Soluble microneedle patch for hair growth as well as preparation method and application of soluble microneedle patch

Abstract

The invention relates to a soluble microneedle patch for hair growth as well as a preparation method and application of the soluble microneedle patch. The patch comprises a flaky backing and soluble microneedles in array distribution, and needle bodies are formed by mixing cacumen biotae polysaccharide and oligomeric sodium hyaluronate and load homologous cacumen biotae exosome-like nano-vesicles. By means of an innovative synchronous extraction process, polysaccharide is directly extracted by means of sediment after exosome centrifugal extraction, waste is turned into wealth, the resource utilization rate is increased, and the production cost is reduced. The drug-containing needle body and the inactive backing are respectively prepared by adopting a double-step forming process, so that the drug loading efficiency and the mechanical strength are improved. According to the method, the same plant is fully utilized, and through the synergistic effect of the polysaccharide matrix and the exosome-like nano-vesicles, the regeneration of hair follicles and the growth of hair are remarkably promoted by combining micro-needle mechanical stimulation while local transdermal drug delivery is performed. The microneedle patch is good in biocompatibility, high in stability and convenient to use, and has the advantages of being high in transdermal efficiency, good in safety, high in compliance and the like.

Description

Technical Field

[0001] This invention belongs to the field of biomedical materials technology, specifically relating to a soluble microneedle patch for hair growth, its preparation method and application, especially its application in androgenetic alopecia. Background Technology

[0002] Androgenetic alopecia (AGA) is a degenerative hair follicle disease closely related to genetics and androgen levels, and it is prevalent in the global population. The main pathological features of AGA are progressive miniaturization of hair follicles, shortened hair growth cycles, and prolonged resting phases, ultimately leading to permanent hair loss. Current treatments include topical minoxidil, oral finasteride, hair transplantation, and low-energy laser therapy, but these all have drawbacks such as inconsistent efficacy, significant side effects, or high costs. There is an urgent clinical need for safe, effective, and well-adhered-to-patient new treatment options.

[0003] In recent years, plant exosome-like nanovesicles (PELNVs) have attracted attention due to their ability to carry a variety of active substances and cross the skin barrier. Meanwhile, plant polysaccharides, as natural biodegradable materials, possess excellent biocompatibility and film-forming properties, making them ideal matrices for soluble microneedles. However, current technologies mostly apply plant polysaccharides and exosomes separately to anti-inflammatory and moisturizing applications, lacking a systematic design specifically for hair follicle regeneration. Therefore, developing a soluble hair growth microneedle patch that simultaneously carries homologous plant PELNVs and plant polysaccharides for the efficient and safe treatment of AGA (acute hair follicle atrophy) has significant innovation and application prospects. Summary of the Invention

[0004] Therefore, the purpose of this invention is to provide a soluble microneedle patch for hair growth, its preparation method, and its application. This microneedle patch releases homologous plant polysaccharides and exosome-like nanovesicles in a synergistic manner. By embedding the drug into the matrix, the drug is uniformly dispersed throughout the needle. This provides a minimally invasive and painless soluble microneedle patch that is easy to prepare, has a large drug loading capacity, high nanovesicle delivery efficiency, long-term stability, and good mechanical properties. It promotes hair follicle regeneration and hair regeneration, overcoming the shortcomings of existing treatments for androgenetic alopecia, such as limited efficacy, significant side effects, and poor patient compliance.

[0005] Specifically, the present invention provides a soluble microneedle patch for hair growth, comprising a sheet-like backing and a plurality of soluble microneedles arranged thereon; The sheet-like backing material is selected from at least one of polyvinyl alcohol, amylopectin, polylactic acid, polyglycolic acid, polyethylene oxide, polyacrylic acid, polyacrylamide, a polymer of monobutyl maleate and methyl vinyl ether, polyvinylpyrrolidone, polyethylene glycol, polyvinyl alcohol, hydroxypropyl cellulose, hydroxyethyl cellulose, hydroxypropyl methyl cellulose, and sodium carboxymethyl cellulose. The microneedle body is formed by mixing Platycladus orientalis leaf polysaccharide with oligosodium hyaluronate, and is internally loaded with Platycladus orientalis leaf exosome-like nanovesicles.

