High drug-loading porous breviscapine spherulite and preparation method thereof

Abstract

The application provides a high-drug-loading porous breviscapine crystal and a preparation method thereof. The crystal is prepared by a solvent diffusion method, does not contain auxiliary materials, and has high drug purity. The crystal is a highly porous, spherical, round, particle-size-controllable, large-particle-size crystal particle, and is easy to implement in an industrial scale. The process is green, and the crystal is crystallized in an aqueous solution. The solvents used can be recycled and reused. The porous breviscapine crystal prepared by the application has rapid in-vitro dissolution, improved flowability and compressibility, and is beneficial to further preparation molding.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of medicine, in particular to a high drug-loading breviscapine porous spherocrystal and a process for preparing the same. BACKGROUND

[0002] Breviscapine is a flavonoid extracted and refined from the traditional Chinese medicine Herba erigerontis, which is the main effective component of Herba erigerontis. Breviscapine is a mixture of scutellarin B and scutellarin A, with scutellarin B as the main component, accounting for more than 95%. Breviscapine has the effects of anticoagulation, antithrombosis, improving blood rheology and microcirculation, increasing cerebral blood flow, resisting myocardial ischemia, and improving the body's ability to resist hypoxia. Related preparations, including tablets and injection solutions, are commonly used drugs for treating cardiovascular and cerebrovascular diseases, and have definite clinical efficacy.

[0003] Breviscapine is almost insoluble in water and other solvents such as acetone and dichloromethane, and has very low oral bioavailability. The raw material of breviscapine is generally irregularly shaped and has poor flowability and slow in-vitro dissolution. In the process of manufacturing granules, compressed tablets, and filled capsules, a large amount of auxiliary materials need to be added to improve the powder properties, assist the formation of the preparation, and promote the dissolution of the drug.

[0004] In pharmacy, granulation methods are generally used to improve the flowability and compressibility of powders, including different granulation processes: spray drying can directly prepare loose spherical particles from liquid materials, fluidized granulation can prepare composite particles and coated particles, and extrusion-spheronization technology can obtain spherical or quasi-spherical pellets with tight texture. The above methods all belong to conventional preparation technology, each having its own advantages and disadvantages, and all need to add appropriate auxiliary materials and use corresponding equipment.

[0005] The prior art CN200710150318 discloses a traditional Chinese medicine granule containing breviscapine and a preparation method thereof, specifically, a fluidized bed granulation technology is used to prepare granules with good fluidity by using breviscapine and carrier excipients. The prior art "Design and evaluation of inhalable nanocrystals embedded microparticles with enhanced redispersibility and bioavailability for breviscapine" (Yingchong Chen et al., Powder Technology, 377:128-138, 2021) discloses a specific method for preparing breviscapine microspheres by spray drying process, which first prepares a nanosuspension of breviscapine; then adds mannitol, lactose or maltodextrin to prepare drug-loaded microspheres by spray drying; the obtained microspheres have an aerodynamic diameter of 1-5 μm, are spherical under a scanning electron microscope, and have different sizes, the in vitro dissolution is significantly faster than that of the raw material drug, and is especially suitable for pulmonary inhalation administration. The above granulation technologies all need to add a large amount of excipients and use specific equipment to form breviscapine granules.

[0006] In addition, the physical properties of drug particles can also be improved by using spherical crystallization granulation technology. This technology uses the action of bridging agents to make the drug crystallize in the liquid phase and agglomerate at the same time, and under the action of stirring and shearing, spherical particles are formed. There are two specific processes: one is wet spherical agglomeration, which dissolves the drug in a good solvent and heats it, adds a small amount of bridging agent, mixes well, and then adds the above mixed solution to a poor solvent, stirs under cooling conditions to make the particles agglomerate and precipitate; the bridging agent needs to be immiscible with the poor solvent but has better solubility for the drug, and the appropriate bridging agent and solvent system need to be selected through experiments. The second is emulsion solvent diffusion, which first forms a drug solution into a droplet, with the diffusion of the solvent in the droplet, the drug precipitates, solidifies, and remains spherical; the selection of the inner and outer phase solvents is crucial to the quality of spherical crystal formation.

[0007] The prior art CN201210085634 discloses a solid self-microemulsion based on the technology of spherulite and its preparation method. In the process of spherulite granulation, various adjuvants such as surfactants, high molecular materials, pore-forming agents and dispersion carriers are added to prepare solid self-microemulsion type spherulites from poorly soluble drugs, so as to improve the dissolution and dissolution. However, the proportion of the poorly soluble drug is only 5% to 25%, and the drug loading capacity is low. The prior art CN201610638915 discloses a spherulite type menthol particle direct pressure preparation and its preparation method. Through the wet granulation process, the menthol is gathered in the three-component liquid phase system of bridging agent-good solvent-poor solvent to form spherical particles with smooth and flat surface. The prior art "Relationship between Glycyrrhetic Acid Spherulite Particle Size and In Vitro Dissolution Behavior" (Wu Yanan et al., Chinese Traditional and Herbal Drugs, 47(12):2841-2844, 2019) discloses a method for preparing poorly soluble glycyrrhetic acid spherulites by emulsified solvent diffusion process. The obtained spherulites have dense and compact surface, a small amount of internal voids, and the in vitro dissolution is significantly delayed compared with the raw material drug. The above spherulite granulation technology can obtain spherical and spherical drug crystal particles, but the obtained spherulites have no significant porous structure, so it cannot effectively improve the dissolution of the drug.

[0008] The prior art CN200610035980.4 discloses a scutellaria barbata polymeric nanoparticle preparation prepared from scutellaria barbata, polymer and surfactant, wherein the weight ratio of scutellaria barbata and polymer is 1:5-20. The preparation method is as follows: 1 part by weight of scutellaria barbata and 5-20 parts by weight of polymer are completely dissolved in an appropriate amount of volatile organic solvent to form a mixed solution A; 2) 0.04-0.32 parts by weight of surfactant is added to an appropriate amount of water to prepare a surfactant aqueous solution B with a mass percentage concentration of 0.5%-4.0%; 3) then solution A is added dropwise into solution B to form a mixed solution C; 4) the mixed solution C is stirred thoroughly at room temperature until the volatile organic solvent is completely volatilized; 5) the obtained filtrate is sterilized and then packaged after being filtered through a microporous filter membrane to obtain a scutellaria barbata polymeric nanoparticle suspension preparation. However, a large amount of polymer adjuvant is required to promote the aggregation of the particles during the preparation of the scutellaria barbata polymeric particles in the above prior art, otherwise the scutellaria barbata cannot be self-aggregated into particles. Moreover, the above particles are nanoscale particles with small particle size and poor flowability, which are not suitable for further preparation.

