Preparation method of triptolide hydrogel microneedle

Abstract

The invention provides a preparation method of a triptolide hydrogel microneedle, and particularly relates to the technical field of hydrogel microneedles. According to the method, an O / W type triptolide microemulsion is obtained through a microemulsion method so as to solve the problem of hydrophobicity of triptolide, and hyaluronic acid, deionized water and the O / W type triptolide microemulsion are combined in proportion in a specific mode so as to solve the demulsification problem of the O / W type triptolide microemulsion. Therefore, the triptolide hydrogel microneedle capable of controllably releasing the effective components of the tripterygium wilfordii is prepared. The method solves the problem of hydrophobicity of triptolide and the problem of demulsification of O / W type triptolide microemulsion, so that controllable release of effective components of tripterygium wilfordii is realized, the permeability and utilization rate of drugs are improved, and a new method and approach are provided for traditional Chinese medicine treatment of RA.

Description

Technical Field

[0001] The invention relates to the technical field of hydrogel microneedles, and in particular to a method for preparing triptolide hydrogel microneedles. Background Art

[0002] Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease characterized by persistent synovitis caused by excessive release of inflammatory cytokines, mainly affecting joints and surrounding soft tissues. The global incidence of RA is about 0.5%-1%, and about 0.42% in my country, with a total number of patients reaching 5 million. According to statistics, RA is one of the most important disabling diseases in my country, with a disability rate of up to 61.3%. Disability is a high-probability event that long-term RA patients will encounter. It is often referred to as "immortal cancer". Generally, long-term medication and monitoring of inflammatory indicators are required to determine the disease activity and treatment status to prevent further damage to bones by the disease. Therefore, timely and accurate diagnosis and treatment of RA not only involves the life, health and living standards of the people, but is also closely related to the continuous progress of the economy and society. Triptergium wilfordii Hook.F (TwHF) is a deciduous shrub of the Celastraceae family. Its core medicinal part is the xylem of its roots. Because of its strong effects of dispelling wind and dampness and promoting blood circulation and unblocking collaterals, it is often used clinically to treat RA.

[0003] There are two main ways to use Tripterygium wilfordii to treat RA. One is to administer the drug orally. However, traditional oral preparations are prone to cause adverse reactions in the digestive system and urogenital system, with an incidence of 35.8% and 22.8% respectively, which seriously affects the clinical application of Tripterygium wilfordii drugs. Chinese medicine also believes that long-term medication will hinder the spleen and stomach from transporting and transforming, resulting in the loss of vital energy, and often with half the result with twice the effort. Therefore, the development of external preparations of Tripterygium wilfordii can avoid the "first-pass effect" in order to increase efficacy and reduce toxicity. Another method is to use the decoction of Tripterygium wilfordii roots for washing or external application as a powder. With the continuous advancement of pharmaceutical technology, a variety of transdermal drug administration methods have been gradually developed, including tinctures, ointments, cataplasms, plasters, liniments, film coatings and nano preparations. These traditional external preparations reduce oral hepatorenal toxicity and have significant analgesic effects compared to oral preparations, but due to the presence of the stratum corneum, the transdermal permeability of the drug is low and the utilization rate is not high. In recent years, microneedles (MN) as a new transdermal drug delivery technology have been widely used in the fields of insulin delivery, vaccines, anesthesia, medical cosmetology, etc., and have also been used in the detection of biomarkers in skin interstitial fluid and chronic disease management such as blood glucose monitoring. Although the combination of Tripterygium wilfordii and microneedle technology provides a solution to the problem of low transdermal permeability and low utilization rate of drugs, triptolide is hydrophobic, and in the process of preparing triptolide hydrogel microneedle precursor solution, O / W type triptolide microemulsion has demulsification problems, which makes it impossible to solve the problem of low transdermal permeability and low utilization rate of the active ingredients of Tripterygium wilfordii through microneedle technology.

[0004] In summary, how to solve the hydrophobicity problem of triptolide and the demulsification problem of O / W type triptolide microemulsion, so as to achieve the controlled release of the active ingredients of triptolide and improve the permeability and utilization of the drug is a difficult problem that needs to be overcome urgently in this technical field. Summary of the invention

[0005] The main purpose of the present invention is to provide a method for preparing triptolide hydrogel microneedles to solve the hydrophobicity problem of triptolide and the demulsification problem of O / W type triptolide microemulsion, thereby achieving the controlled release of the effective ingredients of triptolide, improving the permeability and utilization rate of the drug, and further providing a new method and approach for the traditional Chinese medicine treatment of RA.