[0006] In some specific embodiments of the present invention, the height of the microneedle body is 200-800 μm, the bottom diameter is 100-300 μm, the distance between adjacent needle tips is 200-500 μm, and the shape of the microneedle body is conical or pyramidal.

[0007] In some specific embodiments of the present invention, the particle size of the Platycladus orientalis leaf exosome-like nanovesicles is 20–500 nm.

[0008] In some specific embodiments of the present invention, the material of the sheet-like backing is polyvinyl alcohol.

[0009] In some specific embodiments of the present invention, the mass ratio of the Platycladus orientalis leaf exosome-like nanovesicles to Platycladus orientalis leaf polysaccharide and oligosodium hyaluronate is (2-4):(5-8):(2-4).

[0010] In some specific embodiments of the present invention, the Platycladus orientalis leaf exosome-like nanovesicles are extracted and purified from Platycladus orientalis leaves by differential centrifugation, ultrafiltration, density gradient centrifugation or tangential flow purification methods.

[0011] In some specific embodiments of the present invention, the Platycladus orientalis leaf polysaccharide is prepared by extraction using the precipitate generated during the extraction of Platycladus orientalis leaf exosome-like nanovesicles.

[0012] In some specific embodiments of the present invention, the preparation steps of the microneedle patch include: Step 1: Extract and purify arborvitae leaf exosome-like nanovesicles from arborvitae leaves by differential centrifugation, ultrafiltration, density gradient centrifugation or tangential flow purification method, and collect the precipitate generated during the extraction process; Step 2: The precipitate obtained in Step 1 is subjected to water extraction, protein removal and alcohol precipitation to extract Platycladus orientalis leaf polysaccharide; Step 3: Mix the arborvitae leaf polysaccharide obtained in Step 2 with oligosodium hyaluronate, and add the arborvitae leaf exosome-like nanovesicles obtained in S1 to obtain the needle mixture. Step 4: Prepare a backing solution, wherein the backing solution contains at least one water-soluble polymer material selected from at least one of polyvinyl alcohol, amylopectin, polylactic acid, polyglycolic acid, polyethylene oxide, polyacrylic acid, polyacrylamide, copolymer of 2-maleic monobutyl ester and methyl vinyl ether, polyvinylpyrrolidone, polyethylene glycol, hydroxypropyl cellulose, hydroxyethyl cellulose, hydroxypropyl methyl cellulose, and sodium carboxymethyl cellulose. Step 5: Inject the needle body mixture into the microneedle mold, fill the needle body part by centrifugation or vacuuming, and scrape off the excess solution; then inject the backing solution into the backing mold by centrifugation. Step 6: Dry and demold to obtain the soluble microneedle patch for hair growth.

[0013] In some specific embodiments of the present invention, the centrifugation speed in step 5 is 3000-5000 rpm, and the centrifugation time is 5-10 minutes; the vacuum degree of the vacuuming is ≤10 Pa.

[0014] In some specific embodiments of the present invention, the mass fraction of the backing solution in step 4 is 20% to 80%.

[0015] In some specific embodiments of the present invention, the drying and demolding conditions in step 6 are room temperature, humidity of 0% to 50%, and time of 24 to 72 hours.

