Double-response type drug-loading myocardial injection emulsion gel capable of directly loading fat-soluble and water-soluble drugs and preparation method thereof

Abstract

The invention relates to double-response type drug-loading myocardial injection emulsion gel capable of directly loading fat-soluble and water-soluble drugs and a preparation method thereof, and belongs to the technical field of biomedical materials. In order to solve the problems that an existing drug-loading carrier is poor in sensitivity and accuracy to local lesions and a preparation process is complex when a fat-soluble carrier is loaded, on the basis of a pH / active oxygen dual-response framework material, vegetable oil and water are mixed to prepare an emulsion to serve as a cross-linking agent and a solvent of polyvinyl alcohol, and the pH / active oxygen dual-response framework material is prepared into the drug-loading carrier. A cross-linking agent emulsion and a polyvinyl alcohol emulsion are respectively prepared and are mixed to obtain the drug-loaded myocardial injection emulsion gel, the drug-loaded myocardial injection emulsion gel can accurately and comprehensively respond to a myocardial local lesion microenvironment to realize on-demand release, and fat-soluble and water-soluble drugs can be directly loaded at the same time. According to the invention, the high-temperature dissolution link of polyvinyl alcohol is avoided, the preparation process is simplified, the drug loading diversity and drug loading capacity are improved, and the preparation method has great practical significance and conversion prospect.

Description

Technical Field

[0001] The present invention belongs to the technical field of biomedical materials, and particularly relates to a dual-responsive drug-loaded myocardial injection emulsion gel capable of directly loading lipophilic and hydrophilic drugs and a preparation method thereof. Background Art

[0002] Microcirculation disorder after myocardial ischemia refers to a pathological state in which, after myocardial ischemia occurs, due to the structural and / or functional abnormalities of coronary microvessels, myocardial microcirculation blood perfusion is insufficient, further aggravating myocardial ischemia. In traditional drug delivery methods, after the drug reaches the microvascular system through blood circulation, its concentration and action time are difficult to precisely control, and the drug is unevenly distributed in the microvessels, resulting in poor therapeutic effects. Surgical treatment mainly targets the lesions of the main coronary artery or larger branches, and has limited direct effects on microvascular lesions.

[0003] Through tissue engineering drug-loaded materials, therapeutic factors can be directly delivered to the myocardial lesion area. However, at present, the drug release of most carriers relies on the degradation of the carrier material itself and cannot be released as needed according to the severity of the lesion area. In addition, due to the coexistence of multiple confounding factors and uneven distribution in the lesion environment, some single-responsive carrier materials are difficult to accurately identify the lesion area, resulting in omission of the lesion site.

[0004] Meanwhile, the ability of hydrogel as a drug carrier has been fully recognized, but the hydrogel carrier cannot directly load lipophilic drugs and needs to pre-embed lipophilic drugs. This will undoubtedly have many effects on the content of the loaded lipophilic drugs, drug release performance and the properties of the drugs themselves, etc., thereby affecting the overall therapeutic effect. Moreover, the embedding treatment also makes the overall preparation process more complex and is not conducive to clinical transformation.

[0005] Based on this, for the treatment of microcirculation disorder after myocardial ischemia, there is an urgent need for a drug carrier that is highly sensitive, can directly load lipophilic and hydrophilic drugs, and has a simple preparation process. Summary of the Invention

[0006] To solve the problems of poor sensitivity and accuracy of existing drug carriers to local lesions and complex preparation processes when loading lipophilic carriers, the present invention provides a dual-responsive drug-loaded myocardial injection emulsion gel capable of directly loading lipophilic and hydrophilic drugs and a preparation method thereof.