[0006] In order to achieve the above objectives, the present invention provides a method for preparing triptolide hydrogel microneedles, thereby achieving controlled release of the effective ingredients of triptolide, improving the permeability and utilization of the drug, and further providing a new method and approach for the traditional Chinese medicine treatment of RA.

[0007] The present invention provides a method for preparing a triptolide hydrogel microneedle, the method comprising:

[0008] Obtaining an O / W type triptolide microemulsion by a microemulsion method, wherein the microemulsion method is used to solve the hydrophobicity problem of triptolide;

[0009] Obtaining hyaluronic acid and deionized water, wherein the hyaluronic acid is used to combine with the O / W type triptolide microemulsion to prepare triptolide hydrogel microneedles;

[0010] The hyaluronic acid, the deionized water and the O / W type triptolide microemulsion are combined to obtain triptolide hydrogel microneedles.

[0011] Optionally, the O / W type triptolide microemulsion is obtained by a microemulsion method, comprising:

[0012] Obtaining a triptolide microemulsion preparation material, wherein the triptolide microemulsion preparation material comprises: an emulsifier, an oil phase, an emulsifier aid, triptolide and deionized water;

[0013] preparing a triptolide alcohol solution according to the co-emulsifier and the triptolide;

[0014] preparing a triptolide mixed emulsifier according to the emulsifier and the triptolide alcohol solution;

[0015] The O / W type triptolide microemulsion is obtained according to the oil phase, the deionized water and the triptolide mixed emulsifier.

[0016] Optionally, the emulsifier is determined to be Tween 80; the oil phase is determined to be ethyl butyrate; and the co-emulsifier is determined to be anhydrous ethanol.

[0017] Optionally, the preparation of the triptolide alcohol solution according to the co-emulsifier and the triptolide comprises:

[0018] The triptolide with a mass of W mg is dissolved in the anhydrous ethanol with a volume of V ml to obtain the triptolide alcohol solution, wherein:

[0019] 1.800mg / mL≤W / V≤2.212mg / mL.

[0020] Optionally, the preparation of a triptolide mixed emulsifier according to the emulsifier and the triptolide alcohol solution comprises:

[0021] The mass of the anhydrous ethanol in the triptolide alcohol solution is obtained to be M mg;

[0022] Add K mg of Tween 80 into the triptolide alcohol solution and stir evenly to obtain the triptolide mixed emulsifier, wherein 0.25≤K / M≤2.

[0023] Optionally, the O / W type triptolide microemulsion is obtained by mixing the oil phase, the deionized water and the triptolide emulsifier, comprising:

[0024] Add D mg of the ethyl butyrate into a beaker containing Q mg of the deionized water;

[0025] The beaker is placed on a magnetic stirrer and stirred at a uniform speed while the triptolide mixed emulsifier is gradually added dropwise until the solution in the beaker becomes transparent and clear and the Tyndall phenomenon occurs, thereby obtaining an O / W type triptolide microemulsion, wherein 1 / 9≤D / Q≤1 / 4.

[0026] Optionally, the O / W type triptolide microemulsion formulation is: the mass of the ethyl butyrate accounts for 6.90%; the mass of the deionized water accounts for 62.07%; the mass of Tween 80 accounts for 6.21%; the mass of the anhydrous ethanol accounts for 24.76%; and the mass of the triptolide accounts for 0.06%.

[0027] Optionally, the combining of the hyaluronic acid, the deionized water and the O / W type triptolide microemulsion to obtain the triptolide hydrogel microneedle comprises:

[0028] Completely dissolving the hyaluronic acid with the deionized water to obtain a hyaluronic acid solution;

[0029] The hyaluronic acid solution is mixed with the O / W type triptolide microemulsion to obtain the triptolide hydrogel microneedle.

[0030] Optionally, the mass of the hyaluronic acid in the triptolide hydrogel microneedle is T mg, and the volume of the O / W type triptolide microemulsion is L ml, wherein,

[0031] 150mg / mL≤T / L≤200mg / mL.