[0016] This invention also provides a method for preparing a soluble microneedle patch for hair growth, characterized by comprising the following preparation steps: S1. Platycladus orientalis leaf exosome-like nanovesicles were extracted and purified from Platycladus orientalis leaves by differential centrifugation, ultrafiltration, density gradient centrifugation or tangential flow purification method, and the precipitate generated during the extraction process was collected. S2. The precipitate obtained in S1 was subjected to water extraction, protein removal and alcohol precipitation steps to extract Platycladus orientalis leaf polysaccharide; S3. Mix the arborvitae leaf polysaccharide obtained in S2 with oligosodium hyaluronate, and add the arborvitae leaf exosome-like nanovesicles obtained in S1 to obtain the needle-like mixture. S4. Prepare a backing solution, wherein the backing solution comprises at least one water-soluble polymer material selected from at least one of polyvinyl alcohol, amylopectin, polylactic acid, polyglycolic acid, polyethylene oxide, polyacrylic acid, polyacrylamide, copolymer of 2-maleic monobutyl ester and methyl vinyl ether, polyvinylpyrrolidone, polyethylene glycol, hydroxypropyl cellulose, hydroxyethyl cellulose, hydroxypropyl methyl cellulose, and sodium carboxymethyl cellulose; S5. Inject the needle body mixture into the microneedle mold, fill the needle body portion by centrifugation or vacuuming, and scrape off excess solution; then inject the backing solution into the backing mold by centrifugation. S6. Dry and demold to obtain the soluble microneedle patch for hair growth.

[0017] In some specific embodiments of the present invention, the centrifugation speed in S4 is 3000-5000 rpm, and the centrifugation time is 5-10 minutes; the vacuum degree of the vacuuming is ≤10 Pa.

[0018] In some specific embodiments of the present invention, the mass fraction of the backing solution in S5 is 20% to 80%.

[0019] In some specific embodiments of the present invention, the drying and demolding conditions in S6 are room temperature, humidity of 0% to 50%, and time of 24 to 72 hours.

[0020] In some specific embodiments of the present invention, the mass ratio of the Platycladus orientalis leaf exosome-like nanovesicles to Platycladus orientalis leaf polysaccharide and oligosodium hyaluronate is (2-4):(5-8):(2-4).

[0021] The present invention also provides the use of any of the soluble microneedle patches for hair growth described in any one of the claims, or the soluble microneedle patches for hair growth prepared by any one of the preparation methods described in any one of the claims, in the preparation of a medicament for treating androgenetic alopecia.

[0022] The present invention has the following significant advantages and effects compared with the prior art: (1) Homologous synergistic effect enhances hair growth efficacy and achieves multi-channel regulation of hair follicle cycle. Existing hair regrowth technologies often rely on single active ingredients, making it difficult to achieve synergistic effects. Furthermore, nanoscale active substances such as exosomes have low delivery efficiency and struggle to maintain their effects. In this invention, the arborvitae leaf polysaccharide and exosome-like nanovesicles loaded in the needle are both derived from arborvitae leaves. These two components exhibit significant synergistic effects in promoting hair follicle cell activation and improving the hair follicle microenvironment. Their combined release can precisely regulate the hair follicle cycle, enhancing hair growth. Simultaneously, by rationally setting the content of each component, sustained release of the nanovesicles is achieved, overcoming the shortcomings of traditional exosome liquid formulations such as "easy loss of biological activity, low delivery efficiency, and difficulty in achieving long-lasting effects." This significantly improves the transdermal delivery efficiency of macromolecular and nanoscale active substances and the stability of the hair regrowth therapeutic effect.

[0023] (2) Improved resource utilization efficiency and production benefits, breaking through the limitations of traditional extraction. Compared to the inefficient model of existing exosome extraction processes that involve "extracting a single component and discarding byproducts," this invention innovatively proposes a "simultaneous extraction scheme": during the centrifugation extraction of exosome-like nanovesicles from Platycladus orientalis leaves, plant polysaccharides are directly extracted from the precipitate generated during the extraction process, achieving "dual utilization of a single source" for waste resource utilization. This approach not only avoids raw material waste but also simplifies the production process, significantly improves the comprehensive utilization rate and overall production efficiency of Platycladus orientalis leaf raw materials, reduces raw material costs, and solves the technical pain points of "low resource utilization and redundant production processes" in traditional plant active ingredient extraction.

