Aggregation-induced emission metal organic framework nanoparticles and microneedle patch for accelerating healing of diabetic wounds as well as preparation method and application of aggregation-induced emission metal organic framework nanoparticles and microneedle patch

Abstract

The invention discloses aggregation-induced emission metal organic framework nanoparticles and microneedle patches for accelerating healing of diabetic wounds and a preparation method and application of the nanoparticles and the microneedle patches. The nanoparticles comprise aggregation-induced emission metal organic frameworks composed of aggregation-induced emission compounds and metal zinc ions, the carbon monoxide release precursor and the AIE photosensitizer TTI-COOH are loaded in the aggregation-induced emission metal organic framework, and the amphiphilic polymer wraps the aggregation-induced emission metal organic framework; the microneedle patch comprises a substrate layer and a needle body layer, and has the advantages that the microneedle patch has various biological functional characteristics of good biocompatibility, antibacterial property, anti-inflammatory property, oxidation resistance, cell migration promotion and angiogenesis promotion, and has good moisture absorption performance and mechanical property.

Description

Technical Field

[0001] The present invention relates to the field of developing new nano-drugs for treating diabetic wounds, and particularly relates to a preparation method and application of a multifunctional aggregation-induced emission metal-organic framework nanoparticle bilayer hydrogel microneedle patch. Background Art

[0002] Diabetes is a complex chronic metabolic disease. The number of diabetic patients globally has exceeded 500 million, and it is expected that its incidence rate will continue to increase for a long time in the future. Diabetic wounds are one of the most common complications of diabetic patients, featuring chronicity and intractability. They seriously affect the lives of patients, increase the amputation rate and mortality of patients, and cause serious health and economic burdens globally. The main reasons for the difficulty in healing diabetic wounds are that hyperglycemia causes vascular lesions, preventing normal nutrient transport and oxygen supply, resulting in wound necrosis; hyperglycemia provides a good growth environment for bacteria, and continuous bacterial infection is also an important reason for the difficulty in healing diabetic wounds; in addition, the hyperglycemic environment upregulates the expression of pro-inflammatory factors and generates a high level of oxidative stress, leading to difficulty in wound healing. These factors hinder the progress of the four stages of normal wound healing (hemostasis stage, inflammation stage, proliferation stage, and tissue remodeling stage), thus forming intractable wounds.

[0003] Currently, the main treatment methods for diabetic wounds are blood glucose control, surgical debridement, skin grafting, intelligent wound dressings, hyperbaric oxygen therapy, and using antibiotics to control infection. However, these methods are expensive, have a single function, are complex to operate, are prone to cause secondary injuries, and have limited treatment effects. In recent years, the application of nanoparticle drugs in treating diabetic wounds has received extensive attention, and there have been continuous relevant literature reports. However, most drugs have a single function and cannot comprehensively address the various pathogenic mechanisms of the difficulty in healing diabetic wounds. Therefore, there is an urgent need to develop new drugs for treating diabetic wounds with multiple functions, simple operation, and low cost.

[0004] Regarding the problem of continuous bacterial infection in diabetic wounds, antibiotics are mostly used clinically, but long-term use is prone to cause drug resistance problems. Photodynamic therapy (PDT) for antibacterial can avoid drug resistance problems. It has a broad antibacterial spectrum and is effective not only against bacteria but also against fungi, viruses, and parasites. Photodynamic therapy for antibacterial mainly generates reactive oxygen species (ROS) by light source excitation of photoactivated chemical substances (photosensitizers) to kill bacteria. Aggregation-induced emission materials (AIEgens) are a new type of photosensitizer, which have the characteristics of enhanced luminescence and higher ROS generation in the aggregated state, and are ideal candidate drugs for treating drug-resistant bacterial infections.