[0032] The present application provides a method for preparing a triptolide hydrogel microneedle, which obtains an O / W type triptolide microemulsion by a microemulsion method, wherein the microemulsion method is used to solve the hydrophobicity problem of triptolide; obtain hyaluronic acid and deionized water, wherein the hyaluronic acid is used to prepare a triptolide hydrogel microneedle in combination with the O / W type triptolide microemulsion; combine the hyaluronic acid, the deionized water and the O / W type triptolide microemulsion to obtain a triptolide hydrogel microneedle. This method solves the hydrophobicity problem of triptolide and the demulsification problem of the O / W type triptolide microemulsion, thereby achieving the controlled release of the effective ingredients of triptolide, improving the permeability and utilization rate of the drug, and thus providing a new method and approach for the traditional Chinese medicine treatment of RA. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0034] Figure 1 A schematic diagram of the process for preparing the triptolide hydrogel microneedle provided in this application;

[0035] Figure 2 An optical microscope image of the hollow microneedle of the triptolide hydrogel microneedle provided in this application;

[0036] Figure 3 An optical microscope image of a solid microneedle of the triptolide hydrogel microneedle provided in this application;

[0037] Figure 4 The SEM image of the triptolide hydrogel microneedle provided in this application;

[0038] The above drawings have shown clear embodiments of the present application, which will be described in more detail later. These drawings and text descriptions are not intended to limit the scope of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solutions and advantages of this application clearer, the technical solutions in this application will be clearly and completely described below in conjunction with the drawings in this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0040] In the present invention, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in this application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.

[0041] Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease characterized by persistent synovitis caused by excessive release of inflammatory cytokines, mainly affecting joints and surrounding soft tissues. The global incidence of RA is about 0.5%-1%, and about 0.42% in my country, with a total number of patients reaching 5 million. According to statistics, RA is one of the most important disabling diseases in my country, with a disability rate of up to 61.3%. Disability is a high-probability event that long-term RA patients will encounter. It is often referred to as "immortal cancer". Generally, long-term medication and monitoring of inflammatory indicators are required to determine the disease activity and treatment status to prevent further damage to bones by the disease. Therefore, timely and accurate diagnosis and treatment of RA not only involves the life, health and living standards of the people, but is also closely related to the continuous progress of the economy and society. Triptergium wilfordii Hook.F (TwHF) is a deciduous shrub of the Celastraceae family. Its core medicinal part is the xylem of its roots. Because of its strong effects of dispelling wind and dampness and promoting blood circulation and unblocking collaterals, it is often used clinically to treat RA.

[0042] There are two main ways to use Tripterygium wilfordii to treat RA. One is to administer the drug orally. However, traditional oral preparations are prone to cause adverse reactions in the digestive system and urogenital system, with an incidence of 35.8% and 22.8% respectively, which seriously affects the clinical application of Tripterygium wilfordii drugs. Chinese medicine also believes that long-term medication will hinder the spleen and stomach from transporting and transforming, resulting in the loss of vital energy, and often with half the result with twice the effort. Therefore, the development of external preparations of Tripterygium wilfordii can avoid the "first-pass effect" in order to increase efficacy and reduce toxicity. Another method is to use the decoction of Tripterygium wilfordii roots for washing or external application as a powder. With the continuous advancement of pharmaceutical technology, a variety of transdermal drug administration methods have been gradually developed, including tinctures, ointments, cataplasms, plasters, liniments, film coatings and nano preparations. These traditional external preparations reduce oral hepatorenal toxicity and have significant analgesic effects compared to oral preparations, but due to the presence of the stratum corneum, the transdermal permeability of the drug is low and the utilization rate is not high. In recent years, microneedles (MN) as a new transdermal drug delivery technology have been widely used in the fields of insulin delivery, vaccines, anesthesia, medical cosmetology, etc., and have also been used in the detection of biomarkers in skin interstitial fluid and chronic disease management such as blood glucose monitoring. Although the combination of Tripterygium wilfordii and microneedle technology provides a solution to the problem of low transdermal permeability and low utilization rate of drugs, triptolide is hydrophobic, and in the process of preparing triptolide hydrogel microneedle precursor solution, O / W type triptolide microemulsion has demulsification problems, which makes it impossible to solve the problem of low transdermal permeability and low utilization rate of the active ingredients of Tripterygium wilfordii through microneedle technology.

