanoacrylate compound into the mixture, heating to 40-100 ℃, dropwise adding an initiator solution into the mixture, reacting for 2-16 hours, adding an acid solution into the mixture, filtering, flushing, centrifuging and drying to obtain a polycyanoacrylate microsphere;

the initiator is at least one selected from piperazine, lysine, cystine, cysteine, arginine, homoarginine, polyethyleneimine and polylysine;

the dispersing agent is a composite dispersing agent and comprises a main dispersing agent and an auxiliary dispersing agent; the main dispersant is at least one selected from polyacrylic acid, acrylic acid-acrylic acid ester copolymer, maleic acid-acrylic acid copolymer, ethylene-acrylic acid copolymer, styrene-acrylic acid copolymer, polymethacrylic acid, methacrylic acid-methacrylic acid ester copolymer, ethylene-methacrylic acid copolymer and styrene-methacrylic acid copolymer; the auxiliary dispersing agent is at least one selected from polyethylene glycol and derivatives thereof, ethylene glycol-propylene glycol copolymer and derivatives thereof, cellulose derivatives, polydextrose and polyvinyl alcohol;

(2) Adding the polycyanoacrylate microspheres obtained in the step (1) into alkali liquor, carrying out partial hydrolysis reaction for 2-5h at 40-80 ℃, cooling to room temperature, adding acid liquor, adjusting the pH value to 4-6.5, filtering, repeatedly washing the solid with purified water and ethanol, and drying at 30-50 ℃ to obtain polycyanoacrylic acid-cyanoacrylate embolism microspheres.

In some embodiments of the invention, the embolic microspheres have an average particle size of 50-1000 μm.

In some embodiments of the invention, the embolic microspheres have a polydispersity of 0.035 to 0.042.

The present invention will be described in detail by examples.

The following examples and comparative examples were conducted under conventional conditions or conditions recommended by the manufacturer, where specific conditions were not noted. The reagents or apparatus used were conventional products available commercially without the manufacturer's knowledge.

In the following examples, all raw materials used are common commercially available raw materials, see table 1:

TABLE 1 part list of raw materials

Example 1:

1) Purified water (200 g) was added to a four-necked flask, and polyacrylic acid (M) was added with stirring _n =3000, 0.2 g) and poloxamer 188 (0.4 g), dropwise adding n-butyl cyanoacrylate (20 g) under high-speed stirring, heating to 50 ℃, dropwise adding an L-lysine (0.5 g) solution, then continuously reacting for 4 hours at the temperature, dropwise adding 50g of a citric acid (5%) aqueous solution, stirring for 30min, cooling, filtering, washing the microspheres with purified water (50 ml×3), and drying at 50 ℃ to obtain white microspheres (18.8 g) for later use;

2) Sodium hydroxide (2.0 g,50 mmol), ethanol (5 g) and purified water (5 g) were added to a three-necked flask, white microspheres (10 g,65 mmol) were added under stirring, heated to 60℃and subjected to partial hydrolysis for 3 hours, methanesulfonic acid (5%) solution was added, pH was adjusted to 6.0, and the mixture was filtered, and after washing the microspheres with purified water, ethanol and n-hexane in this order, the microspheres were dried to give embolic microspheres (6.8 g).

Example 2:

1) Purified water (200 g) was added to a four-necked flask, and polyacrylic acid (M) was added with stirring _n =3000, 0.5 g) and hydroxypropylmethyl cellulose (0.2 g), n-butyl cyanoacrylate (20 g) was added dropwise with high-speed stirring, heated to 60 ℃, and polyethylenimine (M _n The preparation method comprises the steps of (1) continuously reacting for 3 hours at the temperature of 600,0.5g of solution, dropwise adding 50g of aqueous solution of citric acid (5%), stirring for 30 minutes, cooling, filtering, washing microspheres with purified water (50 ml x 3), and drying at 50 ℃ to obtain white microspheres (17.8 g) for later use;

2) To a three-necked flask, potassium hydroxide (3.2 g,41 mmol), ethanol (5 g) and purified water (5 g) were added, and white microspheres (10 g,65 mmol) were added under stirring, heated to 60℃and reacted for 3 hours, methanesulfonic acid (5%) solution was added, pH was adjusted to 6.2, and the mixture was filtered, and after washing the microspheres with purified water, ethanol and n-hexane in this order, the microspheres were dried to give embolic microspheres (7.2 g).

