Application of asiatic acid-cyclodextrin inclusion compound eutectic in preparation of lung targeting preparation

Abstract

The invention relates to an application of an asiatic acid-cyclodextrin inclusion compound eutectic in preparation of a lung targeting preparation. In the research process, the inventor accidentally finds that the asiatic acid-cyclodextrin inclusion compound eutectic can be rapidly targeted to the lung through intravenous injection, a good lung targeting effect is achieved, and the medicine is effectively delivered to the lung. Meanwhile, the asiatic acid-cyclodextrin inclusion compound co-crystal is relatively good in water solubility, so that the medicine can be quickly dissolved out and released, and the treatment effect on lung diseases can be better realized.

Description

Technical Field

[0001] The present application relates to the field of pharmaceutical technology, and in particular to the use of an asiatic acid-cyclodextrin inclusion complex cocrystal in the preparation of a lung-targeted preparation. Background Art

[0002] Asiatic acid is a pentacyclic triterpene small molecule compound extracted from the whole herb of the Chinese medicinal material Centella asiatica, and its structure is shown in the following formula (1). Asiatic acid has multiple pharmacological activities, such as promoting wound healing, anti-inflammatory effects, antibacterial, antiviral, antioxidant, liver protection and anti-tumor biological effects.

[0003]

[0004] However, pentacyclic triterpenoid small molecule compounds generally have problems such as poor solubility, low oral bioavailability and severe first-pass effect, and Centella asiatica is no exception. There is a method that effectively improves the solubility and oral bioavailability of Centella asiatica by preparing inclusion cocrystals with Centella asiatica and cyclodextrin through the method of dissolution cooling crystallization. However, this method does not involve research related to the targeting effect of inclusion cocrystals. In addition, there are methods to increase the bioavailability of Centella asiatica through various nano-delivery technologies, but traditional nano-delivery systems are easily retained in the liver and kidneys, making it difficult to efficiently deliver to the lungs, and the nano-delivery system is prone to irreversible aggregation, which leads to vascular blockage. Summary of the invention

[0005] The present application provides the use of asiatic acid-cyclodextrin inclusion complex cocrystal in the preparation of lung-targeted preparations.

[0006] The specific technical solutions are as follows:

[0007] The present application provides the use of asiatic acid-cyclodextrin inclusion complex cocrystal in the preparation of lung-targeted preparations.

[0008] In one embodiment, the cyclodextrin is γ-cyclodextrin.

[0009] In one embodiment, the X-ray powder diffraction pattern of the asiatic acid-cyclodextrin inclusion complex cocrystal has characteristic diffraction peaks at the following 2θ (°) angles:

[0010] : 7.5°±0.2°, 9.2°±0.2°, 10.6°±0.2°, 11.8°±0.2°, 14.2°±0.2°, 14.9°±0.2°, 15.8°±0.2°, 16.7°±0.2°, 19.2°±0.2°, 20.3°±0.2°, 21.2°±0.2°, 21.8°±0.2°, 22.5°±0.2°, 23.7°±0.2° and 26.6°±0.2°.

[0011] In one embodiment, the X-ray powder diffraction pattern of the asiatic acid-cyclodextrin inclusion complex cocrystal is substantially as follows: Figure 4 shown.

[0012] In one of the embodiments, in the asiatic acid-cyclodextrin inclusion complex co-crystal, the mass percentage of asiatic acid is 10% to 12%.

[0013] In one of the embodiments, the particle size of the asiatic acid-cyclodextrin inclusion complex co-crystal is 1 μm to 3 μm.

[0014] In one embodiment, the hemolysis rate of the lung-targeted formulation is ≤5%.

[0015] In one embodiment, the lung-targeted formulation is an intravenous injection formulation.

[0016] In one embodiment, the lung-targeted formulation is a formulation for treating acute lung injury.

[0017] In one embodiment, the treatment of acute lung injury has at least one of the following characteristics (1) to (4):

[0018] (1) Decreased inflammatory cell infiltration in lung tissue;

[0019] (2) decreased pulmonary interstitial proliferation;

[0020] (3) reduction in pulmonary edema;

[0021] (4) Reduced pulmonary congestion.

