A tofacitinib nano-microneedle preparation and its preparation method and application

Abstract

The present invention provides a tofacitinib nano-microneedle preparation and its preparation method and application, which belong to the field of medical technology. The tofacitinib nano-microneedle preparation prepared by the present invention is a soluble microneedle, which can enable the drug to penetrate the stratum corneum of the skin, deliver the drug into the dermis, directly act on the hair follicle cells, and exert the therapeutic effect as soon as possible. Compared with traditional transdermal drug delivery techniques and injections such as ointments and skin patches, soluble microneedle drug delivery technology is more efficient, the variety of drugs is richer, and the length of the microneedle under the skin does not touch the skin pain nerve endings, does not cause pain, and the penetration depth of the soluble microneedle does not damage the capillary network, and the probability of bacterial infection is greatly reduced. After microneedle administration, the skin epidermis has only micron-level wounds, which can be healed within 24 to 48 hours. In actual use, the soluble microneedle does not require special operation, and the storage conditions are relatively mild.

Description

Technical Field

[0001] The present invention relates to the field of medical technology, and in particular to a tofacitinib nano-microneedle preparation and a preparation method and application thereof. Background Art

[0002] Alopecia areata (AA) is a common, relapsing and remitting autoimmune hair loss condition, which is generally believed to be related to autoimmune, genetic, emotional stress and endocrine factors. From single patches to multiple patches, to the loss of hair on the entire scalp (known as alopecia totalis [AT]), and complete loss of scalp and body hair (known as alopecia universalis [AU]). The incidence of alopecia areata in the population is about 0.1% to 0.2%, and 1.7% to 2.0% of the population will experience alopecia areata in their lifetime. Both children and adults can be affected. Although it is uncommon in children under 3 years old, most patients are younger. 30% to 50% of alopecia areata patients can recover on their own within 1 year, but 14% to 25% of patients will continue to worsen and even develop into alopecia totalis or alopecia universalis. At present, the main treatments for alopecia areata are topical or intralesional injection of glucocorticoids and local stimulation therapy. Systemic treatments can also include oral glucocorticoids or high-dose immunosuppressants such as methotrexate, cyclosporine A, mycophenolate mofetil, or azathioprine. Many of the inflammatory responses involved in the pathogenesis of alopecia areata co-signal through the Janus kinase-signal transducer and activator of transcription (JAK-stat) pathway, in which proinflammatory cytokines such as interferon-c (IFN-c) and interleukin-15 (IL-15) activate JAK. Blocking this pathway with JAK inhibitors is a new therapeutic target.

[0003] Tofacitinib is an oral Janus kinase inhibitor (JAK) with immunomodulatory and anti-inflammatory activity. After administration, tofacitinib binds to JAK and prevents activation of the JAK signal transducer and activator of transcription (STAT) signaling pathway. This may reduce the production of proinflammatory cytokines, such as interleukin (IL)-6, -7, -15, -21, interferon-α and -β, and may prevent inflammatory responses and damage caused by inflammation caused by certain immune diseases. Tofacitinib mainly inhibits JAK1 and JAK3, and slightly inhibits JAK2, thereby inhibiting related factors that depend on the JAK / STAT pathway, such as IFN-γ, IL-6 and IL-15 signal transduction, blocking intracellular signal transduction, and inhibiting immune cell activation and T cell-mediated inflammatory diseases. It has been approved by the FDA for the treatment of adult patients with moderate to severe active rheumatoid arthritis who have insufficient efficacy or intolerance to methotrexate. In recent years, some studies have shown that it can induce or promote human hair growth, while improving the blood circulation and nutrient supply of the scalp, so that hair follicles can grow again. It is suitable for baldness and hair loss caused by various reasons, and is a safe and effective method for treating baldness and hair loss. Traditional treatment methods for tofacitinib mainly include oral administration and topical application. However, after oral administration, tofacitinib will reach the peak plasma drug concentration within 0.5 to 1 hour, and the elimination half-life is only 3 hours, and it is prone to nasopharyngitis, respiratory tract infection, urinary tract infection, gastrointestinal reaction, nausea and other adverse reactions. Topical administration requires daily application and massage to promote absorption. Patients with long-term use have poor compliance and the dosage is uncertain. Therefore, tofacitinib is made into nanoparticles using electrostatic spray technology and encapsulated in soluble microneedles. Nanoparticles can solve the problems of low bioavailability and short half-life of tofacitinib, and microneedles solve the problems of low compliance of patients and oral side effects. Summary of the invention