[0043] In summary, how to solve the hydrophobicity problem of triptolide and the demulsification problem of O / W type triptolide microemulsion, so as to achieve the controlled release of the active ingredients of triptolide and improve the permeability and utilization of the drug is a difficult problem that needs to be overcome urgently in this technical field.

[0044] In view of the above problems, the present application provides a method for preparing a triptolide hydrogel microneedle, which obtains an O / W type triptolide microemulsion by a microemulsion method, wherein the microemulsion method is used to solve the hydrophobicity problem of triptolide; obtain hyaluronic acid and deionized water, wherein the hyaluronic acid is used to prepare a triptolide hydrogel microneedle in combination with the O / W type triptolide microemulsion; combine the hyaluronic acid, the deionized water and the O / W type triptolide microemulsion to obtain a triptolide hydrogel microneedle. This method solves the hydrophobicity problem of triptolide and the demulsification problem of the O / W type triptolide microemulsion, thereby achieving the controlled release of the effective ingredients of triptolide, improving the permeability and utilization rate of the drug, and thus providing a new method and approach for the traditional Chinese medicine treatment of RA.

[0045] The technical solution of the present application and how the technical solution of the present application solves the above-mentioned technical problems are described in detail below with specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0046] Figure 1 The schematic diagram of the process of preparing the triptolide hydrogel microneedle provided in the present application describes the preparation method of the triptolide hydrogel microneedle in detail, such as Figure 1 As shown, the preparation method of triptolide hydrogel microneedle provided in this embodiment comprises:

[0047] S101: Obtaining an O / W type triptolide microemulsion by a microemulsion method.

[0048] Among them, the microemulsion method, also known as the reverse micelle method, is a liquid phase chemical method for preparing nanomaterials. The core of this method is to use two immiscible solvents to form an emulsion under the action of a surfactant, that is, the amphiphilic molecules divide the continuous medium into tiny spaces to form a microreactor, in which the reactants react to form a solid phase. The microemulsion method is used to solve the problem of the hydrophobicity of triptolide;

[0049] Specifically, the method of obtaining an O / W type triptolide microemulsion by a microemulsion method comprises:

[0050] Obtaining a triptolide microemulsion preparation material, wherein the triptolide microemulsion preparation material comprises: an emulsifier, an oil phase, an emulsifier aid, triptolide and deionized water;

[0051] preparing a triptolide alcohol solution according to the co-emulsifier and the triptolide;

[0052] preparing a triptolide mixed emulsifier according to the emulsifier and the triptolide alcohol solution;

[0053] The O / W type triptolide microemulsion is obtained according to the oil phase, the deionized water and the triptolide mixed emulsifier.

[0054] Furthermore, the emulsifier can be Tween 80, Tween 20, or Tween 40 with an HLB value between 8 and 18; the oil phase can be ethyl butyrate, isopropyl myristate, or oleic acid; the co-emulsifier can be anhydrous ethanol or isopropanol; preferably, the emulsifier is determined to be Tween 80; the oil phase is determined to be ethyl butyrate; and the co-emulsifier is determined to be anhydrous ethanol.

[0055] Furthermore, the preparation of the triptolide alcohol solution according to the co-emulsifier and the triptolide comprises:

[0056] The triptolide with a mass of W mg is dissolved in the anhydrous ethanol with a volume of V ml to obtain the triptolide alcohol solution, wherein:

[0057] 1.800 mg / mL≤W / V≤2.212 mg / mL. After a large number of tests, when the W / V value is 1.800 mg / mL or 2.212 mg / mL, a triptolide alcohol solution that meets the test requirements can be produced. Preferably, the W / V value can be 2.000 mg / mL.

[0058] Furthermore, the preparation of a triptolide mixed emulsifier according to the emulsifier and the triptolide alcohol solution comprises:

[0059] The mass of the anhydrous ethanol in the triptolide alcohol solution is obtained to be M mg;

[0060] Add K mg of Tween 80 to the triptolide alcohol solution and stir evenly to obtain the triptolide mixed emulsifier, wherein 0.25≤K / M≤2. After a large number of experiments, a triptolide mixed emulsifier that meets the test requirements can be produced when the K / M value is 0.25 or 2. Preferably, the K / M value can be 0.25.

