Composite microneedle material as well as preparation method and application thereof

Abstract

The invention discloses a composite microneedle material. The composite material comprises a needle tip and a substrate, wherein the needle tip is made of composite hydrogel loaded with nano particles; the nano particles are photo-thermal conjugated polymer nano particles with pH response; and the substrate is hyaluronic acid. According to the application, the advantages that the microneedle remotely regulates and controls the ion channel, the ROS responds to release the nano particles, the pH response nano particles expose positive charges and the like are utilized, the nano particles are innovatively combined with the ion channel, and a new thought for promoting healing of the diabetic wound is provided.

Description

Technical Field

[0001] The present application relates to a composite microneedle material and a preparation method and application thereof, belonging to the field of biomaterials and medicine. Background Art

[0002] Diabetes and its complications pose a great threat to human life and health. Among them, high blood sugar in diabetic wounds can cause severe inflammation in the wounds and make them difficult to heal. The biofilm formed by bacteria attached to the surface of injured tissues is 10 to 1000 times more resistant to antibiotics than planktonic bacteria, which brings great pain to patients with diabetic wounds. At present, it is difficult to achieve a comprehensive therapeutic effect with simple anti-inflammatory drugs. The investigation found that microneedles can destroy bacterial biofilms and effectively deliver drugs, but the current microneedles have poor intelligent responsiveness and are difficult to release drugs on demand. In addition, cells, as a complex network system composed of multiple signaling pathways, pose a huge challenge to the regulation of cell signaling pathways. Therefore, there is an urgent need to develop an intelligent dual-responsive microneedle to target and remove bacteria in diabetic wounds, achieve precise regulation of multiple cell signaling pathways, inhibit inflammatory responses, and provide an effective strategy for the treatment of diabetic wounds. Summary of the invention

[0003] According to one aspect of the present application, a composite microneedle material is provided, wherein the tip of the composite microneedle material is a composite hydrogel of pH-responsive photothermal conjugated polymer nanoparticles, and the substrate is hyaluronic acid. The composite microneedle is attached to the wound surface of diabetic mice, and in the microenvironment of bacterial-infected diabetic wounds, the nanoparticles are released to disintegrate the bacterial biofilm, and at the same time, the TRPV1 ion channel is photothermally activated to promote Ca 2+ Influx of proteins regulates the phosphatidylinositol 3-kinase / threonine protein kinase (PI3K / Akt) signaling pathway, thereby activating the eNOS / NO signaling pathway, increasing the level of NO, promoting angiogenesis, reducing inflammatory response, and accelerating diabetic wound healing; it is of great significance to reveal the effective treatment mechanism of diabetic wounds.

[0004] The composite microneedle material comprises a needle tip and a substrate; wherein the needle tip is a composite hydrogel loaded with nanoparticles; the nanoparticles are pH-responsive photothermal conjugated polymer nanoparticles; and the substrate is hyaluronic acid.

[0005] As one specific embodiment, the composite microneedle can respond to the ROS level in diabetic wounds, and the composite microneedle material is composed of PVA and nanoparticles as needle tips, and hyaluronic acid (HA) as a substrate; wherein the nanoparticles are self-assembled by amphiphilic polymers in aqueous solution, and CHO-PEG-CHO is modified on the surface to form nanoparticles that respond to the low pH level of infected diabetic wounds. More specifically, the needle tip component also includes TSPBA.

[0006] Optionally, the nanoparticles have pH and photothermal responses.

[0007] Optionally, the diameter of the nanoparticle is 150-250 nm; preferably, the diameter of the nanoparticle is 200 nm.

[0008] Optionally, the composite hydrogel is TSPBA-PVA hydrogel.

[0009] As a specific embodiment, the nanoparticles include but are not limited to the following structures:

[0010]

[0011] In the formula, a+b=1, n represents the degree of polymerization, and n=10-100.

[0012] Where R is the following group

[0013]

[0014] Wherein X=10-50, Y=1-50.

[0015]

[0016] As shown above, a polymer (DPP-BBT) is obtained through a series of nucleophilic substitution reactions based on diketopyrrolopyrrole (DPP) units, and the polymer side chains are modified by click reactions to obtain nanoparticles. Subsequently, a large number of positive charges on the surface of the nanoparticles are shielded by introducing Schiff base bonds.

