A kind of sodium aescinate liposome and preparation method thereof

Abstract

The present invention relates to the field of medical technology, specifically, sodium aescinate is used as the main drug, and also includes lecithin, cholesterol and DSPE-PEG2000, and sodium aescinate is encapsulated in liposomes, which solves the defect that sodium aescinate is highly irritating and affects clinical use. The present invention is aimed at the physicochemical properties of sodium aescinate itself, and the matching study of the prescription composition and the preparation process is carried out. In a real sense, a sodium aescinate liposome with minimal irritation, safety, stable quality and simple preparation process is developed, which lays a solid foundation for the further research and application of sodium aescinate.

Description

Technical Field

[0001] The invention relates to the technical field of medicine, in particular to a sodium aescinate liposome and a preparation method thereof. Background Art

[0002] Sodium aescinate is a sodium salt of triterpenoid saponin extracted from the dried mature fruit of Aesculus Wilsonii Rehd., a plant of the Aesculaceae family. This product is a white powder or crystalline powder, bitter and spicy, hygroscopic, easily soluble in water, and slightly soluble in ethanol. Sodium aescinate is a new generation of anti-inflammatory, anti-osmotic and detumescent drugs. Sodium aescinate can promote the secretion of PGE-2 in the blood vessel wall, remove free radicals in the body, thereby playing an anti-inflammatory, anti-osmotic, accelerating venous blood flow, promoting lymphatic reflux, increasing venous tension, improving blood circulation and microcirculation, and protecting the blood vessel wall. Its clinical efficacy is significant. This drug was successfully developed in my country in the 1980s and used in clinical practice. It is mainly used to treat edema and hematoma in various parts of the human body caused by various reasons; acute and chronic injuries of various tissues, fractures, trauma, brain dysfunction caused by various reasons such as brain trauma, cerebrovascular disease, stroke, brain tumor, cerebrovascular disease, intracranial infection, etc.; local blood circulation disorders caused by various vascular diseases, etc. Clinical experiments have proven that sodium aescinate has a stable and long-lasting effect, can greatly shorten the course of treatment, relieve patients' pain, avoid water and electrolyte disorders and renal damage, overcome the rebound of mannitol and the side effects of corticosteroids, and has excellent clinical efficacy. It is a safe, effective and reliable anti-inflammatory and detumescent drug.

[0003] Sodium aescinate liniment, gel, tablet, freeze-dried powder injection, etc. have been widely used in anti-inflammatory and detumescent treatment. Among them, sodium aescinate liniment and gel as external preparations have good efficacy in treating acute closed soft tissue injuries such as sprains, ecchymoses and pressure injuries of tendons, muscles, ligaments and joints. However, due to the limitations of external preparations, sodium aescinate cannot be used to deeply treat brain dysfunction caused by various reasons such as brain trauma, stroke, cerebrovascular disease, brain tumor, intracranial infection, etc. and local blood circulation disorders caused by various vascular diseases. At the same time, since sodium aescinate belongs to the triterpenoid saponin drugs containing multiple ester bonds, it has strong irritation and cannot be used on damaged skin and mucous membranes, and may cause local pain and allergic reactions during use. Sodium aescinate tablets have poor oral absorption and low bioavailability. Large doses will burden the kidneys and cannot be used for comatose patients, which has certain limitations. Sodium aescinate for injection has the advantages of rapid onset and long-lasting biological effects. After a single dose, the anti-inflammatory and anti-exudative activities can be maintained for more than 16 hours, which can effectively treat and prevent postoperative edema and relieve patients' pain. However, due to its strong irritation and the physical and chemical properties of saponins, this preparation has many defects: ① Sodium aescinate is a sodium salt of triterpenoid saponin, which itself has a strong irritation to blood vessels. Intravenous injection can cause pain at the injection site, and long-term use may cause phlebitis. Strict observation is required during the infusion process to prevent the liquid from leaking into the surrounding tissues and causing redness and swelling. As reported in the following literature: (Liu Mingjie. Clinical application, adverse reactions and pharmacological research of sodium aescinate [J]. Lishizhen Traditional Chinese Medicine, 2005(11):1158-1160; Wang Qiyun. Clinical application and adverse reactions of sodium aescinate for injection [J]. Clinical Medical Practice, 2009,18(11):1596-1597.); ② It is easy to cause hemolytic reaction during infusion (Wu Fengzhi et al. Osmotic pressure analysis of three infusion combinations of sodium aescinate for injection [J]. China Pharmaceutical Industry, 2020,29(11):42-43); ③ It has strong renal function damage and often causes rash during infusion; a thicker intravenous injection is required for infusion; ④ Foam is easy to appear during preparation, which is inconvenient to prepare. In view of the many problems existing in sodium aescinate for injection, how to develop sodium aescinate intravenous preparations with less irritation, good safety, convenient use and easy preparation has become a hot topic in the research of sodium aescinate preparations.

[0004] In view of the shortcomings of the existing sodium aescinate preparations, domestic and foreign scholars have conducted extensive research on sodium aescinate liposomes or other nano preparations. We know that nano preparations have a passive targeting effect on inflammation, which can significantly improve the efficacy and reduce toxic side effects. Sodium aescinate nano preparations have become a hot topic in the field of medicine. Patent CN200510089090.7 provides a nano aescinate injection preparation and a preparation method thereof. The article explores the compatibility of different lipids and emulsifiers. The nano injection prepared by the compatibility of stearic acid and soybean lecithin has good morphology, stability, etc. However, the nano preparation has the defects of complex preparation process, reasonable ratio, high processing difficulty, high cost, and difficulty in large-scale promotion. In addition, from the perspective of the formulation process of the preparation, the preparation is theoretically a solid lipid nanoparticle, and the safety of solid lipid nanoparticles formed by solid lipid stearic acid for intravenous administration needs further study. Literature (Li Ziwei, et al. Preparation and quality evaluation of sodium aescinate microemulsion injection [J]. Journal of Sichuan University (Medical Edition), 2014, 45(01): 147-151; Qin Yao, et al. Safety and pharmacodynamics study of sodium aescinate microemulsion injection [J]. Chinese Modern Applied Pharmacy, 2013, 30(10): 1043-1046.) and patent CN201210338585.9, developed a sodium aescinate microemulsion, the microemulsion formula contains a large amount of surfactant, which further increases the incidence of sodium aescinate vascular irritation and hemolysis. Patents CN200610027444.X and CN201510304196.8 both provide a method for preparing a freeze-dried sodium aescinate emulsion, but the preparation and freeze-drying process of the freeze-dried emulsion are complicated, and a large amount of surfactant will be added during the preparation of the emulsion, which may cause more severe vascular irritation and hemolysis, and the encapsulation rate of the water-soluble sodium aescinate encapsulated in the emulsion will be relatively low, thereby affecting the performance of its in vivo effects. It can be seen that the feasibility of preparing sodium aescinate into conventional encapsulated preparations such as nano injections, microemulsions or freeze-dried emulsions is far from satisfactory, mainly because sodium aescinate is a water-soluble drug with poor encapsulation, microemulsions increase the safety risks of vascular irritation and hemolysis, and the preparation process of nano injections and freeze-dried emulsions is complicated.

[0005] Liposomes were proposed by Bangham in the mid-1960s. In the early 1970s, Gregoriadis first proposed the use of liposomes as β-galactosidase carriers to treat glycogen accumulation diseases. Since then, liposomes have received widespread attention as a drug delivery carrier. The phospholipid bilayer of liposomes is similar to biological membranes, has good biocompatibility and low toxicity, and is now widely used in cancer, fungal treatment, and viral infections. To this end, we intend to use liposome technology to reduce the direct contact between drugs and blood vessel walls, thereby fundamentally solving the problem of strong irritation and hemolysis of sodium aescinate, and achieving the research goal of high efficiency, low irritation, and low hemolysis.