[0022] The inventor accidentally discovered during the research that the asiatic acid-cyclodextrin inclusion compound cocrystal can be quickly targeted to the lungs through intravenous injection, play a good lung targeting role, and effectively deliver drugs to the lungs. At the same time, the asiatic acid-cyclodextrin inclusion compound cocrystal has good water solubility, quickly dissolves and releases drugs, and better achieves the therapeutic effect of lung diseases.

[0023] In addition, it was found during the research that the asiatic acid-cyclodextrin inclusion complex cocrystal has a low hemolysis rate, high safety, is not easy to aggregate, and reduces blood vessel blockage. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic diagram of the preparation process of the asiatic acid-cyclodextrin inclusion complex co-crystal provided as an example of the present application;

[0025] Figure 2 An optical microscope photograph of the asiatic acid-cyclodextrin inclusion complex co-crystal provided as an example of the present application (scale: 20 μm);

[0026] Figure 3The particle size distribution diagram of the Centella asiatica acid-cyclodextrin inclusion complex co-crystal provided as an example of the present application;

[0027] Figure 4 The XPRD spectra of Asiatic acid, γ-cyclodextrin and Asiatic acid-cyclodextrin inclusion complex cocrystal provided in an example of the present application (the abscissa is the angle 2θ (°), and the ordinate is the intensity);

[0028] Figure 5 This is a graph showing the hemolysis rate experimental results of the Centella asiatica acid-cyclodextrin inclusion complex co-crystal provided in an example of the present application;

[0029] Figure 6 This is a diagram showing the experimental results of the lung targeting effect of the Asiatic acid-cyclodextrin inclusion complex co-crystal provided in an example of the present application;

[0030] Figure 7 A schematic diagram of the experimental process of investigating an acute lung injury model in an example of this application;

[0031] Figure 8 This is a diagram of the acute lung injury treatment results of the Centella asiatica-cyclodextrin inclusion complex cocrystal provided as an example of the present application, wherein 1 indicates thickening of the pulmonary interstitium and macrophage infiltration at that location; 2 indicates congestion at that location; and 3 indicates edema at that location. DETAILED DESCRIPTION

[0032] The application of the asiatic acid-cyclodextrin inclusion complex cocrystal of the present application in the preparation of lung targeted preparations is further described in detail below in conjunction with specific examples. The present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present application more thorough and comprehensive.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0034] In the present application, the technical features described in an open manner include closed technical solutions composed of the listed features, and also include open technical solutions containing the listed features.

[0035] In this application, when it comes to numerical ranges, unless otherwise specified, the above numerical ranges are deemed to be continuous and include the minimum and maximum values ​​of the range, as well as each value between such minimum and maximum values. Further, when a range refers to an integer, each integer between the minimum and maximum values ​​of the range is included. In addition, when multiple ranges are provided to describe features or characteristics, the ranges can be merged. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges included therein.

[0036] The percentage contents involved in this application, unless otherwise specified, refer to mass percentage for solid-liquid mixing and solid-solid mixing, and refer to volume percentage for liquid-liquid mixing.

[0037] The percentage concentrations mentioned in this application, unless otherwise specified, refer to the final concentration, which refers to the percentage of the added component in the system after the addition of the component.

[0038] The temperature parameters in this application, unless otherwise specified, allow for both constant temperature treatment and treatment within a certain temperature range. The constant temperature treatment allows the temperature to fluctuate within the accuracy range of instrument control.

[0039] The room temperature in the present application generally refers to 4°C to 30°C, preferably 20±5°C.

[0040] Some examples of the present application provide the use of asiatic acid-cyclodextrin inclusion compound co-crystal in preparing lung-targeted preparations.

[0041] In some examples, the cyclodextrin is γ-cyclodextrin.

[0042] In some examples, the X-ray powder diffraction pattern of the asiatic acid-cyclodextrin inclusion complex co-crystal has characteristic diffraction peaks at the following 2θ (°) angles:

[0043] : 7.5°±0.2°, 9.2°±0.2°, 10.6°±0.2°, 11.8°±0.2°, 14.2°±0.2°, 14.9°±0.2°, 15.8°±0.2°, 16.7°±0.2°, 19.2°±0.2°, 20.3°±0.2°, 21.2°±0.2°, 21.8°±0.2°, 22.5°±0.2°, 23.7°±0.2° and 26.6°±0.2°.