[0017] Optionally, the microneedle substrate has a thickness of 1.5 to 2.5 MM, a needle body height of 600 to 700 μm, a base diameter of 250 to 350 μm, and a needle spacing of 750 to 850 μm.

[0018] Optionally, the microneedle has a substrate thickness of 2.5 MM, a needle body height of 600 μm, a base diameter of 300 μm, and a needle spacing of 680 μm.

[0019] Optionally, the composite microneedle material is a ROS and pH dual-responsive composite microneedle material.

[0020] Another aspect of the present application provides a method for preparing the composite microneedle material according to any one of the above items, the method comprising:

[0021] The composite hydrogel containing nanoparticles is placed in a microneedle mold for treatment; then raw material B containing a substrate is added and molded to obtain the composite microneedle material.

[0022] In this application, the photothermal conjugated polymer composite microneedle effectively penetrates the biofilm through the microneedle head, disintegrates the bacteria inside the biofilm, and improves the permeability of nanoparticles in the biofilm. Under near-infrared light irradiation, photothermal release of nanoparticles inhibits the bacterial quorum sensing system, destroys the cell membrane of Staphylococcus aureus, inhibits the metabolic cycle of bacteria, causes bacterial death, regulates TRPV1 ion channels, relieves inflammatory responses, promotes angiogenesis, and synergistically accelerates the healing of diabetic wounds.

[0023] Under the irradiation of near-infrared light, the composite microneedle generates heat to activate TRPV1 ion channels, causing intracellular Ca 2+ Increased concentration activates Ca 2+ It depends on the PI3K / Akt signaling pathway, increases the production of intracellular NO, activates endothelial nitric oxide synthase (eNOS), and thus activates the eNOS / NO pathway, promoting diabetic wound healing by accelerating angiogenesis and inhibiting inflammatory response.

[0024] Optionally, the composite hydrogel is obtained by mixing a raw material I containing TSPBA and a raw material II containing PVA and nanoparticles to obtain the composite hydrogel.

[0025] Optionally, the concentration of TSPBA in the raw material I is 3-8wt%; the concentration of PVA in the raw material II is 8-12wt%; and the volume ratio of the raw material I to the raw material II is 1:2-4.

[0026] Optionally, the concentration of TSPBA in the raw material I is 5wt%; the concentration of PVA in the raw material II is 10wt%.

[0027] Optionally, the volume ratio of the raw material I to the raw material II is 1:3.

[0028] As one specific embodiment, the method for obtaining the composite hydrogel includes:

[0029] The 10 wt % PVA solution was mixed with the nanoparticle solution in equal volumes, and then mixed with the 5 wt % TSPBA solution in a ratio of 3:1 to prepare a 5 wt % system of RR-PVA.

[0030] Optionally, the method for obtaining the microneedle includes: placing the composite hydrogel in a microneedle mold for solidification, and then adding a raw material B containing hyaluronic acid and / or hyaluronate, and molding to obtain the composite microneedle material.

[0031] Optionally, the treatment includes: placing the composite hydrogel in a microneedle mold, removing bubbles, and drying after centrifugation.

[0032] Optionally, the adding of raw material B containing a substrate comprises: placing the composite hydrogel in a microneedle mold and drying it, and when the composite hydrogel is dried in the microneedle mold until it is about to be exposed from the mold, adding the raw material B, and drying to obtain the microneedle.

[0033] As one specific embodiment, the method for obtaining the microneedle includes: adding the composite hydrogel (RR-PVA hydrogel) dropwise into the microneedle mold, placing the mold in a vacuum environment created by a vacuum pump for negative pressure degassing; then scraping off the bubbles on the surface of the hydrogel, placing it in a homemade centrifuge device for centrifugation (for example, centrifuging at 800 rpm for 20 minutes), taking it out and drying it; when the RR-PVA hydrogel is dry to the point of almost exposing the mold, adding 400 μL of a 4wt% hyaluronic acid solution and continuing to dry; when it is almost dry, adding the hyaluronic acid solution again, and completely drying to obtain the microneedle.

[0034] Optionally, the nanoparticles are assembled from amphiphilic conjugated polymers and then introduced with Schiff base bonds.

