Preparation method and application of spray curing nano-carrier powder for improving bioavailability of silymarin

Abstract

The invention discloses a preparation method and application of silymarin spray curing nano-carrier powder, and relates to the technical field of medicines and the field of foods. The method comprises the following steps: firstly, constructing a silymarin-carrier compound through a molecular self-assembly technology, and then, carrying out curing treatment on a nano-carrier by adopting a spray drying technology, so as to obtain nano-powder with good flowability. According to the preparation method disclosed by the invention, the silymarin spray curing nano-carrier powder with a core-shell structure is successfully prepared by optimizing a carrier material ratio and spray drying conditions. Experimental results show that the spray-cured nano-carrier powder prepared by the method significantly improves the solubility and stability of silymarin, and enhances the bioavailability and efficacy, so that silymarin can be more efficiently absorbed and released in a targeted manner in vivo, thereby significantly improving the therapeutic effect.

Description

Technical Field

[0001] The invention relates to the fields of medical technology and food, and in particular to a preparation method and application of a spray-cured nano-carrier powder for increasing the bioavailability of silymarin. Background Art

[0002] Milk thistle belongs to the genus Silybum in the Asteraceae family. It is an annual or biennial herb, and can also be called milk thistle, mouse tendon, milk thistle, and milk thistle. Silymarin is a mixture of flavonolignan compounds, which is light yellow to brownish yellow and easily soluble in organic solvents such as methanol, ethanol, and ethyl acetate. It mainly contains three active ingredients, namely silybin, silybinin, and silybintin. Among them, silybin is the effective active ingredient that exerts biological effects.

[0003] Silymarin has significant antioxidant properties and can effectively remove free radicals that are harmful to the liver, thereby reducing oxidative stress indicators and alleviating liver damage. This substance can interact with phospholipids on the liver cell membrane, enhance the stability of the cell membrane, and thus reduce damage to liver cells. After liver damage occurs, silymarin can also promote the regeneration of liver cells. Therefore, it is used to treat diseases such as cirrhosis, hepatitis, liver fibrosis and liver damage. In addition, silymarin also exhibits multiple biological activities such as neuromodulation, immunomodulation, cardiovascular protection and anti-cancer.

[0004] With the change of lifestyle, the incidence of liver disease is gradually increasing. In terms of diet, the intake of high-calorie, high-fat foods will increase saturated fatty acids and cholesterol, increase the burden on the liver, and cause non-alcoholic fatty liver disease; a high-sugar diet will convert glucose into fatty acids in the liver, further aggravating fat accumulation. Excessive drinking will convert alcohol into acetaldehyde, directly damaging liver cells and leading to alcoholic hepatitis. In life, people's lack of exercise leads to excess energy, causing obesity and non-alcoholic fatty liver disease; staying up late disrupts the biological rhythm of liver enzymes and reduces metabolism and detoxification efficiency.

[0005] Although silymarin has been widely used in clinical practice, its solubility in water is very low and its oral bioavailability is also relatively low. In view of the above shortcomings, a silymarin spray-cured nanocarrier powder is prepared, the raw material is combined with appropriate excipients, and a new dosage form is prepared through a new formulation technology to improve its pharmacokinetic properties and enhance the bioavailability of silymarin.

[0006] Currently, the commercially available silymarin-related products are mainly used for liver protection, such as Legalon silymarin capsules produced by Pfizer, Silybum marianum, Pueraria lobata, and Salvia miltiorrhiza tablets produced by BY-HEALTH, and silymarin seed oil soft capsules imported directly from the United States. However, the poor bioavailability of silymarin directly affects the full exertion of its efficacy. Therefore, the bioavailability of silymarin can be improved by developing new silymarin preparations, such as preparing liposomes and nanoparticles.

[0007] As a new type of drug delivery system, spray-dried nano-carriers can efficiently encapsulate various drug types, and their unique solid powder form significantly improves the physical stability and long-term storage performance of the preparation. This carrier system shows unique advantages in improving the bioavailability of poorly soluble drugs, protecting active ingredients from enzymatic degradation, and enabling pulmonary inhalation.

[0008] Chinese Invention Patent (Patent Application No. 202410808179.7, Publication No. CN118662480A, Application Date: June 21, 2024), with the invention title "A Silymarin Nanoliposome with High Bioavailability and Its Preparation Method" discloses a silymarin nanoliposome, whose main components are composed of silymarin extract, phosphatidylcholine, egg yolk lecithin, soybean lecithin, Tween 80, polyoxyethylene hydrogenated castor oil, polyethylene glycol, etc. This invention reduces the uptake of liposomes by mononuclear macrophages through the above excipients, thereby prolonging their circulation time in the body, which is significantly different from the formulation and solubilization principle of the present invention.

[0009] Chinese Invention Patent (Patent Application No. 202110696753.0, Publication No. CN113350311B, Application Date: June 23, 2021), with the invention title "A Silymarin Nanostructured Lipid Carrier and Its Preparation Method" discloses a silymarin nanostructured lipid carrier, whose active pharmaceutical ingredient and excipients are composed of silymarin, lecithin, isopropyl lauroylsarcosinate, glyceryl behenate, sodium lysinate, butanediol, water, etc., which is significantly different from the components of the present invention. Moreover, this nanostructure is prepared by the method of preparing an emulsion, and it is intended to enrich silymarin more in the epidermis and dermis to improve its bioavailability, which is significantly different from the main components and the technical route for improving bioavailability of the present invention.