[0004] In view of this, the purpose of the present invention is to provide a tofacitinib nano-microneedle preparation and its preparation method and application. The tofacitinib nano-microneedle preparation prepared by the present invention delivers drugs by microneedle route, can directly pass through the stratum corneum, reach the dermis, directly act on the hair follicle cells, and exert the therapeutic effect as soon as possible.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] The present invention provides a method for preparing a tofacitinib nano-microneedle preparation, comprising the following steps:

[0007] The tofacitinib, poly(lactic-co-glycolic acid) and solvent are mixed and then electrosprayed to obtain electrosprayed nanoparticles;

[0008] Mixing hyaluronic acid, bletilla striata polysaccharide and water to obtain a needle solution;

[0009] Mixing the needle solution and the electrosprayed nanoparticles to obtain a matrix solution;

[0010] The matrix solution is molded using a microneedle mold, and then coated with a polyvinyl alcohol solution, followed by drying to obtain the tofacitinib nano-microneedle preparation.

[0011] Preferably, the mass ratio of tofacitinib to the polylactic acid-glycolic acid copolymer is 1:3 to 1:7.

[0012] Preferably, the number average molecular weight of the polylactic acid-glycolic acid copolymer is 50,000.

[0013] Preferably, the injection speed of the electrospray is 0.1-1 mm / min, the voltage is 15-25 V, and the receiving distance is 7-8 cm.

[0014] Preferably, the mass fraction of bletilla striata polysaccharide in the needle solution is 15-20%, and the mass fraction of hyaluronic acid is 10-15%.

[0015] Preferably, the mass fraction of the polyvinyl alcohol solution is 20-25%.

[0016] Preferably, the coating has a thickness of 0.30 to 0.50 mm.

[0017] The present invention also provides a tofacitinib nano-microneedle preparation prepared by the preparation method described in the above technical scheme.

[0018] The present invention also provides the use of the tofacitinib nano-microneedle preparation described in the above technical solution in the preparation of an anti-hair loss agent.

[0019] The invention provides a method for preparing a tofacitinib nano-microneedle preparation, comprising the following steps: mixing tofacitinib, a polylactic acid-glycolic acid copolymer and a solvent, and then electrospraying the mixture to obtain electrosprayed nanoparticles; mixing hyaluronic acid, bletilla striata polysaccharide and water to obtain a needle body solution; mixing the needle body solution and the electrosprayed nanoparticles to obtain a matrix solution; and using a microneedle mold to mold the matrix solution, coating it with a polyvinyl alcohol solution, and drying the mixture to obtain the tofacitinib nano-microneedle preparation.

[0020] The tofacitinib nano-microneedle preparation prepared by the present invention is a soluble microneedle that enables drugs to penetrate the stratum corneum of the skin, deliver drugs into the dermis, directly act on hair follicle cells, and exert curative effect as soon as possible. Compared with traditional transdermal drug delivery techniques and injections such as ointments and skin patches, soluble microneedle drug delivery techniques are more efficient, the types of drugs are richer, and the length of the microneedle under the skin does not touch the skin pain nerve endings, does not cause pain, and the penetration depth of the soluble microneedle does not damage the capillary network, and the probability of bacterial infection is greatly reduced. After microneedle administration, the skin epidermis has only micron-level wounds, which can be healed within 24 to 48 hours. In actual use, soluble microneedles do not need to be operated by a special person, and the storage conditions are relatively mild. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 TEM image of the nanoparticles of the comparative example;

[0022] Figure 2 is a transmission electron microscope image of the nanoparticles of Example 3;

[0023] Figure 3 The in vitro release curves of the nanoparticles prepared in Example 3 under different pH conditions (Mean±SD, n=3);

[0024] Figure 4 This is a bright field image of the nano-microneedle preparation prepared in Example 3 under an inverted fluorescence microscope;

[0025] Figure 5 This is a scanning electron microscope image of the nano-microneedle preparation prepared in Example 3. DETAILED DESCRIPTION

[0026] The present invention provides a method for preparing a tofacitinib nano-microneedle preparation, comprising the following steps:

[0027] The tofacitinib, poly(lactic-co-glycolic acid) and solvent are mixed and then electrosprayed to obtain electrosprayed nanoparticles;

[0028] Mixing hyaluronic acid, bletilla striata polysaccharide and water to obtain a needle solution;

[0029] Mixing the needle solution and the electrosprayed nanoparticles to obtain a matrix solution;

[0030] The matrix solution is molded using a microneedle mold, and then coated with a polyvinyl alcohol solution, followed by drying to obtain the tofacitinib nano-microneedle preparation.