[0005] Exogenous CO is generally considered a toxic gas, but recent studies have demonstrated that it plays a variety of important biological roles in the pathogenesis of numerous diseases. CO exerts potent anti-inflammatory effects in conditions such as ischemia-reperfusion injury, lipopolysaccharide-induced organ damage, and inflammatory bowel disease. Furthermore, CO has been shown to have important biological functions in relaxing blood vessels and controlling the proliferation of vascular smooth muscle cells and endothelial cells. CO has also been reported to improve the success rate of flap transplantation and promote bone regeneration. Despite these advantages, gaseous CO molecules readily diffuse randomly, lacking target selectivity and dose control. Manganese dioxide decacarbonyl (MnCO) is an excellent CO-releasing prodrug with safe and controllable properties. It can release CO through a Fenton-like reaction in the presence of high levels of hydrogen peroxide, which coincides with the microenvironment of diabetic wounds and holds great promise for application. However, random diffusion, poor solubility, potential toxicity, and the lack of on-demand CO release in deep tissues continue to limit their practical applications. Nano-drug delivery systems hold promise for addressing these challenges.

[0006] Metal-organic frameworks (MOFs) are crystalline porous materials formed by metal ions or clusters linked to organic ligands through coordination bonds. They have a controllable structure, large porosity, and large specific surface area. They possess excellent adsorption and storage properties, and can enhance the biocompatibility of drug monomers. Therefore, they hold great promise for application in nano-drug delivery systems. However, MOFs' poor water solubility and tissue permeability limit their application in wound treatment.

[0007] Hydrogel microneedle patches are an excellent transdermal drug delivery system that can transport drugs to the dermis and enhance their therapeutic effects. Hyaluronic acid (HA), a substance derived from the human or animal body, is a major component of the extracellular matrix and possesses excellent biocompatibility, water absorption, biodegradability, and certain mechanical properties. HA can also enhance collagen deposition, epithelialization, and wound angiogenesis, so choosing HA as the raw material for microneedle patches is beneficial for wound healing. Mixing γ-polyglutamic acid (γ-PGA) with ethylene glycol diglycidyl ether (EGDE) forms a strongly cross-linked hydrogel with excellent water absorption and moisturizing properties, which is beneficial for wound healing. Summary of the Invention

[0008] The purpose of the present invention is to provide aggregation-induced luminescence metal-organic framework nanoparticles, microneedle patches, preparation methods and applications that accelerate the healing of diabetic wounds, so as to solve problems such as bacterial infection, oxidative stress, persistent inflammation, re-epithelialization disorders and angiogenesis disorders during the healing process of diabetic wounds.

[0009] In order to achieve the above object, the present invention adopts the following technical solutions:

[0010] An AIE photosensitizer named TTI-COOH has a structure as shown in formula (I):

[0011]

[0012] The present invention also provides a preparation method of the AIE photosensitizer. The process includes: under the protection of an inert gas, dissolving 5-(4-(diphenylamino)phenyl)thiophene-2-carbaldehyde and 1-(2-carboxyethyl)-2,3,3-trimethyl-3H-indolium-1-bromide in a solvent, adding piperidine, stirring overnight at 70 °C, concentrating to obtain a crude product, and purifying and eluting to obtain a purple powdery product, which is TTI-COOH.

[0013] Further, the process includes: under the protection of nitrogen, dissolving 355 mg of 5-(4-(diphenylamino)phenyl)thiophene-2-carbaldehyde and 249 mg of 1-(2-carboxyethyl)-2,3,3-trimethyl-3H-indolium-1-bromide in a mixed solvent of 15 mL of chloroform and 15 mL of ethanol, adding a drop of piperidine, stirring overnight at 70 °C, concentrating under reduced pressure to obtain a crude product, purifying and eluting to obtain a purple powdery product, which is TTI-COOH.

[0014] The present invention also provides aggregation-induced emission metal-organic framework nanoparticles for accelerating diabetic wound healing by applying the AIE photosensitizer, which include an aggregation-induced emission metal-organic framework composed of an aggregation-induced emission compound and metal zinc ions, a carbon monoxide-releasing precursor and the AIE photosensitizer TTI-COOH loaded inside the aggregation-induced emission metal-organic framework, and an amphiphilic polymer wrapped outside the aggregation-induced emission metal-organic framework.