[0024] (3) The two-step molding process optimizes drug delivery performance, taking into account both mechanical strength and activity conservation. Existing microneedle patches often suffer from the contradiction of "uneven distribution of active ingredients leading to waste" and "insufficient mechanical strength hindering transdermal penetration." This invention employs a "two-step molding process": first, active needles containing Platycladus orientalis leaf polysaccharides and exosome-like nanovesicles are molded; then, a backing without active ingredients is molded. This design, on the one hand, ensures sufficient mechanical strength of the microneedle patch through the backing structure, and by precisely designing the microneedle structural parameters (needle height 200–800 μm, base diameter 100–300 μm, spacing 200–500 μm), ensures that the needles can effectively penetrate the stratum corneum of the skin, solving the problems of "insufficient transdermal depth and low drug delivery efficiency" of traditional soluble microneedles. On the other hand, the design of drug-loaded only on the needles avoids the waste of active ingredients in non-drug delivery areas, and the matrix is ​​completely soluble with no non-degradable residues, further reducing the loss of active substances and improving drug delivery accuracy.

[0025] (4) High safety and low side effects reduce the risk of clinical application. Existing hair regrowth products often suffer from poor biocompatibility, high risk of immune rejection, and significant side effects due to the complex origin of their ingredients (such as chemically synthesized drugs and heterologous biological components). The microneedle patch of this invention uses needle materials (polysaccharides and exosome-like nanovesicles) derived from natural arborvitae leaves, exhibiting excellent biocompatibility. This reduces immune rejection reactions caused by heterologous components from the source, resulting in higher safety and fewer side effects. Furthermore, the continuous release of medication reduces the frequency of administration, lowering the physical burden of long-term use and solving the problem of "frequent administration and low patient compliance" in traditional hair regrowth treatments, thus providing a safe guarantee for long-term clinical use.

[0026] (5) Improved storage and transportation convenience and bioactivity stability, accelerating clinical translation. Existing exosome-related products are mostly in liquid form, which has limitations such as demanding storage conditions, easy degradation of bioactivity during transportation, and short shelf life, making it difficult to meet the needs of clinical translation. This invention loads exosome-like nanovesicles from Platycladus orientalis leaves into soluble microneedle patches. The solid dosage form is not only easy to store and transport, but also more effectively maintains the bioactivity of exosomes, extending the product's shelf life. Simultaneously, the product has advantages such as low raw material cost, simple preparation process (two-step centrifugation), and removable backing that does not affect aesthetics (improving patient compliance). It perfectly meets the clinical translation requirements of "low cost, easy production, high stability, and high compliance," and has clear clinical application prospects. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 The provided images are scanning electron microscope (SEM) images of the "glucose bubble homology" hair growth microneedle patch and fluorescence distribution maps of the drug within the needle.

[0029] Figure 2 The provided data is a force-displacement curve of the "sugar bubble homology" hair growth microneedle patch.

[0030] Figure 3 The image provided shows the effect of treating AGA mice with "sugar bubble homology" hair growth microneedle patches.

[0031] Figure 4 This is a graph showing the hair coverage of AGA mice treated with "glucose bubble homology" hair growth microneedle patches.

[0032] Figure 5 This is a graph showing the change in transdermal water evaporation value of mouse skin treated with the "sugar bubble homology" hair growth microneedle patch prepared in this invention. Detailed Implementation

[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of the present invention and should not be used to limit the scope of protection of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Protection range.

[0034] Example 1: Preparation of soluble microneedle patches for hair growth The specific operating steps are as follows: S1. Fresh arborvitae leaves and PBS were mixed and homogenized in a mixer. The supernatant obtained after filtering the homogenate was extracted and purified by differential centrifugation combined with tangential flow technology to obtain arborvitae leaf exosome-like nanovesicles. At the same time, the precipitate was collected for the preparation of arborvitae leaf polysaccharides. S2. The precipitate obtained in S1 was extracted with hot water (95℃) for 2 hours, repeated once, centrifuged at 4000 r / min for 10 min, and the supernatant was collected and concentrated by rotary evaporation under reduced pressure at 60℃. The hot water extract was deproteinized using the Sevage method. Three volumes of anhydrous ethanol were added to the deproteinized crude polysaccharide solution, and the mixture was freeze-dried under vacuum at a pressure of -0.08 MPa to -0.098 MPa and a temperature of -50℃ to -40℃ to obtain Platycladus orientalis leaf polysaccharide. Compared with independent polysaccharide extraction, this method reduces raw material consumption and shortens the overall preparation cycle.