[0035] Optionally, the nanoparticles are obtained by self-assembly of an organic conjugated polymer consisting of a hydrophobic conjugated main chain and a hydrophilic side chain.

[0036] Optionally, the method for obtaining the nanoparticles comprises: obtaining a polymer through a nucleophilic substitution reaction based on a diketopyrrolopyrrole unit, modifying the polymer side chain through a click reaction to obtain nanoparticles, and then introducing a Schiff base bond through a reaction with the polymer side chain.

[0037] Optionally, the blending conditions include: vortex uniform mixing.

[0038] As one specific embodiment, the photothermal nanoparticle composite microneedle prepared in this application is mainly composed of photothermal conjugated polymer nanoparticles (NPs-CHO), composite hydrogel (RR-PVA) material, and hyaluronic acid (HA). The photothermal conjugated polymer nanoparticles are wrapped in the composite hydrogel, and RR-PVA is used as the needle body of the microneedle, which forms a microneedle patch with the hyaluronic acid substrate.

[0039] As one of the specific embodiments of the present application, the stimulus-responsive polymer is mostly an amphiphilic structure, which forms nanoparticles in water and can respond to external environments such as pH, light, temperature, molecules, electrolytes, voltage or other factors to produce specific response changes. These polymers have received extensive attention and application due to their unique properties. Amphiphilic conjugated polymers form nanoparticles by self-assembly, and then introduce aldehyde-encapsulated polyethylene glycol (CHO-PEG1000-CHO) on the surface of the nanoparticles. The Schiff base bond formed by polyethyleneimine and (CHO-PEG1000-CHO) on the surface of the nanoparticles can shield a large amount of positive charges on the surface of the nanoparticles, thereby improving biosafety. Due to the instability of the Schiff base bond under pH ≤ 6.8 in the bacterial microenvironment, polyethylene glycol is shed, exposing positive charges, thereby achieving targeting of bacteria and biofilms. In addition, since the nanoparticles have photothermal properties, under 880nm laser irradiation, the nanoparticles targeted on the bacterial membrane generate heat and ROS to achieve antibacterial properties.

[0040] In another aspect of the present application, a composite microneedle patch is provided, comprising at least one of the composite microneedle materials described in any one of the above items and the composite microneedle materials prepared according to any one of the above methods.

[0041] Another aspect of the present application provides the use of any of the above-mentioned composite microneedle materials and / or at least one of the composite microneedle materials prepared according to any of the above-mentioned methods and / or the composite microneedle patch in the preparation of a drug for promoting diabetic wound healing.

[0042] In diabetic wound care, Ca 2+ As an important second messenger in the body, it mainly enters the cell through ion channels to initiate signal transduction pathways, among which transient receptor potential (TRP) ion channels are Ca 2+ A major player in signal transduction that regulates Ca 2+ Signal transduction regulates cell physiological functions. Studies have shown that at 43°C, by activating the TRPV1 ion channel of endothelial cells, Ca 2+ The PI3K / Akt signaling pathway that is dependent on endothelial cells can inhibit the inflammatory response of endothelial cells. In addition, activating the TRPV1 ion channel of endothelial cells can increase the level of NO in cells, which can promote angiogenesis in cells on the one hand, and inhibit bacterial growth by reacting with bacterial DNA on the other hand, and prevent the repair of damaged DNA, which will provide an effective treatment for diabetic wound healing.

[0043] This application proposes to use the advantages of pH and photothermal responsive conjugated polymers to target bacteria and activate TRPV1 ion channels, ROS responsive microneedle patches for transdermal drug delivery, drug delivery efficiency, simple and fast operation, minimal harm to the human body, and efficient drug penetration to prepare stimulus-responsive conjugated polymer nanoparticle composite microneedles, use photothermal and photodynamic combined antibacterial effects, and regulate TRPV1 ion channels to effectively reduce inflammation in diabetic wounds, inhibit biofilms and eliminate pathogens in the wound site, provide a new strategy for the preparation of photothermal responsive device-based composite microneedles, and provide new ideas for regulating diabetic wound healing.