[0006] Through literature search, there have been reports on sodium aescinate liposomes at home and abroad. Patent CN202011530050.2 has developed a sodium aescinate anti-edema and analgesic compound preparation. The article involves a method for preparing sodium aescinate liposomes. The liposomes use a ratio of sodium aescinate to membrane material of 1:30-40 (weight ratio), and the molar ratio of phospholipids to cholesterol is 5:2. However, its preparation process is complicated, and it is necessary to use a sodium aescinate aqueous solution and a membrane material ethanol solution to dissolve and then form a film. This feature is difficult to achieve in process amplification, and the industrial operability is poor. In addition, repeated extrusion is required during the preparation process, up to 15 times, which has a certain impact on the stability of the preparation. This patent uses DEPC saline for hydration, but DEPC water needs to be sterilized by high pressure before being prepared into DEPC saline. This process is complicated and cumbersome, and there are safety hazards; the process of using a shaker and ultrasonic hydration is complicated. In addition, this article does not characterize the prescriptions of liposomes with different ratios, and does not evaluate the correlations such as efficacy and safety, which shows that it has not conducted a systematic study on liposomes. Patents CN201710325262.9 and CN201710324980.4 both mention a method for preparing a hydrogel patch of sodium aescinate liposomes, which uses 20-50% ethanol to dissolve lipid membrane materials and drugs, and prepares liposomes by thin film dispersion. We prepared it in the same way as shown in Example 1 of patent CN201710324980.4. During the preparation process, we found that it was difficult to form a film by adding 30% ethanol, and 70% of water was almost difficult to evaporate at 45°C. The rotation speed was appropriately increased. Due to the nature of aescin itself, a large number of bubbles will be generated and sucked back. Therefore, there are great loopholes in the method of this patent embodiment, which needs to be discussed. Patents CN201710212793.7, CN201710212717.6 and CN201710212709.1 disclose a topical preparation of aescin liposome gel to improve the poor transdermal properties and high skin irritation of sodium aescin. All of the above adopt the ethanol injection method to prepare liposomes. Although the preparation method is simple and technically feasible, the particle size of the liposomes prepared by the formula and process adopted is greater than 300nm or even greater than 500nm, and the particle size is large. Moreover, the encapsulation rate of the prepared liposomes is almost less than 90%, which will directly affect the stability of the drug-loaded liposomes. We still prepared Example 1 shown in patent CN201710212793.7, and the encapsulation rate obtained by the preparation is basically consistent with that shown in the patent, but it is found that the drug loss before and after ultrafiltration is large, which further illustrates that the topical aescin liposome has not yet perfected the matching research of the prescription process of the liposome and the drug, so as to achieve a smaller particle size, a higher encapsulation rate, and less drug ultrafiltration loss.The literature (De Groot C, Musken M, Muller-Goymann CC. Novel Colloidal Microstructures of beta-Escin and the Liposomal Components Cholesterol and DPPC[J]. Planta Med, 2018, 84(16): 1219-1227.) prepared sodium aescinate liposomes by thin film dispersion method and discussed the interaction between β-sodium aescinate, cholesterol and DPPC. However, the literature did not conduct a systematic study on the relationship between the formulation and process of β-sodium aescinate liposomes and the encapsulation efficiency, drug release, in vivo efficacy, hemolysis and vascular irritation of liposomes. The literature (Li Ziwei. Research on liposome inflammatory lesion delivery system constructed by fMLP modified cholesterol [D]. Chongqing Medical University, 2014.) provides a method for preparing fMLP (leukocyte chemotactic peptide) modified sodium aescinate liposomes to improve the targeting of liposomes to inflammatory lesions. The paper uses a thin film dispersion method to prepare liposomes. The formulation process study shows that when the cholesterol: phospholipid ratio (molar ratio) is 2:1, 1:1, 1:2, and 1:4, respectively, the drug encapsulation rates are 54.06%, 70.45%, 79.42% and 72.31%; when the drug-lipid ratio (mass ratio) was 1:6, 1:3 and 1:1 respectively, the drug encapsulation rates were 77.34%, 79.42% and 30.23% respectively, and the encapsulation rate of the final optimized formula was (80.1±4.8)%. It can be seen that the encapsulation rate of the prepared liposomes is generally not high, indicating that the prescription process has not yet reached the optimization level, and the thin film dispersion method may cause residual organic solvent chloroform and bring harm to the human body.

[0007] It can be seen that the current process technology of sodium aescinate liposomes for external use and sodium aescinate liposomes for intravenous administration is still very immature, and due to the imperfections in the formulation process, the particle size, encapsulation rate, stability, vascular irritation, hemolysis and other aspects of the prepared drug-loaded liposomes have not been fundamentally improved. Summary of the invention

[0008] Since the above dosage forms do not fundamentally improve the defects of sodium aescinate in terms of strong irritation and high hemolysis, the purpose of the present invention is to provide a safe, efficient and stable quality sodium aescinate liposome. Another purpose of the present invention is to provide a method for preparing sodium aescinate liposome.

[0009] The first aspect of the present invention provides a sodium aescinate liposome, which uses sodium aescinate as an active ingredient and also includes lecithin, cholesterol and DSPE-PEG2000; wherein the amount of sodium aescinate is 0.1-0.5% (w / v); the amount of lecithin is 1-10% (w / v); the amount of cholesterol is 0.5-5% (w / v); and the amount of DSPE-PEG2000 is 0-1% (w / v).

[0010] Furthermore, the amount of lecithin used is 2-7% (w / v); the amount of cholesterol used is 1-3% (w / v); and the amount of DSPE-PEG2000 used is 0.01-0.3% (w / v).

[0011] Furthermore, the sodium aescinate liposome is an injection, preferably a lyophilized powder injection.

[0012] Furthermore, the organic solvent for injection of the injection is selected from one or more of anhydrous ethanol, propylene glycol, and tert-butyl alcohol, preferably anhydrous ethanol, and the dosage is 7-15% g / ml, more preferably 9-13% g / ml.

[0013] Furthermore, in the sodium aescinate liposome, the drug-lipid ratio is 1:5-1:30 g / g, the lecithin: cholesterol ratio is 1:1-5:1 g / g, and the pH value is 2.0-4.8.

[0014] Furthermore, the sodium aescinate liposomes are composed of sodium aescinate, lecithin, cholesterol, DSPE-PEG2000, a lyophilization protectant and a pH regulator.

[0015] Furthermore, the sodium aescinate liposome is prepared by the following formula:

[0016]

[0017] Furthermore, the sodium aescinate liposome is prepared by the following formula:

[0018]

[0019]

[0020] Furthermore, the lecithin is selected from one or more of egg yolk lecithin, high-purity egg yolk lecithin, hydrogenated soybean lecithin, distearoyl phosphatidylcholine, distearoyl phosphatidylglycerol, dipalmitoyl phosphatidylcholine, soybean lecithin, phosphatidylserine, dimyristoyl phosphatidylcholine, phosphatidylethanolamine, and sphingomyelin; preferably, high-purity egg yolk lecithin is used.

[0021] Furthermore, the lyophilization protective agent is selected from one or more of sucrose, trehalose, maltose, glucose, lactose, mannitol, sorbitol, xylitol, erythritol, and threonine. Preferably, one or more of sucrose, trehalose, and maltose are used in combination.

[0022] Furthermore, the pH adjuster is selected from one or more of citric acid, hydrochloric acid, sodium hydroxide, phosphoric acid, disodium hydrogen phosphate, disodium phosphate, dipotassium hydrogen phosphate, disodium citrate, trisodium citrate; preferably one or more of citric acid and hydrochloric acid. The pH value is adjusted to 2.0-4.8, preferably to 2.5-4.5.

[0023] The second aspect of the present invention provides a method for preparing the sodium aescinate liposome as described above, wherein the method is an injection method. The method comprises the following steps:

[0024] Weigh the prescribed amount of lecithin, cholesterol, and DSPE-PEG2000, place them in an organic solvent, heat and dissolve them at 50-65°C to obtain an organic phase; weigh the prescribed amount of sodium aescinate, dissolve them in an appropriate amount of water for injection, keep them warm at 50-65°C, adjust the pH with a pH regulator to obtain an aqueous phase; inject the organic phase into the aqueous phase under stirring conditions, mix them evenly, and dilute the volume to the prescribed amount with water for injection to obtain a crude liposome; emulsify the crude liposome by using probe ultrasound, or place it in an extruder and extrude it through an extrusion membrane several times, or place it in a high-pressure homogenizer for homogenization and emulsification to obtain a liposome solution. Add an equal amount of water for injection or an equal amount of water for injection after adjusting the pH to ultrafilter several times to remove the organic solvent; weigh the prescribed amount of lyophilization protective agent, place it in the above liposome solution, stir to dissolve it, sterilize it through a 0.22μm filter membrane, divide it into portions, lyophilize it, and cap it to obtain a sodium aescinate liposome lyophilized powder injection.

[0025] Furthermore, in the preparation method, the pH adjuster is selected from one or more of citric acid, hydrochloric acid, sodium hydroxide, phosphoric acid, disodium hydrogen phosphate, disodium phosphate, dipotassium hydrogen phosphate, disodium citrate, and trisodium citrate; preferably, one or more of citric acid and hydrochloric acid are used in combination to adjust the pH value to 2.0-4.8, and preferably the pH value is adjusted to 2.5-4.5.

[0026] Furthermore, in the preparation method, the organic solvent for injection is selected from one or more of anhydrous ethanol, propylene glycol, and tert-butyl alcohol, preferably anhydrous ethanol, and the dosage is 7-15% g / ml; more preferably 9-13% g / ml.

[0027] Furthermore, in the preparation method, the organic solvent for injection can be removed by ultrafiltration after the crude liposome is emulsified, or can be removed during the freeze-drying process. Preferably, ultrafiltration is used for removal, and the dialysate can be either water for injection or water for injection after adjusting the pH to 2.0-4.8, preferably 2.5-4.5.

[0028] Furthermore, in the preparation method, the injection method can be injecting the oil phase into the water phase, or injecting the water phase into the oil phase.

[0029] Furthermore, in the preparation method, the crude liposome is emulsified, and the pore size of the extrusion membrane is selected from 0.8 μm, 0.6 μm, 0.4 μm, 0.2 μm, 0.1 μm, 0.08 μm, and 0.05 μm, and one or more of them are sequentially extruded through large pores to small pores. The preferred extrusion membrane is 0.2 μm and 0.1 μm.

[0030] The average particle size of the sodium aescinate liposome of the invention is 70-200nm.

[0031] The third aspect of the present invention provides a use of the sodium aescinate liposomes as described above in the preparation of anti-inflammatory drugs.

[0032] The sodium aescinate liposomes of the present invention show a better therapeutic effect than sodium aescinate for injection at the same clinical dose.

[0033] The present invention has the advantages that:

[0034] 1. The present invention encapsulates sodium aescinate in liposomes, thereby solving the problem that sodium aescinate has a strong irritant and thus affects its clinical use.

[0035] 2. The sodium aescinate liposome provided by the present invention has a high encapsulation rate and good stability.

[0036] 3. The sodium aescinate liposome provided by the present invention has better anti-inflammatory effect.

[0037] 4. The present invention aims at the physicochemical properties of sodium aescinate itself, and conducts a matching study on the prescription composition and the preparation process. Through the matching prescription process, the problems of strong irritation and easy hemolysis of sodium aescinate for injection are truly overcome, and a sodium aescinate liposome with minimal irritation, safety, stable quality and simple preparation process is developed, which lays a foundation for the further research and application of sodium aescinate. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 . Parallel comparison of hemolytic activity of different embodiments;

[0039] Figure 2 . Comparison of irritation of different embodiments. DETAILED DESCRIPTION

[0040] The specific embodiments provided by the present invention are described in detail below in conjunction with the examples. It should be understood that the following examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention. Based on the fact that the encapsulation efficiency after liposome ultrafiltration is about 99%, the encapsulation efficiency described in the following examples all refers to the encapsulation efficiency before ultrafiltration in order to reflect the rationality of the liposome formulation process.