[0007] The technical solution of the present invention:

[0008] A preparation method of a dual-responsive drug-loaded myocardial injection emulsion gel capable of directly loading lipophilic and hydrophilic drugs includes the following preparation steps:

[0009] Step 1, prepare a cross-linking agent emulsion:

[0010] Mix vegetable oil with ultrapure water and subject to ultrasonic treatment to obtain an emulsion matrix. Mix the crosslinking agent (3,3'-p-boronic acid benzylammonium bromide)-methyldipropylamine with the emulsion matrix and subject to ultrasonic treatment to obtain a crosslinking agent emulsion;

[0011] Step Two: Prepare a polyvinyl alcohol emulsion:

[0012] Mix vegetable oil with ultrapure water, add polyvinyl alcohol powder, stir evenly at room temperature and then subject to ultrasonic treatment to obtain a polyvinyl alcohol emulsion;

[0013] Step Three: Prepare a drug-loaded myocardial injection emulsion gel:

[0014] Mix the crosslinking agent emulsion obtained in Step One and the polyvinyl alcohol emulsion obtained in Step Two and stir evenly to obtain a drug-loaded myocardial injection emulsion gel.

[0015] Furthermore, the vegetable oil in Step One and Step Two is both corn germ oil or olive oil, and the volume ratio of the vegetable oil to ultrapure water in Step One and Step Two is both 1:5 - 10.

[0016] Furthermore, the ultrasonic treatment time in Step One is both 5 - 20 min, and the ultrasonic power is both 300 - 500 W; the weight percentage concentration of the crosslinking agent (3,3'-p-boronic acid benzylammonium bromide)-methyldipropylamine in the crosslinking agent emulsion obtained in Step One is 1.5% w / w.

[0017] Furthermore, the alcoholysis degree of the polyvinyl alcohol powder in Step Two is 87 - 89%, the ultrasonic treatment time in Step Two is 8 - 10 min, and the ultrasonic power is both 300 - 500 W; the mass concentration of the polyvinyl alcohol in the polyvinyl alcohol emulsion obtained in Step Two is 3% w / v.

[0018] Furthermore, the volume ratio of the crosslinking agent emulsion to the polyvinyl alcohol emulsion in Step Three is 1:2.

[0019] Furthermore, it also includes adding the loaded drug in Step One and / or Step Two, and the loaded drug is a lipophilic drug and / or a water-soluble drug.

[0020] Furthermore, the lipophilic drug is a lipophilic substance that can be dissolved by corn germ oil, including curcumin, tetramethylpyrazine or tanshinone IIA; the water-soluble drugs include glutamine, VEGF-A, procyanidin B2 or coenzyme Q10; the drug loading amount of the lipophilic drug is 0.1 - 1% w / v (g / ml), and the drug loading amount of the water-soluble drug is 0.1 - 3% w / v (g / ml), specifically subject to its solubility and dosage in the corresponding solvent.

[0021] Furthermore, the preparation method of the crosslinking agent (3,3'-p-boronic acid benzylammonium bromide)-methyldipropylamine is as follows: Dissolve N'N-bis(3-aminopropyl)methylamine and 4-(bromomethyl)phenylboronic acid in a dimethylformamide solution according to a molar volume ratio of 1.5 mmol: 3.0 mmol: 20 mL, stir and react at room temperature for 5 h, add 40 mL of tetrahydrofuran at -20 °C to the obtained mixture, place the obtained mixed system at -20 °C for 8 - 12 h, collect the precipitated white solid, add 40 mL of tetrahydrofuran at -20 °C again, centrifuge at a speed of 4000 rpm for 5 min under the condition of 4 °C after oscillation, pour off the supernatant, repeat centrifugation twice, collect the centrifuged precipitate and freeze-dry for 12 h to obtain a white solid powder, which is the crosslinking agent (3,3'-p-boronic acid benzylammonium bromide)-methyldipropylamine.

[0022] Furthermore, N'N-bis(3-aminopropyl)methylamine can be replaced by 1,3-propanediamine, 2-methyl-1,3-propanediamine or 4-methylmethanediamine; 4-(bromomethyl)phenylboronic acid can be replaced by 3-methyl-4-bromomethylphenylboronic acid or 4-chloromethylphenylboronic acid.

[0023] A dual-responsive drug-loaded myocardial injection emulsion gel prepared by the preparation method of the present invention, which can directly load lipophilic and hydrophilic drugs.