[0010] Chinese invention patent (Patent Application No. 201610003996.0, Publication No. CN105687159A, Application Date: January 4, 2016), with the invention title "Preparation and Application of Silymarin Lipid Nanoparticles" discloses a silymarin nano-lipid particle. The raw materials used are silymarin, stearic acid, medium-chain glycerides, Tween, etc. Its preparation method is to drop the mixture into water containing Tween. Mainly, the lipid nanoparticles are used as a drug delivery carrier in the preparation of drugs for autism, aiming to enrich the drug in the inflammatory area and reduce the dosage. It is significantly different from the formulation, preparation method, and application scope of the present invention.

[0011] Chinese invention patent (Patent Application No. 202410939001.6, Publication No. CN118453545A, Application Date: July 15, 2024), with the invention title "Silymarin Targeted Oil-based Nanodelivery System and Its Preparation Method and Application" discloses a silymarin targeted oil-based nanodelivery system. This system is composed of components such as soybean phospholipids, Tween 60, silymarin, glyceryl palmitate, glyceryl caprylate, glyceryl laurate, sucrose esters, etc. Its main purpose is to prepare a nanodelivery system that enables silymarin to be targeted and delivered to the liver by oral administration. It is significantly different from the main components and uses of the present invention.

[0012] Chinese invention patent (Patent Application No. 202310474871.6, Publication No. CN116421572A, Application Date: April 28, 2023), with the invention title "A Silymarin Solid Dispersion Sustained Release Tablet and Its Preparation Method" discloses a silymarin solid dispersion tablet, which delays the release rate of silymarin by tabletting to make it a sustained release preparation. This invention mainly utilizes new sustained release materials to fully utilize the active ingredients of silymarin, which is significantly different from the intention of the present invention to improve bioavailability through solubilization.

[0013] Chinese invention patent (Patent Application No. 202410996414.8, Publication No. CN118791522A, Application Date: July 24, 2024), with the invention title "A Preparation Method of Silymarin Phospholipid Complex and a Special Stirring Reactor" discloses a silymarin phospholipid complex. This complex is composed of silymarin medicinal materials, soybean phospholipids, lecithin, sunflower phospholipids, phosphatidylserine, L-α-glycerylphosphorylcholine, mono- and diglycerol fatty acid esters, polyglycerol fatty acid esters, Tween 20, Tween 80, sucrose fatty acid esters, etc. And it mainly introduces the preparation method of the silymarin phospholipid complex and a special stirring reactor, which is significantly different from the main components and main equipment of the present invention.

[0014] Chinese invention patent (Patent Application No.: 200910076989.3, Publication No.: CN101780047B, Application Date: January 16, 2009), with the invention title "A nano-microstructured silybin pharmaceutical composite powder and its preparation method" discloses a nano-microstructured silybin composite powder. This composite powder is spray-dried while carrying an organic solvent during the drying process, which is completely different from the process of the present invention that removes the organic solvent by a unique solvent replacement method and then performs spray drying.

[0015] Chinese invention patent (Patent Application No.: 200410014407.6, Publication No.: CN1264509C, Application Date: March 24, 2004), with the invention title "A pro-liposomal preparation containing silymarin extract and its preparation method" discloses a pro-liposome of silymarin extract. This pro-liposome contains a water-soluble carrier, a non-aqueous solution, a surfactant, and a film-forming material, and encapsulates the silymarin extract through these components that cannot dissociate in water. It is completely different from the preparation principle of the present invention that utilizes electrolytes to dissociate in water to form solid nano-carriers with charged surfaces.

[0016] The present invention adopts the form of silymarin spray-cured nano-carrier powder, and synergistically formulates it with excipients so that silymarin is encapsulated therein. As the core component, silymarin has powerful antioxidant and anti-inflammatory properties, can effectively scavenge free radicals, reduce oxidative stress damage to the liver, and promote the self-repair and regeneration of liver cells. It can significantly enhance the detoxification function of the liver, improve the metabolic environment of the liver, regulate lipid metabolism in the liver, and prevent and relieve various liver diseases. The encapsulation technology of the nano-carrier enables silymarin to be more precisely taken up by liver cells, with stronger targeting, higher drug concentration, and improved bioavailability. At the same time, the structure of the nano-carrier helps to protect the activity of silymarin, making it stable during in vivo transportation, reducing degradation and inactivation, with higher safety, mildness, and no irritation. Summary of the Invention

[0017] Silymarin is a BCS class IV drug with poor permeability and solubility and low oral bioavailability. The present invention provides a preparation method of silymarin spray-cured nano-carrier powder, which improves the solubility and bioavailability of silymarin on the one hand, and on the other hand, greatly enhances the stability of powdered silymarin, making it more conducive to storage.