[0009] Unlike the above prior art, the high drug loading scutellaria barbata porous spherulites of the present application do not contain any adjuvant, have high drug loading capacity, are prepared by using conventional equipment and process, and have simple and efficient preparation method. The obtained spherulites have high loose and porous structure, improved flowability and compressibility, faster in vitro dissolution, and provide convenient conditions for subsequent preparation and rapid drug release. SUMMARY

[0010] The purpose of the present application is to provide a high drug loading scrophularine crystal with a porous structure. Using the above-mentioned crystal, the powder properties of the raw drug can be improved, the flowability and compressibility thereof are increased, and in particular, the dissolution performance of scrophularine is significantly increased, facilitating further processing and disposal in the preparation process.

[0011] In the prior art, due to the special properties of scrophularine, in particular, its solubility in neither water nor conventional solvents such as acetone and dichloromethane, it is still not possible to prepare scrophularine into a crystal, and if spherical particles are needed, a large amount of polymer and other excipients are required, and the particle size is in the nanometer level. Due to the small particle size, the flowability is poor, and the drug loading is low. The inventor team has tried to prepare scrophularine crystals by wet granulation, but found that due to the inability to aggregate and precipitate scrophularine particles, the crystal cannot be formed (see CN2023102204341). The inventor team found that scrophularine can be cross-linked and aggregated by carrying hydroxyl groups and other groups, and based on this property, a scrophularine crystal without excipients was prepared, which has a high drug loading, a micron-level particle size, good flowability, and in particular, a large number of pores on the surface of the crystal, internal radial pores, and a hollow core region, with the characteristics of fast dissolution rate.

[0012] Specifically, the present application provides the following technical solutions:

[0013] A high drug loading scrophularine porous crystal, characterized in that: the crystal is free of excipients, the surface and the inside of the crystal are porous, and the internal and external pores are connected, the core region is hollow, the particle size of the crystal is 1-100 μm, the spherical shape is round and uniform, and the rest angle is less than 35°.

[0014] In the present application, "the crystal is free of excipients" means that no excipients for aggregation are used in the crystal, such as polylactic acid or lactic acid-hydroxyethyl glycol copolymer, etc. It may contain a small amount of stabilizers that prevent the adhesion and merging of crystals during stirring, such as PVA, but the amount is small enough not to affect the overall properties of the crystal itself.

[0015] Further, compared with the raw drug, the crystallinity of the high drug loading scrophularine porous crystal is significantly reduced, which is manifested as the disappearance of diffraction peaks or the significant reduction of peak intensity in the detection of powder X-ray diffractometer.

[0016] Further, the flowability of the high drug loading scrophularine porous crystal is significantly increased, with a rest angle value smaller than that of scrophularine raw drug, such as the rest angle less than 35° as described above. Preferably, less than 34°, 33°, 32°.

[0017] Further, compared with the raw drug, the compressibility of the high drug loading scrophularine porous crystal is significantly increased, with a Carr index less than 24 and a Hausner ratio less than 1.3.

[0018] Further, the particle size of the high drug loading porous scutellarein spherocrystal is suitable for further preparation, and the particle size is 1-100 μm. Preferably, the particle size is 5-70 μm, and more preferably, the particle size is 10-50 μm.

[0019] Another object of the present application is to provide a preparation method of the high drug loading porous scutellarein spherocrystal, which is simple and controllable. Specifically, the present application provides the following technical solution: A preparation method of high drug loading porous scutellarein spherocrystal, characterized in that an emulsification solvent evaporation method is used, an appropriate amount of scutellarein raw material is weighed, an organic good solvent is added to completely dissolve it, and then another organic solvent system is mixed uniformly to obtain an oil phase, the solution is added to an aqueous phase containing a stabilizer to prepare a primary emulsion, the primary emulsion is continuously diluted to make the organic solvent diffuse into the aqueous phase, and after continuous stirring, the organic solvent of the oil phase is volatilized, the spherical particles are solidified, and then dried to obtain the product.

[0020] Preferably, the stabilizer is polyvinyl alcohol. More preferably, the aqueous phase containing the stabilizer is a 0.2-3% polyvinyl alcohol aqueous solution. Preferably, it is a 0.3-2% polyvinyl alcohol aqueous solution. More preferably, it is a 0.5-1% polyvinyl alcohol aqueous solution.

[0021] The preferred good solvent is one or more of dimethyl sulfoxide, N,N-dimethylformamide, N-methyl pyrrolidone, N,N-diethylacetamide, and pyridine; more preferably, the good solvent is dimethyl sulfoxide.

[0022] The preferred another organic solvent system is an organic solvent system obtained by mixing one or more organic solvents selected from dichloromethane or ethyl acetate with one or more organic solvents selected from dioxane, acetone. Preferably, the volume ratio of the one or more organic solvents selected from dichloromethane or ethyl acetate in the another organic solvent system is not less than 40%. More preferably, the volume ratio of the one or more organic solvents selected from dichloromethane or ethyl acetate in the another organic solvent system is not less than 45%. More preferably, the volume ratio of the one or more organic solvents selected from dichloromethane or ethyl acetate in the another organic solvent system is 50%-55%.

[0023] Preferably, the other organic solvent system is a mixed solvent system of dichloromethane, dioxane and acetone; more preferably, the volume ratio of dichloromethane, dioxane and acetone is 4-8:2-4:0-4, and the volume ratio of dichloromethane is not less than 40%; more preferably, the volume ratio of dichloromethane, dioxane and acetone is 4-6:2-4:0-3, and the volume ratio of dichloromethane is not less than 40%; more preferably, the volume ratio of dichloromethane, dioxane and acetone is 5:2:3, and the volume ratio of dichloromethane is not less than 40%.