[0044] In some of the examples, the X-ray powder diffraction pattern of the asiatic acid-cyclodextrin inclusion complex cocrystal is substantially as follows: Figure 4 shown.

[0045] In some examples, the mass percentage of asiatic acid in the asiatic acid-cyclodextrin inclusion compound eutectic is 10% to 12%. It is understandable that the mass percentage of asiatic acid includes but is not limited to: 10%, 10.2%, 10.4%, 10.6%, 10.8%, 11%, 11.2%, 11.4%, 11.5%, 11.6%, 11.8%, 12%.

[0046] In some examples, the particle size of the asiatic acid-cyclodextrin inclusion compound cocrystal is 1 μm to 3 μm. It can be understood that the particle size of the asiatic acid-cyclodextrin inclusion compound cocrystal includes but is not limited to: 1 μm, 1.2 μm, 1.4 μm, 1.5 μm, 1.6 μm, 1.8 μm, 2 μm, 2.2 μm, 2.3 μm, 2.5 μm, 2.7 μm, 3 μm.

[0047] In some of these examples, the crystals of asiatic acid-cyclodextrin inclusion complex cocrystals were short rod-shaped.

[0048] Combination Figure 1 The present application also provides a method for preparing the above-mentioned Centella asiatica acid-cyclodextrin inclusion complex cocrystal, comprising the following steps:

[0049] Mixing asiatic acid with a first solvent to prepare an asiatic acid solution;

[0050] mixing cyclodextrin with water to prepare a cyclodextrin aqueous solution;

[0051] The cyclodextrin aqueous solution is heated to 30° C. to 60° C., and then the asiatic acid solution is added to prepare a mixed solution;

[0052] The mixed solution was cooled, allowed to stand, and the precipitated solid was collected;

[0053] The first solvent is an organic solvent miscible with water.

[0054] On the one hand, the first solvent can be used as a solvent for asiatic acid and a solvent and delivery medium for the drug. When the asiatic acid solution is injected into the cyclodextrin aqueous solution, the first solvent can quickly mix with water molecules, thereby reducing the solubility of asiatic acid in the mixed solvent and the formation of inclusion complex; on the other hand, the organic solvent can be used as a poor solvent for cyclodextrin, promoting the precipitation of the inclusion complex from the solution in the form of a eutectic.

[0055] In some examples, the first solvent is selected from one or more of methanol, ethanol, acetonitrile, acetone, tetrahydrofuran, isopropanol, propylene glycol, and ethylene glycol.

[0056] In some of the examples, in the mixed solution, the volume ratio of the first solvent to water is 3:(7-60).

[0057] It can be understood that in the mixed liquid, the volume ratio of the first solvent to water includes but is not limited to: 3:7, 3:8, 3:9, 3:10, 3:11, 3:12, 3:13, 3:14, 3:15, 3:20, 3:25, 3:30, 3:35, 3:40, 3:45, 3:50, 3:55, and 3:60.

[0058] More specifically, a fixed volume of Centella asiatica solution is injected into the cyclodextrin aqueous solution, and the ratio of organic solvent to water is controlled within a certain range, such as methanol: water = 1:20-3:7; ethanol: water = 1:20-3:7; acetonitrile: water = 1:20-3:7; acetone: water = 1:20-3:7; isopropanol: water = 1:20-3:7; propylene glycol: water = 1:20-3:7; ethylene glycol: water = 1:20-3:7. When the Centella asiatica acid solvent is insufficient, blank solvent can be used to supplement it to the above solvent / water ratio range.

[0059] In some of the examples, the molar ratio of asiatic acid to cyclodextrin in the mixed solution is 1:(1-20).

[0060] It can be understood that in the mixed solution, the molar ratio of Centella asiatica to cyclodextrin includes but is not limited to: 1:1, 1:2, 1:3, 1:4, 1:5, 1:10, 1:15, 1:16, 1:17, 1:18, 1:19, 1:20.