[0018] The first object of the present invention is to: form a nano-carrier through the self-assembly of raw materials and excipients, and use spray drying technology to convert it into powder, significantly improving the solubility of silymarin, thereby improving its dispersibility and application performance in aqueous media.

[0019] The second purpose of the present invention is: the present invention prepares silymarin nanocarriers through a unique process, and the nano-scale carrier structure can change the way silymarin enters cells. Compared with the traditional form, it optimizes the cellular uptake pathway of the drug, making it easier to be absorbed by cells, thereby improving the drug delivery efficiency.

[0020] The third purpose of the present invention is that the nanocarrier technology can enhance the release and absorption of drugs in the body, significantly improve the bioavailability of silymarin, and achieve better therapeutic effects at lower doses.

[0021] The fourth object of the present invention is to utilize the high specific surface area and loading capacity of the nanocarrier to significantly increase the drug loading of silymarin, thereby reducing the amount of auxiliary materials, improving the drug efficacy per unit carrier, and reducing production costs.

[0022] The fifth object of the present invention is to solidify the nanocarrier into a powder through a spray drying process, thereby effectively improving the physical and chemical stability of silymarin, extending its shelf life and reducing degradation.

[0023] To achieve the above purpose, the technical solution provided by the present invention is as follows:

[0024] A silymarin spray-cured nano-carrier powder, characterized in that it comprises the following components in parts by weight: 5-40 parts of silymarin, 12-60 parts of phospholipids, 0.5-70 parts of a solubilizer, and 0.01-9 parts of an electrolyte.

[0025] Further preferably, the phospholipid is selected from one or more of the following components: sunflower lecithin, soybean lecithin, egg yolk lecithin, glycerophospholipids, diphosphatidylglycerol, dipalmitoylphosphatidylcholine, distearoylphosphatidylethanolamine-polyethylene glycol, cephalin, dimyristoylphosphatidylcholine, dipalmitoylphosphatidylethanolamine, and hydrogenated soybean lecithin.

[0026] Further preferably, the solubilizing agent is selected from one or more of the following components: cationic surfactants, anionic surfactants, nonionic surfactants, cyclodextrin and its derivatives, and polyethylene glycol.

[0027] Further preferably, the electrolyte is a substance that can dissociate into cations and anions in water, selected from one or more of the following components: sodium chloride, sodium bicarbonate, sodium citrate, sodium alginate, calcium chloride, sodium carboxymethyl cellulose, potassium nitrate, sodium dihydrogen phosphate.

[0028] Further preferably, the method for preparing the silymarin spray-cured nanocarrier powder is characterized by comprising the following steps:

[0029] (1) adding silymarin, phospholipid and fat-soluble solubilizing agent into an organic solvent in sequence and fully dissolving them;

[0030] (2) removing the organic solvent and replacing it with an aqueous electrolyte solution containing a water-soluble solubilizer;

[0031] (3) spray drying to obtain silymarin spray-cured nano-carrier powder.

[0032] Further preferably, the method for preparing the silymarin spray-cured nanocarrier powder is characterized in that: in step (1), the raw materials and auxiliary materials are fully dissolved by heating them in a water bath at 40-80°C to promote dissolution.

[0033] Further preferably, the method for preparing the silymarin spray-cured nanocarrier powder is characterized in that: in step (2), the method for removing the organic solvent is selected from one of the following methods: rotary evaporation, vacuum drying, and natural volatilization.

[0034] Further preferably, the method for preparing the silymarin spray-cured nanocarrier powder is characterized in that the spray drying conditions in step (3) are: the spray temperature is 110-200° C., the rotation speed is 5-30 rpm, and the atomization pressure is 0.1-0.4 MPa.

[0035] Further preferably, the method for preparing the silymarin spray-cured nanocarrier powder is characterized in that: in step (3), the particle size of the obtained spray-cured nanocarrier powder after redissolving in water is 10-200 nm.

[0036] Further preferred is the use of silymarin spray-cured nanocarrier powder in food, health products, skin care products, medical devices and medicines.

[0037] The technical solution provided by the present invention has the following beneficial effects compared with the prior art solution:

[0038] 1. The present invention focuses on the problem of poor solubility of silymarin and innovatively uses nanotechnology to precisely encapsulate silymarin. This breakthrough effectively improves the solubility of silymarin and greatly increases its bioavailability, opening up new ideas for the development of related fields.

[0039] 2. The present invention innovatively introduces solubilizers and electrolytes into the preparation process of spray-cured nanocarrier powders at the same time. The two play their respective roles in solubilization, but this experiment confirms for the first time that the two components are not simply superimposed, but produce significant synergistic effects, achieving the effect of "1+1>2", breaking through the limitations of traditional cognition.

[0040] 3. The present invention innovatively converts the nano-carrier into a powder state to prepare a powder preparation. Compared with the traditional preparation form, this powder preparation exhibits excellent stability, greatly extends the shelf life, has obvious advantages in storage and transportation, and can effectively reduce the logistics and warehousing costs.