[0024] Preferably, the volume ratio of the good solvent to the other organic solvent system is 1:10-40; preferably, the volume ratio is 1:10-20; more preferably, the volume ratio is 1:15-20.

[0025] The mixing can be assisted by stirring, shearing, ultrasonic and the like, and the preferred method is stirring, and the particle size of the emulsion droplets can be controlled by adjusting the stirring speed.

[0026] The spherulites obtained in the application are mainly in a non-crystalline state, have good fluidity and faster dissolution rate. Non-limitingly, the inventors believe that the above-mentioned effect of improving the dissolution is related to the high-porosity structure, i.e., the structure leads to high specific surface area of the spherulites, facilitates the penetration and infiltration of the solvent, and speeds up the dissolution of the drug.

[0027] The high-drug-loading porous spherulites of scutellarein provided by the application are simple to prepare, low in price and good in reproducibility.

[0028] The application dissolves scutellarein in a good solvent first, then adds another organic solvent system selected by a specific method, obtains an oil phase suitable for preparing spherulites of scutellarein, adds the oil phase into an aqueous phase containing a stabilizer, and uses the emulsion solvent evaporation method to innovatively prepare high-drug-loading porous spherulites of scutellarein, thereby overcoming the technical difficulty that scutellarein cannot be prepared into high-drug-loading spherulites in the prior art. The application utilizes the synergistic effect of various organic solvents, so that scutellarein can be crosslinked and attracted by hydroxyl groups and the like during the evaporation of the organic solvent, thereby unexpectedly aggregating. Without using auxiliary materials, scutellarein is focused into a spherulite-like particle shape, a good preparation intermediate is obtained, and the product form and the method for preparing the product are neither reported nor expected in the existing literature of scutellarein.

[0029] In summary, the inventors found that, by using a proper solvent system to prepare high-drug-loading breviscapine spherulites, a highly porous structure can be formed, thereby significantly accelerating the dissolution of the active ingredient, and the powder flowability and compressibility are also improved. Moreover, no auxiliary materials or special equipment are needed in the process of preparing the spherulites, which saves cost and facilitates large-scale production.

[0030] BRIEF DESCRIPTION OF DRAWINGS Figure 1 Micrographs of the breviscapine crystals after solidification in Examples 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, and 20.

[0031] Figure 2 Micrographs of the breviscapine crystals after solidification in Comparative Examples 1, 2, 3, 4, 5, 6, and 7.

[0032] Figure 3 Appearance photographs (left) and scanning electron microscope (right) images of breviscapine bulk drug (A, B) and high-purity porous spherulites (C, D) in Example 1.

[0033] Figure 4 (A) Nitrogen adsorption-desorption curve, (B) BJH desorption pore size distribution, (C) powder X-ray diffraction pattern, and (D) Fourier transform infrared spectroscopy pattern of the high-drug-loading breviscapine porous spherulites in Example 1.

[0034] Figure 5 In vitro dissolution curves of breviscapine bulk drug and high-purity porous spherulites in Example 1 in different pH media (Mean ± SD; n=3); in which, A graph uses pH 5 phosphate buffer as the dissolution medium, and B graph uses pH 6.8 phosphate buffer as the dissolution medium (*P<0.05 compared with the bulk drug group).

[0035] The technical solutions in the embodiments of the present application will be described clearly and completely in combination with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. IMPLEMENTATION

[0036] Example 1: 10 mg of breviscapine raw material was weighed, 50 μl of dimethyl sulfoxide was added to make it completely dissolved, and then 200 μl of dioxane was added and mixed; under vortex, the above solution was added dropwise to a mixed solvent of 300 μl of acetone and 500 μl of dichloromethane (as an oil phase); under stirring (960 rpm / min), the above oil phase was quickly injected into 20 ml of 1% polyvinyl alcohol (as an aqueous phase), and stirring was continued for 10 min to obtain a primary emulsion; 30 ml of 0.5% polyvinyl alcohol aqueous solution was added to the primary emulsion, stirring and solidification was continued for 3 h, and standing was continued for 1 h; the precipitate was separated by centrifugation, washed with a small amount of water for 3 times, and collected; after pre-freezing for 4 h, continuous freeze-drying was carried out for 48 h to obtain breviscapine porous spherical crystals.

[0037] Example 2: 10 mg of breviscapine raw material was weighed, 50 μl of dimethyl sulfoxide was added to make it completely dissolved, and then 200 μl of dioxane was added and mixed; under vortex, the above solution was added dropwise to a mixed solvent of 300 μl of acetone and 500 μl of dichloromethane (as an oil phase); under stirring (960 rpm / min), the above oil phase was quickly injected into 20 ml of 3% polyvinyl alcohol (as an aqueous phase), and stirring was continued for 10 min to obtain a primary emulsion; 30 ml of 0.5% polyvinyl alcohol aqueous solution was added to the primary emulsion, stirring and solidification was continued for 3 h, and standing was continued for 1 h; the precipitate was separated by centrifugation, washed with a small amount of water for 3 times, and collected; after pre-freezing for 4 h, continuous freeze-drying was carried out for 48 h to obtain breviscapine porous spherical crystals.

[0038] Example 3: 10 mg of breviscapine raw material was weighed, 50 μl of dimethyl sulfoxide was added to make it completely dissolved, and then 200 μl of dioxane was added and mixed; under vortex, the above solution was added dropwise to a mixed solvent of 300 μl of acetone and 500 μl of dichloromethane (as an oil phase); under stirring (960 rpm / min), the above oil phase was quickly injected into 20 ml of 2% polyvinyl alcohol (as an aqueous phase), and stirring was continued for 10 min to obtain a primary emulsion; 30 ml of 0.5% polyvinyl alcohol aqueous solution was added to the primary emulsion, stirring and solidification was continued for 3 h, and standing was continued for 1 h; the precipitate was separated by centrifugation, washed with a small amount of water for 3 times, and collected; after pre-freezing for 4 h, continuous freeze-drying was carried out for 48 h to obtain breviscapine porous spherical crystals.