[0044] This application designs and synthesizes a series of conjugated polymers with good photothermal properties, uses them as the core to prepare water-soluble nanoparticles, and loads the nanoparticles on the needle tip of the microneedle to prepare photothermal conjugated polymer nanoparticle composite microneedles. The composite microneedles are attached to the wound surface of diabetic mice. In the microenvironment of diabetic wounds infected with bacteria, nanoparticles are released to reduce the level of inflammatory factors and disintegrate bacterial biofilms. At the same time, photothermal activation of TRPV1 ion channels promotes Ca 2+ Influx of NO regulates the phosphatidylinositol 3-kinase / threonine protein kinase (PI3K / Akt) signaling pathway, thereby activating the eNOS / NO signaling pathway, increasing the level of NO, promoting angiogenesis, reducing inflammatory response, and accelerating diabetic wound healing. This is of great significance for revealing the effective treatment mechanism of diabetic wounds. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 Schematic diagram of pH response of nanoparticles used in the composite microneedle material in Example 1.

[0046] Figure 2 This is the UV-visible absorption spectrum of the nanoparticles used in the composite microneedle material in Example 1.

[0047] Figure 3 This is a characterization diagram of the particle size of the composite microneedle material in Example 1.

[0048] Figure 4 This is the SEM image of the composite microneedle material in Example 1.

[0049] Figure 5 This is a laser confocal microscope imaging data diagram of the composite microneedle material in Example 1.

[0050] Figure 6 This is a data diagram of the mechanical properties of the composite microneedle material in Example 1.

[0051] Figure 7 This is a thermal imaging data diagram of the composite microneedle material on mice in Example 1.

[0052] Figure 8This is an imaging data diagram of the antibacterial gel of the composite microneedle material in Example 2.

[0053] Fig. 9 This is a patch clamp data diagram of the composite microneedle material regulating the TRPV1 channel in Example 3.

[0054] Fig.10 To implement Example 3, the composite microneedle material affects intracellular Ca 2+ Concentration data plot. DETAILED DESCRIPTION

[0055] The present application is described in detail below with reference to embodiments, but the present application is not limited to these embodiments.

[0056] Through implementation examples, the preparation method of the composite microneedle and its antibacterial effect and regulation of TRPV1 channels to reduce inflammatory response and promote angiogenesis are explained.

[0057] Unless otherwise specified, the experimental methods used in the following examples are all conventional methods; the reagents, biological materials, etc. used in the following examples are all commercially available unless otherwise specified.

[0058] The preparation of the photothermal microneedle material for promoting diabetic wound healing in this application is mainly composed of three parts: photothermal conjugated polymer nanoparticles, RR-PVA material, and HA. The composite hydrogel material is used as the needle body of the microneedle, and a microneedle patch is formed with a hyaluronic acid substrate. The photothermal conjugated polymer nanoparticles are wrapped in the composite hydrogel to prepare a photothermal conjugated polymer composite microneedle. The micro needle can effectively penetrate the biofilm, disintegrate the bacteria inside the biofilm, and improve the permeability of the nanoparticles in the biofilm. Under near-infrared light irradiation, photothermal release of nanoparticles inhibits the bacterial quorum sensing system, destroys the cell membrane of Staphylococcus aureus, inhibits the metabolic cycle of bacteria, and causes bacterial death. In addition, nanoparticles inhibit cell inflammation and promote angiogenesis. The composite microneedle material innovatively combines it with ion channels, photothermal and photodynamic antibacterial, and proposes a new idea for promoting diabetic wound healing. The microneedle patch penetrates the bacterial biofilm, remotely regulates the TRPV1 ion channel, and mediates intracellular Ca 2+ transduction, activating the PI3K / Akt signaling pathway, and subsequently activating the eNOS / NO signaling pathway, inhibiting inflammation, and synergistically inhibiting inflammation, providing a new strategy for disintegrating bacterial biofilms, synergistically inhibiting inflammation, and accelerating diabetic wound healing.

[0059] The conjugated polymer nanoparticles used in the following examples are synthesized by a series of nucleophilic substitution reactions and bromination reactions to obtain the target monomer quinone receptor unit DPP, introduce a BBT receptor unit with strong electron-withdrawing ability and a thiophene donor unit that helps to reduce the polymer band gap, and synthesize DPP-BBT by a palladium-catalyzed Stille coupling method. Finally, the nanoparticle material is obtained by self-assembly. The synthesis route of the nanoparticles and the pH response process are as follows: Figure 1 shown.