[0035] S3. Take 1.0 g of Platycladus orientalis leaf polysaccharide obtained in S2 and 0.6 g of oligomeric hyaluronic acid, dissolve and disperse them in 1.5 mL of Platycladus orientalis leaf exosome-like nanovesicle solution with a concentration of 25 mg / mL, and obtain a mixed solution. This mass ratio was obtained by screening different ratios of solutions through previous investigation of their mechanical properties.

[0036] S4. Dissolve and disperse 0.2 g of polyvinyl alcohol in 1.0 mL of ultrapure water to obtain a 20% polyvinyl alcohol aqueous solution.

[0037] S5. Inject the mixed solution prepared in S3 into a custom polydimethylsiloxane (PDMS, Sylgard 184) microneedle array mold. Centrifuge the PDMS microneedle array mold at 3500 rpm for 5 minutes to completely fill it. Remove the mold, scrape off the excess premixed solution, and immediately inject the polyvinyl alcohol aqueous solution prepared in S4. Then, centrifuge the PDMS microneedle array mold at 3500 rpm for 5 minutes to form a backing before removing it.

[0038] S6. Place the PDMS microneedle array mold in a silica gel desiccator and dry it at room temperature for 24 h to obtain a soluble microneedle patch for hair growth loaded with Platycladus orientalis leaf exosome-like nanovesicles POELNVs and Platycladus orientalis leaf polysaccharide POP.

[0039] In this embodiment, a solid soluble microneedle patch was obtained by mixing a solution of Platycladus orientalis leaf exosome-like nanovesicles with polysaccharides and polymers. The preparation process of this solid soluble microneedle patch is mild, without extreme conditions, simple, and can be stored at room temperature in a dry environment, effectively achieving transdermal delivery of Platycladus orientalis leaf exosome-like nanovesicles. Furthermore, the Platycladus orientalis leaf polysaccharide, serving as the microneedle matrix, also possesses hair-growth properties, compensating for the low drug loading capacity of the needles, making this soluble microneedle a "functional carrier" with both delivery and therapeutic effects.

[0040] In this embodiment, the soluble microneedle patch is prepared by a two-step centrifugation method. The needle body contains Platycladus orientalis leaf exosome-like nanovesicles and Platycladus orientalis leaf polysaccharide, while the patch backing does not contain these two substances, thus avoiding waste of active ingredients. During use, the microneedle body absorbs tissue fluid and dissolves rapidly. The Platycladus orientalis leaf exosome-like nanovesicles, which play the main therapeutic role, are completely released into the skin along with the dissolution of the Platycladus orientalis leaf polysaccharide matrix. The patch backing can be removed, resulting in a short drug delivery process, no impact on aesthetics, and high patient compliance.

[0041] Example 2: Physicochemical characterization of soluble microneedle patches for hair growth 1. Morphological Characterization: The surface morphology and size of the soluble microneedles prepared in Example 1 were examined using scanning electron microscopy. Under vacuum conditions, gold heavy metal atoms were sputtered onto the surface of the soluble microneedles prepared in Example 1, and then the three-dimensional morphology of the microneedles was observed using scanning electron microscopy. Simultaneously, to clarify the distribution of the drug within the microneedles, soluble microneedles loaded with dual fluorescence were prepared by loading cell membrane red fluorescent probes (DiL) onto exosome-like nanovesicles from Platycladus orientalis leaves and loading fluorescein isothiocyanate (FITC) onto Platycladus orientalis polysaccharides, following the method described in Example 1. The microneedles were then imaged using laser scanning confocal microscopy (CLSM).