[0039] Example 4: 10 mg of breviscapine raw material was weighed, 50 μl of dimethyl sulfoxide was added to make it completely dissolved, then 200 μl of dioxane was added, and mixed; under vortex, the above solution was added dropwise to a mixed solvent of 300 μl of acetone and 500 μl of dichloromethane (as an oil phase); under stirring (960 rpm / min), the above oil phase was quickly injected into 20 ml of 1% polyvinyl alcohol (as an aqueous phase), and stirring was continued for 10 min to obtain a primary emulsion; 30 ml of 0.3% polyvinyl alcohol aqueous solution was added to the primary emulsion, and stirring and solidification were continued for 3 h, and then standing for 1 h; the precipitate was separated by centrifugation, washed with a small amount of water for 3 times, and the precipitate was collected; after pre-freezing for 4 h, continuous freeze-drying was carried out for 48 h to obtain breviscapine porous spherical crystals.

[0040] Example 5: 10 mg of breviscapine raw material was weighed, 50 μl of dimethyl sulfoxide was added to make it completely dissolved, then 200 μl of dioxane was added, and mixed; under vortex, the above solution was added dropwise to a mixed solvent of 300 μl of acetone and 500 μl of dichloromethane (as an oil phase); under stirring (960 rpm / min), the above oil phase was quickly injected into 20 ml of 1% polyvinyl alcohol (as an aqueous phase), and stirring was continued for 10 min to obtain a primary emulsion; 30 ml of 0.2% polyvinyl alcohol aqueous solution was added to the primary emulsion, and stirring and solidification were continued for 3 h, and then standing for 1 h; the precipitate was separated by centrifugation, washed with a small amount of water for 3 times, and the precipitate was collected; after pre-freezing for 4 h, continuous freeze-drying was carried out for 48 h to obtain breviscapine porous spherical crystals.

[0041] Example 6: 10 mg of breviscapine raw material was weighed, 50 μl of N,N-dimethylformamide was added to make it completely dissolved, then 200 μl of dioxane was added, and mixed; under vortex, the above solution was added dropwise to a mixed solvent of 300 μl of acetone and 500 μl of dichloromethane (as an oil phase); under stirring (960 rpm / min), the above oil phase was quickly injected into 20 ml of 1% polyvinyl alcohol (as an aqueous phase), and stirring was continued for 10 min to obtain a primary emulsion; 30 ml of 0.5% polyvinyl alcohol aqueous solution was added to the primary emulsion, and stirring and solidification were continued for 3 h, and then standing for 1 h; the precipitate was separated by centrifugation, washed with a small amount of water for 3 times, and the precipitate was collected; after pre-freezing for 4 h, continuous freeze-drying was carried out for 48 h to obtain breviscapine crystals.

[0042] Example 7: Weigh 10 mg of breviscapine raw material, add 50 μl of N-methyl pyrrolidone to make it completely dissolved, then add 200 μl of dioxane, mix well; under vortex state, add the above solution drop by drop to the mixed solvent of 300 μl of acetone and 500 μl of ethyl acetate (as oil phase); under the condition of stirring (960 rpm / min), quickly inject the above oil phase into 20 ml of 1% polyvinyl alcohol (as water phase), continue to stir for 10 min to obtain the initial emulsion; add 30 ml of 0.5% polyvinyl alcohol aqueous solution to the initial emulsion, stir and solidify for 3 h, stand for 1 h, then centrifugal separate the precipitate, wash with a small amount of water for 3 times, collect the precipitate; pre-freeze for 4 h, then continue to freeze dry for 48 h to obtain breviscapine crystals.

[0043] Example 8: Weigh 10 mg of breviscapine raw material, add 50 μl of N, N-diethylacetamide to make it completely dissolved, then add 200 μl of dioxane, mix well; under vortex state, add the above solution drop by drop to the mixed solvent of 300 μl of acetone and 500 μl of dichloromethane (as oil phase); under the condition of stirring (960 rpm / min), quickly inject the above oil phase into 20 ml of 1% polyvinyl alcohol (as water phase), continue to stir for 10 min to obtain the initial emulsion; add 30 ml of 0.5% polyvinyl alcohol aqueous solution to the initial emulsion, stir and solidify for 3 h, stand for 1 h, then centrifugal separate the precipitate, wash with a small amount of water for 3 times, collect the precipitate; pre-freeze for 4 h, then continue to freeze dry for 48 h to obtain breviscapine crystals.

[0044] Example 9: Weigh 10 mg of breviscapine raw material, add 100 μl of DMSO to make it completely dissolved, then add 200 μl of dioxane, mix well; under vortex state, add the above solution drop by drop to the mixed solvent of 300 μl of acetone and 500 μl of dichloromethane (as oil phase); under the condition of stirring (960 rpm / min), quickly inject the above oil phase into 20 ml of 1% polyvinyl alcohol (as water phase), continue to stir for 10 min to obtain the initial emulsion; add 30 ml of 0.5% polyvinyl alcohol aqueous solution to the initial emulsion, stir and solidify for 3 h, stand for 1 h, then centrifugal separate the precipitate, wash with a small amount of water for 3 times, collect the precipitate; pre-freeze for 4 h, then continue to freeze dry for 48 h to obtain breviscapine crystals.

[0045] Example 10: 10 mg of breviscapine raw material was weighed, 66.6 μl of DMSO was added to make it completely dissolved, and then 200 μl of dioxane was added and mixed; under vortex, the above solution was added dropwise to a mixed solvent of 300 μl of acetone and 500 μl of dichloromethane (as an oil phase); under stirring (960 rpm / min), the above oil phase was quickly injected into 20 ml of 1% polyvinyl alcohol (as an aqueous phase), and stirring was continued for 10 min to obtain a primary emulsion; 30 ml of 0.5% polyvinyl alcohol aqueous solution was added to the primary emulsion, and stirring and solidification were continued for 3 h, and after standing for 1 h, the precipitate was separated by centrifugation, washed with a small amount of water for 3 times, and the precipitate was collected; after pre-freezing for 4 h, continuous freeze-drying was carried out for 48 h to obtain breviscapine crystals.