[0024] The beneficial effects of the present invention:

[0025] Based on the pH / reactive oxygen species dual-responsive backbone material, the present invention uses a mixture of vegetable oil and water to form an emulsion as the solvent for the crosslinking agent and polyvinyl alcohol, and develops a dual-responsive drug-loaded myocardial injection emulsion gel that can accurately and comprehensively respond to the local pathological microenvironment of the myocardium to achieve demand-driven drug release, and can directly load lipophilic and hydrophilic drugs at the same time. In the present invention, vegetable oil provides lipophilic ability. Since vegetable oil contains polyunsaturated fatty acids and vitamin A, it has little impact on the drug carrier. Polyvinyl alcohol can act as an emulsifier to promote the formation of a stable emulsion, and at the same time, it reduces the requirement for high temperature for its own dissolution. It can be dissolved only by simple ultrasonic treatment at room temperature. Compared with the previous situation where polyvinyl alcohol needed to be dissolved at high temperature, the present invention undoubtedly greatly simplifies the preparation process and avoids the denaturation of the loaded drugs caused by high temperature. Since the high-temperature dissolution link is avoided in the overall synthesis process of the carrier, lipophilic drugs or hydrophilic drugs can be added to the crosslinking agent emulsion or polyvinyl alcohol separately or simultaneously during drug loading, thus greatly improving the drug-loading diversity and drug-loading capacity. The ratio of vegetable oil to water in the present invention can be dynamically adjusted within a certain range according to needs, further broadening the drug-loading spectrum, making the developed drug carrier truly demand-driven, and providing a "demand-driven" and "cocktail-style" drug-loading platform for the clinical treatment of myocardial ischemia-induced microcirculation disorders, which has great practical significance and transformation prospects. Description of the Drawings

[0026] Figure 1 Microscopic photograph of the microstructure of the emulsion gel prepared in Example 2 magnified 3000 times;

[0027] Figure 2 Microscopic photograph of the microstructure of the emulsion gel prepared in Example 2 magnified 6000 times;

[0028] Figure 3 Graph comparing the ratio of the remaining weight to the initial weight of the emulsion gel prepared in Example 2 daily under the conditions of pH 7.4, pH 5.0, and 10 nM H2O2;

[0029] Figure 4 Graph comparing the ratio of the viability of H9C2 cardiomyocytes when the emulsion gel prepared in Example 2 was co-cultured with H9C2 cardiomyocytes;

[0030] Figure 5 Graph of the daily drug release ratio of the emulsion gel prepared in Example 2 and the PLGA-hydrogel prepared in Comparative Example 1 under the condition of 10 nM H2O2;

[0031] Figure 6 Graph of the daily drug release ratio of the emulsion gel prepared in Example 2 and the PLGA-hydrogel prepared in Comparative Example 1 under the condition of pH 5.0. Detailed Description of the Invention

[0032] The technical solutions of the present invention will be further described below in conjunction with the embodiments, but are not limited thereto. Any modification or equivalent replacement of the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention shall be covered within the protection scope of the present invention. The process equipment or devices not specifically noted in the following embodiments are all conventional equipment or devices in the art. If not specifically indicated, the raw materials used in the embodiments of the present invention can be obtained commercially; if not specifically indicated, the technical means used in the embodiments of the present invention are all conventional means well known to those skilled in the art.

[0033] Example 1

[0034] This example provides a preparation method of a dual-responsive drug-loaded myocardial injection emulsion gel loaded with the water-soluble drug glutamine, including the following preparation steps:

[0035] Step 1: Prepare the cross-linking agent (3,3'-p-boronic acid benzyl ammonium bromide)-methyldipropylamine:

[0036] Dissolve 98% N,N-bis(3-aminopropyl)methylamine and 4-(bromomethyl)phenylboronic acid in dimethylformamide solution according to the molar volume ratio of 1.5 mmol:3.0 mmol:20 mL, stir and react at room temperature for 5 h. After the reaction, add 40 mL of tetrahydrofuran at -20°C to the obtained mixture, place the obtained mixed system in a -20°C refrigerator for 12 h, collect the precipitated white solid, add 40 mL of tetrahydrofuran at -20°C again, oscillate and centrifuge at 4000 rpm for 5 min at 4°C, pour off the supernatant, repeat centrifugation twice, collect the centrifuged precipitate and freeze-dry it in a vacuum freeze-dryer for 12 h to obtain a white solid powder, which is the cross-linking agent (3,3'-p-boronic acid benzylammonium bromide)-methyldipropylamine;