[0061] Furthermore, the O / W type triptolide microemulsion is obtained according to the oil phase, the deionized water and the triptolide mixed emulsifier, comprising:

[0062] Add D mg of the ethyl butyrate into a beaker containing Q mg of the deionized water;

[0063] The beaker is placed on a magnetic stirrer and stirred at a uniform speed, and the triptolide mixed emulsifier is gradually added dropwise until the solution in the beaker becomes transparent and clear and there is a Tyndall phenomenon, thereby obtaining an O / W type triptolide microemulsion, wherein 1 / 9≤D / Q≤1 / 4. After a large number of experiments, when the value of D / Q is 1 / 9 or 1 / 4, an O / W type triptolide microemulsion that meets the experimental requirements can be prepared.

[0064] Preferably, the O / W type triptolide microemulsion formulation is: the mass proportion of the ethyl butyrate is 6.90%; the mass proportion of the deionized water is 62.07%; the mass proportion of Tween 80 is 6.21%; the mass proportion of the anhydrous ethanol is 24.76%; and the mass proportion of triptolide is 0.06%.

[0065] It is understandable that the preparation of O / W type triptolide microemulsion solves the hydrophobicity problem of triptolide. The oil droplets in the microemulsion are small and uniform, which can significantly increase the solubility of triptolide in water, thereby improving its bioavailability. At the same time, the presence of the emulsifier can stabilize the microemulsion system, prevent the aggregation and precipitation of the oil droplets, and ensure that triptolide can be stably released in vivo and exert its efficacy. In addition, the preparation of O / W type triptolide microemulsion may also bring other advantages. For example, by adjusting the type and concentration of the emulsifier, the parameters such as the particle size, stability and drug release rate of the microemulsion can be further controlled, thereby achieving precise regulation of the pharmacokinetics and pharmacodynamics of triptolide. This helps to reduce the toxic and side effects of the drug, improve the therapeutic effect, and provide strong support for its wide clinical application. In summary, the preparation of O / W type triptolide microemulsion not only solves the hydrophobicity problem of triptolide, but also opens up new ways for its clinical transformation and application. This achievement is a model for the application of nanotechnology in the field of traditional Chinese herbal medicine, demonstrating the broad prospects for the combination of modern technology and traditional medicine.

[0066] S102: Obtain hyaluronic acid and deionized water.

[0067] Among them, hyaluronic acid, also known as hyaluronic acid or hyaluronic acid, is an acidic mucopolysaccharide with a chemical formula of (CHNO)n, a disaccharide unit glycosaminoglycan composed of D-glucuronic acid and N-acetylglucosamine. The hyaluronic acid is used to prepare the triptolide hydrogel microneedle in combination with the O / W type triptolide microemulsion. Deionized water refers to pure water after the impurities in ionic form are removed. Deionized water is used to dissolve hyaluronic acid. The acquisition of hyaluronic acid and deionized water can be obtained through conventional experiments or by purchase. The specific acquisition method is determined according to actual needs and is not limited here.

[0068] S103: combining the hyaluronic acid, the deionized water and the O / W type triptolide microemulsion to obtain triptolide hydrogel microneedles.

[0069] Furthermore, the step of combining the hyaluronic acid, the deionized water and the O / W type triptolide microemulsion to obtain the triptolide hydrogel microneedle comprises:

[0070] Completely dissolving the hyaluronic acid with the deionized water to obtain a hyaluronic acid solution;

[0071] The hyaluronic acid solution is mixed with the O / W type triptolide microemulsion to obtain the triptolide hydrogel microneedle.

[0072] Furthermore, the mass of the hyaluronic acid in the triptolide hydrogel microneedle is T mg, and the volume of the O / W type triptolide microemulsion is L ml, wherein:

[0073] 150mg / mL≤T / L≤200mg / mL. After a large number of experiments, when the T / L value is 150mg / mL or 200mg / mL, a triptolide hydrogel microneedle can be prepared that can achieve controlled release of the active ingredients of triptolide and improve the permeability and utilization of the drug.