[0046] Example 11: 10 mg of breviscapine raw material was weighed, 25 μl of DMSO was added to make it completely dissolved, and then 200 μl of dioxane was added and mixed; under vortex, the above solution was added dropwise to a mixed solvent of 300 μl of acetone and 500 μl of dichloromethane (as an oil phase); under stirring (960 rpm / min), the above oil phase was quickly injected into 20 ml of 1% polyvinyl alcohol (as an aqueous phase), and stirring was continued for 10 min to obtain a primary emulsion; 30 ml of 0.5% polyvinyl alcohol aqueous solution was added to the primary emulsion, and stirring and solidification were continued for 3 h, and after standing for 1 h, the precipitate was separated by centrifugation, washed with a small amount of water for 3 times, and the precipitate was collected; after pre-freezing for 4 h, continuous freeze-drying was carried out for 48 h to obtain breviscapine crystals.

[0047] Example 12: 10 mg of breviscapine raw material was weighed, 50 μl of DMSO was added to make it completely dissolved, and then 200 μl of dioxane was added and mixed; under vortex, the above solution was added dropwise to a mixed solvent of 400 μl of acetone and 400 μl of dichloromethane (as an oil phase); under stirring (960 rpm / min), the above oil phase was quickly injected into 20 ml of 1% polyvinyl alcohol (as an aqueous phase), and stirring was continued for 10 min to obtain a primary emulsion; 30 ml of 0.5% polyvinyl alcohol aqueous solution was added to the primary emulsion, and stirring and solidification were continued for 3 h, and after standing for 1 h, the precipitate was separated by centrifugation, washed with a small amount of water for 3 times, and the precipitate was collected; after pre-freezing for 4 h, continuous freeze-drying was carried out for 48 h to obtain breviscapine crystals.

[0048] Example 13: Weigh 10 mg breviscapine raw material, add 50 μl DMSO to make it completely dissolved, then add 400 μl dioxane, mix well; under vortex, add the above solution drop by drop to 600 μl dichloromethane (as oil phase); under stirring (960 rpm / min), quickly inject the above oil phase into 20 ml 1% polyvinyl alcohol (as aqueous phase), continue stirring for 10 min to obtain the primary emulsion; add 30 ml 0.5% polyvinyl alcohol aqueous solution to the primary emulsion, stir and solidify for 3 h, after standing for 1 h, centrifugal separation of the precipitate, add a small amount of water to wash 3 times, collect the precipitate; pre-freeze for 4 h, then continue freeze-drying for 48 h to obtain breviscapine crystals.

[0049] Example 14: Weigh 10 mg breviscapine raw material, add 50 μl DMSO to make it completely dissolved, then add 200 μl dioxane, mix well; under vortex, add the above solution drop by drop to 800 μl dichloromethane (as oil phase); under stirring (960 rpm / min), quickly inject the above oil phase into 20 ml 1% polyvinyl alcohol (as aqueous phase), continue stirring for 10 min to obtain the primary emulsion; add 30 ml 0.5% polyvinyl alcohol aqueous solution to the primary emulsion, stir and solidify for 3 h, after standing for 1 h, centrifugal separation of the precipitate, add a small amount of water to wash 3 times, collect the precipitate; pre-freeze for 4 h, then continue freeze-drying for 48 h to obtain breviscapine crystals.

[0050] Example 15: Weigh 10 mg breviscapine raw material, add 50 μl DMSO to make it completely dissolved, then add 200 μl dioxane, mix well; under vortex, add the above solution drop by drop to 300 μl acetone and 500 μl dichloromethane mixed solvent (as oil phase); under shearing (3000 rpm, 1 min), quickly inject the above oil phase into 20 ml 1% polyvinyl alcohol (as aqueous phase) to obtain the primary emulsion; add 30 ml 0.5% polyvinyl alcohol aqueous solution to the primary emulsion, stir and solidify for 3 h, after standing for 1 h, centrifugal separation of the precipitate, add a small amount of water to wash 3 times, collect the precipitate; pre-freeze for 4 h, then continue freeze-drying for 48 h to obtain breviscapine crystals.

[0051] Example 16: Weigh 5 mg of scutellarein raw material, add 50 μl of DMSO to make it completely dissolved, then add 200 μl of dioxane, mix well; under vortex, add the above solution drop by drop to the mixed solvent of 300 μl of acetone and 500 μl of dichloromethane (as oil phase); under stirring (960 rpm / min), quickly inject the above oil phase into 20 ml of 1% polyvinyl alcohol (as water phase), continue stirring for 10 min to obtain the initial emulsion; add 30 ml of 0.5% polyvinyl alcohol aqueous solution to the initial emulsion, stir and solidify for 3 h, stand for 1 h, then centrifugal separate the precipitate, wash with a small amount of water for 3 times, collect the precipitate; pre-freeze for 4 h, then continue freeze-drying for 48 h to obtain scutellarein crystals.

[0052] Example 17: Weigh 15 mg of scutellarein raw material, add 50 μl of DMSO to make it completely dissolved, then add 200 μl of dioxane, mix well; under vortex, add the above solution drop by drop to the mixed solvent of 300 μl of acetone and 500 μl of dichloromethane (as oil phase); under stirring (960 rpm / min), quickly inject the above oil phase into 20 ml of 1% polyvinyl alcohol (as water phase), continue stirring for 10 min to obtain the initial emulsion; add 30 ml of 0.5% polyvinyl alcohol aqueous solution to the initial emulsion, stir and solidify for 3 h, stand for 1 h, then centrifugal separate the precipitate, wash with a small amount of water for 3 times, collect the precipitate; pre-freeze for 4 h, then continue freeze-drying for 48 h to obtain scutellarein crystals.

[0053] Example 18: Weigh 10 mg of scutellarein raw material, add 50 μl of DMSO to make it completely dissolved, then add 200 μl of dioxane, mix well; under vortex, add the above solution drop by drop to the mixed solvent of 300 μl of acetone and 500 μl of dichloromethane (as oil phase); under stirring (640 rpm / min), quickly inject the above oil phase into 20 ml of 1% polyvinyl alcohol (as water phase), continue stirring for 10 min to obtain the initial emulsion; add 30 ml of 0.5% polyvinyl alcohol aqueous solution to the initial emulsion, stir and solidify for 3 h, stand for 1 h, then centrifugal separate the precipitate, wash with a small amount of water for 3 times, collect the precipitate; pre-freeze for 4 h, then continue freeze-drying for 48 h to obtain scutellarein crystals.