[0037] Step two: Prepare the cross-linking agent emulsion:

[0038] Mix corn germ oil and ultrapure water according to a volume ratio of 1:5, ultrasonically treat with a power of 300 W for 15 min to obtain an emulsion matrix, mix the cross-linking agent (3,3'-p-boronic acid benzylammonium bromide)-methyldipropylamine with the emulsion matrix, add glutamine, and ultrasonically treat with a power of 300 W for 5 min to obtain a drug-loaded cross-linking agent emulsion; the weight percentage concentration of the cross-linking agent (3,3'-p-boronic acid benzylammonium bromide)-methyldipropylamine in the obtained drug-loaded cross-linking agent emulsion is 1.5% w / w;

[0039] Step three: Prepare the polyvinyl alcohol emulsion:

[0040] Mix corn germ oil and ultrapure water according to a volume ratio of 1:5, then add polyvinyl alcohol powder with an alcoholysis degree of 89%, stir evenly at room temperature, and ultrasonically treat with a power of 300 W for 8 min to obtain a polyvinyl alcohol emulsion; the mass concentration of polyvinyl alcohol in the polyvinyl alcohol emulsion is 3% w / v;

[0041] Step four: Prepare the drug-loaded myocardial injection emulsion gel:

[0042] Mix the drug-loaded cross-linking agent emulsion obtained in step two and the polyvinyl alcohol emulsion obtained in step three according to a volume ratio of 1:2 and stir rapidly for 1 min to obtain a white and slightly transparent drug-loaded myocardial injection emulsion gel, where the drug loading of glutamine is 0.887% W / V (g / ml)

[0043] Example 2

[0044] This example provides a preparation method of a dual-responsive drug-loaded myocardial injection emulsion gel loaded with a lipophilic drug curcumin, including the following preparation steps:

[0045] Step one: Prepare the cross-linking agent (3,3'-p-boronic acid benzylammonium bromide)-methyldipropylamine:

[0046] Dissolve 98% N,N-bis(3-aminopropyl)methylamine and 4-(bromomethyl)phenylboronic acid in dimethylformamide solution according to the molar volume ratio of 1.5 mmol:3.0 mmol:20 mL, stir and react at room temperature for 5 h. After the reaction, add 40 mL of tetrahydrofuran at -20 °C to the obtained mixture, place the obtained mixed system in a -20 °C refrigerator for 12 h, collect the precipitated white solid, add another 40 mL of tetrahydrofuran at -20 °C, oscillate and centrifuge at 4000 rpm for 5 min at 4 °C, pour off the supernatant, repeat centrifugation twice, collect the centrifuged precipitate and freeze-dry it in a vacuum freeze-dryer for 12 h to obtain a white solid powder, which is the cross-linking agent (3,3'-p-boronic acid benzylammonium bromide)-methyldipropylamine;

[0047] Step Two: Prepare the cross-linking agent emulsion:

[0048] Mix corn germ oil and ultrapure water according to a volume ratio of 1:5, ultrasonically treat with a power of 300 W for 15 min to obtain an emulsion matrix, mix the cross-linking agent (3,3'-p-boronic acid benzylammonium bromide)-methyldipropylamine with the emulsion matrix, and ultrasonically treat with a power of 300 W for 5 min to obtain a cross-linking agent emulsion; the weight percentage concentration of the cross-linking agent (3,3'-p-boronic acid benzylammonium bromide)-methyldipropylamine in the cross-linking agent emulsion is 1.5% w / w;

[0049] Step Three: Prepare the polyvinyl alcohol emulsion:

[0050] Mix corn germ oil and ultrapure water according to a volume ratio of 1:5, add polyvinyl alcohol powder with a degree of alcoholysis of 89%, add curcumin, stir evenly at room temperature, and ultrasonically treat with a power of 300 W for 8 min to obtain a drug-loaded polyvinyl alcohol emulsion; the mass concentration of polyvinyl alcohol in the obtained drug-loaded polyvinyl alcohol emulsion is 3% w / v;

[0051] Step Four: Prepare the drug-loaded myocardial injection emulsion gel:

[0052] Mix the cross-linking agent emulsion obtained in Step Two and the drug-loaded polyvinyl alcohol emulsion obtained in Step Three according to a volume ratio of 1:2 and stir rapidly for 1 min to obtain a white and slightly transparent drug-loaded myocardial injection emulsion gel, where the drug loading amount of curcumin is 0.64% W / V (g / ml).