[0041] Example 1: The criticality of aqueous phase pH to the development of sodium aescinate liposomes

[0042] 1. Experimental prescription

[0043] Table 1 Prescription design of experimental verification scheme

[0044]

[0045] 2. Preparation process

[0046] Weigh the prescribed amount of high-purity egg yolk phosphatidylcholine (EPCS), cholesterol, and DSPE-PEG2000, place them in 11.00g of anhydrous ethanol, and heat them at 65°C to dissolve them to obtain an organic phase; weigh 0.25g of the prescribed amount of sodium aescinate, dissolve them in 82g of water for injection, keep them warm at 65°C, and use citric acid to adjust the pH to obtain an aqueous phase; inject the organic phase into the aqueous phase under stirring conditions, mix them evenly, and make up the volume to 100mL with the corresponding water for injection after adjusting the pH to obtain a crude liposome; extrude the crude liposome through a 0.2μm extrusion membrane for 2 times, and then extrude it through a 0.1μm extrusion membrane for 5 times to obtain a liposome solution; add an equal amount of water for injection and ultrafilter for 4 times to remove the organic solvent; weigh 12g of sucrose, place it in the above liposome solution, stir to dissolve it, sterilize it through a 0.22μm filter membrane, divide it into portions, freeze-dry it, and cap it to obtain a sodium aescinate liposome freeze-dried powder injection.

[0047] 3. Experimental results

[0048] Since the encapsulation rate of water-soluble drugs is generally low, we mainly use the encapsulation rate as the main indicator. When we conducted a parallel comparison of a series of sodium aescinate liposomes with different aqueous phase pH, we found that the aqueous phase pH had a significant effect on the encapsulation rate. When the aqueous phase pH is less than 2.0, the acidity is too strong and it is not suitable for intravenous administration; when the aqueous phase pH is between 2.0-4.8, the encapsulation rate is above 90%, and when the aqueous phase pH is greater than 4.8, the encapsulation rate will be significantly reduced. The results are shown in Table 2 below.

[0049] Table 2 Effect of aqueous phase pH on the drugability of sodium aescinate liposomes

[0050] Group Appearance Encapsulation rate (%) Particle size PDI Prescription 1 Translucent homogeneous solution 97.84 124.6 0.145 Prescription 2 Translucent homogeneous solution 98.31 115.3 0.112 Prescription 3 Translucent homogeneous solution 97.06 111.7 0.103 Prescription 4 Translucent homogeneous solution 94.53 108.4 0.117 Prescription 5 Translucent homogeneous solution 90.27 105.7 0.115 Prescription 6 Translucent homogeneous solution 82.66 103.6 0.108

[0051] Result analysis: After a large number of experimental verifications, we obtained the above experimental results. We found that the pH of the aqueous phase will directly affect the encapsulation of sodium aescinate. The encapsulation rate of sodium aescinate liposomes is closely related to the pH value of the aqueous phase. It can be seen that the regulation of the pH of the aqueous phase is crucial for this liposome and will directly affect the drugability of the liposome.

[0052] Example 2: Evaluation of different dialysates of prescription 3 in Example 1 on sodium aescinate liposomes

[0053] 1. Preparation process

[0054] Prescription 3 in Example 1 was selected to prepare sodium aescinate liposomes, and water for injection and water for injection after pH adjustment (pH 3.5) were used as dialysates to remove the organic solvent. The remaining preparation steps were the same as those of the preparation method of Prescription 3 in Example 1.

[0055] 2. Effects of different dialysates on drug loss before and after ultrafiltration and encapsulation efficiency of sodium aescinate liposomes after ultrafiltration

[0056] Table 3 Drug loss before and after ultrafiltration and encapsulation efficiency after ultrafiltration of sodium aescinate liposomes by different dialysates

[0057] Dialysate Before ultrafiltration (mg / mL) After ultrafiltration (mg / mL) loss% Encapsulation rate after ultrafiltration % Water for injection 2.35 2.27 3.40 99.21 Water for injection after pH adjustment (pH 3.5) 2.35 2.26 3.83 99.46

[0058] Analysis of results: We analyzed and verified the results of ultrafiltration of two types of dialysate to remove organic solvents, and found that whether the dialysate was water for injection or water for injection after adjusting the pH, it had no significant effect on the drug loss before and after ultrafiltration of sodium aescinate liposomes and the encapsulation rate after ultrafiltration. Therefore, either water for injection or water for injection after adjusting the pH can be used as the dialysate.

[0059] Example 3: The criticality of the amount of organic solvent for injection in the development of sodium aescinate liposomes

[0060] 1. Experimental prescription

[0061] Table 4 Prescription design of experimental verification scheme

[0062]

[0063] 2. Preparation process

[0064] Weigh the prescribed amount of high-purity egg yolk phosphatidylcholine (EPCS), cholesterol, and DSPE-PEG2000, place them in anhydrous ethanol, and heat them at 55°C to dissolve them to obtain an organic phase; weigh 0.25g of the prescribed amount of sodium aescinate, dissolve them in water for injection, keep them warm at 55°C, and use citric acid to adjust the pH to 3.5 to obtain an aqueous phase; inject the organic phase into the aqueous phase under stirring conditions, mix them evenly, and make up the volume to 100mL with the corresponding water for injection after adjusting the pH, so as to obtain a crude liposome; extrude the crude liposome through a 0.2μm extrusion membrane for 2 times, and then extrude it through a 0.1μm extrusion membrane for 5 times to obtain a liposome solution; add an equal amount of water for injection and ultrafilter for 4 times to remove the organic solvent; weigh 12g of sucrose, place it in the above liposome solution, stir to dissolve it, sterilize it through a 0.22μm filter membrane, divide it into portions, freeze-dry it, and cap it to obtain a sodium aescinate liposome freeze-dried powder injection.

[0065] 3. Experimental results

[0066] The appearance, encapsulation efficiency and 0.22 μm filter membrane filtration smoothness of the above liposomes were investigated, and the results are shown in Table 5 below.

[0067] Table 5 Effect of the dosage of organic solvent for injection on sodium aescinate liposomes

[0068]

[0069]

[0070] The experimental results show that different amounts of organic solvents for injection have a greater impact on the encapsulation efficiency of sodium aescinate liposomes, which is another important reason why this preparation has a higher encapsulation efficiency. When the content of the organic solvent for injection is small, cholesterol cannot be completely dissolved even under heating, affecting the drugability of the liposome. When the content of the organic solvent for injection is large, the encapsulation efficiency of the prepared sodium aescinate liposomes is low, affecting the quality, so the appropriate amount of organic solvent for injection is the key to the present invention.

[0071] Example 4: Comparative evaluation of sodium aescinate liposomes prepared with different phospholipid to cholesterol ratios

[0072] 1. Preparation of sodium aescinate liposomes with different phospholipid to cholesterol ratios

[0073] Table 6 Prescription design of experimental verification scheme

[0074]

[0075] 2. Preparation process

[0076] Weigh the prescribed amount of high-purity egg yolk phosphatidylcholine (EPCS), cholesterol, and DSPE-PEG2000, place them in 11.00g of anhydrous ethanol, and heat them at 55°C to dissolve them to obtain an organic phase; weigh 0.25g of sodium aescinate in the prescribed amount and dissolve them in 82g of water for injection, keep them warm at 55°C, and use citric acid to adjust the pH to 3.3 to obtain an aqueous phase; inject the organic phase into the aqueous phase under stirring conditions, mix them evenly, and make up the volume to 100mL with the corresponding water for injection after adjusting the pH to obtain a crude liposome; extrude the crude liposome through a 0.2μm extrusion membrane for 2 times, and then extrude it through a 0.1μm extrusion membrane for 5 times to obtain a liposome solution; add an equal amount of water for injection and ultrafilter for 4 times to remove the organic solvent; weigh 12g of sucrose, place it in the above liposome solution, stir to dissolve it, sterilize it through a 0.22μm filter membrane, divide it into portions, freeze-dry it, and cap it to obtain a sodium aescinate liposome freeze-dried powder injection.

[0077] Table 7 Effect of different phospholipid to cholesterol ratios on sodium aescinate liposomes

[0078] Group Encapsulation rate (%) Particle size nm PDI Prescription 1 90.36 103.4 0.176 Prescription 2 91.03 107.7 0.183 Prescription 3 97.51 110.1 0.102 Prescription 4 96.78 111.6 0.104

[0079] After a series of parallel comparisons of experimental results, it was found that when the ratio of lecithin to cholesterol is too small, the extrusion pressure of the preparation will be too high and it cannot be extruded smoothly. When the ratio of lecithin to cholesterol is too large, it will directly affect the encapsulation rate of sodium aescinate liposomes. The encapsulation rate decreases with the increase of the ratio of the two, and it will cause the PDI to increase, affecting the stability of the preparation.

[0080] Example 5: Comparative evaluation of sodium aescinate liposomes prepared with different drug-lipid ratios

[0081] 1. Preparation of sodium aescinate liposomes with different drug-lipid ratios

[0082] Table 8 Prescription design of experimental verification scheme

[0083]

[0084] 2. Preparation process

[0085] Weigh the prescribed amount of high-purity egg yolk phosphatidylcholine (EPCS), cholesterol, and DSPE-PEG2000, place them in 11.00g of anhydrous ethanol, and heat them at 60°C to dissolve them to obtain an organic phase; weigh 0.25g of the prescribed amount of sodium aescinate, dissolve them in 81g of water for injection, keep them warm at 60°C, and use citric acid to adjust the pH to 3.6 to obtain an aqueous phase; inject the organic phase into the aqueous phase under stirring conditions, mix them evenly, and make up to 100mL with the corresponding water for injection after adjusting the pH to obtain a crude liposome; extrude the crude liposome through a 0.2μm extrusion membrane for 2 times, and then extrude it through a 0.1μm extrusion membrane for 5 times to obtain a liposome solution; add an equal amount of water for injection and ultrafilter for 4 times to remove the organic solvent; weigh 12g of sucrose, place it in the above liposome solution, stir to dissolve it, sterilize it through a 0.22μm filter membrane, divide it into portions, freeze-dry it, and cap it to obtain a sodium aescinate liposome freeze-dried powder injection.