[0074] Preferably, the effect of triptolide hydrogel microneedle is best when the T / L value is 200 mg / mL.

[0075] The following steps can be referred to when implementing this embodiment:

[0076] Step 1: Preparation of O / W type triptolide microemulsion

[0077] The test shows that the solubility of triptolide in anhydrous ethanol is 2.212 mg / mL. Therefore, 20 mg of triptolide is dissolved in 10 mL of anhydrous ethanol to prepare a triptolide alcohol solution, and then a quantitative amount of Tween 80 is added according to Km=1:4 (Km refers to the mass ratio of Tween 80 to anhydrous ethanol), and the triptolide mixed emulsifier is obtained after stirring evenly. 1 g of ethyl butyrate is put into a beaker containing 9 g of deionized water, and then the beaker is placed on a magnetic stirrer and stirred at a uniform speed and the triptolide mixed emulsifier is gradually added dropwise until the solution becomes transparent and clear and has a Tyndall phenomenon, indicating that the triptolide microemulsion is successfully prepared. According to the determination method of microemulsion configuration, the prepared triptolide microemulsion is indeed O / W type. The O / W type triptolide microemulsion formula is as follows: ethyl butyrate 6.90% (mass); deionized water 62.07% (mass); Tween 806.21% (mass); anhydrous ethanol 24.76% (mass); triptolide 0.06% (mass). Among them, the determination of O / W type and W / O type triptolide microemulsion and the determination of blank microemulsion formula can be used to identify the configuration of triptolide microemulsion by dyeing method or dilution method. Dyeing method: Take 2 equal amounts of triptolide microemulsion, add 2 drops of water-soluble dye methylene blue and oil-soluble dye Sudan red respectively, observe the diffusion speed in each microemulsion to judge the configuration of the microemulsion, if Sudan red solution diffuses faster, the microemulsion is W / O type, if methylene blue solution diffuses faster, the microemulsion is O / W type. Dilution method: Take 2 equal parts of the emulsion and add a large amount of oil phase or water phase to dilute them. If the liquid remains clear and transparent after adding the oil phase, but becomes turbid after adding the water phase, it is W / O type; otherwise, it is O / W type.

[0078] Step 2: Two-step fusion method to solve the problem of microemulsion demulsification. The preparation method of triptolide hydrogel microneedle is as follows:

[0079] Hyaluronic acid (HA) is a highly hydrophilic hydrogel material, while triptolide is hydrophobic. In order to combine the two to prepare microneedles, we used the microemulsion method to prepare triptolide into a hydrophilic O / W type triptolide microemulsion. In the process of directly combining O / W type triptolide microemulsion with HA, we found that when the HA content exceeded 15%, too much water in the microemulsion was absorbed by HA and demulsification occurred, resulting in the separation of the drug solution from HA, and the drug content of the formed microneedles could not be detected; and when the HA content was too low, the mechanical strength of the microneedle was not enough to penetrate the skin. Therefore, we first completely dissolved HA with deionized water and then mixed it with the O / W type triptolide microemulsion, which can not only ensure the stability of the microemulsion, but also solve the problem of insufficient mechanical properties of the microneedle due to too low HA content. Using the above method, we tried to prepare 10%-20% triptolide hydrogel microneedles, and observed the filling and molding of the microneedles with an optical microscope. The results showed that when W / V was less than 20%, although the formation of the tripterygium wilfordii hydrogel microneedles was very good, the hollow rate was high. Finally, we determined the tripterygium wilfordii hydrogel microneedles with an HA content of 20% and successfully detected the drug content, where 20% refers to the ratio of the mass of the hyaluronic acid to the volume of the O / W type tripterygium wilfordii microemulsion, expressed in grams per milliliter.

[0080] like Figure 2 , Figure 3 , Figure 4 As shown, the optical microscope image shows that 20% of the Tripterygium wilfordii hydrogel microneedles have intact needle bodies and are fully filled. The microneedle forming rate is over 97%, and the needle body height is about 500μm, which is basically consistent with the metal microneedle positive mold data. Scanning electron microscope (SEM) images show that the microneedles have a complete quadrangular pyramid structure. The skin consists of the epidermis and dermis, with thicknesses of 76.9-267.4μm and 2115-5888μm, respectively. The results show that the prepared microneedles are long enough to penetrate the epidermis and reach the dermis, and release the drug through the dissolution of the needle body under the skin. Moreover, due to the limited length of the needle body, it will not touch the blood vessels and nerves deep in the dermis, so it will not cause bleeding and pain.