[0053] Example 3

[0054] This example provides a preparation method of a dual-responsive drug-loaded myocardial injection emulsion gel that simultaneously loads water-soluble drug glutamine and lipophilic drug curcumin, including the following preparation steps:

[0055] Step One: Prepare the cross-linking agent (3,3'-p-boronic acid benzylammonium bromide)-methyldipropylamine:

[0056] Dissolve 98% N'N-bis(3-aminopropyl)methylamine and 4-(bromomethyl)phenylboronic acid in a dimethylformamide solution according to the molar volume ratio of 1.5 mmol:3.0 mmol:20 mL, stir and react at room temperature for 5 h. After the reaction, add 40 mL of tetrahydrofuran at -20 °C to the obtained mixture, place the obtained mixed system in a -20 °C refrigerator for 12 h, collect the precipitated white solid, add another 40 mL of tetrahydrofuran at -20 °C, oscillate, centrifuge at 4000 rpm for 5 min at 4 °C, pour off the supernatant, repeat centrifugation twice, collect the centrifuged precipitate and place it in a vacuum freeze dryer for freeze-drying for 12 h to obtain a white solid powder, which is the crosslinking agent (3,3'-p-boronic acid benzylammonium bromide)-methyldipropylamine;

[0057] Step Two: Prepare the crosslinking agent emulsion:

[0058] Mix corn germ oil and ultrapure water according to a volume ratio of 1:5, ultrasonically treat with a power of 300 W for 15 min to obtain an emulsion matrix, mix the crosslinking agent (3,3'-p-boronic acid benzylammonium bromide)-methyldipropylamine with the emulsion matrix, add glutamine, and ultrasonically treat with a power of 300 W for 5 min to obtain a drug-loaded crosslinking agent emulsion; the weight percentage concentration of the crosslinking agent (3,3'-p-boronic acid benzylammonium bromide)-methyldipropylamine in the obtained drug-loaded crosslinking agent emulsion is 1.5% w / w;

[0059] Step Three: Prepare the polyvinyl alcohol emulsion:

[0060] Mix corn germ oil and ultrapure water according to a volume ratio of 1:5, add polyvinyl alcohol powder with an alcoholysis degree of 89%, add curcumin, stir evenly at room temperature, and ultrasonically treat with a power of 300 W for 8 min to obtain a drug-loaded polyvinyl alcohol emulsion; the mass concentration of polyvinyl alcohol in the obtained drug-loaded polyvinyl alcohol emulsion is 3% w / v;

[0061] Step Four: Prepare the drug-loaded myocardial injection emulsion gel:

[0062] Mix the drug-loaded crosslinking agent emulsion obtained in Step Two and the drug-loaded polyvinyl alcohol emulsion obtained in Step Three according to a volume ratio of 1:2 and stir rapidly for 1 min to obtain a white and slightly transparent drug-loaded myocardial injection emulsion gel, in which the drug loading amount of glutamine is 0.887% W / V (g / ml), and the drug loading amount of curcumin is 0.64% W / V (g / ml).

[0063] Example 4

[0064] This example provides a preparation method of a dual-responsive drug-loaded myocardial injection emulsion gel without loading drugs, including the following preparation steps:

[0065] Step One: Prepare the crosslinking agent (3,3'-p-boronic acid benzylammonium bromide)-methyldipropylamine:

[0066] Dissolve 98% N,N-bis(3-aminopropyl)methylamine and 4-(bromomethyl)phenylboronic acid in a dimethylformamide solution according to a molar volume ratio of 1.5 mmol:3.0 mmol:20 mL, stir and react at room temperature for 5 h. After the reaction, add 40 mL of tetrahydrofuran at -20 °C to the resulting mixture, place the obtained mixed system in a -20 °C refrigerator for 12 h, collect the precipitated white solid, add another 40 mL of tetrahydrofuran at -20 °C, oscillate, centrifuge at 4000 rpm for 5 min at 4 °C, pour off the supernatant, repeat centrifugation twice, collect the centrifuged precipitate, and freeze-dry it in a vacuum freeze-dryer for 12 h to obtain a white solid powder, which is the crosslinking agent (3,3'-p-boronic acid benzyl bromoammonium)-methyldipropylamine;