[0015] The present invention also provides a preparation method of the aggregation-induced emission metal-organic framework nanoparticles for accelerating diabetic wound healing. The steps include: heating and stirring an aggregation-induced emission compound and a zinc salt as raw materials to synthesize an aggregation-induced emission metal-organic framework; mixing and stirring the aggregation-induced emission metal-organic framework and a carbon monoxide-releasing precursor, then mixing and stirring with the AIE photosensitizer, and finally dropping the mixture into an amphiphilic polymer solution and mixing and stirring to obtain the target product.

[0016] Further, the steps include:

[0017] Weigh 0.05 g of tetrakis(4-carboxybiphenyl)ethylene and dissolve it in 30 mL of DMF. Weigh 0.54 g of zinc acetate and dissolve it in 30 mL of pure water. Add them together into a reaction vessel, stir and reflux at 120 °C for 10 min, add 2 mL of 10 M KOH to adjust the pH of the reaction system to above 9, maintain an alkaline atmosphere and continue heating and refluxing for 6 h. After the reaction is completed, cool to room temperature, centrifuge at 8000 rpm for 3 min, discard the supernatant, and resuspend the precipitate with pure water to obtain a suspension of the aggregation-induced emission metal-organic framework;

[0018] Take 2 mL of the aggregation-induced emission metal-organic framework suspension and centrifuge it at 8000 rpm for 3 min. Discard the supernatant, add 1 mL of H2O and 1 mL of DMF, mix well, place it in a glass bottle, add 0.008 g of MnCO dissolved ultrasonically in 200 μL of DMF, and stir at room temperature overnight; then centrifuge the solution at 8000 rpm for 3 min, resuspend the precipitate with 2 mL of pure water, place it in a 500 Da dialysis bag, and dialyze for more than 12 h to obtain an aggregation-induced emission metal-organic framework suspension loaded with dimanganese decacarbonyl;

[0019] Dissolve 2 mg of TTI-COOH in 1 mL of DMSO to prepare a 3.09 mM TTI-COOH solution, and then dilute it with pure water to a 2 mM TTI-COOH solution; centrifuge 1 mL of the aggregation-induced emission metal-organic framework suspension loaded with dimanganese decacarbonyl at 8000 rpm for 3 min, discard the supernatant, resuspend the precipitate with 1 mL of a 2 mM TTI-COOH solution, and stir overnight; then centrifuge at 8000 rpm for 3 min, dissolve the precipitate with 1 mL of pure water, and dialyze it with an 800 Da dialysis bag to obtain an aggregation-induced emission metal-organic framework suspension loaded with both dimanganese decacarbonyl and TTI-COOH;

[0020] Dissolve BSA powder in ultrapure water to prepare a 5 mg / mL BSA solution. Take 1 mL of the aggregation-induced emission metal-organic framework suspension loaded with both dimanganese decacarbonyl and TTI-COOH, centrifuge it at 8000 rpm for 3 min, then discard the supernatant, and resuspend the precipitate with 1 mL of DMSO to make it evenly dispersed; place 9 mL of the BSA solution in a container, and dropwise add the aggregation-induced emission metal-organic framework loaded with dimanganese decacarbonyl and TTI-COOH suspended in DMSO under high-speed stirring at 1000 rpm, and stir overnight to obtain the aggregation-induced emission metal-organic framework nanoparticles for accelerating diabetic wound healing.

[0021] The present invention also provides an application of the aggregation-induced emission metal-organic framework nanoparticles for accelerating diabetic wound healing in the preparation of a drug for treating diabetic wounds.

[0022] The present invention also provides a double-layer hydrogel microneedle patch applying the aggregation-induced emission metal-organic framework nanoparticles for accelerating diabetic wound healing, which includes a base layer and a needle body layer in contact with the wound surface. The needle bodies of the needle body layer are arranged in an array on the base layer. The base layer is formed by γ-PGA and ethylene glycol diglycidyl ether; the needle body layer is formed by hyaluronic acid loaded with the aggregation-induced emission metal-organic framework nanoparticles for accelerating diabetic wound healing.