[0081] For reference, the embodiment also provides the screening of emulsifiers, the screening of oil phases, the screening of co-emulsifiers, and the screening of Km values ​​(Km refers to the mass ratio of Tween 80 to anhydrous ethanol):

[0082] 1.1 Emulsifier selection

[0083] The experiment showed that the stronger the fluidity of the surfactant, the easier it is to form microemulsions. O / W microemulsions can be formed when the HLB value is between 8 and 18. Therefore, we selected Tween 80, Tween 20, and Tween 40 with HLB values ​​between 8 and 18 as the screening targets for emulsifiers. A single-factor experimental design was adopted, with ethyl butyrate as the fixed oil phase, anhydrous ethanol as the auxiliary emulsifier, and Km=2:1. Microemulsions were prepared using Tween 80, Tween 20, and Tween 40 as emulsifiers. By comparing the ME areas formed by the three emulsifiers, we found that when Tween 80 was used as an emulsifier, the mixed emulsifier had the best emulsification effect, was easier to form microemulsions, and had a relatively high water content. Therefore, Tween 80 was selected as the emulsifier for the blank microemulsion. The ME area is used to reflect the diversity or difficulty of the component combination that can form a stable microemulsion under certain conditions. Specifically, in microemulsion research, the pseudo-ternary phase diagram is a commonly used tool to represent the phase behavior of each component (emulsifier, co-emulsifier, oil phase, water phase) in the microemulsion system at different proportions. The ME region (Microemulsion Region) in the figure represents the range of component proportions that can form microemulsions. Therefore, the size of the ME area directly reflects the diversity or difficulty of the combination of components that can form stable microemulsions under certain conditions.

[0084] 1.2 Screening of oil phase

[0085] According to the results of emulsifier screening, the fixed emulsifier is Tween 80, the auxiliary emulsifier is anhydrous ethanol, Km=2:1, and ethyl butyrate, isopropyl myristate, and oleic acid are used as oil phases to prepare microemulsions. By comparing the area of ​​the microemulsion region (ME) formed by the three oil phases, we found that when ethyl butyrate is the oil phase, the emulsification effect is the best, it is easier to form microemulsions, and the water content is relatively high, so ethyl butyrate is selected as the oil phase of the blank microemulsion.

[0086] 1.3 Screening of emulsifier

[0087] According to the results of the previous screening of emulsifiers and oil phases, the fixed oil phase is ethyl butyrate, the emulsifier is Tween 80, Km=2:1, and anhydrous ethanol and isopropanol are used as co-emulsifiers to prepare microemulsions. By comparing the ME areas formed by the two co-emulsifiers, we found that when anhydrous ethanol is used as the co-emulsifier, the emulsification effect of the mixed emulsifier is the best and it is easier to form microemulsions. Therefore, anhydrous ethanol is selected as the co-emulsifier of the blank microemulsion.

[0088] 1.4Km value screening

[0089] According to the results of the previous screening of emulsifiers, oil phases and co-emulsifiers, the fixed emulsifier is Tween 80, the oil phase is ethyl butyrate, the co-emulsifier is anhydrous ethanol, and the Km is 2:1, 1:1, 1:2, and 1:4 to prepare microemulsions. By comparing the ME areas formed by several Km values, we found that the ME areas formed by several Km values ​​are not much different, that is, the emulsification effect is basically the same. Considering that in the preparation process of triptolide microemulsion, triptolide is first dissolved in anhydrous ethanol, which means that the content of triptolide in the microemulsion is proportional to the ethanol content. In order to increase the content of triptolide in the microemulsion, we selected Km=1:4 as the Km value of the blank microemulsion.