[0031] In the present invention, unless otherwise specified, the raw materials used are all commercially available products in the art.

[0032] The invention mixes tofacitinib, a polylactic acid-glycolic acid copolymer and a solvent and then performs electrospraying to obtain electrosprayed nanoparticles.

[0033] In the present invention, the mass ratio of tofacitinib to the polylactic acid-glycolic acid copolymer is preferably 1:3 to 1:7.

[0034] In the present invention, the solvent is preferably acetone. The present invention has no particular limitation on the amount of the solvent, as long as the tofacitinib and the polylactic acid-glycolic acid copolymer are uniformly mixed.

[0035] In the present invention, the number average molecular weight of the polylactic acid-glycolic acid copolymer is preferably 50,000.

[0036] In the present invention, the injection speed of the electrospray is preferably 0.1-1 mm / min, more preferably 0.5 mm / min, the voltage is preferably 15-25 V, and the receiving distance is preferably 7-8 cm.

[0037] In the present invention, the electrospraying is preferably performed in an electrospinning apparatus.

[0038] In the present invention, the mixed solution is preferably sucked up with a 5 mL syringe and placed in the push injection part of the electrospinning instrument to perform the electrospraying.

[0039] In the present invention, the receiving liquid of the electrospray is preferably distilled water.

[0040] In the present invention, the electrosprayed nanoparticle solution obtained by electrospraying is preferably freeze-dried to obtain the electrosprayed nanoparticles. The present invention has no particular limitation on the specific freeze-drying method, and any method well known to those skilled in the art can be used.

[0041] In the present invention, the particle size of the electrosprayed nanoparticles is preferably 170.3 to 217.2 nm.

[0042] The invention mixes hyaluronic acid, bletilla striata polysaccharide and water to obtain a needle solution.

[0043] In the present invention, the mass fraction of Bletilla striata polysaccharide in the needle solution is preferably 15-20%, and the mass fraction of hyaluronic acid is preferably 10-15%.

[0044] The present invention has no particular limitation on the amount of water used, as long as it can ensure uniform mixing.

[0045] The present invention preferably performs the mixing on a magnetic stirrer. The present invention has no particular limitation on the parameters of the magnetic stirrer.

[0046] After obtaining the needle body solution and the electrosprayed nanoparticles, the present invention mixes the needle body solution and the electrosprayed nanoparticles to obtain a matrix solution.

[0047] In the present invention, the solvent of the polyvinyl alcohol solution is preferably water.

[0048] After obtaining the matrix solution, the present invention uses a microneedle mold to shape the matrix solution, then coats it with a polyvinyl alcohol solution, and dries it to obtain the tofacitinib nano-microneedle preparation.

[0049] The present invention has no special limitation on the material and size parameters of the microneedle mold, and any microneedle mold well known to those skilled in the art can be used.

[0050] In the present invention, the microneedle mold is preferably pre-cleaned and dried in sequence before use. The present invention has no particular limitation on the specific methods of pre-cleaning and drying, and methods familiar to those skilled in the art may be used.

[0051] The present invention preferably uses a pipette to absorb 150 μL of the nanomatrix solution onto the surface of the microneedle pinholes of the mold, vacuum suction is performed, and after the suction is completed, the microneedle mold is taken out, the residual solution on the surface is wiped off, and then the polyvinyl alcohol solution (backing layer solution) is coated.

[0052] In the present invention, the mass fraction of the polyvinyl alcohol solution is preferably 20-25%.

[0053] In the present invention, the coating thickness is preferably 0.30 to 0.50 mm.

[0054] In the present invention, the drying is preferably room temperature drying, the drying is carried out under room temperature conditions, and the drying time is preferably 24 to 48 hours.