[0067] Step Two: Prepare the crosslinking agent emulsion:

[0068] Mix corn germ oil and ultrapure water according to a volume ratio of 1:5, ultrasonically treat with a power of 300 W for 15 min to obtain an emulsion matrix, mix the crosslinking agent (3,3'-p-boronic acid benzyl bromoammonium)-methyldipropylamine with the emulsion matrix, and ultrasonically treat with a power of 300 W for 5 min to obtain a crosslinking agent emulsion; the weight percentage concentration of the crosslinking agent (3,3'-p-boronic acid benzyl bromoammonium)-methyldipropylamine in the obtained crosslinking agent emulsion is 1.5% w / w;

[0069] Step Three: Prepare the polyvinyl alcohol emulsion:

[0070] Mix corn germ oil and ultrapure water according to a volume ratio of 1:5, add polyvinyl alcohol powder with an alcoholysis degree of 89%, stir evenly at room temperature, and ultrasonically treat with a power of 300 W for 8 min to obtain a polyvinyl alcohol emulsion; the mass concentration of polyvinyl alcohol in the polyvinyl alcohol emulsion is 3% w / v;

[0071] Step Four: Prepare the drug-loaded myocardial injection emulsion gel:

[0072] Mix the crosslinking agent emulsion obtained in Step Two and the polyvinyl alcohol emulsion obtained in Step Three according to a volume ratio of 1:2 and stir rapidly for 1 min to obtain a white and slightly transparent myocardial injection emulsion gel without loading drugs.

[0073] Comparative Example 1

[0074] This comparative example provides a preparation method of a polyvinyl alcohol hydrogel prepared with a PLGA-encapsulated lipophilic drug curcumin, including the following preparation steps:

[0075] Step One: The synthesis of the crosslinking agent (3,3'-p-boronic acid benzyl bromoammonium)-methyldipropylamine is the same as that in Step One of Example 2;

[0076] Step 2: Encapsulation of curcumin with PLGA:

[0077] Dissolve 240 mg of PLGA powder and 19.2 mg of curcumin (8:1 W / W) in 25 ml of dichloromethane, stir at room temperature and under ventilation for 15 min, then add 50 ml of ultrapure water, stir in a fume hood for half an hour and perform ultrasonic vibration for 10 min, repeating three times.

[0078] Centrifuge at 4000 rpm for 15 min at 4 °C to remove the upper layer of liquid to obtain a pale yellow precipitate. Vacuum freeze-dry the pale yellow precipitate for 5 hours to obtain a pale yellow powder.

[0079] Step 3: Preparation of drug-containing crosslinker solution:

[0080] Mix the crosslinker (3,3'-p-boronic acid benzylammonium bromide)-methyldipropylamine with the drug-containing PLGA in ultrapure water, and perform ultrasonic treatment at a power of 300 W for 10 min to obtain a drug-loaded crosslinker solution; the weight percentage concentration of the crosslinker (3,3'-p-boronic acid benzylammonium bromide)-methyldipropylamine in the obtained drug-loaded crosslinker solution is 1.5% w / w;

[0081] Step 4: Preparation of polyvinyl alcohol (PVA) solution:

[0082] Add 3 g of polyvinyl alcohol powder with a degree of alcoholysis of 89% to 100 ml of ultrapure water, stir and heat to 95 °C until completely dissolved, and then cool to room temperature.

[0083] Step 5: Assembly of drug-containing hydrogel:

[0084] Mix the drug-containing crosslinker solution and the PVA solution at a volume ratio of 1:2 and stir at room temperature for 1 min.