[0060] According to one embodiment of the present application, the method for preparing the composite microneedle comprises:

[0061] 1) 10 wt% PVA and nanoparticles were mixed in equal volumes.

[0062] 2) 5 wt % TSPBA solution was mixed with the solution in 1 above at a volume ratio of 1:3 and set aside.

[0063] 3) 400 μL of the above two solutions were added to the microneedle mold, and the mold was placed in a vacuum environment created by a vacuum pump for 1 min for negative pressure degassing.

[0064] 4) Scrape off the bubbles on the surface of the microneedle mold, place it in a homemade centrifuge and centrifuge it at 800 rpm for 20 min, then take it out and place it in a 37°C drying oven to dry.

[0065] 5) When the solution in the microneedles is dried to the point where the mold is almost exposed, add 400 μL of 4 wt % hyaluronic acid solution and continue drying.

[0066] 6) When it is almost dry, add 400 μL of 4 wt% hyaluronic acid solution again, continue to dry in a 37° C. drying oven, and after it is completely dry, separate the microneedle and the mold to obtain the microneedle.

[0067] Example 1

[0068] This embodiment provides a composite microneedle material (microneedle patch), which is mainly composed of three parts: photothermal conjugated polymer nanoparticles, RR-PVA material and HA. Among them, RR-PVA is used as the needle body material of the microneedle, and together with the hyaluronic acid substrate, it constitutes the microneedle patch. The photothermal conjugated polymer nanoparticles are encapsulated in the composite hydrogel to form a photothermal conjugated polymer composite microneedle.

[0069] The specific operation method of this implementation example is as follows:

[0070] (a) Dissolve 1 g of 4-(bromomethyl)phenylboronic acid in 40 mL of N,N-dimethylformamide (DMF), then add 0.2 g of N,N.N',N',-tetramethyl-1,3-propanediamine (TMPA), add a condenser and stir at 60°C for 24 h at a magnetic speed of 450 rpm. Pour 100 mL of tetrahydrofuran (THF) into the solution after the reaction, and the product TSPBA precipitates. Collect it by suction filtration and wash it three times with 20 mL of THF to obtain a colloid. Dry the washed TSPBA in a vacuum drying oven overnight to remove the organic solvent, then add water to dissolve it, freeze it and put it in a vacuum freeze drying oven for 2 days to obtain TSPBA white powder, which is sealed and stored at -20°C.

[0071] (b) Weigh 0.1 g of TSPBA powder and add 0.9 mL of ultrapure water to prepare a 10 wt% TSPBA solution. Low concentrations are prepared by diluting high concentrations and are prepared immediately before use. Weigh 1 g of PVA (14 kDa) and add it to 9 mL of ultrapure water, stir at 60°C to prepare a 10 wt% PVA solution.

[0072] (c) 10 wt% PVA was mixed with nanoparticles in equal volumes, and then the solution was mixed with 5 wt% TSPBA solution in a volume ratio of 3:1 for standby use. The hydrogel was then transferred to a microneedle mold and debubbled under vacuum.

[0073] (d) Scrape off the bubbles on the surface of the hydrogel, centrifuge at 800 rpm for 20 min, take out and place in a drying oven to dry.

[0074] (e) When the RR-PVA hydrogel is dried to the point where the mold is almost exposed, 400 μL of 4 wt% hyaluronic acid solution is added and the drying is continued. After complete drying, the microneedles are removed to form ROS and pH dual-responsive composite microneedles.

[0075] Figure 1 Schematic diagram of the pH response process of nanoparticles; the preparation process is that the polymer (DPP-BBT) and PEG-PEI self-assemble to form nanoparticles, and then assemble with CHO-PEG-CHO, and CHO and PEI form Schiff base bonds (which will break in the environment of diabetic wounds).