[0055] The present invention also provides a tofacitinib nano-microneedle preparation prepared by the preparation method described in the above technical scheme.

[0056] The present invention also provides the use of the tofacitinib nano-microneedle preparation described in the above technical solution in the preparation of an anti-hair loss agent.

[0057] The present invention has no particular limitation on the specific manner of the application, and any manner familiar to those skilled in the art may be used.

[0058] In order to further illustrate the present invention, the tofacitinib nano-microneedle preparation provided by the present invention and its preparation method and application are described in detail below in combination with examples, but they should not be construed as limiting the scope of protection of the present invention.

[0059] raw material:

[0060] Tofacitinib (TFB), also known as tofacitinib, has a molecular formula of C 16 H 20 N 6O, whose chemical name is 3-((3R, 4R)-4-methyl-3-(methyl(7H-pyrrolo[2,3-D]pyrimidin-4-yl)amino)piperidin-1-yl)-3-oxopropionitrile, was purchased from Wengjiang Reagent and is a drug that exerts a therapeutic effect.

[0061] Poly(lactic-co-glycolic acid) (PLGA), molecular weight 50,000, 50 / 50, purchased from Maya Reagent, was used as the carrier part of the nanoparticles.

[0062] Polyvinyl alcohol (PVP), Mw 27000, was purchased from MacLean's reagent and used to prepare the microneedle backing layer solution.

[0063] Hyaluronic acid (HA) was purchased from Huaxi Freda and used for the preparation of microneedle solution.

[0064] Bletilla striata polysaccharide (BSP) was purchased from Shanghai Ronghe Pharmaceutical Technology Development Co., Ltd. and used for the preparation of microneedle solution.

[0065] Example 1

[0066] (1) Weigh 11.43 mg of tofacitinib and 80 mg of PLGA and dissolve them in 4 mL of acetone.

[0067] (2) The solution obtained in step (1) was drawn into a 5 mL syringe and placed in the push injection part of the electrospinning instrument. The push injection speed was set to 0.5 mm / min and the voltage of the syringe was set to 20 V. The environmental parameters were kept stable. 30 mL of distilled water was used as the receiving liquid and the receiving distance was 7 cm. The electrosprayed nanoparticle solution was prepared and freeze-dried in a vacuum freeze dryer to obtain freeze-dried nanoparticle powder.

[0068] (3) Preparation of backing layer: Accurately weigh 4.0 g of PVA, prepare a 20% PVA solution with distilled water, and melt it in a magnetic stirrer until it becomes transparent.

[0069] (4) Preparation of needle solution: Accurately weigh 1.0 g BSP and 0.5 g HA, dissolve them together in 5 mL distilled water, and place on a magnetic stirrer until completely dissolved.

[0070] (5) Preparation of matrix solution: Accurately weigh 10 mg of freeze-dried nanoparticle powder, dissolve it in 2 mL of needle solution, and disperse it evenly by ultrasonication.

[0071] (6) Preparation of microneedles: Take out the pre-cleaned and dried microneedle mold, use a pipette to draw 150 μL of matrix solution on the surface of the mold pinhole, and evacuate for 30 minutes. After completion, take out the microneedle mold, wipe off the residual liquid on the surface, and continue to evacuate for 15 minutes. Apply the backing layer solution prepared in advance to the mold surface until it is evenly covered, and dry at room temperature for 24 hours.

[0072] Example 2

[0073] (1) Weigh 16 mg of tofacitinib and 80 mg of PLGA and dissolve them in 4 mL of acetone.

[0074] (2) The solution obtained in step (1) was drawn into a 5 mL syringe and placed in the push injection part of the electrospinning instrument. The push injection speed was set to 0.5 mm / min and the voltage of the syringe was set to 20 V. The environmental parameters were kept stable. 30 mL of distilled water was used as the receiving liquid and the receiving distance was 7 cm. The electrosprayed nanoparticle solution was prepared and freeze-dried in a vacuum freeze dryer to obtain freeze-dried nanoparticle powder.

[0075] (3) Preparation of backing layer: Accurately weigh 4.0 g of PVA, prepare a 20% PVA solution with distilled water, and melt it in a magnetic stirrer until it becomes transparent.

[0076] (4) Preparation of needle solution: Accurately weigh 1.0 g BSP and 0.5 g HA, dissolve them together in 5 mL distilled water, and place on a magnetic stirrer until completely dissolved.