[0086] 3. Drug loss before and after ultrafiltration of sodium aescinate liposomes with different drug-lipid ratios

[0087] Table 9 Drug loss before and after ultrafiltration of sodium aescinate liposomes with different drug-lipid ratios

[0088] Before ultrafiltration (mg / mL) After ultrafiltration (mg / mL) loss% Drug-lipid ratio 1:5 2.46 2.20 10.57 Drug-lipid ratio 1:10 2.49 2.38 4.42 Drug-lipid ratio 1:15 2.28 2.19 3.94 Drug-lipid ratio 1:20 2.39 2.31 3.35 Drug-lipid ratio 1:30 2.45 2.38 2.86

[0089] Results analysis: Different drug-lipid ratios have a significant effect on drug loss. When the drug-lipid ratio is large, drug loss is obvious, resulting in process instability. By increasing the lipid ratio to a certain extent, we unexpectedly found that when the drug-lipid ratio increases to between 1:10 and 1:30, the drug loss before and after ultrafiltration tends to a plateau. However, we prefer a drug-lipid ratio of 1:10 to 1:20 based on the addition of fewer excipients and the reduction of economic costs.

[0090] Example 6: Preparation of sodium aescinate liposomes

[0091] Weigh 3 g of high-purity egg yolk phosphatidylcholine (EPCS), 1.5 g of cholesterol, and 0.1 g of DSPE-PEG20000 in the prescribed amount, place them in 11.00 g of anhydrous ethanol, and heat them at 65°C to dissolve them to obtain an organic phase; weigh 0.25 g of sodium aescinate in the prescribed amount and dissolve them in 82 g of water for injection, adjust the pH value to 3.5 with citric acid, and keep warm at 55°C to obtain an aqueous phase; inject the organic phase into the aqueous phase under stirring, mix well, and use water for injection The volume was adjusted to 100 mL to obtain crude liposomes; the crude liposomes were homogenized 3 times by a high-pressure homogenizer at pressures of 15000 psi, 20000 psi and 25000 psi, respectively, to obtain a liposome solution; an equal amount of water for injection was added and ultrafiltered 4 times to remove the organic solvent; 12 g of sucrose was weighed and placed in the above liposome solution, stirred to dissolve, sterilized by filtering through a 0.22 μm filter membrane, packaged, freeze-dried, and capped to obtain sodium aescinate liposome freeze-dried powder injection.

[0092] It was determined that the encapsulation efficiency was 96.85%, the particle size was 153.4 nm, and the PDI was 0.178.

[0093] Example 7: Preparation of sodium aescinate liposomes

[0094] Weigh 3g of high-purity egg yolk phosphatidylcholine (EPCS), 1.5g of cholesterol, and 0.1g of DSPE-PEG20000 in the prescribed amount, place them in 11.00g of anhydrous ethanol, and heat them at 65°C to dissolve them to obtain an organic phase; weigh 0.25g of sodium aescinate in the prescribed amount, dissolve them in 82g of water for injection, adjust the pH value to 3.5 with citric acid, and keep warm at 55°C to obtain an aqueous phase; inject the organic phase into the aqueous phase under stirring, mix well, and dilute to 100mL with water for injection to obtain a crude liposome; extrude the crude liposome through a 0.2μm extrusion membrane for 2 times, and then extrude it through a 0.1μm extrusion membrane for 5 times to obtain a liposome solution; add an equal amount of water for injection and ultrafilter for 5 times to remove the organic solvent; weigh 12g of sucrose, place it in the above liposome solution, stir to dissolve it, sterilize it through a 0.22μm filter membrane, divide it into portions, freeze-dry it, and cap it to obtain a sodium aescinate liposome freeze-dried powder injection.

[0095] The encapsulation efficiency was measured to be 97.05%, the particle size was 110.1 nm, and the PDI was 0.102.

[0096] Example 8: Preparation of sodium aescinate liposomes

[0097] Weigh 3g of high-purity egg yolk phosphatidylcholine (EPCS), 1.5g of cholesterol, and 0.1g of DSPE-PEG20000 in the prescribed amount, place them in 11.00g of anhydrous ethanol, and heat them at 65°C to dissolve them to obtain an organic phase; weigh 0.20g of sodium aescinate in the prescribed amount and dissolve them in 84g of water for injection, adjust the pH value to 3.35 with citric acid, and keep warm at 55°C to obtain an aqueous phase; inject the organic phase into the aqueous phase under stirring conditions, mix well, The volume was made up to 100 mL with water for injection to obtain crude liposomes; the crude liposomes were extruded through a 0.2 μm extrusion membrane for 2 times, and then through a 0.1 μm extrusion membrane for 5 times to obtain a liposome solution; an equal amount of water for injection was added and ultrafiltered for 5 times to remove the organic solvent; 10.00 g of sucrose was weighed and placed in the above liposome solution, stirred to dissolve, sterilized through a 0.22 μm filter membrane, packaged, freeze-dried, and capped to obtain sodium aescinate liposome freeze-dried powder injection.

[0098] It was determined that the encapsulation efficiency was 95.71%, the particle size was 108.4 nm, and the PDI was 0.104.

[0099] Example 9: Preparation of sodium aescinate liposomes

[0100] Weigh 3 g of high-purity egg yolk phosphatidylcholine (EPCS), 1.5 g of cholesterol, and 0.1 g of DSPE-PEG20000 in the prescribed amount, place them in 10.00 g of anhydrous ethanol, and heat them at 55°C to dissolve them to obtain an organic phase; weigh 0.25 g of sodium aescinate in the prescribed amount and dissolve them in 82 g of water for injection, adjust the pH value to 2.0 with citric acid, and keep warm at 55°C to obtain an aqueous phase; inject the organic phase into the aqueous phase under stirring, mix well, and dilute to 1% with water for injection. 00mL to obtain crude liposomes; the crude liposomes were homogenized 3 times by a high-pressure homogenizer at 10000psi, 15000psi and 20000psi respectively to obtain a liposome solution; an equal amount of water for injection after adjusting the pH was added and ultrafiltered 4 times to remove the organic solvent; 8g of sucrose was weighed and placed in the above liposome solution, stirred to dissolve, sterilized through a 0.22μm filter membrane, packaged, freeze-dried, and capped to obtain sodium aescinate liposome freeze-dried powder injection.

[0101] It was determined that the encapsulation efficiency was 95.84%, the particle size was 167.3 nm, and the PDI was 0.192.

[0102] Example 10: Preparation of sodium aescinate liposomes

[0103] Weigh 3g of high-purity egg yolk phosphatidylcholine (EPCS), 1.5g of cholesterol, and 0.1g of DSPE-PEG20000 in the prescribed amount, place them in 13.00g of anhydrous ethanol, and heat them at 60°C to dissolve them to obtain an organic phase; weigh 0.25g of sodium aescinate in the prescribed amount, dissolve them in 80g of water for injection, adjust the pH value to 3.5 with citric acid, and keep them warm at 60°C to obtain an aqueous phase; inject the organic phase into the aqueous phase under stirring, mix well, and dilute to 100mL with water for injection to obtain a crude liposome; extrude the crude liposome through a 0.2μm extrusion membrane for 2 times, and then extrude it through a 0.1μm extrusion membrane for 5 times to obtain a liposome solution; add an equal amount of water for injection and ultrafilter for 5 times to remove the organic solvent; weigh 15.00g of sucrose, place it in the above liposome solution, stir to dissolve it, sterilize it through a 0.22μm filter membrane, divide it into portions, freeze-dry it, and cap it to obtain a sodium aescinate liposome freeze-dried powder injection.

[0104] It was determined that the encapsulation efficiency was 92.07%, the particle size was 116.2 nm, and the PDI was 0.116.

[0105] Example 11: Preparation of sodium aescinate liposomes

[0106] Weigh 5 g of high-purity egg yolk phosphatidylcholine (EPCS), 2.5 g of cholesterol, and 0.3 g of DSPE-PEG20000 in the prescribed amount, place them in 13.00 g of anhydrous ethanol, and heat them at 50°C to dissolve them to obtain an organic phase; weigh 0.3 g of sodium aescinate in the prescribed amount and dissolve them in 76 g of water for injection, adjust the pH value to 3.5 with citric acid, and keep warm at 55°C to obtain an aqueous phase; inject the organic phase into the aqueous phase under stirring, mix well, and dilute to 1% with water for injection. 00mL to obtain crude liposomes; the crude liposomes were homogenized 3 times by a high-pressure homogenizer at 10000psi, 15000psi and 20000psi respectively to obtain a liposome solution; an equal amount of water for injection after adjusting the pH was added and ultrafiltered 6 times to remove the organic solvent; 11.00g of sucrose was weighed and placed in the above liposome solution, stirred to dissolve, sterilized through a 0.22μm filter membrane, packaged, freeze-dried, and capped to obtain sodium aescinate liposome freeze-dried powder injection.

[0107] It was determined that the encapsulation efficiency was 93.11%, the particle size was 127.9 nm, and the PDI was 0.188.