[0076] Take 200 μL of 25 μg / mL nanoparticle solution (water as solvent) and 200 μL of 15 μg / mL polymer solution (chloroform as solvent) and analyze the changes of characteristic peaks by UV-visible spectrophotometer. Both nanomaterials and polymers have UV absorption peaks at 880 nm ( Figure 2 ); The nanoparticle material was detected by dynamic light scattering, and the particle size of the nanoparticles was measured to be about 200nm ( Figure 3). The microneedle morphology was observed by SEM. The microneedle tips were neatly arranged and the tips were complete and sharp ( Figure 4 ). Figure 5 To observe the uniform distribution of photothermal conjugated polymer nanoparticles on the tip of the microneedle under laser confocal microscopy, it was proved that the composite microneedle was successfully prepared. Figure 6 The force-displacement curves of the microneedles within the range of 600 μm are shown, indicating that the microneedles have good mechanical properties. Figure 7 The thermal imaging of the microneedles inserted into the back of hair-removed db / db mice under 880nm laser irradiation shows that the microneedles can reach the activation temperature of TRPV1 43°C under laser irradiation without causing any damage to the mouse skin.

[0077] Example 2: Antibacterial application of composite microneedles

[0078] This embodiment is based on the fact that the photothermal conjugated polymer composite microneedle can effectively penetrate the biofilm through the microneedle head and disintegrate the bacteria inside the biofilm. The nanoparticles are released in the diabetic microenvironment, and heat is generated by near-infrared light irradiation to generate ROS. The photothermal and photodynamic combined antibacterial effects destroy the cell membrane of Staphylococcus aureus, inhibit the metabolic cycle of bacteria, and cause bacterial death.

[0079] The specific operation method of this implementation example is as follows:

[0080] (a) The nanoparticles have strong absorption at 880nm and are stimulus-responsive. The Schiff base structure on the side chain will break when entering the slightly acidic environment of the biomembrane, and a large number of amino groups on the surface of the nanoparticles will be exposed, revealing more positive charges to target the bacterial surface.

[0081] (b) The Staphylococcus aureus solution was centrifuged at 5000 rpm for 3 minutes. After centrifugation, the supernatant was discarded and then washed three times with sterile water. The OD of the bacterial solution was then 600 =1.

[0082] (c) The antibacterial effect was determined by antibacterial experiments. The concentration of nanoparticles was determined to be 25 μg / mL (the solvent was ultrapure water). 100 μL of bacterial solution was mixed with equal volumes of nanoparticle solution and sterile water, and then irradiated with a near-infrared 880 nm laser for 8 min. The irradiated bacterial solution was diluted 105 times, and 10 μL of the diluted bacterial solution was spread on LB solid culture medium with a pipette. The culture was placed in a constant temperature incubator overnight, and then photographed with a gel imager and the bacteria were counted ( Figure 8 ).from Figure 8 It can be seen that under the irradiation of near-infrared 880nm laser, nanoparticle materials can effectively disinfect Staphylococcus aureus.

[0083] Example 3: Composite microneedles regulate TRPV1 ion channels and related inflammatory signaling pathways to accelerate wound healing

[0084] This embodiment is a composite microneedle material. Under the irradiation of near-infrared light, the composite microneedle generates heat to activate the TRPV1 ion channel, causing intracellular Ca 2+ Increased concentration activates Ca 2+ It depends on the PI3K / Akt signaling pathway, increases the production of intracellular NO, activates eNOS, and thus activates the eNOS / NO pathway, promoting diabetic wound healing by accelerating angiogenesis and inhibiting inflammatory response.

[0085] The specific operation method of this implementation example is as follows:

[0086] (a) The whole-cell patch clamp technique was used to detect the current changes of TRPV1 ion channels in HUVEC cells to verify the regulation of ion channel function by microneedling; the operating conditions included: the patch clamp electrodes were made of borosilicate glass (Sutter Instruments, Novato, USA), drawn using a P-97 drawing instrument (Sutter Instruments, Novato, USA), and the electrode internal resistance was 3-5 MΩ. All currents were recorded by an EPC10 amplifier controlled by pulse software with a Digi LIH1600 (HEKA, Lambrecht, Germany) interface. Fig. 9 As shown, the composite microneedle material can significantly enhance the current of TRPV1 ion channel under the irradiation of near-infrared light, proving that the composite microneedle material has a good activation effect on TRPV1 ion channel.