[0077] (5) Preparation of matrix solution: Accurately weigh 10 mg of freeze-dried nanoparticle powder, dissolve it in 2 mL of needle solution, and disperse it evenly by ultrasonication.

[0078] (6) Preparation of microneedles: Take out the pre-cleaned and dried microneedle mold, use a pipette to draw 150 μL of matrix solution on the surface of the mold pinhole, and evacuate for 30 minutes. After completion, take out the microneedle mold, wipe off the residual liquid on the surface, and continue to evacuate for 15 minutes. Apply the backing layer solution prepared in advance to the mold surface until it is evenly covered, and dry at room temperature for 24 hours.

[0079] Example 3

[0080] (1) Weigh 26.67 mg of tofacitinib and 80 mg of PLGA and dissolve them in 4 mL of acetone.

[0081] (2) The solution obtained in step (1) was drawn into a 5 mL syringe and placed in the push injection part of the electrospinning instrument. The push injection speed was set to 0.5 mm / min and the voltage of the syringe was set to 20 V. The environmental parameters were kept stable. 30 mL of distilled water was used as the receiving liquid and the receiving distance was 8 cm. The electrosprayed nanoparticle solution was prepared and freeze-dried in a vacuum freeze dryer to obtain freeze-dried nanoparticle powder.

[0082] (3) Preparation of backing layer: Accurately weigh 4.0 g of PVA, prepare a 20% PVA solution with distilled water, and melt it in a magnetic stirrer until it becomes transparent.

[0083] (4) Preparation of needle solution: Accurately weigh 1.0 g BSP and 0.5 g HA, dissolve them together in 5 mL distilled water, and place on a magnetic stirrer until completely dissolved.

[0084] (5) Preparation of matrix solution: Accurately weigh 10 mg of freeze-dried nanoparticle powder, dissolve it in an appropriate amount of needle solution, and disperse it evenly by ultrasound.

[0085] (6) Preparation of microneedles: Take out the pre-cleaned and dried microneedle mold, use a pipette to draw 150 μL of matrix solution on the pinhole surface of the mold, and evacuate for 30 minutes. After completion, take out the microneedle mold, remove the residual liquid on the surface, and continue to evacuate for 15 minutes. Apply the backing layer solution prepared in advance to the mold surface until it is evenly covered, and dry at room temperature for 24 hours.

[0086] Comparative Example

[0087] (1) Weigh 80 mg of PLGA and dissolve it in 4 mL of acetone.

[0088] (2) The solution obtained in step (1) was drawn into a 5 mL syringe and placed in the push injection part of the electrospinning instrument. The push injection speed was set to 0.5 mm / min and the voltage of the syringe was set to 20 V. The environmental parameters were kept stable. 30 mL of distilled water was used as the receiving liquid, and the receiving distance was 7 cm. The electrosprayed nanoparticle solution was prepared and frozen in a vacuum freeze dryer to obtain freeze-dried nanoparticle powder.

[0089] (3) Preparation of backing layer: Accurately weigh 4.0 g of PVA, prepare a 20% PVA solution with distilled water, and melt it in a magnetic stirrer until it becomes transparent.

[0090] (4) Preparation of needle solution: Accurately weigh 1.0 g BSP and 0.5 g HA, dissolve them together in 5 mL distilled water, and place on a magnetic stirrer until completely dissolved.

[0091] (5) Preparation of matrix solution: Accurately weigh 10 mg of freeze-dried nanoparticle powder, dissolve it in an appropriate amount of needle solution, and disperse it evenly by ultrasound.

[0092] (6) Preparation of microneedles: Take out the pre-cleaned and dried microneedle mold, use a pipette to draw 150 μL of matrix solution on the surface of the mold pinhole, and evacuate for 30 minutes. After completion, take out the microneedle mold, wipe off the residual liquid on the surface, and continue to evacuate for 15 minutes. Apply the backing layer solution prepared in advance to the mold surface until it is evenly covered, and dry at room temperature for 24 hours.