[0108] Example 12: Preparation of sodium aescinate liposomes

[0109] Weigh 4.0 g of high-purity egg yolk phosphatidylcholine (EPCS), 1.0 g of cholesterol, and 0.1 g of DSPE-PEG20000 in the prescribed amount, place them in 12 g of anhydrous ethanol, and heat them at 60°C to dissolve them to obtain an organic phase; weigh 0.25 g of sodium aescinate in the prescribed amount and dissolve them in 81 g of water for injection, adjust the pH value to 2.5 with citric acid, and keep warm at 60°C to obtain an aqueous phase; inject the organic phase into the aqueous phase under stirring, mix well, and use an injection The volume was adjusted to 100 mL with water to obtain crude liposomes; the crude liposomes were extruded through a 0.2 μm extrusion membrane for 2 times, and then through a 0.1 μm extrusion membrane for 5 times to obtain a liposome solution; an equal amount of water for injection after adjusting the pH was added, and ultrafiltration was performed for 5 times to remove the organic solvent; 25 g of trehalose was weighed, placed in the above liposome solution, stirred to dissolve, sterilized through a 0.22 μm filter membrane, divided, freeze-dried, and capped to obtain sodium aescinate liposome freeze-dried powder injection.

[0110] It was determined that the encapsulation efficiency was 90.67%, the particle size was 109.1 nm, and the PDI was 0.186.

[0111] Example 13: Preparation of sodium aescinate liposomes

[0112] Weigh the prescribed amount of high-purity egg yolk phosphatidylcholine (EPCS) 1.64g, cholesterol 1.36g, DSPE-PEG2000 0.01g was placed in 11.00g of anhydrous ethanol, heated at 65°C to dissolve, and an organic phase was obtained; 0.2g of the prescribed amount of sodium aescinate was weighed and dissolved in 78g of water for injection, the pH value was adjusted to 3.38 with citric acid, and the mixture was kept warm at 55°C to obtain an aqueous phase; the organic phase was injected into the aqueous phase under stirring, mixed, and the volume was adjusted to 100mL with water for injection to obtain a crude liposome; the crude liposome was passed through a high-pressure homogenizer, and homogenized 3 times at 10000psi, 15000psi and 20000psi respectively to obtain a liposome solution; an equal amount of water for injection after adjusting the pH was added, and ultrafiltration was performed 5 times to remove the organic solvent; 8g of sucrose was weighed and placed in the above liposome solution, stirred to dissolve, sterilized through a 0.22μm filter membrane, packaged, freeze-dried, and capped to obtain a sodium aescinate liposome freeze-dried powder injection.

[0113] It was determined that the encapsulation efficiency was 94.31%, the particle size was 103.9 nm, and the PDI was 0.111.

[0114] Example 14: Preparation of sodium aescinate liposomes

[0115] Weigh 3g of high-purity egg yolk phosphatidylcholine (EPCS), 1.5g of cholesterol, and 0.1g of DSPE-PEG20000 in the prescribed amount, place them in 11.00g of propylene glycol, and heat them at 50°C to dissolve them to obtain an organic phase; weigh 0.25g of sodium aescinate in the prescribed amount, dissolve them in 83g of water for injection, adjust the pH value to 4.8 with hydrochloric acid, and keep them warm at 50°C to obtain an aqueous phase; inject the organic phase into the aqueous phase under stirring, mix well, and dilute to 100mL with water for injection to obtain a crude liposome; extrude the crude liposome through a 0.2μm extrusion membrane for 2 times, and then extrude it through a 0.1μm extrusion membrane for 5 times to obtain a liposome solution; add an equal amount of water for injection and ultrafilter for 4 times to remove the organic solvent; weigh 15.00g of maltose, place it in the above liposome solution, stir to dissolve it, sterilize it through a 0.22μm filter membrane, divide it into portions, freeze-dry it, and cap it to obtain a sodium aescinate liposome freeze-dried powder injection.

[0116] It was determined that the encapsulation efficiency was 90.27%, the particle size was 123.5 nm, and the PDI was 0.168.

[0117] Example 15: Preparation of sodium aescinate liposomes

[0118] Weigh 3 g of high-purity egg yolk phosphatidylcholine (EPCS), 1.5 g of cholesterol, and 0.1 g of DSPE-PEG20000 in the prescribed amount, place them in 11.00 g of anhydrous ethanol, and heat them at 55°C to dissolve them to obtain an organic phase; weigh 0.25 g of sodium aescinate in the prescribed amount and dissolve them in 86 g of water for injection, adjust the pH value to 2.5 with citric acid, and keep warm at 55°C to obtain an aqueous phase; inject the organic phase into the aqueous phase under stirring, mix well, and use an injection The volume was made up to 100 mL with water to obtain crude liposomes; the crude liposomes were homogenized 3 times at 12000 psi, 18000 psi and 22000 psi by a high-pressure homogenizer to obtain a liposome solution; an equal amount of water for injection was added and ultrafiltered 4 times to remove the organic solvent; 5 g of sucrose was weighed and placed in the above liposome solution, stirred to dissolve, sterilized by filtering through a 0.22 μm filter membrane, packaged, freeze-dried and capped to obtain sodium aescinate liposome freeze-dried powder injection.

[0119] It was determined that the encapsulation efficiency was 97.48%, the particle size was 163.2 nm, and the PDI was 0.194.

[0120] Example 16: Preparation of sodium aescinate liposomes

[0121] Weigh 3g of high-purity egg yolk phosphatidylcholine (EPCS), 1.5g of cholesterol, and 0.1g of DSPE-PEG20000 in the prescribed amount, place them in 11.00g of anhydrous ethanol, and heat them at 55°C to dissolve them to obtain an organic phase; weigh 0.25g of sodium aescinate in the prescribed amount, dissolve them in 82g of water for injection, adjust the pH value to 3.5 with citric acid, and keep them warm at 55°C to obtain an aqueous phase; inject the organic phase into the aqueous phase under stirring conditions, mix well, and dilute to 100mL with water for injection to obtain a crude liposome; pass the crude liposome through probe ultrasound (working for 30s, stopping for 10s, for a total of 8 cycles) to obtain a liposome solution; add an equal amount of water for injection after adjusting the pH, and ultrafilter 5 times to remove the organic solvent; weigh 20g of sucrose, place it in the above liposome solution, stir to dissolve it, sterilize it through a 0.22μm filter membrane, divide it into portions, freeze-dry it, and cap it to obtain a sodium aescinate liposome freeze-dried powder injection.

[0122] It was determined that the encapsulation efficiency was 95.05%, the particle size was 197.4 nm, and the PDI was 0.233.

[0123] Example 17: Preparation of sodium aescinate liposomes

[0124] Weigh 3g of high-purity egg yolk phosphatidylcholine (EPCS), 1.5g of cholesterol, and 0.1g of DSPE-PEG2000 in the prescribed amount, place them in 9g of anhydrous ethanol, and heat them at 55°C to dissolve them to obtain an organic phase; weigh 0.20g of sodium aescinate in the prescribed amount, dissolve them in 84g of water for injection, adjust the pH value to 3.5 with citric acid, and keep them warm at 55°C to obtain an aqueous phase; inject the organic phase into the aqueous phase under stirring conditions, mix well, and dilute to 100mL with water for injection to obtain a crude liposome; extrude the crude liposome through a 0.2μm extrusion membrane for 2 times, and then extrude it through a 0.1μm extrusion membrane for 5 times to obtain a liposome solution; add an equal amount of water for injection after adjusting the pH, and ultrafilter 3 times to remove the organic solvent; weigh 12g of sucrose, place it in the above liposome solution, stir to dissolve it, sterilize it through a 0.22μm filter membrane, divide it into portions, freeze-dry it, and cap it to obtain a sodium aescinate liposome freeze-dried powder injection.

[0125] The encapsulation efficiency was measured to be 97.11%, the particle size was 125.1 nm, and the PDI was 0.154.

[0126] Example 18: Preparation of sodium aescinate liposomes

[0127] Weigh 3g of high-purity egg yolk phosphatidylcholine (EPCS), 1.0g of cholesterol, and 0.1g of DSPE-PEG20000 in the prescribed amount, place them in 11.00g of anhydrous ethanol, and heat them at 55°C to dissolve them to obtain an organic phase; weigh 0.25g of sodium aescinate in the prescribed amount, dissolve them in 82g of water for injection, adjust the pH value to 3.5 with citric acid, and keep them warm at 55°C to obtain an aqueous phase; inject the organic phase into the aqueous phase under stirring, mix well, and dilute to 100mL with water for injection to obtain a crude liposome; extrude the crude liposome through a 0.2μm extrusion membrane for 2 times, and then extrude it through a 0.1μm extrusion membrane for 5 times to obtain a liposome solution; add an equal amount of water for injection and ultrafilter for 4 times to remove the organic solvent; weigh 20g of sucrose, place it in the above liposome solution, stir to dissolve it, sterilize it through a 0.22μm filter membrane, divide it into portions, freeze-dry it, and cap it to obtain a sodium aescinate liposome freeze-dried powder injection.

[0128] It was determined that the encapsulation efficiency was 92.34%, the particle size was 107.3 nm, and the PDI was 0.126.

[0129] Example 19: Preparation of sodium aescinate liposomes

[0130] Weigh 5 g of high-purity egg yolk phosphatidylcholine (EPCS), 2.5 g of cholesterol, and 0.3 g of DSPE-PEG20000 in the prescribed amount, place them in 15.00 g of propylene glycol, and heat them at 65° C. to dissolve them to obtain an organic phase; weigh 0.25 g of sodium aescinate in the prescribed amount, dissolve them in 74 g of water for injection, adjust the pH value to 3.5 with citric acid, and keep them warm at 55° C. to obtain an aqueous phase; inject the aqueous phase into the organic phase under stirring, mix well, and dilute to 100 mL with water for injection to obtain a crude liposome; extrude the crude liposome through a 0.2 μm extrusion membrane for 2 times, and then extrude it through a 0.1 μm extrusion membrane for 5 times to obtain a liposome solution; add an equal amount of water for injection and ultrafilter for 6 times to remove the organic solvent; weigh 8 g of sucrose, place it in the above liposome solution, stir to dissolve it, sterilize it through a 0.22 μm filter membrane, dispense, freeze-dry, and cap to obtain a sodium aescinate liposome freeze-dried powder injection.