[0085] The gel material prepared in Example 2 was photographed by cryo-electron microscopy. Before photographing, it needs to be cryo-treated and sputter-coated with gold (conventional sample preparation method for cryo-electron microscopy), Figure 1 and Figure 2 are respectively the microstructural micrographs of the emulsion gel prepared in Example 2 magnified 3000 times (lower right scale bar 10 μm) and magnified 6000 times (lower right scale bar 5 μm); from Figure 1 and Figure 2 it can be seen that the obtained gel material presents a honeycomb porous morphology. This is because the crosslinker (3,3'-p-boronic acid benzylammonium bromide)-methyldipropylamine has a double-headed symmetric structure, so it will present a honeycomb porous morphology after mixing with the matrix gel; the honeycomb porous morphology is beneficial to the uniform distribution of the loaded drug, making the drug release amount after intelligent response more controllable and precise.

[0086] The emulsion gels prepared in Example 2 were respectively placed under the conditions of pH 7.4, pH 5.0 and 10 nM H2O2. The weight of the emulsion gels was measured daily for 10 days, and the ratio of the remaining weight to the initial weight was calculated daily. The results are as Figure 3 shown; through Figure 3 It can be seen that within 10 days, the ratio of the remaining weight to the initial weight of the emulsion gel in PBS (pH 7.4) buffer showed only a slight change, indicating that the emulsion gel did not degrade in a neutral environment; the ratio of the remaining weight to the initial weight of the emulsion gel under the conditions of pH 5.0 and 10 nM H2O2 showed a continuous downward trend, indicating that the emulsion gel prepared in the present invention exhibits dual-sensitive characteristics to an acidic environment and a reactive oxygen environment. After myocardial ischemia, the local microenvironment becomes acidic and the reactive oxygen increases, and the two are not evenly distributed in time and space. The dual-responsive emulsion gel prepared in the present invention can achieve more comprehensive and accurate recognition of the lesion area and realize the demand-driven release of drugs.

[0087] The emulsion gel prepared in Example 2 was co-cultured with H9C2 cardiomyocytes as the carrier group, and a blank group of H9C2 cardiomyocytes without adding the emulsion gel was set up. The viability ratio of H9C2 cardiomyocytes was measured daily for three days. The results are as Figure 4 shown. Compared with the blank group without adding the emulsion gel, the viability of H9C2 cardiomyocytes co-cultured with the emulsion gel did not decrease, indicating that the emulsion gel prepared in the present invention has good biosafety and does not affect the viability of cardiomyocytes.

[0088] The emulsion gel prepared in Example 2 and the PLGA hydrogel prepared in Comparative Example 1 were placed under the condition of 10 nM H2O2. The drug release amount was measured daily for 5 days, and the relative ratio of the drug release amounts of the two groups was obtained. The results are as Figure 5 shown; compared with the PLGA hydrogel, the emulsion gel prepared in the present invention has good drug release properties under the condition of 10 nM H2O2 and can maintain a constant drug release amount for a long time.

[0089] The emulsion gel prepared in Example 2 and the PLGA hydrogel prepared in Comparative Example 1 were placed under the condition of pH 5.0. The drug release amount was measured daily for 5 days, and the relative ratio of the drug release amounts of the two groups was obtained. The results are as Figure 6 shown. Compared with the PLGA hydrogel, the emulsion gel prepared in the present invention has good drug release properties under the condition of pH 5.0 and can maintain a constant drug release amount for a long time.

Claims

1. A preparation method of a dual-responsive drug-loaded myocardial injection emulsion gel capable of directly loading lipophilic and hydrophilic drugs, characterized in that, It includes the following preparation steps: Step 1, preparing a crosslinking agent emulsion: Mix vegetable oil and ultrapure water, and perform ultrasonic treatment to obtain an emulsion matrix. Mix the crosslinking agent (3,3'-p-boronic acid benzyl ammonium bromide)-methyl dipropylamine with the emulsion matrix, and perform ultrasonic treatment to obtain a crosslinking agent emulsion; Step 2, preparing a polyvinyl alcohol emulsion: Mix vegetable oil and ultrapure water, then add polyvinyl alcohol powder, stir evenly at room temperature, and perform ultrasonic treatment to obtain a polyvinyl alcohol emulsion; Step 3, preparing a drug-loaded myocardial injection emulsion gel: Mix the crosslinking agent emulsion obtained in Step 1 and the polyvinyl alcohol emulsion obtained in Step 2, and stir evenly to obtain a drug-loaded myocardial injection emulsion gel.