[0087] Utilize Ca 2+ Indicators to monitor intracellular Ca 2+ The concentration change verifies the regulatory effect of microneedling on TRPV1 ion channel (the indicator is Rhod-2AM). Fig.10 As shown in the figure, under the irradiation of near-infrared light, the Ca in HUVEC cells treated with composite microneedle materials 2+ The fluorescence enhancement indicated that the microneedles activated TRPV1 ion channels and mediated the extracellular Ca 2+ A large amount of influx of proteins is achieved, thus regulating the TRPV1 ion channel-related signaling pathways.

[0088] The above are only a few embodiments of the present application and do not constitute any form of limitation to the present application. Although the present application is disclosed as above with preferred embodiments, it is not intended to limit the present application. Any technician familiar with the profession, without departing from the scope of the technical solution of the present application, using the technical content disclosed above to make slight changes or modifications are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A composite microneedle material, characterized in that: The composite microneedle material comprises a needle tip and a substrate; wherein the needle tip is a composite hydrogel loaded with nanoparticles; The nanoparticles are pH-responsive photothermal conjugated polymer nanoparticles; The base is hyaluronic acid.

2. The composite microneedle material according to claim 1, characterized in that: The needle tip of the composite microneedle material includes PVA and nanoparticles, and hyaluronic acid is used as a substrate; The nanoparticles are self-assembled by amphiphilic polymers in aqueous solution, and CHO-PEG-CHO is modified on their surface; The diameter of the nanoparticles is 150-250 nm.

3. The composite microneedle material according to claim 1, characterized in that: The microneedle base thickness is 1.5-2.5 MM, the needle body height is 600-700 μm, the base diameter is 250-350 μm, and the needle spacing is 750-850 μm; Preferably, the composite microneedle material is a ROS and pH dual-responsive composite microneedle material; Preferably, the microneedle substrate has a thickness of 2.5 MM, a needle body height of 600 μm, a base diameter of 300 μm, and a needle spacing of 680 μm.

4. The method for preparing the composite microneedle material according to any one of claims 1 to 3, characterized in that: The method comprises: The composite hydrogel containing nanoparticles is placed in a microneedle mold for treatment; then raw material B containing a substrate is added and molded to obtain the composite microneedle material.

5. The preparation method according to claim 4, characterized in that: The method for obtaining the composite hydrogel comprises: mixing a raw material I containing TSPBA and a raw material II containing PVA and nanoparticles to obtain the composite hydrogel; The concentration of TSPBA in the raw material I is 3-8 wt %; the concentration of PVA in the raw material II is 8-12 wt %; the volume ratio of the raw material I to the raw material II is 1:2-4; Preferably, the concentration of TSPBA in the raw material I is 5wt%; the concentration of PVA in the raw material II is 10wt%; The volume ratio of the raw material I to the raw material II is 1:

3.

6. The preparation method according to claim 4, characterized in that: The treatment comprises: placing the composite hydrogel in a microneedle mold, removing bubbles, centrifuging and then drying.

7. The preparation method according to claim 4, characterized in that: The adding of the raw material B containing the substrate comprises: when the composite hydrogel is dried in the microneedle mold until it is about to be exposed from the mold, adding the raw material B, and drying to obtain the composite microneedle material.

8. The preparation method according to claim 4, characterized in that: The nanoparticles are assembled from amphiphilic conjugated polymers and then introduced with Schiff base bonds; Preferably, the nanoparticles are obtained by self-assembly of an organic conjugated polymer consisting of a hydrophobic conjugated main chain and a hydrophilic side chain; Preferably, the method for obtaining the nanoparticles comprises: obtaining a polymer through a nucleophilic substitution reaction based on a diketopyrrolopyrrole unit, modifying the polymer side chain through a click reaction to obtain nanoparticles, and then introducing a Schiff base bond through a reaction with the polymer side chain.

9. A composite microneedle patch, characterized in that: Contains at least one of the composite microneedle material according to any one of claims 1 to 3 and the composite microneedle material prepared according to the method according to any one of claims 4 to 8.

10. Use of the composite microneedle material according to any one of claims 1 to 3 and / or at least one of the composite microneedle materials prepared according to the method according to any one of claims 4 to 8 and / or the composite microneedle patch according to claim 9 in the preparation of a drug for promoting diabetic wound healing.

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