[0041] 4. The present invention has a superior formulation ratio in improving the solubility of silymarin, achieving the loading of more drugs with the least amount of excipients. Moreover, the obtained preparation has significantly improved stability under normal temperature storage conditions, with uniform and stable dissolution, ensuring the rapid release of the drug in vivo and maintaining an effective blood drug concentration. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 It is the redissolution diagram of Example 1 and the dissolution diagram of water in ultrapure water of Comparative Example 8.

[0043] Figure 2 It is the SEM diagram of Comparative Example 8.

[0044] Figure 3 It is the SEM diagram of Example 1.

[0045] Figure 4 It is the cumulative release diagram of Example 1, Comparative Example 8 and Comparative Example 9 in a medium with a pH of 6.8.

[0046] Figure 5 It is the blood drug concentration-time curve diagram of Example 1, Comparative Example 8 and Comparative Example 9 within 0 - 24 h.

[0047] Figure 6 It is the blood drug concentration-time curve diagram of Example 1, Comparative Example 8 and Comparative Example 9 within 0 - 4 h. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0048] In order to better understand the purpose and technical solution of the present invention, the present invention will be described in more detail in combination with the following embodiments. The described embodiments are only a part of the embodiments of the present invention, and the embodiments are only used to explain the present invention. In addition, it should be understood that after reading the content described in the present invention, those skilled in the art make some non-essential changes or adjustments to the present invention, which still fall within the protection scope of the present invention.

[0049] S1 First, add 25 parts of silymarin, 20 parts of sunflower phospholipid, and 50 parts of Tween 80 to 200 ml of ethanol in sequence, and heat in a water bath at 50 °C to promote dissolution;

[0050] S2 Secondly, after the silymarin, sunflower phospholipids, and Tween 80 are completely dissolved, rotary evaporation is carried out at a temperature of 50 °C. After removing the organic solvent, 500 ml of sodium alginate aqueous solution is added for hydration. After the substances in the eggplant-shaped flask are completely dissolved, homogenization is carried out using a high-pressure homogenizer (5000 psi) to obtain the silymarin nanocarrier, which is the liquid to be sprayed;

[0051] S3 Finally, spray drying is carried out under the conditions of a temperature of 180 °C, a rotation speed of 20 rpm, and an atomization pressure of 0.2 MPa to obtain the silymarin spray-cured nanocarrier powder.

[0052] Example 2

[0053] S1 First, 25 parts of silymarin, 20 parts of egg yolk lecithin, and 50 parts of Tween 80 are successively added to 200 ml of ethanol, and heating is carried out in a water bath at 50 °C to promote dissolution;

[0054] S2 Secondly, after the silymarin, egg yolk lecithin, and Tween 80 are completely dissolved, rotary evaporation is carried out at a temperature of 50 °C. After removing the organic solvent, 500 ml of sodium alginate aqueous solution is added for hydration. After the substances in the eggplant-shaped flask are completely dissolved, homogenization is carried out using a high-pressure homogenizer (5000 psi) to obtain the silymarin nanocarrier, which is the liquid to be sprayed;

[0055] S3 Finally, spray drying is carried out under the conditions of a temperature of 180 °C, a rotation speed of 20 rpm, and an atomization pressure of 0.2 MPa to obtain the silymarin spray-cured nanocarrier powder.

[0056] Example 3

[0057] S1 First, 25 parts of silymarin, 20 parts of sunflower phospholipids, and 50 parts of Tween 80 are successively added to 200 ml of ethanol, and heating is carried out in a water bath at 50 °C to promote dissolution;

[0058] S2 Secondly, after the silymarin, sunflower phospholipids, and Tween 80 are completely dissolved, rotary evaporation is carried out at a temperature of 50 °C. After removing the organic solvent, 500 ml of sodium carboxymethylcellulose aqueous solution is added for hydration. After the substances in the eggplant-shaped flask are completely dissolved, homogenization is carried out using a high-pressure homogenizer (5000 psi) to obtain the silymarin nanocarrier, which is the liquid to be sprayed;

[0059] S3 Finally, spray drying is carried out under the conditions of a temperature of 180 °C, a rotation speed of 20 rpm, and an atomization pressure of 0.2 MPa to obtain the silymarin spray-cured nanocarrier powder.

[0060] Example 4

[0061] S1 First, add 25 parts of silymarin, 20 parts of sunflower phospholipids, and 50 parts of span 80 to 200 ml of ethanol in sequence, and heat in a water bath at 50 °C to promote dissolution;

[0062] S2 Second, after the silymarin, sunflower phospholipids, and span 80 are completely dissolved, perform rotary evaporation at a temperature of 50 °C. After removing the organic solvent, add 500 ml of sodium alginate aqueous solution for hydration. After the substances in the eggplant-shaped flask are completely dissolved, homogenize with a high-pressure homogenizer (5000 psi) to prepare the silymarin nanocarrier, which is the liquid to be sprayed;

[0063] S3 Finally, perform spray drying under the conditions of a temperature of 180 °C, a rotation speed of 20 rpm, and an atomization pressure of 0.2 MPa to obtain the silymarin spray-cured nanocarrier powder.