2. The preparation method of a dual-responsive drug-loaded myocardial injection emulsion gel capable of directly loading lipophilic and water-soluble drugs according to claim 1, characterized in that, The vegetable oil in Step 1 and Step 2 is both corn germ oil or olive oil, and the volume ratio of the vegetable oil to ultrapure water in Step 1 and Step 2 is both 1:5 - 10.

3. The preparation method of a dual-responsive drug-loaded myocardial injection emulsion gel capable of directly loading lipophilic and hydrophilic drugs according to claim 2, characterized in that, The ultrasonic treatment time in Step 1 is both 5 - 20 min, and the ultrasonic power is both 300 - 500 W; the weight percentage concentration of the crosslinking agent (3,3'-p-boronic acid benzyl ammonium bromide)-methyl dipropylamine in the crosslinking agent emulsion obtained in Step 1 is 1.5% w / w.

4. The preparation method of a dual-responsive drug-loaded myocardial injection emulsion gel capable of directly loading lipophilic and water-soluble drugs according to claim 3, characterized in that, The alcoholysis degree of the polyvinyl alcohol powder in Step 2 is 87 - 89%, the ultrasonic treatment time in Step 2 is 8 - 10 min, and the ultrasonic power is both 300 - 500 W; the mass concentration of the polyvinyl alcohol in the polyvinyl alcohol emulsion obtained in Step 2 is 3% w / v.

5. The preparation method of a dual-responsive drug-loaded myocardial injection emulsion gel capable of directly loading lipophilic and hydrophilic drugs according to claim 4, characterized in that, The volume ratio of the crosslinking agent emulsion to the polyvinyl alcohol emulsion in Step 3 is 1:

2.

6. The preparation method of a dual-responsive drug-loaded myocardial injection emulsion gel capable of directly loading lipophilic and water-soluble drugs according to claim 5, characterized in that, It also includes adding the loaded drug in Step 1 and / or Step 2, and the loaded drug is a lipophilic drug and / or a water-soluble drug.

7. The preparation method of a dual-responsive drug-loaded myocardial injection emulsion gel capable of directly loading lipophilic and water-soluble drugs according to claim 6, characterized in that, The lipophilic drug is curcumin, ligustrazine or tanshinone IIA; the water-soluble drugs include glutamine, VEGF-A, procyanidin B2 or coenzyme Q10; the drug loading amount of the lipophilic drug is about 0.1 - 1% w / v, and the drug loading amount of the water-soluble drug is about 0.1 - 3% w / v.

8. The preparation method of a dual-responsive drug-loaded myocardial injection emulsion gel capable of directly loading lipophilic and hydrophilic drugs according to claim 7, characterized in that, The preparation method of the crosslinking agent (3,3'-p-boronic acid benzyl ammonium bromide)-methyl dipropylamine is: dissolve N'N-bis(3-aminopropyl)methylamine and 4-(bromomethyl)phenylboronic acid in a dimethylformamide solution according to a molar volume ratio of 1.5 mmol:3.0 mmol:20 mL, stir and react at room temperature for 5 h, add 40 mL of tetrahydrofuran at -20°C to the obtained mixture, place the obtained mixed system at -20°C for 8 - 12 h, collect the precipitated white solid, add another 40 mL of tetrahydrofuran at -20°C, oscillate, and centrifuge at 4000 rpm for 5 min at 4°C, pour off the supernatant, repeat centrifugation twice, collect the centrifuged precipitate and freeze-dry for 12 h to obtain a white solid powder, which is the crosslinking agent (3,3'-p-boronic acid benzyl ammonium bromide)-methyl dipropylamine.

9. The preparation method of a dual-responsive drug-loaded myocardial injection emulsion gel capable of directly loading lipophilic and hydrophilic drugs according to claim 8, characterized in that, The N'N-bis(3-aminopropyl)methylamine can be replaced by 1,3-propanediamine, 2-methyl-1,3-propanediamine or 4-methylmethanediamine; the 4-(bromomethyl)phenylboronic acid can be replaced by 3-methyl-4-bromomethylphenylboronic acid or 4-chloromethylphenylboronic acid.

10. A dual-responsive drug-loaded myocardial injection emulsion gel that can directly load lipophilic and water-soluble drugs and is prepared by the preparation method according to any one of claims 1-9.

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