[0061] In some of the examples, the concentration of asiatic acid in the asiatic acid solution is 0.5 mg / mL to 5 mg / mL.

[0062] In some of these examples, the concentration of cyclodextrin in the cyclodextrin aqueous solution is 3 mg / mL to 50 mg / mL. More specifically, the concentration of γ-cyclodextrin in the γ-cyclodextrin aqueous solution is 3 mg / mL to 30 mg / mL. It can be understood that in the present invention, the concentration of γ-cyclodextrin in the γ-cyclodextrin aqueous solution includes but is not limited to: 3 mg / mL, 5 mg / mL, 7 mg / mL, 10 mg / mL, 11 mg / mL, 12 mg / mL, 13 mg / mL, 14 mg / mL, 15 mg / mL, 16 mg / mL, 17 mg / mL, 18 mg / mL, 19 mg / mL, 20 mg / mL, 25 mg / mL, 30 mg / mL.

[0063] In some of the examples, during the process of adding the asiatic acid solution, based on 1 mL to 3 mL of the asiatic acid solution, the adding time is controlled to be 0.5 min to 30 min.

[0064] It can be understood that in the process of adding the asiatic acid solution, based on 1 mL to 3 mL of the asiatic acid solution, the time for controlling the addition includes but is not limited to: 0.5 min, 0.6 min, 0.7 min, 0.8 min, 1 min, 1.2 min, 1.4 min, 1.5 min, 1.6 min, 1.7 min, 1.8 min, 1.9 min, 2 min, 2.1 min, 2.2 min, 2.3 min, 2.4 min, 2.5 min, 3 min, 4 min, 5 min, 6 min, 7 min, 8 min, 10 min, 15 min, 20 min, 25 min, 30 min. Preferably, the time for controlling the addition is 2 min.

[0065] In some of the examples, during the addition of the asiatic acid solution, the cyclodextrin aqueous solution was stirred at a rotation speed of 50 rpm to 1000 rpm.

[0066] It can be understood that during the process of adding the Centella asiatica acid solution, the rotation speed of stirring the cyclodextrin aqueous solution includes but is not limited to: 50rpm, 51rpm, 52rpm, 53rpm, 54rpm, 55rpm, 60rpm, 70rpm, 80rpm, 90rpm, 100rpm, 200rpm, 300rpm, 400rpm, 500rpm, 600rpm, 700rpm, 800rpm, 900rpm, and 1000rpm.

[0067] In some of the examples, the mixed liquid is cooled to 4°C to 25°C.

[0068] In some examples, the temperature was allowed to stand for 24 to 72 hours.

[0069] In some examples, the following steps are included after collecting the precipitated solids:

[0070] The precipitated solid is filtered, washed with acetonitrile 1 to 3 times, and the white solid is collected; then the white solid is dried at 30° C. to 60° C. for 1 to 24 hours.

[0071] Further, in some of the examples, the hemolysis rate of the lung-targeted formulation is ≤5%.

[0072] In some examples, the lung-targeted formulation is an intravenous formulation.

[0073] In some of these examples, the lung-targeted agent is an agent for treating acute lung injury.

[0074] In some of these examples, the treatment of acute lung injury refers to a reduction in inflammatory cell infiltration of lung tissue.

[0075] In some of these examples, the treatment of acute lung injury refers to a reduction in pulmonary interstitial proliferation.

[0076] In some of these examples, the treatment of acute lung injury refers to a reduction in pulmonary edema.

[0077] In some of these examples, the treating acute lung injury refers to reducing lung congestion.

[0078] Some other examples of the present application provide the use of asiatic acid-cyclodextrin inclusion compound co-crystal in treating lung diseases.

[0079] In some examples, the cyclodextrin is γ-cyclodextrin.

[0080] In some examples, the X-ray powder diffraction pattern of the asiatic acid-cyclodextrin inclusion complex co-crystal has characteristic diffraction peaks at the following 2θ (°) angles:

[0081] : 7.5°±0.2°, 9.2°±0.2°, 10.6°±0.2°, 11.8°±0.2°, 14.2°±0.2°, 14.9°±0.2°, 15.8°±0.2°, 16.7°±0.2°, 19.2°±0.2°, 20.3°±0.2°, 21.2°±0.2°, 21.8°±0.2°, 22.5°±0.2°, 23.7°±0.2° and 26.6°±0.2°.