[0131] It was determined that the encapsulation efficiency was 92.42%, the particle size was 128.1 nm, and the PDI was 0.178.

[0132] Example 20: Preparation of sodium aescinate liposomes

[0133] Weigh 5 g of high-purity egg yolk phosphatidylcholine (EPCS), 1 g of cholesterol, and 0.1 g of DSPE-PEG20000 in the prescribed amount, place them in 13.00 g of tert-butanol, and heat at 55°C to dissolve them to obtain an organic phase; weigh 0.20 g of sodium aescinate in the prescribed amount and dissolve them in 78 g of water for injection, adjust the pH value to 2.5 with citric acid, and keep warm at 55°C to obtain an aqueous phase; inject the aqueous phase into the organic phase under stirring, mix well, and dilute to 100 mL with water for injection to obtain a crude liposome; extrude the crude liposome through 0.8 μm for 2 times and then through 0.4 μm for 5 times to obtain a liposome solution; sterilize through a 0.22 μm filter membrane, subpackage, freeze-dry, and cap to obtain sodium aescinate liposome freeze-dried powder injection.

[0134] It was determined that the encapsulation efficiency was 90.53%, the particle size was 177.3 nm, and the PDI was 0.154.

[0135] Example 21: Preparation of sodium aescinate liposomes

[0136] Weigh 1g of high-purity egg yolk phosphatidylcholine (EPCS), 0.5g of cholesterol, and 0.1g of DSPE-PEG20000 in the prescribed amount, place them in 7g of anhydrous ethanol, and heat at 55°C to dissolve them to obtain an organic phase; weigh 0.3g of sodium aescinate in the prescribed amount, dissolve it in 90g of water for injection, adjust the pH value to 3.5 with hydrochloric acid, and keep it warm at 55°C to obtain an aqueous phase; inject the organic phase into the aqueous phase under stirring, mix well, and dilute to 100mL with water for injection to obtain a crude liposome; extrude the crude liposome through a 0.2μm extrusion membrane for 2 times, and then extrude it through a 0.1μm extrusion membrane for 5 times to obtain a liposome solution; add an equal amount of water for injection with corresponding pH adjustment and ultrafilter 3 times to remove the organic solvent; weigh 7g of sucrose, place it in the above liposome solution, stir to dissolve it, sterilize it through a 0.22μm filter membrane, divide it into portions, freeze-dry it, and cap it to obtain a sodium aescinate liposome freeze-dried powder injection.

[0137] It was determined that the encapsulation efficiency was 93.57%, the particle size was 121.13 nm, and the PDI was 0.136.

[0138] Example 22: Preparation of sodium aescinate liposomes

[0139] Weigh 3g of high-purity egg yolk phosphatidylcholine (EPCS), 1.5g of cholesterol, and 0.1g of DSPE-PEG20000 in the prescribed amount, place them in 15.00g of anhydrous ethanol, and heat them at 55°C to dissolve them to obtain an organic phase; weigh 0.25g of sodium aescinate in the prescribed amount, dissolve them in 78g of water for injection, adjust the pH value to 3.5 with hydrochloric acid, and keep warm at 55°C to obtain an aqueous phase; inject the organic phase into the aqueous phase under stirring, mix well, and dilute to 100mL with water for injection to obtain a crude liposome; extrude the crude liposome through a 0.2μm extrusion membrane for 2 times, and then extrude it through a 0.1μm extrusion membrane for 5 times to obtain a liposome solution; add an equal amount of water for injection and ultrafilter for 7 times to remove the organic solvent; weigh 25g of sucrose, place it in the above liposome solution, stir to dissolve it, sterilize it through a 0.22μm filter membrane, divide it into portions, freeze-dry it, and cap it to obtain a sodium aescinate liposome freeze-dried powder injection.

[0140] It was determined that the encapsulation efficiency was 90.91%, the particle size was 113.2 nm, and the PDI was 0.118.

[0141] Example 23: Preparation of sodium aescinate liposomes

[0142] Weigh 3g of high-purity egg yolk phosphatidylcholine (EPCS), 1.5g of cholesterol, and 0.2g of DSPE-PEG20000 in the prescribed amount, place them in 11.00g of anhydrous ethanol, and heat them at 60°C to dissolve them to obtain an organic phase; weigh 0.25g of sodium aescinate in the prescribed amount, dissolve them in 82g of water for injection, adjust the pH value to 4.8 with citric acid, and keep them warm at 60°C to obtain an aqueous phase; inject the organic phase into the aqueous phase under stirring conditions, mix well, and dilute to 100mL with water for injection to obtain a crude liposome; extrude the crude liposome through a 0.2μm extrusion membrane for 2 times, and then extrude it through a 0.1μm extrusion membrane for 5 times to obtain a liposome solution; add an equal amount of water for injection and ultrafilter for 4 times to remove the organic solvent; weigh 12g of trehalose, place it in the above liposome solution, stir to dissolve it, sterilize it through a 0.22μm filter membrane, divide it into portions, freeze-dry it, and cap it to obtain a sodium aescinate liposome freeze-dried powder injection.

[0143] It was determined that the encapsulation efficiency was 90.27%, the particle size was 115.6 nm, and the PDI was 0.121.

[0144] Example 24: Preparation of sodium aescinate liposomes

[0145] Weigh 3g of distearoylphosphatidylcholine (DSPC), 1.5g of cholesterol, and 0.1g of DSPE-PEG2000 in the prescribed amount, place them in 14g of anhydrous ethanol, and heat them at 65°C to dissolve them to obtain an organic phase; weigh 0.2g of sodium aescinate in the prescribed amount and dissolve them in 78g of water for injection, adjust the pH value to 4.8 with citric acid, and heat them to 65°C to obtain an aqueous phase; inject the organic phase into the aqueous phase under stirring conditions and mix them well to obtain a crude liposome; extrude the crude liposome through a 0.2μm extrusion membrane for 2 times, and then extrude it through a 0.1μm extrusion membrane for 6 times to obtain a liposome solution; add an equal amount of water for injection and ultrafilter for 6 times to remove the organic solvent; weigh 20g of maltose, place it in the above liposome solution, stir to dissolve it, dilute to 100mL with water for injection, sterilize through a 0.22μm filter membrane, dispense, freeze-dry, and cap to obtain sodium aescinate liposome freeze-dried powder injection.

[0146] It was determined that the encapsulation efficiency was 90.58%, the particle size was 196.4 nm, and the PDI was 0.266.

[0147] Example 25: Preparation of sodium aescinate liposomes

[0148] Weigh 3g of hydrogenated soybean lecithin (HSPC), 1.5g of cholesterol, and 0.1g of DSPE-PEG20000 in the prescribed amount, place them in 13.00g of anhydrous ethanol, and heat them at 55°C to dissolve them to obtain an organic phase; weigh 0.2g of sodium aescinate in the prescribed amount and dissolve them in 78g of water for injection, adjust the pH value to 4.8 with citric acid, and heat them to 55°C to obtain an aqueous phase; inject the organic phase into the aqueous phase under stirring conditions and mix them well to obtain a crude liposome; extrude the crude liposome through a 0.2μm extrusion membrane for 2 times, and then extrude it through a 0.1μm extrusion membrane for 5 times to obtain a liposome solution; add an equal amount of water for injection and ultrafilter for 6 times to remove the organic solvent; weigh 10.00g of maltose, place it in the above liposome solution, stir to dissolve it, dilute to 100mL with water for injection, sterilize through a 0.22μm filter membrane, dispense, freeze-dry, and cap to obtain sodium aescinate liposome freeze-dried powder injection.

[0149] It was determined that the encapsulation efficiency was 91.27%, the particle size was 164.2 nm, and the PDI was 0.151.

[0150] Example 26: Preparation of sodium aescinate liposomes

[0151] Weigh 1g of high-purity egg yolk phosphatidylcholine (EPCS), 0.5g of cholesterol, and 20000g of DSPE-PEG in the prescribed amount, place them in 10.00g of anhydrous ethanol, and heat them at 55°C to dissolve them to obtain an organic phase; weigh 0.10.00g of sodium aescinate in the prescribed amount, dissolve them in 86g of water for injection, adjust the pH value to 3.5 with hydrochloric acid, and keep warm at 55°C to obtain an aqueous phase; inject the organic phase into the aqueous phase under stirring, mix well, and dilute to 100mL with water for injection to obtain a crude liposome; extrude the crude liposome through a 0.1μm extrusion membrane twice, and then extrude it through a 0.05μm extrusion membrane 4 times to obtain a liposome solution; add an equal amount of water for injection and ultrafilter 4 times to remove the organic solvent; weigh 12g of trehalose, place it in the above liposome solution, stir to dissolve it, sterilize it through a 0.22μm filter membrane, divide it into portions, freeze-dry it, and cap it to obtain a sodium aescinate liposome freeze-dried powder injection.

[0152] It was determined that the encapsulation efficiency was 91.03%, the particle size was 78.72 nm, and the PDI was 0.145.

[0153] Example 27: Preparation of sodium aescinate liposomes

[0154] Weigh 10.00 g of high-purity egg yolk phosphatidylcholine (EPCS), 5 g of cholesterol, and 1 g of DSPE-PEG2000 in the prescribed amount, place them in 12 g of anhydrous ethanol, and heat them at 60°C to dissolve them to obtain an organic phase; weigh 0.50 g of sodium aescinate in the prescribed amount, dissolve them in 70 g of water for injection, adjust the pH value to 3.4 with hydrochloric acid, and keep them warm at 60°C to obtain an aqueous phase; inject the organic phase into the aqueous phase under stirring conditions, mix well, and dilute to 100 mL with water for injection to obtain a crude liposome; extrude the crude liposome through a 0.2 μm extrusion membrane for 3 times, and then extrude it through a 0.1 μm extrusion membrane for 6 times to obtain a liposome solution; add an equal amount of water for injection after adjusting the pH, and ultrafilter 5 times to remove the organic solvent; weigh 12 g of sucrose, place it in the above liposome solution, stir to dissolve it, sterilize it through a 0.22 μm filter membrane, divide it into portions, freeze-dry it, and cap it to obtain a sodium aescinate liposome freeze-dried powder injection.