[0064] Comparative Example 1

[0065] S1 First, add 25 parts of silymarin, 20 parts of sunflower phospholipids, and 50 parts of PVP K30 to 200 ml of ethanol in sequence, and heat in a water bath at 50 °C to promote dissolution;

[0066] S2 Second, after the silymarin, sunflower phospholipids, and PVP K30 are completely dissolved, perform rotary evaporation at a temperature of 50 °C. After removing the organic solvent, add 500 ml of sodium alginate aqueous solution for hydration. After the substances in the eggplant-shaped flask are completely dissolved, homogenize with a high-pressure homogenizer (5000 psi) to prepare the silymarin nanocarrier, which is the liquid to be sprayed;

[0067] S3 Finally, perform spray drying under the conditions of a temperature of 180 °C, a rotation speed of 20 rpm, and an atomization pressure of 0.2 MPa to obtain the silymarin spray-cured nanocarrier powder.

[0068] Comparative Example 2

[0069] S1 First, add 25 parts of silymarin, 20 parts of sunflower phospholipids, and 50 parts of tween 80 to 200 ml of ethanol in sequence, and heat in a water bath at 50 °C to promote dissolution;

[0070] S2 Second, after the silymarin, sunflower phospholipids, and tween 80 are completely dissolved, perform rotary evaporation at a temperature of 50 °C. After removing the organic solvent, add 500 ml of ultrapure water for hydration. After the substances in the eggplant-shaped flask are completely dissolved, homogenize with a high-pressure homogenizer (5000 psi) to prepare the silymarin nanocarrier, which is the liquid to be sprayed;

[0071] S3 Finally, perform spray drying under the conditions of a temperature of 180 °C, a rotation speed of 20 rpm, and an atomization pressure of 0.2 MPa to obtain the silymarin spray-cured nanocarrier powder.

[0072] Comparative Example 3

[0073] S1 First, add 25 parts of silymarin and 20 parts of sunflower phospholipids into 200 ml of ethanol in sequence, and heat in a water bath at 50 °C to promote dissolution;

[0074] S2 Second, after the silymarin and sunflower phospholipids are completely dissolved, perform rotary evaporation at a temperature of 50 °C. After removing the organic solvent, add 500 ml of sodium alginate ultrapure water for hydration. After the substances in the eggplant-shaped flask are completely dissolved, then homogenize with a high-pressure homogenizer (5000 psi) to obtain silymarin nanocarriers, which are the liquids to be sprayed;

[0075] S3 Finally, perform spray drying under the conditions of a temperature of 180 °C, a rotation speed of 20 rpm, and an atomization pressure of 0.2 MPa to obtain silymarin spray-cured nanocarrier powder.

[0076] Comparative Example 4

[0077] S1 First, add 25 parts of silymarin, 10 parts of sunflower phospholipids, 10 parts of soybean phospholipids, and 50 parts of PVPK30 into 200 ml of ethanol in sequence, and heat in a water bath at 50 °C to promote dissolution;

[0078] S2 Second, after the silymarin, sunflower phospholipids, soybean phospholipids, and PVPK30 are completely dissolved, perform rotary evaporation at a temperature of 50 °C. After removing the organic solvent, add 500 ml of sodium alginate aqueous solution for hydration. After the substances in the eggplant-shaped flask are completely dissolved, then homogenize with a high-pressure homogenizer (5000 psi) to obtain silymarin nanocarriers, which are the liquids to be sprayed;

[0079] S3 Finally, perform spray drying under the conditions of a temperature of 180 °C, a rotation speed of 20 rpm, and an atomization pressure of 0.2 MPa to obtain silymarin spray-cured nanocarrier powder.

[0080] Comparative Example 5

[0081] S1 First, add 25 parts of silymarin, 10 parts of sunflower phospholipids, and 50 parts of Tween 80 into 200 ml of ethanol in sequence, and heat in a water bath at 50 °C to promote dissolution;

[0082] S2 Second, after the silymarin, sunflower phospholipids, and Tween 80 are completely dissolved, perform rotary evaporation at a temperature of 50 °C. After removing the organic solvent, add 500 ml of sodium alginate aqueous solution for hydration. After the substances in the eggplant-shaped flask are completely dissolved, then homogenize with a high-pressure homogenizer (5000 psi) to obtain silymarin nanocarriers, which are the liquids to be sprayed;

[0083] Finally, spray drying was carried out under the conditions of a temperature of 180 °C, a rotation speed of 20 rpm, and an atomization pressure of 0.2 MPa to obtain the silymarin spray-cured nanocarrier powder.

[0084] Comparative Example 6

[0085] S1 First, 25 parts of silymarin, 20 parts of sunflower phospholipid, and 50 parts of Tween 80 were successively added to 200 ml of ethanol, and heated in a water bath at 50 °C to promote dissolution;

[0086] S2 Second, after silymarin, sunflower phospholipid, and Tween 80 were completely dissolved, rotary evaporation was carried out at a temperature of 50 °C. After removing the organic solvent, 500 ml of sodium alginate aqueous solution was added for hydration. After the substances in the eggplant-shaped flask were completely dissolved, homogenization was carried out with a high-pressure homogenizer (5000 psi) to prepare the silymarin nanocarrier;

[0087] S3 Finally, the nanocarrier was pre-frozen at -20 °C to -80 °C for 24 h, and the pre-frozen nanocarrier was placed in a freeze dryer and freeze-dried under vacuum conditions for 24 h, and dry powder was obtained by grinding.