[0054] Example 19: Weigh 10 mg of scutellarin raw material, add 50 μl of DMSO to dissolve it completely, then add 200 μl of dioxane and mix well; under vortex conditions, add the above solution dropwise to a mixed solvent of 300 μl of acetone and 500 μl of dichloromethane (as the oil phase); under stirring (1440 rpm / min), rapidly inject the above oil phase into 20 ml of 1% polyvinyl alcohol (as the aqueous phase), and continue stirring for 10 min to obtain the primary emulsion; add 30 ml of 0.5% polyvinyl alcohol aqueous solution to the primary emulsion, stir and solidify for 3 h, let stand for 1 h, centrifuge to separate the precipitate, wash three times with a small amount of water, and collect the precipitate; pre-freeze for 4 h and then freeze-dry for 48 h to obtain scutellarin crystals.

[0055] Example 20: Weigh 10 mg of scutellarin raw material, add 50 μl of DMSO to dissolve it completely, then add 200 μl of dioxane and mix well; under vortex conditions, add the above solution dropwise to a mixed solvent of 300 μl of acetone and 500 μl of dichloromethane (as the oil phase); under stirring (2400 rpm / min), rapidly inject the above oil phase into 20 ml of 1% polyvinyl alcohol (as the aqueous phase), and continue stirring for 10 min to obtain the pre-emulsion; add 30 ml of 0.5% polyvinyl alcohol aqueous solution to the pre-emulsion, stir and solidify for 3 h, let stand for 1 h, centrifuge to separate the precipitate, wash three times with a small amount of water, and collect the precipitate; pre-freeze for 4 h and then freeze-dry for 48 h to obtain scutellarin crystals.

[0056] Take an appropriate amount of the cured *Erigeron breviscapus* crystalline powder, observe its particle size, morphology, and degree of aggregation under an optical microscope, and record the observations by photograph. Microscopic observations of crystallization in Examples 1-20. Figure 1 The results showed that the crystals obtained in the above examples were all spherical or near-spherical under an optical microscope, with relatively uniform particle size and excellent roundness, although the particle sizes varied. Comparative Examples 1-7 (specific preparation methods are described later) showed the following microscopic examination of the crystals. Figure 2 The results showed that, under an optical microscope, Comparative Examples 1-3 exhibited disordered, sheet-like crystals, and none of them yielded spherical crystals; Comparative Example 4, after solidification, was a clear solution, and no scutellarin crystals were obtained.

[0057] The appearance of the raw material of *Erigeron breviscapus* extract and the porous spherulite powder of Example 1 were observed with the naked eye, and the samples were also observed under a scanning electron microscope. The results are shown in the figure. Figure 3 The results showed that the raw material of *Dendrobium nobile* (a type of medicinal ingredient)... Figure 3 A) and the spherulites obtained in Example 1 ( Figure 3 C) are both pale yellow powders, with more loosely packed spherulites. Under a scanning electron microscope, the raw material of *Ligustrum lucidum* (…) Figure 3 B) consists of slender, rod-shaped crystals tightly packed together in irregular clumps, with significant size variations; the spherulites obtained in Example 1 ( Figure 3D) The spheres are formed by the adhesion of plate-like crystals, which are 10-50 μm in size. The surface has a large number of interconnected pores. When individual particles break, they expose dense radial channels with a cross-section. The core area of ​​the sphere is hollow.

[0058] Characterization of porous spherulite powder: An appropriate amount of the porous spherulite powder obtained in Example 1 was used to determine the N2 adsorption-desorption isotherm and pore size distribution using a fully automated specific surface area and porosity analyzer. The results are shown in […]. Figure 4 A and Figure 4 B. The results showed that the specific surface area of ​​the product obtained in Example 1 was 52.11 m². 2 / g, total pore volume is 0.11cm³ 3 / g and an average pore size of 8.07nm. N2 adsorption-desorption isotherms of porous spherulites ( Figure 4 A) is a type IV isotherm, and the adsorption isotherm and desorption isotherm form a distinct H3 type hysteresis loop; pore size distribution curve ( Figure 4 B) It can be seen that porous spherulites contain macropores, micropores, and mesopores, with mesopores accounting for the highest proportion. An appropriate amount of the porous spherulite powder obtained in Example 1 was scanned using a powder X-ray diffractometer, and the results are shown below. Figure 4 C. The results showed that, compared with the active pharmaceutical ingredient, the diffraction peaks of the product obtained in Example 1 disappeared or decreased in intensity, indicating a significant decrease in crystallinity. An appropriate amount of the porous spherulite powder obtained in Example 1 was scanned using a Fourier transform infrared spectroscopy (FTIR) instrument; the results are shown below. Figure 4 D. The results showed that the infrared spectrum of the porous spherulites obtained in Example 1 was basically consistent with that of the active pharmaceutical ingredient, but the intensity of several peaks was reduced, indicating that the formation of spherulites was only a physical process and no new chemical bonds were formed.

[0059] The in vitro dissolution behavior of porous spherulites of scutellarin was tested using pH 5 phosphate buffer and pH 6.8 phosphate buffer as the release media, at a temperature of (37±0.5℃) and a rotation speed of 50 rpm / min. A small amount of scutellarin raw material and porous spherulite powder (Example 1) were accurately weighed into the release media. Samples were taken at predetermined time points, filtered through a 0.22 μm microporous membrane, and the filtrate was analyzed by high-performance liquid chromatography (HPLC) to determine the scutellarin content. The cumulative dissolution rate was calculated, and a dissolution curve was plotted. The results are shown below. Figure 5 As shown. The results show that when the medium is pH 5 phosphate buffer (… Figure 5 In step A), drug dissolution is relatively slow. The cumulative dissolution rates of the active pharmaceutical ingredient (API) and spherulites after 12 hours are 26% and 48%, respectively, with the spherulites showing approximately 1.8 times the dissolution rate of the API. The medium is pH 6.8 phosphate buffer (pH 6.8). Figure 5B), the drug dissolution is faster, the cumulative dissolution of the raw material and the spherulite is about 77% and 91% respectively in 1 min; the cumulative dissolution of the raw material reaches 82% and that of the spherulite reaches 100% in 3 min. In the two aqueous media, the drug release of the porous spherulite is superior to that of the raw material, and the advantage is more obvious in the acidic medium.