Example 3:

1) Purified water (200 g) was added to a four-necked flask, and polymethacrylic acid (M _n =8000, 0.2 g) and polydex (0.3 g), dropwise adding n-butyl cyanoacrylate (20 g) under high-speed stirring, heating to 50 ℃, dropwise adding piperazine (0.5 g) solution, then continuously reacting for 6h at the temperature, dropwise adding 50g of citric acid (5%) aqueous solution, stirring for 30min, cooling, filtering, washing the microsphere with purified water (50 ml×3), drying at 50 ℃ to obtain white microsphere (19.2 g) for later use;

2) Sodium hydroxide (1.5 g,37.5 mmol), ethanol (5 g) and purified water (5 g) were added to a three-necked flask, white microspheres (10 g,65 mmol) were added under stirring, heated to 60℃and reacted for 3 hours, methanesulfonic acid (5%) solution was added to adjust the pH to 6.1, and after filtration, the microspheres were washed with purified water, ethanol and n-hexane in this order, and dried to give embolic microspheres (7.4 g).

Example 4:

1) Adding purified water (200 g) into a four-mouth bottle, adding polyacrylic acid (0.4 g), polydextrose (0.2 g) and Pluraac LF901 (0.3 g) under stirring, dropwise adding n-butyl cyanoacrylate (20 g) under high-speed stirring, heating to 50 ℃, dropwise adding an L-lysine (0.3 g) solution, then continuously reacting for 6h under the temperature, dropwise adding 50g of citric acid (5%) aqueous solution, stirring for 30min, cooling, filtering, washing the microspheres with purified water (50 mL of 3), and drying at 50 ℃ to obtain white microspheres (18.6 g) for later use;

2) Sodium hydroxide (1.2 g,30 mmol), ethanol (5 g) and purified water (5 g) were added to a three-necked flask, white microspheres (10 g,65 mmol) were added under stirring, heated to 60℃and reacted for 3 hours, methanesulfonic acid (5%) solution was added, pH was adjusted to 6.0, and the mixture was filtered, and after washing the microspheres with purified water, ethanol and n-hexane in this order, embolic microspheres (6.9 g) were obtained after drying.

Comparative example 1

Prepared as in example 1 except that in step (2) the polycyanoacrylate microspheres obtained in step (1) were added sodium hydroxide (5.2 g,130 mmol) to ensure complete hydrolysis of the ester groups.

Test case

The embolic microspheres prepared in examples 1-4 were tested for average particle size, polydispersity, elasticity, and doxorubicin (doxorubicin) loading, as follows:

average particle size, polydispersity: the average particle size (Dn) and polydispersity index (PDI) were calculated by counting the particle size of 100 microspheres in each sem picture using Nano measure.

Elasticity: the microsphere sample is extruded by external acting force to deform, when the sample is compressed to 50%, the pressure is removed, the microsphere starts to gradually recover the shape, when the microsphere can be recovered to be spherical or not, the structure is kept complete and is not broken, and the sample is judged to have good elasticity, otherwise, the microsphere is poor.

Doxorubicin (doxorubicin) drug loading: the detection is carried out according to the method of Chinese pharmacopoeia.

The results are shown in Table 2.

TABLE 2

As can be seen from the results of Table 2, the embolic microspheres prepared in examples 1-4 have a particle size ranging from 50-1000 μm and a polydispersity of 0.035-0.042, and the size of the embolic microspheres is very uniform; the elasticity is good; the drug loading rate of the doxorubicin is larger than 20mg/g microsphere, and the drug loading rate is large.

The invention provides a preparation method of embolic microspheres, and the prepared microspheres have the advantages of uniform particle size, good elasticity and large drug loading capacity, and can meet the clinical use requirements.