[0082] In some of the examples, the X-ray powder diffraction pattern of the asiatic acid-cyclodextrin inclusion complex cocrystal is substantially as follows: Figure 4 shown.

[0083] In some examples, the mass percentage of asiatic acid in the asiatic acid-cyclodextrin inclusion compound eutectic is 10% to 12%. It is understandable that the mass percentage of asiatic acid includes but is not limited to: 10%, 10.2%, 10.4%, 10.6%, 10.8%, 11%, 11.2%, 11.4%, 11.5%, 11.6%, 11.8%, 12%.

[0084] In some examples, the particle size of the asiatic acid-cyclodextrin inclusion compound cocrystal is 1 μm to 3 μm. It can be understood that the particle size of the asiatic acid-cyclodextrin inclusion compound cocrystal includes but is not limited to: 1 μm, 1.2 μm, 1.4 μm, 1.5 μm, 1.6 μm, 1.8 μm, 2 μm, 2.2 μm, 2.3 μm, 2.5 μm, 2.7 μm, 3 μm.

[0085] In some of these examples, the crystals of asiatic acid-cyclodextrin inclusion complex cocrystals were short rod-shaped.

[0086] Combination Figure 1 The present application also provides a method for preparing the above-mentioned Centella asiatica acid-cyclodextrin inclusion complex cocrystal, comprising the following steps:

[0087] Mixing asiatic acid with a first solvent to prepare an asiatic acid solution;

[0088] mixing cyclodextrin with water to prepare a cyclodextrin aqueous solution;

[0089] The cyclodextrin aqueous solution is heated to 30° C. to 60° C., and then the asiatic acid solution is added to prepare a mixed solution;

[0090] The mixed solution was cooled, allowed to stand, and the precipitated solid was collected;

[0091] The first solvent is an organic solvent miscible with water.

[0092] On the one hand, the first solvent can be used as a solvent for asiatic acid and a solvent and delivery medium for the drug. When the asiatic acid solution is injected into the cyclodextrin aqueous solution, the first solvent can quickly mix with water molecules, thereby reducing the solubility of asiatic acid in the mixed solvent and the formation of inclusion complex; on the other hand, the organic solvent can be used as a poor solvent for cyclodextrin, promoting the precipitation of the inclusion complex from the solution in the form of a eutectic.

[0093] In some examples, the first solvent is selected from one or more of methanol, ethanol, acetonitrile, acetone, tetrahydrofuran, isopropanol, propylene glycol, and ethylene glycol.

[0094] In some of the examples, in the mixed solution, the volume ratio of the first solvent to water is 3:(7-60).

[0095] It can be understood that in the mixed liquid, the volume ratio of the first solvent to water includes but is not limited to: 3:7, 3:8, 3:9, 3:10, 3:11, 3:12, 3:13, 3:14, 3:15, 3:20, 3:25, 3:30, 3:35, 3:40, 3:45, 3:50, 3:55, and 3:60.

[0096] More specifically, a fixed volume of Centella asiatica solution is injected into the cyclodextrin aqueous solution, and the ratio of organic solvent to water is controlled within a certain range, such as methanol: water = 1:20-3:7; ethanol: water = 1:20-3:7; acetonitrile: water = 1:20-3:7; acetone: water = 1:20-3:7; isopropanol: water = 1:20-3:7; propylene glycol: water = 1:20-3:7; ethylene glycol: water = 1:20-3:7. When the Centella asiatica acid solvent is insufficient, blank solvent can be used to supplement it to the above solvent / water ratio range.

[0097] In some of the examples, the molar ratio of asiatic acid to cyclodextrin in the mixed solution is 1:(1-20).

[0098] It can be understood that in the mixed solution, the molar ratio of Centella asiatica to cyclodextrin includes but is not limited to: 1:1, 1:2, 1:3, 1:4, 1:5, 1:10, 1:15, 1:16, 1:17, 1:18, 1:19, 1:20.

[0099] In some of the examples, the concentration of asiatic acid in the asiatic acid solution is 0.5 mg / mL to 5 mg / mL.