[0060] The powder properties of the porous spherulite of scutellarein were characterized. A funnel was fixed above the coordinate paper placed horizontally, and scutellarein raw material and the porous spherulite powder obtained in Example 1 were slowly poured into the funnel respectively until the funnel mouth contacted the tip of the conical sample. The radius R and height H of the conical sample were measured, and the rest angle θ was calculated according to the formula tanθ = H / R. A certain amount (M) of scutellarein raw material and the porous spherulite powder sample obtained in Example 1 were loaded into a graduated cylinder with a known volume (bulk volume V0), and the bulk density = M / V0 was calculated. The powder in the graduated cylinder was tapped until the volume (V) no longer changed, and the tap density = M / V was calculated. The Carr index = (tap density - bulk density) / tap density × 100% was calculated; and the Hausner ratio = tap density / bulk density. The results are shown in Table 1.

[0061] Table 1 Key performance parameters of scutellarein raw material and high drug loading scutellarein porous spherulite

[0062] Parameter Scutellarein raw material Scutellarein porous crystal Rest angle (°) 40.63±1.44 31.59±2.32* Bulk density (g / cm3) 0.22±0.01 0.22±0.01 Tapped density (g / cm3) 0.30±0.01 0.27±0.01 Carr index 28.54±1.09 17.65±0.46* Hausner ratio 1.40±0.02 1.21±0.01

[0063] *P < 0.05 VS scutellarein raw material

[0064] The results in Table 1 show that after the scutellarein raw material is prepared into a porous spherulite, the rest angle is reduced from 40.63 to 31.59, and the flowability is significantly improved. The Carr index and the Hausner ratio of the porous spherulite are lower than those of the raw material, indicating that the compressibility of the porous spherulite is improved.

[0065] The following experiment was also conducted in the screening process of the present application, which is given as a comparative example:

[0066] Comparative Example 1: 10 mg of scutellarein raw material was weighed, 50 μl of DMSO was added to completely dissolve it, and then 200 μl of dioxane was added and mixed. Under vortex, the above solution was added dropwise to a mixed solvent of 300 μl of acetone and 500 μl of dichloromethane (as an oil phase). Under stirring (1300 rpm, 10 min), the above oil phase was quickly injected into 20 ml of 1% povidone K30 (as an aqueous phase) to obtain a primary emulsion. 30 ml of 0.5% povidone K30 aqueous solution was added to the primary emulsion, and stirred and solidified for 3 h. After standing for 1 h, the precipitate was separated by centrifugation, washed with a small amount of water for 3 times, and collected. After pre-freezing for 4 h, continuous freeze-drying was carried out for 48 h to obtain scutellarein crystals.

[0067] Comparative Example 2: 10 mg scutellarein raw material was weighed, 50 μl dimethyl sulfoxide was added to completely dissolve the scutellarein, and then 200 μl dioxane was added to mix well; under vortex, the solution was added dropwise to 300 μl mixed solvent of acetone and dichloromethane (as oil phase); under stirring (1500 rpm, 10 min), the oil phase was quickly injected into 20 ml 1% hydroxypropyl methyl cellulose E50 (as aqueous phase) to obtain a primary emulsion; 30 ml 0.5% hydroxypropyl methyl cellulose E50 aqueous solution was added to the primary emulsion, and stirring and solidification were performed for 3 h; after standing for 1 h, the precipitate was separated by centrifugation, washed with a small amount of water for 3 times, and collected; after pre-freezing for 4 h, continuous freeze-drying was performed for 48 h to obtain scutellarein crystals.

[0068] Comparative Example 3: 10 mg scutellarein raw material was weighed, 50 μl dimethyl sulfoxide was added to completely dissolve the scutellarein, and then 200 μl dioxane was added to mix well; under vortex, the solution was added dropwise to 300 μl mixed solvent of acetone and dichloromethane (as oil phase); under stirring (1500 rpm, 10 min), the oil phase was quickly injected into 20 ml water to obtain a primary emulsion; 30 ml water was added to the primary emulsion, and stirring and solidification were performed for 3 h; after standing for 1 h, the precipitate was separated by centrifugation, washed with a small amount of water for 3 times, and collected; after pre-freezing for 4 h, continuous freeze-drying was performed for 48 h to obtain scutellarein crystals.

[0069] Comparative Example 4: 10 mg scutellarein raw material was weighed, 50 μl pyridine was added to completely dissolve the scutellarein, and then 200 μl dioxane was added to mix well; under vortex, the solution was added dropwise to 300 μl mixed solvent of acetone and dichloromethane (as oil phase); under stirring (100 rpm, 10 min), the oil phase was quickly injected into 20 ml 1% polyvinyl alcohol (as aqueous phase) to obtain a primary emulsion; 30 ml 0.5% polyvinyl alcohol aqueous solution was added to the primary emulsion, and stirring and solidification were performed for 3 h; after standing for 1 h, the precipitate was separated by centrifugation, washed with a small amount of water for 3 times, and collected; after pre-freezing for 4 h, continuous freeze-drying was performed for 48 h to obtain scutellarein crystals.

[0070] Comparative Example 5: 10 mg scutellarein raw material was weighed, 50 μl dimethyl sulfoxide was added to completely dissolve the scutellarein, and then 200 μl dioxane was added and mixed; under vortex, the above solution was added dropwise to a mixed solvent of 300 μl acetone and 300 μl dichloromethane (as an oil phase); under ultrasonic (ultrasonic power 30%, ultrasonic on time 5 s, ultrasonic off time 5 s, ultrasonic total time 1 min), the above oil phase was quickly injected into 20 ml 1% polyvinyl alcohol (as an aqueous phase) to obtain a primary emulsion; 30 ml 0.5% polyvinyl alcohol aqueous solution was added to the primary emulsion, and stirring and solidification were performed for 3 h; after standing for 1 h, the precipitate was separated by centrifugation, washed with a small amount of water for 3 times, and the precipitate was collected; after pre-freezing for 4 h, continuous freeze-drying was performed for 48 h to obtain scutellarein crystals.