The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited thereto. Within the scope of the technical idea of the invention, a number of simple variants of the technical solution of the invention are possible, including combinations of the individual technical features in any other suitable way, which simple variants and combinations should likewise be regarded as being disclosed by the invention, all falling within the scope of protection of the invention.

Claims

1. A method for preparing polycyanoacrylic acid-cyanoacrylate embolic microspheres, comprising the steps of:

2. The method of claim 1, wherein the initiator is selected from at least one of piperazine, lysine, cystine, cysteine, arginine, homoarginine, polyethylenimine, and polylysine;

preferably, the mass ratio of the initiator to the cyanoacrylate compound is 0.0001-0.1:1, preferably 0.015-0.025:1.

3. The method according to claim 1 or 2, wherein the cyanoacrylate compound is selected from at least one of n-butyl cyanoacrylate, isobutyl cyanoacrylate, n-hexyl cyanoacrylate, n-octyl cyanoacrylate, isooctyl cyanoacrylate, sec-octyl cyanoacrylate, methoxyethyl cyanoacrylate, and ethoxyethyl cyanoacrylate;

preferably, the mass ratio of water to cyanoacrylate compound is 0.2-20:1, preferably 10:1.

4. A method according to any one of claims 1 to 3, wherein the dispersant is a complex dispersant comprising a primary dispersant and a secondary dispersant; the main dispersant is at least one selected from polyacrylic acid, acrylic acid-acrylic acid ester copolymer, maleic acid-acrylic acid copolymer, ethylene-acrylic acid copolymer, styrene-acrylic acid copolymer, polymethacrylic acid, methacrylic acid-methacrylic acid ester copolymer, ethylene-methacrylic acid copolymer and styrene-methacrylic acid copolymer; the auxiliary dispersing agent is at least one selected from polyethylene glycol and derivatives thereof, ethylene glycol-propylene glycol copolymer and derivatives thereof, cellulose derivatives, polydextrose and polyvinyl alcohol;

preferably, the mass ratio of the main dispersant to the auxiliary dispersant to the water is 0.01-20:0.01-20:100.

5. The method of any one of claims 1-4, wherein the polymerization conditions of step (1) comprise: the temperature is 40-100deg.C, preferably 50-60deg.C; the time is 2-16 hours, preferably 3-6 hours.

6. The method of any one of claims 1-5, wherein the adding acid after the polymerization in step (1) yields polycyanoacrylate microspheres;

preferably, after the partial hydrolysis reaction in the step (2), cooling to room temperature, adding acid liquor, and adjusting the pH value to 4-6.5 to obtain polycyanoacrylic acid-cyanoacrylate embolic microspheres;

preferably, the acid solution is at least one selected from the group consisting of citric acid, malic acid, hydrochloric acid, sulfuric acid, methanesulfonic acid, phosphoric acid and oxalic acid;

preferably, the concentration of the acid solution is 5-20wt%.

7. The process according to any one of claims 1-6, wherein the alkaline substance in the alkaline liquor is selected from at least one of sodium ethoxide, sodium hydroxide, potassium carbonate and lithium hydroxide;

preferably, the molar ratio of the basic substance to the polycyanoacrylate microspheres is 0.10-1:1, preferably 0.60-1:1, based on polymerized units in the polycyanoacrylate microspheres.

8. The method of any one of claims 1-7, wherein the conditions of the partial hydrolysis reaction of step (2) comprise: the temperature is 40-80 ℃, preferably 60 ℃; the time is 2-5h, preferably 3h.

9. Polycyanoacrylic acid-cyanoacrylate embolic microspheres prepared by the preparation method according to any one of claims 1-8;

preferably, the embolic microspheres have an average particle size of 50-1000 μm;

preferably, the embolic microspheres have a polydispersity of 0.035 to 0.042.

10. Use of polycyanoacrylic acid-cyanoacrylate embolic microspheres according to claim 9 in the manufacture of a vascular embolic therapeutic drug.