[0155] It was determined that the encapsulation efficiency was 95.43%, the particle size was 147.4 nm, and the PDI was 0.122.

[0156] Example 28: Preparation of sodium aescinate liposomes

[0157] Weigh the prescribed amount of high-purity egg yolk phosphatidylcholine (EPCS) 1.33g, cholesterol 0.67g, DSPE-PEG2000 0.01g, placed in 7g of anhydrous ethanol, heated at 50℃ to dissolve, to obtain an organic phase; weighed 0.20g of the prescribed amount of sodium aescinate, dissolved in 88g of water for injection, adjusted the pH value to 3.4 with hydrochloric acid, and kept warm at 50℃ to obtain an aqueous phase; injected the organic phase into the aqueous phase under stirring, mixed, and diluted to 100mL with water for injection to obtain a crude liposome; extruded the crude liposome through a 0.1μm extrusion membrane for 2 times, and then through a 0.08μm extrusion for 5 times to obtain a liposome solution; added an equal amount of water for injection after adjusting the pH, and ultrafiltered 3 times to remove the organic solvent; weighed 12g of sucrose, placed in the above liposome solution, stirred to dissolve, sterilized through a 0.22μm filter membrane, packaged, freeze-dried, and capped to obtain sodium aescinate liposome freeze-dried powder injection.

[0158] It was determined that the encapsulation efficiency was 94.89%, the particle size was 95.51 nm, and the PDI was 0.188.

[0159] Example 29: Preparation of sodium aescinate liposomes

[0160] Weigh the prescribed amount of high-purity egg yolk lecithin (PL-100M) 1.2g, cholesterol 1g, DSPE-PEG2000 0.2g of sodium aescinate was placed in 11.00g of anhydrous ethanol, heated at 50°C to dissolve, and an organic phase was obtained; 0.25g of the prescribed amount of sodium aescinate was weighed and dissolved in 84g of water for injection, the pH value was adjusted to 3.37 with hydrochloric acid, and kept warm at 55°C to obtain an aqueous phase; the organic phase was injected into the aqueous phase under stirring, mixed, and the volume was adjusted to 100mL with water for injection to obtain a crude liposome; the crude liposome was extruded through a 0.2μm extrusion membrane for 2 times, and then through a 0.1μm extrusion membrane for 5 times to obtain a liposome solution; an equal amount of water for injection was added and ultrafiltered 4 times to remove the organic solvent; 12g of sucrose was weighed and placed in the above liposome solution, stirred to dissolve, sterilized through a 0.22μm filter membrane, packaged, freeze-dried, and capped to obtain sodium aescinate liposome freeze-dried powder injection.

[0161] It was determined that the encapsulation efficiency was 92.11%, the particle size was 117.0 nm, and the PDI was 0.168.

[0162] Example 30: Preparation of sodium aescinate liposomes

[0163] Weigh 2g of high-purity egg yolk phosphatidylcholine (EPCS), 2g of cholesterol, and 0.05g of DSPE-PEG2000 in the prescribed amount, place them in 10.00g of tert-butanol, and heat at 55°C to dissolve them to obtain an organic phase; weigh 0.30g of sodium aescinate in the prescribed amount and dissolve them in 83g of water for injection, adjust the pH value to 3.4 with hydrochloric acid, and keep warm at 55°C to obtain an aqueous phase; inject the organic phase into the aqueous phase under stirring, mix well, and dilute to 100mL with water for injection to obtain a crude liposome; extrude the crude liposome through 0.6μm for 2 times and then through 0.08μm for 5 times to obtain a liposome solution; sterilize through a 0.22μm filter membrane, subpackage, freeze-dry, and cap to obtain sodium aescinate liposome freeze-dried powder injection.

[0164] It was determined that the encapsulation efficiency was 93.47%, the particle size was 86.00 nm, and the PDI was 0.104.

[0165] Example 31: Preparation of sodium aescinate liposomes

[0166] Weigh 7g of high-purity egg yolk phosphatidylcholine (EPCS), 3g of cholesterol, and 0.3g of DSPE-PEG2000 in the prescribed amount, place them in 11.00g of propylene glycol, and heat them at 55°C to dissolve them to obtain an organic phase; weigh 0.4g of sodium aescinate in the prescribed amount, dissolve them in 74g of water for injection, adjust the pH value to 4.5 with hydrochloric acid, and keep them warm at 55°C to obtain an aqueous phase; inject the organic phase into the aqueous phase under stirring conditions, mix well, and dilute to 100mL with water for injection to obtain a crude liposome; extrude the crude liposome through a 0.2μm extrusion membrane for 2 times, and then extrude it through a 0.1μm extrusion membrane for 6 times to obtain a liposome solution; add an equal amount of water for injection after adjusting the pH, and ultrafilter 6 times to remove the organic solvent; weigh 12g of sucrose, place it in the above liposome solution, stir to dissolve it, sterilize it through a 0.22μm filter membrane, divide it into portions, freeze-dry it, and cap it to obtain a sodium aescinate liposome freeze-dried powder injection.

[0167] It was determined that the encapsulation efficiency was 90.65%, the particle size was 115.7 nm, and the PDI was 0.128.

[0168] Example 32: Preparation of sodium aescinate liposomes

[0169] Weigh 3 g of high-purity egg yolk phosphatidylcholine (EPCS), 1.5 g of cholesterol, and 0.05 g of DSPE-PEG20000 in the prescribed amount, place in 11.00 g of anhydrous ethanol, and heat at 55°C to dissolve to obtain an organic phase; weigh 0.25 g of sodium aescinate in the prescribed amount and dissolve in 82 g of water for injection, adjust the pH value to 2.7 with citric acid, and keep warm at 55°C to obtain an aqueous phase; inject the organic phase into the aqueous phase under stirring, mix well, The volume was made up to 100 mL with water for injection to obtain crude liposomes; the crude liposomes were extruded through a 0.2 μm extrusion membrane for 2 times, and then through a 0.1 μm extrusion membrane for 5 times to obtain a liposome solution; an equal amount of water for injection was added and ultrafiltered for 5 times to remove the organic solvent; 15.00 g of sucrose was weighed and placed in the above liposome solution, stirred to dissolve, sterilized through a 0.22 μm filter membrane, packaged, freeze-dried, and capped to obtain sodium aescinate liposome freeze-dried powder injection.

[0170] It was determined that the encapsulation efficiency was 96.19%, the particle size was 95.65.1nm, and the PDI was 0.135.

[0171] Example 33: Pharmacodynamic study of sodium aescinate liposomes for injection prepared in Examples 6, 7, and 15

[0172] 1. Mouse ear swelling model

[0173] 40 ICR mice were randomly divided into 5 groups (n=8), namely, a blank group, a sodium aescinate injection group (3.6 mg / kg) and aescinate injection liposome dosage group (Examples 6, 7, 15). Tail vein administration was continued for three consecutive days. 30 minutes after the last administration, 30 μL of xylene was applied to both sides of the right ear of each mouse to cause inflammation, and the left ear was not applied as a control. After 30 minutes of inflammation, the mice were killed, and the left and right ears were cut along the auricle baseline. The ear pieces were punched out at the same position with a 7.5 mm diameter puncher, and weighed with an analytical balance. The difference in weight (mg) of the left and right ear pieces was used to represent the degree of inflammatory swelling, and the swelling inhibition rate was calculated.

[0174]

[0175] Table 10 Ear swelling of mice in each group (x±s)

[0176] Group Dosage (mg / kg) Ear swelling (mg) Swelling inhibition rate (%) Model Group - 0.0078±0.0029 / Sodium aescinate injection group 3.6 0.0045±0.0012 42.31 Example 6 3.6 0.0021±0.0011 73.18** Example 7 3.6 0.0023±0.0010 70.51** Embodiment 15 3.6 0.0024±0.0013 69.23**

[0177] Note: *P<0.05, **P<0.01 compared with the control group.

[0178] 2. Rat cotton ball granuloma model

[0179] 40 SD rats were randomly divided into 5 groups, 8 rats in each group, namely, blank group, sodium aescinate injection group (1.8 mg / kg) and sodium aescinate injection liposome dosage group (Examples 6, 7, 15). 35 mg sterile cotton balls were implanted in the groin of each rat one day before the first administration, and the administration was continued for 7 days. 24 hours after the last administration, the cotton balls were taken out together with the surrounding connective tissue, the adipose tissue was removed, and the rats were placed in a 60°C drying oven for drying for 12 hours and weighed. The dry weight of the granulation tissue was obtained by subtracting the weight of the cotton balls from the weighed weight.

[0180] Table 11 Granuloma situation of rats in each group (x±s)

[0181] Group Dosage (mg / kg) Granuloma weight (mg) Inhibition rate (%) Model Group - 0.0863±0.0093 / Sodium aescinate injection group 1.8 0.0586±0.0094 32.10％** Example 6 1.8 0.0420±0.0078 51.33％**，## Example 7 1.8 0.0445±0.0153 48.44％**，# Embodiment 15 1.8 0.0461±0.0122 46.58％**，#

[0182] Note: Compared with the control group **P<0.01, compared with the model group # P<0.05, ## P<0.01.

[0183] Analysis of results: The sodium aescinate liposomes for injection prepared by the methods of the three embodiments were selected to conduct pharmacodynamic evaluation on the mouse ear swelling and rat cotton ball granuloma models together with sodium aescinate for injection. The experimental results showed that the therapeutic effects of the sodium aescinate liposomes for injection prepared by the three randomly selected embodiments were significantly better than those of sodium aescinate for injection, indicating that the overall therapeutic effect of the liposomes prepared by the present invention was greatly improved.