[0023] The present invention also provides a method for preparing a bilayer hydrogel microneedle patch of the aggregation-induced emission metal-organic framework nanoparticles for accelerating diabetic wound healing. The process includes: mixing an aqueous solution of the aggregation-induced emission metal-organic framework nanoparticles for accelerating diabetic wound healing with hyaluronic acid, and after stirring evenly, filling it into the needle body part of a PDMS microneedle mold; mixing γ-PGA and ethylene glycol diglycidyl ether, and adjusting the pH, then filling this solution into the base layer part of the PDMS microneedle mold; drying the mold at room temperature and then demolding to obtain the bilayer hydrogel microneedle patch of the aggregation-induced emission metal-organic framework nanoparticles for accelerating diabetic wound healing.

[0024] The present invention also provides a method for preparing a bilayer hydrogel microneedle patch of the aggregation-induced emission metal-organic framework nanoparticles for accelerating diabetic wound healing. The detailed process includes: weighing 250 mg of hyaluronic acid, dissolving it with 1 mL of a suspension of the aggregation-induced emission metal-organic framework nanoparticles for accelerating diabetic wound healing with a concentration of 15 μg / mL, adding it to a PDMS microneedle mold, centrifuging at 3000 rpm for 3 min to remove air bubbles, rotating the centrifuge tube 180° and then centrifuging again to fully fill the needle body part with the liquid and remove the excess solution on the surface; then preparing a 12% wt γ-PGA and ethylene glycol diglycidyl ether aqueous solution, weighing 60 mg of γ-PGA, adding 420 μL of H2O, 21.45 μL of ethylene glycol diglycidyl ether, and 2 μL of concentrated hydrochloric acid to adjust the pH = 4, stirring and mixing evenly, then spreading it over the surface of the PDMS microneedle mold, centrifuging at 3000 rpm for 3 min to remove air bubbles; finally, placing the filled mold in a sealed drying container at room temperature and drying for 6 h and then demolding to obtain the bilayer hydrogel microneedle patch of the aggregation-induced emission metal-organic framework nanoparticles for accelerating diabetic wound healing.

[0025] The advantages of the present invention include: The aggregation-induced emission metal-organic framework nanoparticles for accelerating diabetic wound healing have multiple biological functional characteristics such as good biocompatibility, antibacterial, anti-inflammatory, antioxidant, promoting cell migration, and promoting angiogenesis.

[0026] The TTI-COOH in the aggregation-induced emission metal-organic framework nanoparticles for accelerating diabetic wound healing endows it with the property of photodynamic sterilization, mainly targeting Staphylococcus aureus and methicillin-resistant Staphylococcus aureus during the healing process of infectious diabetic wounds.

[0027] The aggregation-induced emission metal-organic framework nanoparticles for accelerating diabetic wound healing have antioxidant and anti-inflammatory biological functions, mainly relying on the Fenton-like reaction of decacarbonyldimanganese with high levels of hydrogen peroxide in the diabetic wound microenvironment, thereby reducing the peroxide level, while generating carbon monoxide, realizing the transformation of inflammatory macrophages into anti-inflammatory macrophages, reducing the level of inflammatory factors, increasing the level of anti-inflammatory factors, thereby shortening the inflammatory period, promoting the migration of human umbilical vein endothelial cells, promoting the formation of tubules by human umbilical vein endothelial cells, and accelerating the healing of diabetic wounds.

[0028] Utilizing the mechanical property of the double-layer microneedle patch to penetrate the skin can ensure the release of the aggregation-induced emission metal-organic framework nanoparticles loaded in the double-layer microneedle patch into the dermis layer, enhancing the tissue permeability of the nanoparticle drug and improving the drug efficacy, which greatly enhances the effect. Utilizing the moisture absorption property of the double-layer microneedle patch can remove the tissue exudate from the wound, which has practical value for promoting the healing of infectious diabetic wounds.