[0100] In some of these examples, the concentration of cyclodextrin in the cyclodextrin aqueous solution is 3 mg / mL to 50 mg / mL. More specifically, the concentration of γ-cyclodextrin in the γ-cyclodextrin aqueous solution is 3 mg / mL to 30 mg / mL. It can be understood that in the present invention, the concentration of γ-cyclodextrin in the γ-cyclodextrin aqueous solution includes but is not limited to: 3 mg / mL, 5 mg / mL, 7 mg / mL, 10 mg / mL, 11 mg / mL, 12 mg / mL, 13 mg / mL, 14 mg / mL, 15 mg / mL, 16 mg / mL, 17 mg / mL, 18 mg / mL, 19 mg / mL, 20 mg / mL, 25 mg / mL, 30 mg / mL.

[0101] In some of the examples, during the process of adding the asiatic acid solution, based on 1 mL to 3 mL of the asiatic acid solution, the adding time is controlled to be 0.5 min to 30 min.

[0102] It can be understood that in the process of adding the asiatic acid solution, based on 1 mL to 3 mL of the asiatic acid solution, the time for controlling the addition includes but is not limited to: 0.5 min, 0.6 min, 0.7 min, 0.8 min, 1 min, 1.2 min, 1.4 min, 1.5 min, 1.6 min, 1.7 min, 1.8 min, 1.9 min, 2 min, 2.1 min, 2.2 min, 2.3 min, 2.4 min, 2.5 min, 3 min, 4 min, 5 min, 6 min, 7 min, 8 min, 10 min, 15 min, 20 min, 25 min, 30 min. Preferably, the time for controlling the addition is 2 min.

[0103] In some of the examples, during the addition of the asiatic acid solution, the cyclodextrin aqueous solution was stirred at a rotation speed of 50 rpm to 1000 rpm.

[0104] It can be understood that during the process of adding the Centella asiatica acid solution, the rotation speed of stirring the cyclodextrin aqueous solution includes but is not limited to: 50rpm, 51rpm, 52rpm, 53rpm, 54rpm, 55rpm, 60rpm, 70rpm, 80rpm, 90rpm, 100rpm, 200rpm, 300rpm, 400rpm, 500rpm, 600rpm, 700rpm, 800rpm, 900rpm, and 1000rpm.

[0105] In some of the examples, the mixed liquid is cooled to 4°C to 25°C.

[0106] In some examples, the temperature was allowed to stand for 24 to 72 hours.

[0107] In some examples, the following steps are included after collecting the precipitated solids:

[0108] The precipitated solid is filtered, washed with acetonitrile 1 to 3 times, and the white solid is collected; then the white solid is dried at 30° C. to 60° C. for 1 to 24 hours.

[0109] Further, in some of the examples, the hemolysis rate of the lung-targeted formulation is ≤5%.

[0110] In some examples, the treating the lung disease is performed by intravenous injection.

[0111] In some examples, the lung disease is acute lung injury.

[0112] In some examples, the treatment of lung disease refers to reducing inflammatory cell infiltration of lung tissue.

[0113] In some examples, the treatment of a lung disease refers to a reduction in pulmonary interstitial proliferation.

[0114] In some examples, the treating a lung disease is a reduction in pulmonary edema.

[0115] In some examples, the treating a lung disease refers to reducing lung congestion.

[0116] The following are specific examples.

[0117] Example 1

[0118] This embodiment provides a Centella asiatica acid-cyclodextrin inclusion compound co-crystal, and the specific preparation process is as follows:

[0119] (1) Prepare a γ-cyclodextrin aqueous solution and an asiatic acid solution respectively, wherein the solvent of the asiatic acid solution is acetonitrile, the concentration of asiatic acid is 3 mg / mL, and the concentration of γ-cyclodextrin in the γ-cyclodextrin aqueous solution is 10 mg / mL.

[0120] (2) Heat the cyclodextrin aqueous solution to 50°C; inject 1 mL of the asiatic acid solution into 7 mL of the γ-cyclodextrin aqueous solution while stirring at 50 rpm for 2 minutes, add 2 mL of acetonitrile, and continue stirring for 0.5 minutes.