[0093] Morphology and structure characterization of freeze-dried nanoparticle powder: Use a copper mesh to dip an appropriate amount of the electrosprayed nanoparticle solution prepared in the comparative example and Example 3, and after natural air drying, use a transmission electron microscope to observe the morphology and particle size of the nanoparticles on the copper mesh and take photos to record. The operating voltage of the transmission electron microscope is 100kV. Take a small amount of freeze-dried powder of electrosprayed nanoparticles and sprinkle it on the sample cover, spray gold, and then perform imaging observation under high pressure conditions. Figure 1 and 2 , Figure 1 The transmission electron microscope image of the nanoparticles in the comparative example is shown in FIG. Figure 2 is a transmission electron microscope image of the nanoparticles of Example 3, Figures 1-2 It can be seen that the particle sizes of the electrosprayed nanoparticles prepared in the comparative example and example 3 are about 170.3 nm and 217.2 nm, respectively.

[0094] In vitro drug release experiment of nanoparticles: The in vitro drug release characteristics of the prepared tofacitinib nanoparticles were determined by the dialysis bag method. Accurately pipette 2 mL of the electrosprayed nanoparticle solution after dialyzation in Example 3 and place it in a pretreated dialysis bag (molecular weight cutoff is 3500). The above dialysis bags were placed in conical flasks containing 50 mL of release medium (PBS, pH 5.5, 7.4, containing 0.5% Tween 80), and placed in a constant temperature water bath oscillator at (37±0.5)°C, 100r / min. Take 2 mL of the dialysate in the conical flask at 0, 0.5, 1, 2, 4, 6, 8, 10, 12, 24, and 48h, and supplement with an equal amount of fresh release medium. Repeat 3 times in parallel, measure the absorbance, calculate the cumulative release rate, and examine its release behavior. The results are as follows Figure 3 As shown, it can be seen that compared with the original drug, the prepared electrosprayed nanoparticles have a sustained release effect.

[0095] Characterization of microneedle morphology: The microneedles prepared in Example 3 were fixed flat on a glass slide, and the morphology of the microneedles was observed using an inverted fluorescence microscope. Figure 4 , Figure 4 The image of the microneedle preparation prepared in Example 3 under an inverted fluorescence microscope is shown in the bright field. The microneedles prepared in Example 3 were placed flat on a table, and the surface of the microneedles was subjected to gold spraying. The morphology of the microneedles was observed using a scanning electron microscope. Figure 5 As shown, Figure 5 This is a scanning electron microscope image of the microneedles prepared in Example 3. It can be seen that the prepared microneedles have a smooth surface, a neat array, and a good needle shape.

[0096] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A method for preparing a tofacitinib nano-microneedle preparation, characterized in that: The steps are: (1) Weigh 26.67 mg of tofacitinib and 80 mg of PLGA and dissolve them in 4 mL of acetone; (2) The solution obtained in step (1) was drawn into a 5 mL syringe and placed in the push injection part of the electrospinning instrument. The push injection speed was set to 0.5 mm / min and the voltage of the syringe was set to 20 V. The environmental parameters were kept stable. 30 mL of distilled water was used as the receiving liquid and the receiving distance was 8 cm to prepare the electrosprayed nanoparticle solution. The solution was freeze-dried in a vacuum freeze dryer to obtain freeze-dried nanoparticle powder. (3) Preparation of backing layer: Accurately weigh 4.0 g of PVA, prepare a 20% PVA solution with distilled water, and melt it in a magnetic stirrer until it becomes transparent; (4) Preparation of needle solution: accurately weigh 1.0 g BSP and 0.5 g HA, dissolve them together in 5 mL distilled water, and place on a magnetic stirrer until completely dissolved; (5) Preparation of matrix solution: Accurately weigh 10 mg of freeze-dried nanoparticle powder, dissolve it in an appropriate amount of needle solution, and disperse it evenly by ultrasonication; (6) Preparation of microneedles: Take out the pre-cleaned and dried microneedle mold, and use a pipette to draw 150 μL of the matrix solution on the pinhole surface of the mold. Vacuum for 30 min. After the end, take out the microneedle mold, remove the residual liquid on the surface, continue to vacuum for 15 min, and apply the pre-prepared backing layer solution to the mold surface until it is evenly covered. Dry at room temperature for 24 h.

2. The tofacitinib nano-microneedle preparation prepared by the preparation method according to claim 1.

3. Use of the tofacitinib nano-microneedle preparation according to claim 2 in the preparation of an anti-hair loss agent.

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