[0042] Microneedle morphology diagram as follows Figure 1 As shown, the left image is a morphological image under a scanning electron microscope, and the right image is a fluorescence microscopy image showing the distribution of Platycladus orientalis leaf exosome-like nanovesicles and Platycladus orientalis leaf polysaccharides in microneedles. From Figure 1 As can be seen from the present invention, the microneedles prepared by this invention have a height of approximately 500 μm, a base width of 200 μm, and a spacing of 500 μm between each microneedle. Exosome-like nanovesicles and polysaccharides from Platycladus orientalis leaves are uniformly distributed within the needles.

[0043] 2. Mechanical Performance Testing: The mechanical properties of the soluble microneedles prepared in Example 1 were characterized using a universal testing machine. A microneedle patch containing a 15×15 array was fixed in the center of the stage of the universal testing machine with double-sided tape, tip facing upwards. The distance between the microneedle tip and the sensor was set to 0.5 cm. Subsequently, the sensor parameters were adjusted, and after zeroing, vertical pressure was applied, causing the sensor to move vertically towards the stainless steel plate at a constant speed of 1.0 mm / min. The sensor displacement after contact with the microneedle tip and the corresponding resistance to the microneedle were recorded. A curve was plotted with resistance as the abscissa and deformation as the ordinate.

[0044] The mechanical properties of microneedles are shown in the figure. Figure 2 As shown, by Figure 2 As can be seen, no inflection point was observed in the force-displacement curve, and the compressive force of the microneedle increased with increasing displacement. When the displacement increased to 0.6 mm, the compressive force of a single needle was greater than 0.2 N. This shows that the soluble microneedles of the present invention have sufficient mechanical properties to pierce the skin and deliver drugs to the hair follicle.

[0045] Example 3: Efficacy test of soluble microneedle patches for hair growth Soluble microneedle patches prepared in Example 1 and simple Platycladus orientalis leaf polysaccharide microneedle patches were selected. The preparation of the simple Platycladus orientalis leaf polysaccharide microneedles was basically the same as that of the "sugar vesicle homology" microneedles, except that the solvent in the needle body solution was replaced with the same volume of distilled water instead of Platycladus orientalis leaf exosome solution. One microneedle patch was applied to AGA model mice by pressing with the fingertip, and the medication was administered simultaneously with modeling. The administration was carried out 4 times, on days 1, 3, 6, and 10. After the 28-day hair cycle, the hair regrowth of the mice was recorded. A control group was set up, and the AGA model mice in the control group did not receive any treatment. like Figure 3 , 4 As shown, AGA mice treated with soluble microneedle patches containing "glycovesicle homology" of Platycladus orientalis leaf exosome-like nanovesicles and Platycladus orientalis leaf polysaccharides exhibited significant hair regeneration, while AGA model mice that did not receive any treatment did not show hair regeneration. Moreover, compared with Platycladus orientalis leaf polysaccharide microneedles alone, the "glycovesicle homology" microneedles showed faster hair growth and higher hair quality, demonstrating excellent therapeutic effects.

[0046] Example 4: Safety test of soluble microneedle patches for hair growth in vivo for topical use The soluble microneedle patch prepared in Example 1 was used for safety testing, and the administration procedure was consistent with that for AGA treatment. Transepidermal water loss (TEWL) was recorded daily, and after there was no difference in TEWL between the treatment group and the control group, TEWL was recorded weekly.

[0047] like Figure 5 As shown, TEWL significantly increased after 5 microneedle patch administrations, then returned to a level not significantly different from the normal group, indicating that microneedle administration penetrates the skin and temporarily forms micropores, allowing the skin barrier to recover quickly. This demonstrates good safety for local use in vivo.

[0048] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to the technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, the above-described features have similar functions to (but are not limited to) those disclosed in this application.