[0184] Example 34: Hemolytic evaluation of the sodium aescinate liposomes for injection prepared in Examples 6, 7, and 15

[0185] 1. Hemolytic Experiment Design

[0186] Hemolysis test is used to evaluate the safety of clinical use of sodium aescinate for injection. 20mL of blood is collected from the ear vein of a rabbit, and fibrinogen is removed with a glass rod to prepare defibrinated blood. Use 10 times the amount of normal saline, shake well, centrifuge at 2500r / min for 5min, and discard the supernatant. Wash the red blood cells precipitated in the lower layer with normal saline repeatedly 2 to 3 times according to the above method until the supernatant is colorless and transparent. Dilute the obtained red blood cells with normal saline by volume to a 2% red blood cell suspension.

[0187] Eight glass test tubes containing 2.5 mL of 2% red blood cell suspension were numerically marked. Different amounts of sodium aescinate liposomes for injection (0.5 mg / mL) (0.1, 0.2, 0.3, 0.4 and 0.5 mL) were added to test tubes 1-5. Test tube 6 contained only 2.5 mL of 0.9% saline as a negative control. Test tube 7 contained 2.5 mL of distilled water as a positive control. Test tube 8 contained 0.5 mL of sodium aescinate for injection (0.5 mg / mL) as a reference control. Physiological saline solution was added to 5 mL in each tube. After mixing, incubate at 37°C and observe at 15 min, 30 min, 45 min, 1 h, 2 h, 3 h and 4 h.

[0188] 2. Comparison of hemolytic properties between different examples and sodium aescinate for injection

[0189] Result analysis: Figure 1 As shown, the three selected examples did not have hemolysis, the red blood cells were deposited at the bottom of the test tube, and the supernatant was transparent, while tube 8 had hemolysis, the red blood cells ruptured, and the liquid was bright red. This further shows that the liposomes prepared by the present invention reduce the occurrence of hemolysis and are safer for clinical use.

[0190] Example 35: Irritation evaluation of the sodium aescinate liposomes for injection prepared in Examples 6, 7, and 15

[0191] 1. Stimulus program design

[0192] Fifteen rabbits (1.8-2.0 kg in weight) were randomly divided into five groups and injected with sodium aescinate liposomes and sodium aescinate for injection via the right ear vein of the rabbits, respectively, at a dose of 1.3 mg / kg and a push rate of 1 mL / min. At the same time, an equal volume of normal saline was given to the left ear via the ear vein as a control, and the drug was administered once a day for three consecutive days. The animal behavior and changes in the injection site were observed with the naked eye during the daily administration. Euthanasia was performed 24-48 hours after the last administration, and the ear vein tissues at about 0.5 cm-3.0 cm from the centripetal end of the injection site on both sides were obtained, fixed in 10% paraformaldehyde solution, dehydrated with ethanol gradient, embedded in paraffin, and stained with hematoxylin and ovoglobulin. All samples were examined using a BX43-DP21 light microscope (Olympus Co., Ltd., Japan), and pathological changes were evaluated.

[0193] 2. The results of the irritation evaluation are analyzed as follows:

[0194] like Figure 2 As shown, there was no obvious congestion in the ear veins of the rabbits in the blank group, the vascular wall structure was intact, and there was no obvious inflammatory lesions in the surrounding tissues. The stratified squamous epithelium on the surface of the auricle skin was intact, and there were no obvious lesions in the subcutaneous appendages such as hair follicles, sebaceous glands and sweat glands. The elastic cartilage in the central part was normal in morphology, there was no obvious lesion in the interstitial fibrous tissue of the auricle, and there was a small amount of chronic inflammatory cell infiltration in the interstitium.

[0195] In the sodium aescinate injection group, the auricular vein was congested and bleeding occurred, and the inflammatory cell infiltration around the wall of the vein was obvious. The subcutaneous connective tissue was loose and edematous, and the collagen fibers were broken; the interstitial fibrous tissue of the auricle appeared and many acute inflammatory cells infiltrated.

[0196] In the sodium aescinate liposome group (Examples 6, 7, and 15), the endothelial cells of the auricular vein were basically intact, with a small amount of inflammatory cell infiltration and a small amount of bleeding around the vascular wall. Fibrinous material was attached to the venous wall. No obvious degeneration, necrosis, hyperplasia and other lesions were found in the epidermal tissue of the skin. There were no obvious lesions in the deep skin appendages such as hair follicles, sebaceous glands and sweat gland tissues. The elastic cartilage in the central part had normal morphology, with normal chondrocytes, cartilage matrix and perichondrium structure.

[0197] Result analysis:

[0198] The sodium aescinate liposome for injection of the present invention has a high encapsulation rate, a small particle size, a narrow distribution, and smooth sterilization and filtration. More importantly, the sodium aescinate liposome for injection of the present invention can fundamentally solve the problems of strong hemolysis, strong irritation, and strong toxic and side effects of sodium aescinate.

[0199] The preferred embodiments of the present invention have been specifically described above, but the present invention is not limited to the embodiments. Those skilled in the art may make various equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. A sodium aescinate liposome, characterized in that: The invention uses sodium aescinate as an active ingredient and also includes lecithin, cholesterol and DSPE-PEG2000; wherein the amount of sodium aescinate is 0.1-0.5% w / v; the amount of lecithin is 2-7% w / v; the amount of cholesterol is 1-3% w / v; the amount of DSPE-PEG2000 is 0.01-0.3% w / v; the drug-lipid ratio is 1:10-1:30 g / g; the lecithin: cholesterol ratio is 1:1-5:1 g / g; when the sodium aescinate liposome is prepared, the prescribed amount of lecithin, cholesterol and DSPE-PEG2000 are placed in an organic solvent, heated and dissolved to obtain an organic phase; the organic solvent is selected from one or more of anhydrous ethanol, propylene glycol and tert-butyl alcohol, and the amount is 7-15% g / ml; the prescribed amount of sodium aescinate is dissolved in water for injection, and the pH value is adjusted to 2.0-4.8 with a pH regulator to obtain an aqueous phase.

2. The sodium aescinate liposome according to claim 1, characterized in that The sodium aescinate liposome is a freeze-dried powder injection.

3. The sodium aescinate liposome according to claim 2, characterized in that The sodium aescinate liposome is prepared by the following formula: Sodium aescinate 0.1-0.5% g / ml Lecithin 2-7% g / ml Cholesterol 1-3% g / ml DSPE-PEG2000 0.01-0.3% g / ml Lyoprotectant 5-25% g / ml pH adjuster adjusts pH to 2.0-4.8 Drug-lipid ratio 1:10-1:30 g / g Lecithin: Cholesterol 1:1-5:1 g / g Remaining amount of water for injection.

4. The sodium aescinate liposome according to claim 2, characterized in that The sodium aescinate liposome is prepared by the following formula: Sodium aescinate 0.2-0.4% g / ml Lecithin 2-7% g / ml Cholesterol 1-3% g / ml DSPE-PEG2000 0.01-0.3% g / ml Lyoprotectant 5-20% g / ml pH adjuster to adjust pH to 2.5-4.5 Drug-lipid ratio 1:10-1:20 g / g Lecithin: Cholesterol 1.2:1-4:1 g / g Remaining amount of water for injection.

5. The sodium aescinate liposome according to claim 1, characterized in that The lecithin is selected from one or more of egg yolk lecithin, hydrogenated soybean lecithin, distearoyl phosphatidylcholine, distearoyl phosphatidylglycerol, dipalmitoyl phosphatidylcholine, soybean lecithin, phosphatidylserine, dimyristoyl phosphatidylcholine, phosphatidylethanolamine and sphingomyelin.

6. The sodium aescinate liposome according to claim 1, characterized in that The lyophilization protective agent is selected from one or more of sucrose, trehalose, maltose, glucose, lactose, mannitol, sorbitol, xylitol, erythritol, and threonine; the pH adjusting agent is selected from one or more of citric acid, hydrochloric acid, sodium hydroxide, phosphoric acid, disodium hydrogen phosphate, disodium phosphate, dipotassium hydrogen phosphate, disodium citrate, and trisodium citrate.

7. A method for preparing sodium aescinate liposomes according to any one of claims 1 to 6, characterized in that: The following steps are involved: Weigh the prescribed amount of lecithin, cholesterol, and DSPE-PEG2000, place them in an organic solvent, and heat them at 50-65°C to dissolve them to obtain an organic phase; the organic solvent is selected from one or more of anhydrous ethanol, propylene glycol, and tert-butyl alcohol, and the amount is 7-15% g / ml; weigh the prescribed amount of sodium aescinate, dissolve it in an appropriate amount of water for injection, and heat it at 50-65°C to obtain an organic phase. Keep warm at ℃, adjust the pH value to 2.0-4.8 with a pH adjuster to obtain an aqueous phase; inject the organic phase into the aqueous phase under stirring conditions, mix well, and make up to the prescribed amount with water for injection to obtain a crude liposome; emulsify the crude liposome by using probe ultrasound, or place it in an extruder and extrude it through an extrusion membrane for several times, or place it in a high-pressure homogenizer for homogenization and emulsification to obtain a liposome solution; add an equal amount of water for injection or an equal amount of water for injection after adjusting the pH to ultrafilter several times to remove the organic solvent; weigh the prescribed amount of lyophilization protective agent, place it in the above liposome solution, stir to dissolve, sterilize through a 0.22 μm filter membrane, divide and package, lyophilize, and cap to obtain a sodium aescinate liposome lyophilized powder injection.

8. The method for preparing sodium aescinate liposomes according to claim 7, characterized in that: The crude liposome is emulsified, and the pore size of the extrusion membrane is selected from 0.8 μm, 0.6 μm, 0.4 μm, 0.2 μm, 0.1 μm, 0.08 μm, and 0.05 μm. One or more of them are selected to extrude multiple times through large pores to small pores in sequence.

9. Use of the sodium aescinate liposome according to any one of claims 1 to 6 in the preparation of anti-inflammatory drugs.

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