[0088] Comparative Example 7

[0089] S1 First, 25 parts of silymarin, 20 parts of sunflower phospholipid, and 50 parts of Tween 80 were successively added to 200 ml of ethanol, and heated in a water bath at 50 °C to promote dissolution;

[0090] S2 Second, after silymarin, sunflower phospholipid, and Tween 80 were completely dissolved, rotary evaporation was carried out at a temperature of 50 °C. After removing the organic solvent, 500 ml of sodium alginate aqueous solution was added for hydration. After the substances in the eggplant-shaped flask were completely dissolved, homogenization was carried out with a high-pressure homogenizer (5000 psi) to prepare the silymarin nanocarrier, which was the liquid to be sprayed;

[0091] S3 Finally, spray drying was carried out under the conditions of a temperature of 100 °C, a rotation speed of 20 rpm, and an atomization pressure of 0.2 MPa to obtain a "viscous" substance.

[0092] Comparative Example 8

[0093] Silymarin raw material medicine.

[0094] Comparative Example 9

[0095] Commercially available silymarin liposomes.

[0096] Experimental Example 1 Study on the Physicochemical Properties of Silymarin Spray-Cured Nanocarrier Powder

[0097] The spray-cured nanocarrier powder prepared above was dissolved in ultrapure water and diluted to a 1 mg / ml solution. The particle size and polydispersity index (PDI) of the spray-cured nanocarrier powder in Examples 1-2 and Comparative Examples 4-5 were measured using a Malvern particle size analyzer. The measurement results are shown in Table 1.

[0098] Table 1 Particle size and PDI of silymarin spray-cured nanocarrier powder (n=3)

[0099] Example Particle size (nm) PDI Example 1 117.28±0.44 0.17±0.14 Example 2 109.62±0.52 0.18±0.05 Comparative Example 4 333.57±2.36 0.41±0.12 Comparative Example 5 286.35±3.41 0.38±0.48

[0100] As shown in Table 1, it can be seen that the particle size of Examples 1-2 is only about 100nm, and the PDI is less than 0.25, which proves that the spray-cured nanocarrier powder achieves good encapsulation of active substances, the particle distribution is uniform, it has a large specific surface area and a high surface energy, the system has good monodispersity, it is not easy to aggregate and settle, and a uniform and stable nanoparticle system is formed. The particle size and PDI of Comparative Example 4 are significantly increased, because PVP K30 can form a polymer layer on the surface of the nanocarrier, increase the steric hindrance, promote the aggregation of particles to reduce the surface energy, and then increase the particle size and PDI. Compared with Examples 1-2, the particle size and PDI of Comparative Example 5 are also significantly increased, indicating that a small amount of phospholipids cannot completely encapsulate silymarin, and the unencapsulated silymarin will act as a bridge to cause aggregation between nanocarriers. Silymarin molecules have certain polarity and chemical activity, and will interact with components such as phospholipids on the surface of nanocarriers, prompting multiple nanocarriers to adhere together to form aggregates of uneven size, which can lead to an increase in particle size and PDI.

[0101] Test Example 2 Effects of different drying methods and conditions on powder

[0102] The powder prepared in Example 1 is brown, uniform, fine dry powder.

[0103] The powder prepared in Comparative Example 6 is a brown-yellow, blocky substance, and needs to be ground to obtain nano-carrier powder. However, due to human factors during the grinding process, a very uniform powder cannot be obtained.

[0104] In Comparative Example 7, since the spray temperature is relatively low, the evaporation rate of the droplets is slowed down, resulting in the droplets not being completely dried before reaching the collector, thereby generating a "viscous" substance instead of a powdery substance.

[0105] It can be seen that the preparation process of Example 1 performs best in terms of powder state and uniformity, while Comparative Examples 6 and 7 have unsatisfactory powder states due to improper process parameters or subsequent treatments.

[0106] Experimental Example 3: Study on Solubilization Rate

[0107] Examples 1, 3, and 4 with excessive loading of the active ingredient, Comparative Examples 1-4, and Comparative Example 8 were added to ultrapure water. After shaking in a water bath and standing for 30 min for light-avoiding extraction, at the end of standing, ensure that the sample is filtered through a 0.22-μm filter membrane to obtain a clear supernatant. The solubility (P2) of the drug in the nanocarrier powder was measured using a UV spectrophotometer and the solubilization rate E was calculated, with the solubility of Comparative Example 8 being P1. E = P2 / P1. The results are shown in Table 2. Figure 1 Figure 2 shows the redissolution diagram of Example 1 and the dissolution diagram of Comparative Example 8 in ultrapure water, with the same mass of silymarin contained in both.