[0121] (3) Stop heating and stirring, and cool the mixed solution of Centella asiatica and cyclodextrin to 4° C.; and leave it for 12 hours until the crystals in the solution are completely precipitated.

[0122] (4) The white solid was filtered off and washed three times with 4°C acetonitrile; the product was then dried under vacuum at 40°C for 24 hours to obtain a white powder, which is the Asiatic acid-cyclodextrin inclusion complex eutectic. The yield of the product was 75% based on Asiatic acid, wherein the Asiatic acid content was about 11.5%.

[0123] Morphology and particle size characterization: The prepared Centella asiatica acid-cyclodextrin inclusion complex cocrystal was placed on a glass slide, and the morphology of the sample was observed and recorded under an optical microscope (10×20). Figure 2 As shown in FIG. 1 , the asiatic acid-cyclodextrin inclusion complex cocrystal has a clear crystal habit and is short rod-shaped. The particle size was measured by DLS and was 1878±348.9 nm. The particle size distribution is shown in FIG. Figure 3 shown.

[0124] Crystalline characterization: XPRD spectrum of Asiatic acid-cyclodextrin inclusion complex cocrystal is as follows Figure 4 The XRD diffraction peaks of the asiatic acid-cyclodextrin inclusion complex cocrystal are at 7.5°, 9.2°, 10.6°, 11.8°, 14.2°, 14.9°, 15.8°, 16.7°, 19.2°, 20.3°, 21.2°, 21.8°, 22.5°, 23.7°, and 26.6°, and the characteristic diffraction peaks of XPRD are completely different from those of asiatic acid and γ-CD, indicating that it is not a simple physical mixture, but a new crystal form has been formed.

[0125] Example 2

[0126] This example is an in vitro safety study of the asiatic acid-cyclodextrin inclusion complex co-crystal prepared in Example 1.

[0127] Experimental method: The asiatic acid-cyclodextrin inclusion complex cocrystal prepared in Example 1 was prepared into different concentrations (0.1 mg / mL, 0.2 mg / mL, 0.3 mg / mL, 0.4 mg / mL, and 0.5 mg / mL) according to the therapeutic dose of 10 mg / kg, and added to a 5% standard red blood cell suspension. After incubation at 37°C for 3 hours, the supernatant was centrifuged for 10 minutes at a centrifugal speed of 5000 rpm. The supernatant was then taken and its absorbance at 540 nm was measured using an ELISA instrument. The positive control was to add the same volume of double distilled water (H2O) to the red blood cell suspension. 2 O), and the negative control was the same volume of saline (0.9% NaCl) in the red blood cell suspension.

[0128] The preparation method of 5% standard red blood cell suspension is as follows: take 1mL of whole blood, add 3mL of isotonic saline, shake the centrifugal precipitate thoroughly (1000rpm, 10min), discard the supernatant, and then add 3mL of normal saline, wash according to the above method for a total of three times, finally take 1 drop of packed red blood cells, add 19 drops of fresh isotonic saline, and shake gently to obtain the required 5% standard red blood cell suspension.

[0129] Experimental results: Figure 5 As shown, compared with the negative control and the positive control, the hemolysis rates of the asiatic acid-cyclodextrin inclusion complex cocrystal at different concentrations were all lower than 5%, indicating that the cocrystal has good safety and can be used for intravenous administration.

[0130] Example 3

[0131] This example is an investigation of the lung targeting effect of the asiatic acid-cyclodextrin inclusion complex co-crystal prepared in Example 1.

[0132] Experimental method: The asiatic acid-cyclodextrin inclusion complex cocrystal prepared in Example 1 was administered by tail vein injection at a therapeutic dose of 10 mg / kg. The heart, liver, spleen, lung and kidney tissues of the mice were taken out at 0.25 h, 0.5 h, 1 h and 2 h, respectively, and the organic reagent ethyl acetate was added to make a homogenate, and then centrifuged at 10000 rpm and 4 ° C for 15 minutes. The supernatant was taken, dried, and then 300 μL of methanol was added for re-dissolution, and the asiatic acid concentration in each tissue was detected by high performance liquid chromatography.