[0029] The present invention is ingeniously designed and simple in composition, and can effectively regulate multiple aspects in the process of diabetic wound healing, ultimately promoting the healing of diabetic wounds. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The drawings described herein are used to provide a further understanding of the present invention, form a part of this application, and do not constitute an improper limitation to the present invention. In the drawings:

[0031] Figure 1 is the nuclear magnetic resonance hydrogen spectrum of TTI-COOH;

[0032] Figure 2 is the nuclear magnetic resonance carbon spectrum of TTI-COOH;

[0033] Figure 3 is the mass spectrum of TTI-COOH;

[0034] Figure 4 is the scanning electron microscope image of BSA-coated T / MnCO@AMOF;

[0035] Figure 5 is the transmission electron microscope image of BSA-coated T / MnCO@AMOF;

[0036] Figure 6 is the energy-dispersive X-ray elemental analysis map of BSA-coated T / MnCO@AMOF;

[0037] Figure 7 is the ultraviolet-visible absorption spectral curve graph of each nanoparticle and chemical molecule;

[0038] Figure 8It is the fluorescence spectrum curve diagram of each nanoparticle;

[0039] Figure 9 It is the Fourier transform infrared spectrum diagram of each nanoparticle and chemical molecule;

[0040] Figure 10 It is the particle size distribution diagram of each nanoparticle;

[0041] Figure 11 It is the zeta potential diagram of each nanoparticle;

[0042] Figure 12 It is the ultraviolet-visible absorption spectrum curve diagram of different concentrations of TTI-COOH and T / MnCO@AMOF;

[0043] Figure 13 It is the diagram explaining the photodynamic characteristics of T / MnCO@AMOF: Figure 13 A is the ultraviolet-visible absorption spectrum curve diagram of ABDA in the aqueous solution of T / MnCO@AMOF changing with time; Figure 13 B is the ultraviolet-visible absorption spectrum curve diagram of pure aqueous solution changing with time;

[0044] Figure 14 It is the ultraviolet-visible absorption spectrum curve diagram for detecting the release of CO by T / MnCO@AMOF in the H2O2 environment using Hb: Figure 14 A is the ultraviolet-visible absorption spectrum curve of Hb changing with time in the presence of T / MnCO@AMOF; Figure 14 B is the ultraviolet-visible absorption spectrum curve of Hb changing with time in the absence of T / MnCO@AMOF;

[0045] Figure 15 It is the characterization diagram of the T / MnCO@AMOF double-layer hydrogel microneedle patch: Figure 15 A is the force-displacement curve diagram for testing the mechanical properties of the microneedle patch; Figure 15 B is the curve diagram of the water absorption and swelling rate of the base layer hydrogel changing with time; Figure 15 C is the morphological diagram of the microneedle patch in the normal state under the microscope; Figure 15 D is the morphological diagram of the microneedle patch under the microscope 10 minutes after puncturing the skin of C57 mice;

[0046] Figure 16 It is the result diagram of detecting the biocompatibility of T / MnCO@MOF on RAW and HUVECs by the CCK-8 method;

[0047] Figure 17 It is the in vitro antibacterial effect diagram of T / MnCO@AMOF: Figure 17 A is the result diagram of the antibacterial effect coating plate on S. aureus and MRSA; Figure 17B is the growth curve of antibacterial effect against S. aureus and MRSA;

[0048] Figure 18 It is the in vitro antioxidant fluorescence detection diagram of T / MnCO@AMOF;

[0049] Figure 19 It is the result diagram of detecting the relative expression levels of mRNA of genes related to in vitro inflammation and macrophage polarization of T / MnCO@AMOF by qPCR;

[0050] Figure 20 It is the result diagram of detecting the effect of T / MnCO@AMOF on the migration of HUVECs cells by cell scratch assay;

[0051] Figure 21 It is the result diagram of detecting the effect of T / MnCO@AMOF on the migration of HUVECs cells by Transwell assay;