Claims

1. A dissolvable microneedle patch for hair growth, characterized by: The patch comprises a sheet-shaped backing and a plurality of soluble microneedle bodies arranged thereon. The material of the sheet-shaped backing is selected from at least one of polyvinyl alcohol, amylopectin, polylactic acid, polyglycolic acid, polyethylene oxide, polyacrylic acid, polyacrylamide, a polymer of 2-maleic acid monobutyl ester and methyl vinyl ether, polyvinylpyrrolidone, polyethylene glycol, polyvinyl alcohol, hydroxypropyl cellulose, hydroxyethyl cellulose, hydroxypropyl methyl cellulose, and sodium carboxymethyl cellulose. The microneedle bodies are formed by mixing Platycladus orientalis polysaccharide and sodium hyaluronate and internally loaded with Platycladus orientalis exosome-like nanovesicles.

2. The dissolvable microneedle patch for hair growth according to claim 1, wherein, The microneedle bodies have a height of 200-800 μm, a bottom diameter of 100-300 μm, a distance between adjacent needle tips of 200-500 μm, and a conical or pyramidal shape.

3. The dissolvable microneedle patch for hair growth according to claim 1, wherein The Platycladus orientalis exosome-like nanovesicles have a particle size of 20-500 nm.

4. The dissolvable microneedle patch for hair growth according to any one of claims 1-3, wherein, The mass ratio of the Platycladus orientalis exosome-like nanovesicles, Platycladus orientalis polysaccharide, and sodium hyaluronate is (2-4):(5-8):(2-4).

5. A method for preparing a dissolvable microneedle patch for hair growth, characterized by, The preparation steps include: S1. Extracting and purifying Platycladus orientalis exosome-like nanovesicles from Platycladus orientalis by differential centrifugation, ultrafiltration, density gradient centrifugation, or tangential flow purification, and collecting the precipitate produced during the extraction process; S2. Extracting Platycladus orientalis polysaccharide from the precipitate obtained in S1 by water extraction, deproteinization, and alcohol precipitation; S3. Mixing the Platycladus orientalis polysaccharide obtained in S2 with sodium hyaluronate and adding the Platycladus orientalis exosome-like nanovesicles obtained in S1 to obtain a needle body mixture; S4. Preparing a backing solution, wherein the backing solution comprises at least one water-soluble polymer material selected from at least one of polyvinyl alcohol, amylopectin, polylactic acid, polyglycolic acid, polyethylene oxide, polyacrylic acid, polyacrylamide, a copolymer of 2-maleic acid monobutyl ester and methyl vinyl ether, polyvinylpyrrolidone, polyethylene glycol, hydroxypropyl cellulose, hydroxyethyl cellulose, hydroxypropyl methyl cellulose, and sodium carboxymethyl cellulose; S5. Injecting the needle body mixture into a microneedle mold, filling the needle body part by centrifugation or vacuum extraction, and scraping off the excess solution; Subsequently, the backing solution is injected into the backing mold by centrifugation; S6. Drying and demolding to obtain the soluble microneedle patch for hair growth.

6. The method for preparing the soluble microneedle patch for hair growth as described in claim 5, characterized in that, The centrifugation in S5 has a speed of 3000-5000 rpm and a centrifugation time of 5-10 minutes; the vacuum extraction has a vacuum degree of ≤10 Pa.

7. The method of claim 5, wherein the soluble microneedle patch is prepared by the steps of: a) dissolving the microneedle patch in a solvent; b) mixing the microneedle patch with a pharmaceutically acceptable carrier; and c) drying the mixture. The mass fraction of the backing solution in S4 is 20%-80%.

8. The method for preparing the soluble microneedle patch for hair growth as described in claim 5, characterized in that, The drying and demolding in S6 is performed at room temperature, a humidity of 0%-50%, and for a time of 24-72 hours.

9. The method of making a dissolvable microneedle patch for hair growth according to any one of claims 5-8, wherein, The mass ratio of the Platycladus orientalis exosome-like nanovesicles, Platycladus orientalis polysaccharide, and sodium hyaluronate is 0.5:0.5:0.1-3:3:

2.

10. Use of the soluble microneedle patch for hair growth according to any one of claims 1-4 or prepared by the preparation method according to any one of claims 5-9 in the preparation of a medicament for treating androgenetic alopecia.

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