[0133] Experimental results: Figure 6 As shown in Figure 2, 0.5 hours after administration, the drug content in the lung tissue of mice reached C max The drug content in heart, kidney and spleen tissues was much lower than that in lung tissue, indicating that the asiatic acid-cyclodextrin inclusion complex cocrystal has a highly efficient lung tissue targeting effect.

[0134] Example 4

[0135] This example is an investigation of the acute lung injury model of the asiatic acid-cyclodextrin inclusion complex cocrystal prepared in Example 1.

[0136] Experimental method: Figure 7 As shown, 24 balb / c male mice (6-8 weeks) were randomly divided into 4 groups (n=6, control group, LPS group, LPS+asiatic acid (aa) group, LPS+eutectic (aa / γ-CD) group). Except for the control group, all groups were instilled with LPS (10 mg / kg) through the trachea (step I). 4 hours after modeling, the LPS+asiatic acid (aa) group and the LPS+eutectic (aa / γ-CD) group were injected into the tail vein (step II) at a dose of 10 mg / kg. After 20 hours of administration, the mice were killed and the lung tissues were removed for HE staining analysis (step III). See the schematic diagram of the process for details. Figure 7 .

[0137] Experimental results: Figure 8 As shown, the treatment effect of Centella asiatica acid-cyclodextrin inclusion complex cocrystal was the best, which significantly improved the inflammatory cell infiltration, pulmonary interstitial hyperplasia, edema and congestion of lung tissue.

[0138] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0139] The above-described embodiments only express several implementation methods of the present application, which is convenient for understanding the technical solution of the present application in detail, but it cannot be understood as limiting the scope of protection of the patent application. It should be pointed out that for ordinary technicians in this field, without departing from the concept of the present application, several modifications and improvements can be made, which all belong to the scope of protection of the present application. It should be understood that the technical solutions obtained by those skilled in the art through logical analysis, reasoning or limited experiments on the basis of the technical solutions provided in the present application are all within the scope of protection of the claims attached to the present application. Therefore, the scope of protection of the patent of this application shall be based on the contents of the attached claims, and the description and drawings may be used to interpret the contents of the claims.

Claims

1. Application of Centella asiatica acid-cyclodextrin inclusion complex cocrystal in the preparation of lung-targeted preparations.

2. The use according to claim 1, characterized in that: The cyclodextrin is γ-cyclodextrin.

3. The use according to claim 2, characterized in that: The X-ray powder diffraction pattern of the asiatic acid-cyclodextrin inclusion complex co-crystal has characteristic diffraction peaks at the following 2θ (°) angles: : 7.5°±0.2°, 9.2°±0.2°, 10.6°±0.2°, 11.8°±0.2°, 14.2°±0.2°, 14.9°±0.2°, 15.8°±0.2°, 16.7°±0.2°, 19.2°±0.2°, 20.3°±0.2°, 21.2°±0.2°, 21.8°±0.2°, 22.5°±0.2°, 23.7°±0.2° and 26.6°±0.2°.

4. The use according to claim 2, characterized in that: The X-ray powder diffraction pattern of the asiatic acid-cyclodextrin inclusion complex co-crystal is substantially as shown in FIG4 .

5. The use according to claim 1, characterized in that: In the asiatic acid-cyclodextrin inclusion compound eutectic, the mass percentage of asiatic acid is 10% to 12%.

6. The use according to claim 1, characterized in that: The particle size of the asiatic acid-cyclodextrin inclusion complex cocrystal is 1 μm to 3 μm.

7. The use according to any one of claims 1 to 6, characterized in that: The hemolysis rate of the lung targeting preparation is ≤5%.

8. The use according to any one of claims 1 to 6, characterized in that: The lung-targeted preparation is an intravenous injection preparation.

9. The use according to any one of claims 1 to 6, characterized in that: The lung-targeted preparation is a preparation for treating acute lung injury.

10. The use according to claim 9, characterized in that: The method for treating acute lung injury has at least one of the following characteristics (1) to (4): (1) Decreased inflammatory cell infiltration in lung tissue; (2) decreased pulmonary interstitial proliferation; (3) reduction in pulmonary edema; (4) Reduced pulmonary congestion.

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