[0108] Table 2 Effects of different solubilizers and electrolytes on the solubilization rate

[0109] Example Solubilization rate Example 1 249 times Example 3 233 times Example 4 235 times Comparative Example 1 19 times Comparative Example 2 27 times Comparative Example 3 25 times Comparative Example 4 21 times

[0110] The results show that Example 1 has the best solubilization effect, with the dissolution rate increasing by 249 times. In Comparative Example 2, only the solubilizer is contained, and its solubilization rate is 9.2 times lower than that of Example 1. In Comparative Example 3, only the electrolyte is added, and its solubilization rate is approximately 10 times lower than that of Example 1. It is found that when the solubilizer and the electrolyte are added to the system simultaneously, the resulting solubilization effect is not a simple superposition, but shows a significant synergistic effect, enabling a qualitative leap in the solubilization rate and greatly enhancing the solubilization performance of the system. The solubilization rates of Examples 3-4 are relatively high as well, with almost no obvious difference from Example 1, further confirming the synergistic effect of the solubilizer and the electrolyte on the solubilization of silymarin. Although the solubilizer and the electrolyte were added simultaneously in Comparative Examples 1 and 4, the solubilization rates were very low, indicating that PVPK30 has an insignificant solubilization effect on silymarin and cannot effectively improve the dissolution degree of silymarin, and its performance in solubilization is relatively limited. From this, it can be known that the solubilizer and the electrolyte in the present invention are necessary, and Tween 80 and sodium alginate are most preferably used.

[0111] Test Example Four Stability Test

[0112] The silymarin spray-cured nanocarrier powders of Examples 1, 3, 4 and Comparative Examples 1, 2, 6 were each taken 5 g and sealed well, and placed in an oven (60 ± 1 °C), at room temperature (25 ± 1 °C), and in a refrigerator (4 ± 1 °C) for 30 days, respectively. The appearance states were observed for phenomena such as mildew, discoloration, and caking. The results are shown in Table 3.

[0113] Table 3 Results of the stability test

[0114] Example Initial state Oven (60 ± 1°C) Room temperature (25 ± 1°C) Refrigerator (4 ± 1°C) Example 1 Uniform powder No change No change No change Example 3 Uniform powder No change No change No change Example 4 Uniform powder No change No change No change Comparative Example 1 Uniform powder Color becomes lighter No change No change Comparative Example 6 Uniform powder No change 20% caking 20% caking

[0115] The results showed that the spray-cured nano-carrier powders prepared in Examples 1, 3, and 4 had very good stability, and their state would not be affected by external factors. After being placed for 30 days, there were no obvious changes in color, appearance, etc. However, the color of Comparative Example 1 became lighter after being placed in the oven for 30 days, but there was no change when placed at room temperature and in the refrigerator, indicating that high temperature would have an impact on Comparative Example 1. There was a caking phenomenon in Comparative Example 6 when placed at room temperature and in the refrigerator, indicating that they would absorb moisture and thus cake, and they were unstable when placed at low temperature.

[0116] Test Example Five SEM Observation of Silymarin

[0117] The microscopic morphology of the powder was observed using a scanning electron microscope (SEM), and it could be seen that Figure 2 in Comparative Example 8, an irregular particle morphology was presented, and the particle size distribution was relatively dispersed. Figure 3 in Example 1, spherical aggregates were shown, further confirming that silymarin was encapsulated in the nano-carrier, and there were many voids between the spheres, increasing the specific surface area, thus increasing the contact area between the spray-cured nano-carrier powder and water, promoting the dissolution process, and ultimately leading to enhanced water solubility.

[0118] Test Example Six Dissolution Test

[0119] In this test, the basket method was used for determination. A dissolution apparatus was used in this study, and the temperature was 37 ± 0.5 °C. An excessive amount of spray-cured nano-carrier powder of silymarin (Example 1), silymarin raw material drug (Comparative Example 8), and commercially available silymarin liposome (Comparative Example 9) were placed in the basket at a paddle speed of 250 rpm, and 500 ml of ultrapure water with a pH of 6.8 was used as the dissolution medium. At 10, 20, 30, 60, 90, 120, 150, 180, 210, and 240 min, 2 mL of the solution was respectively drawn from the container and passed through a 0.22 μm filter membrane. Then, an equal volume of temperature-equilibrated medium was added to the container. The filtered release content was diluted and analyzed using a UV spectrophotometer at 288 nm, and the cumulative release amount of silymarin was calculated (n = 3).

[0120] It can be seen from Figure 4 that there was almost no difference in the cumulative release amounts of Comparative Example 8 and Comparative Example 9 within 4 hours, and both were lower than 2%, with a very low release amount. However, the cumulative release amount of Example 1 rapidly increased to nearly 100% in about 0.5 hour, and then basically remained above 95% within 0.5 - 4 hours. The cumulative release amount increased by about 63 times, indicating that the spray-cured nano-carrier powder of silymarin could rapidly release after the start of the test and the release was relatively complete. By comparing three different forms of silymarin, it can be concluded that Example 1 showed a faster release rate and a more complete dissolution characteristic compared to Comparative Example 8 and Comparative Example 9, which was helpful for the drug to dissolve and be absorbed faster in the body.