[0071] Comparative Example 6: 10 mg scutellarein raw material was weighed, 50 μl dimethyl sulfoxide was added to completely dissolve the scutellarein, and then 200 μl dioxane was added and mixed; under vortex, the above solution was added dropwise to a mixed solvent of 300 μl acetone and 500 μl dichloromethane (as an oil phase); under high shear (6000 rpm, 1 min), the above oil phase was quickly injected into 20 ml 1% polyvinyl alcohol (as an aqueous phase) to obtain a primary emulsion; 30 ml 0.5% polyvinyl alcohol aqueous solution was added to the primary emulsion, and stirring and solidification were performed for 3 h; after standing for 1 h, the precipitate was separated by centrifugation, washed with a small amount of water for 3 times, and the precipitate was collected; after pre-freezing for 4 h, continuous freeze-drying was performed for 48 h to obtain scutellarein crystals.

[0072] Comparative Example 7: 20 mg scutellarein raw material was weighed, 50 μl dimethyl sulfoxide was added to completely dissolve the scutellarein, and then 200 μl dioxane was added and mixed; under vortex, the above solution was added dropwise to a mixed solvent of 300 μl acetone and 200 μl dichloromethane (as an oil phase); under stirring (speed 1300, 10 min), the above oil phase was quickly injected into 20 ml 1% polyvinyl alcohol (as an aqueous phase) to obtain a primary emulsion; 30 ml 0.5% polyvinyl alcohol aqueous solution was added to the primary emulsion, and stirring and solidification were performed for 3 h; after standing for 1 h, the precipitate was separated by centrifugation, washed with a small amount of water for 3 times, and the precipitate was collected; after pre-freezing for 4 h, continuous freeze-drying was performed for 48 h to obtain scutellarein crystals.

[0073] The above is only a preferred embodiment of the present application, and it should be noted that the above preferred embodiment should not be regarded as a limitation of the present application, and the protection scope of the present application should be limited by the scope defined in the claims. For ordinary skilled persons in the art, several improvements and refinements can be made without departing from the spirit and scope of the present application, and these improvements and refinements should also be regarded as the protection scope of the present application.

Claims

1. A high drug loading porous scutellarein crystal with improved dissolution of scutellarein, characterized in that, The spherical crystal is without auxiliary materials, the surface and the inside of the spherical crystal are porous, and the inside and outside pores are connected, the center of the spherical crystal is hollow, the particle size of the spherical crystal is 1-100 μm, the spherical shape is round and uniform, and the rest angle is less than 35°; The preparation method of the high-drug-loading scutellarein porous spherical crystal is as follows: an appropriate amount of scutellarein raw material is weighed, an organic good solvent is added to completely dissolve the scutellarein, and then another organic solvent system is mixed to obtain an oil phase; the solution is added to an aqueous phase containing a stabilizer to stir to obtain a primary emulsion; the primary emulsion is continuously diluted to diffuse the organic solvent into the aqueous phase; the oil phase organic solvent is volatilized through continuous stirring; and the spherical particles are solidified and dried to obtain the high-drug-loading scutellarein porous spherical crystal; the aqueous phase containing the stabilizer is a 0.2-3% polyvinyl alcohol aqueous solution; The organic good solvent is one or more of dimethyl sulfoxide, N,N-dimethylformamide, N-methyl pyrrolidone, and N,N-diethylacetamide; The another organic solvent system is an organic solvent system obtained by mixing one or more organic solvents selected from dichloromethane or ethyl acetate and one or more organic solvents selected from dioxane and acetone, wherein the volume ratio of the one or more organic solvents selected from dichloromethane or ethyl acetate in the another organic solvent system is not less than 40%; and the stirring is selected from magnetic stirring or high-speed shearing at a speed of 640-2400 rpm.

2. The high drug-loaded porphysome of claim 1, wherein, The spherical crystal has disappeared diffraction peaks or reduced peak intensity relative to the raw material in powder X-ray diffraction instrument detection.

3. The method for preparing high drug-loaded porous scrophulariine crystal according to claim 1, characterized in that, The preparation method of the high-drug-loading scutellarein porous spherical crystal is as follows: an appropriate amount of scutellarein raw material is weighed, an organic good solvent is added to completely dissolve the scutellarein, and then another organic solvent system is mixed to obtain an oil phase; the solution is added to an aqueous phase containing a stabilizer to stir to obtain a primary emulsion; the primary emulsion is continuously diluted to diffuse the organic solvent into the aqueous phase; the oil phase organic solvent is volatilized through continuous stirring; and the spherical particles are solidified and dried to obtain the high-drug-loading scutellarein porous spherical crystal; the aqueous phase containing the stabilizer is a 0.2-3% polyvinyl alcohol aqueous solution; The organic good solvent is one or more of dimethyl sulfoxide, N,N-dimethylformamide, N-methyl pyrrolidone, and N,N-diethylacetamide; The another organic solvent system is an organic solvent system obtained by mixing one or more organic solvents selected from dichloromethane or ethyl acetate and one or more organic solvents selected from dioxane and acetone, wherein the volume ratio of the one or more organic solvents selected from dichloromethane or ethyl acetate in the another organic solvent system is not less than 40%; and the stirring is selected from magnetic stirring or high-speed shearing at a speed of 640-2400 rpm. The another organic solvent system is a mixed solvent system of dichloromethane, dioxane, and acetone, and the volume ratio of the dichloromethane, dioxane, and acetone is 4-8:2-4:0-4, wherein the volume ratio of the dichloromethane in the another organic solvent system is not less than 40%.

4. The production method according to claim 3, characterized by, The volume ratio of the organic good solvent to the another organic solvent system is 1:10-40.

5. The preparation method according to claim 3, characterized in that, ​

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