[0090] The present application provides a method for preparing a triptolide hydrogel microneedle, which obtains an O / W type triptolide microemulsion by a microemulsion method, wherein the microemulsion method is used to solve the hydrophobicity problem of triptolide; obtain hyaluronic acid and deionized water, wherein the hyaluronic acid is used to prepare a triptolide hydrogel microneedle in combination with the O / W type triptolide microemulsion; combine the hyaluronic acid, the deionized water and the O / W type triptolide microemulsion to obtain a triptolide hydrogel microneedle. This method solves the hydrophobicity problem of triptolide and the demulsification problem of the O / W type triptolide microemulsion, thereby achieving the controlled release of the effective ingredients of triptolide, improving the permeability and utilization rate of the drug, and thus providing a new method and approach for the traditional Chinese medicine treatment of RA.

[0091] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the invention disclosed herein. The present application is intended to cover any modification, use or adaptation of the present application, which follows the general principles of the present application and includes common knowledge or customary techniques in the art that are not disclosed in the present application. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present application are indicated by the following claims.

[0092] It should be understood that the present application is not limited to the precise structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A method for preparing triptolide hydrogel microneedles, characterized in that: The method comprises: obtaining an O / W type triptolide microemulsion by a microemulsion method; Obtain hyaluronic acid and deionized water; The hyaluronic acid, the deionized water and the O / W type triptolide microemulsion are combined to obtain triptolide hydrogel microneedles.

2. The method according to claim 1, characterized in that The method of obtaining an O / W type triptolide microemulsion by a microemulsion method comprises: Obtaining a triptolide microemulsion preparation material, wherein the triptolide microemulsion preparation material comprises: an emulsifier, an oil phase, an emulsifier aid, triptolide and deionized water; preparing a triptolide alcohol solution according to the co-emulsifier and the triptolide; preparing a triptolide mixed emulsifier according to the emulsifier and the triptolide alcohol solution; The O / W type triptolide microemulsion is obtained according to the oil phase, the deionized water and the triptolide mixed emulsifier.

3. The method according to claim 2, characterized in that The emulsifier is determined to be Tween 80; the oil phase is determined to be ethyl butyrate; and the co-emulsifier is determined to be anhydrous ethanol.

4. The method according to claim 3, characterized in that The method for preparing the triptolide alcohol solution according to the co-emulsifier and the triptolide comprises: The triptolide with a mass of W mg is dissolved in the anhydrous ethanol with a volume of V ml to obtain the triptolide alcohol solution, wherein: 1.800mg / mL≤W / V≤2.212mg / mL.

5. The method according to claim 4, characterized in that The method for preparing a triptolide mixed emulsifier according to the emulsifier and the triptolide alcohol solution comprises: The mass of the anhydrous ethanol in the triptolide alcohol solution is obtained to be M mg; Add K mg of Tween 80 into the triptolide alcohol solution and stir evenly to obtain the triptolide mixed emulsifier, wherein 0.25≤K / M≤2.

6. The method according to claim 5, characterized in that The method of obtaining the O / W type triptolide microemulsion according to the oil phase, the deionized water and the triptolide mixed emulsifier comprises: Add D mg of the ethyl butyrate into a beaker containing Q mg of the deionized water; The beaker is placed on a magnetic stirrer and stirred at a uniform speed while the triptolide mixed emulsifier is gradually added dropwise until the solution in the beaker becomes transparent and clear and the Tyndall phenomenon occurs, thereby obtaining an O / W type triptolide microemulsion, wherein 1 / 9≤D / Q≤1 / 4.

7. The method according to claim 3, characterized in that The O / W type triptolide microemulsion formula is: the mass of the ethyl butyrate accounts for 6.90%; the mass of the deionized water accounts for 62.07%; the mass of Tween 80 accounts for 6.21%; the mass of the anhydrous ethanol accounts for 24.76%; and the mass of the triptolide accounts for 0.06%.

8. The method according to claim 1, characterized in that The step of combining the hyaluronic acid, the deionized water and the O / W type triptolide microemulsion to obtain the triptolide hydrogel microneedle comprises: Completely dissolving the hyaluronic acid with the deionized water to obtain a hyaluronic acid solution; The hyaluronic acid solution is mixed with the O / W type triptolide microemulsion to obtain the triptolide hydrogel microneedle.

9. The method according to claim 8, characterized in that The mass of the hyaluronic acid in the triptolide hydrogel microneedle is T mg, and the volume of the O / W type triptolide microemulsion is L ml, wherein 150 mg / mL≤T / L≤200 mg / mL.

Images