[0121] Experimental Example VII: Pharmacokinetic Experiment

[0122] The spray-cured nanocarrier powder prepared in Example 1, the silymarin raw material drug of Comparative Example 8, and the commercially available silymarin liposome of Comparative Example 9 were subjected to a pharmacokinetic experiment: Rats with an average body weight of 180 - 240 g were used. The animals were starved for 12 hours before the experiment. The animals were randomly divided into 4 groups (n = 6). The first three groups were administered orally, while the fourth group was administered by intravenous injection. Comparative Example 8, Comparative Example 9, and Example 1 were assigned to the first group, the second group, and the third group, respectively. The fourth group received Example 1 via the intravenous injection route. The dosing dose for the first three groups was 20 mg / kg body weight, and the dosing dose for the fourth group was 2 mg / kg body weight. At specific time points after dosing, blood samples (0.3 mL) were collected from the orbital vein and then transferred to heparinized tubes for storage to ensure the anticoagulant effect of the blood samples. The blood samples were centrifuged at 3000 rpm for 5 minutes to separate the plasma. The silymarin content in the rat plasma was measured. The parameters after intravenous injection and oral administration of silymarin were calculated by the software DAS 2.0.

[0123] As Figure 5 and Figure 6 shown, the oral absorption of Comparative Example 8 was poor because of its poor solubility and permeability. After oral administration of Example 1, the peak blood drug concentration and the area under the curve increased. Compared with Comparative Example 8, the C max and AUC of Comparative Example 9 increased by 210 times and 114 times, respectively, while the C max and AUC of Example 1 increased by 464 times and 143 times, respectively. The absolute bioavailability of Example 1 was 34.30%, while the absolute bioavailabilities of Comparative Example 8 and Comparative Example 9 were 0.24% and 27.48%, respectively, indicating that the spray-cured nanocarrier powder of silymarin significantly improved the bioavailability of silymarin.

[0124] In summary, all the effects of the spray-cured nanocarrier powder of silymarin prepared in the present invention have been significantly improved. The solubilizer and electrolyte are synchronously introduced into the system innovatively, realizing a significant optimization of the solubilization effect, greatly improving the bioavailability, and making the nanocarrier into a powder state to optimize the system stability to the best state.

[0125] Although the embodiments of the present invention are disclosed for illustrative purposes, those skilled in the art can understand that: various substitutions, changes, and modifications are possible without departing from the spirit and scope of the present invention and the appended claims. Therefore, the scope of the present invention is not limited to the content disclosed in the embodiments.

Claims

1. A silymarin spray-cured nanocarrier powder, characterized in that: The invention comprises the following components in parts by weight: 5-40 parts of silymarin, 12-60 parts of phospholipids, 0.5-70 parts of solubilizers and 0.01-9 parts of electrolytes.

2. The silymarin spray-cured nano-carrier powder according to claim 1, characterized in that: The phospholipids are selected from one or more of the following components: sunflower lecithin, soybean lecithin, egg yolk lecithin, glycerophospholipids, diphosphatidylglycerol, dipalmitoylphosphatidylcholine, distearoylphosphatidylethanolamine-polyethylene glycol, cephalin, dimyristoylphosphatidylcholine, dipalmitoylphosphatidylethanolamine, and hydrogenated soybean lecithin.

3. The silymarin spray-cured nano-carrier powder according to claim 1, characterized in that: The solubilizing agent is selected from one or more of the following components: cationic surfactant, anionic surfactant, nonionic surfactant, cyclodextrin and its derivatives, and polyethylene glycol.

4. The silymarin spray-cured nano-carrier powder according to claim 1, characterized in that: The electrolyte is a substance that can dissociate into cations and anions in water, and is selected from one or more of the following components: sodium bicarbonate, sodium citrate, sodium alginate, calcium chloride, sodium carboxymethyl cellulose, potassium nitrate, and sodium dihydrogen phosphate.

5. The method for preparing the silymarin spray-cured nano-carrier powder according to any one of claims 1 to 4, characterized in that , including the following steps: (1) adding silymarin, phospholipid and fat-soluble solubilizing agent into an organic solvent in sequence and fully dissolving them; (2) removing the organic solvent and replacing it with an aqueous electrolyte solution containing a water-soluble solubilizer; (3) spray drying to obtain silymarin spray-cured nano-carrier powder.

6. The method for preparing the silymarin spray-cured nano-carrier powder according to claim 5, characterized in that: In step (1), sufficient dissolution is achieved by heating the raw materials and auxiliary materials in a water bath at 40-80°C to promote dissolution.

7. The method for preparing the silymarin spray-cured nano-carrier powder according to claim 5, characterized in that: In step (2), the method for removing the organic solvent is selected from one of the following methods: rotary evaporation, vacuum drying, and natural volatilization.

8. The method for preparing the silymarin spray-cured nano-carrier powder according to claim 5, characterized in that: The conditions for spray drying in step (3) are: spray temperature of 110-200° C., rotation speed of 5-30 rpm, and atomization pressure of 0.1-0.4 MPa.

9. The method for preparing the silymarin spray-cured nano-carrier powder according to claim 5, characterized in that: In step (3), the particle size of the spray-cured nanocarrier powder after redissolving in water is 10-200 nm.

10. Use of the silymarin spray-cured nano-carrier powder according to any one of claims 1 to 9 in food, health products, skin care products, medical devices and medicines.

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