[0052] Figure 22 It is the blood vessel imaging diagram of HUVECs grown on Matrigel after being stained with calcein after treatment with T / MnCO@AMOF;

[0053] Figure 23 It is the in vivo detection of the effect of T / MnCO@AMOF double-layer hydrogel microneedle patch on diabetic wound healing: Figure 23 A is the result diagram after plating the wound bacterial liquid on the 3rd day after establishing the infectious diabetic wound model; Figure 23 B is the diagram of wound healing within 14 days; Figure 23 C is the Masson and H&E staining diagrams of the skin tissue section of the wound healing on the 14th day;

[0054] Figure 24 It is the schematic diagram of the preparation process of the aggregation-induced emission metal-organic framework nanoparticle double-layer hydrogel microneedle patch for accelerating diabetic wound healing and the principle of accelerating diabetic wound healing. [[ID=3�]]Specific embodiments

[0055] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. Here, the illustrative embodiments and descriptions of the present invention are used to explain the present invention, but not to limit the present invention.

[0056] For the experimental methods without specific experimental conditions in the following examples, they are usually carried out according to conventional experimental conditions or according to the experimental conditions recommended by the manufacturer. The raw materials without specified preparation methods are commercially available products. The preparation processes of Examples 1 to 3 are as Figure 24 shown.

[0057] Example 1. Synthesis of TTI-COOH

[0058] In a nitrogen-filled glove box, 5-(4-(diphenylamino)phenyl)thiophene-2-carbaldehyde (355 mg, 1 mmol) and 1-(2-carboxyethyl)-2,3,3-trimethyl-3H-indolium-1-bromide (249 mg, 0.8 mmol) were dissolved in a mixed solvent of chloroform (CHCl3, 15 mL) and ethanol (EtOH, 15 mL) in a 50 mL round-bottom flask. Subsequently, a drop of piperidine was added. The reaction mixture was stirred overnight at 70 °C and then concentrated under reduced pressure. The crude product was purified by silica gel column chromatography, eluting with petroleum ether / dichloromethane (volume ratio 1:1) to obtain the purple powder product TTI-COOH (286 mg, yield 55%), which is an AIE photosensitizer.

[0059] Example 2. Synthesis of Aggregation-Induced Emission Metal-Organic Framework (AMOF)

[0060] Synthesis of AMOF: Weigh 0.05 g of tetrakis(4-carboxybiphenyl)ethylene (TCBE) (0.615 μmol) and dissolve it in 30 mL of DMF. Weigh 0.54 g of zinc acetate (2.46 μmol) and dissolve it in 30 mL of pure water. Then add them together into a round-bottom flask and stir magnetically while heating under reflux (120 °C, 10 min). Add 2 mL of 10 M KOH solution (5.6 g of KOH dissolved in 10 mL of H2O) to adjust the pH of the reaction system to above 9, and continue heating under reflux for 6 h while maintaining an alkaline atmosphere. After the reaction is completed, cool it to room temperature to obtain AMOF. Centrifuge at 8000 rpm for 3 min, discard the supernatant, and resuspend the precipitate with pure water to obtain an aggregation-induced emission metal-organic framework suspension.

[0061] Example 3. Synthesis of Aggregation-Induced Emission Metal-Organic Framework Nanoparticles (T / MnCO@AMOF) for Accelerating Diabetic Wound Healing

[0062] Synthesis of MnCO@AMOF: Take 2 mL of the aggregation-induced emission metal-organic framework suspension and centrifuge (8000 rpm, 3 min), discard the supernatant, add 1 mL of H2O and 1 mL of DMF, mix well and place it in a glass bottle. Then add 0.008 g of MnCO (first ultrasonically dissolve it in 200 μL of DMF), stir at room temperature overnight to obtain MnCO@AMOF. Then centrifuge the solution (8000 rpm, 3 min), resuspend the precipitate with 2 mL of pure water, place it in a 500 Da dialysis bag, and dialyze for more than 12 h to obtain an aggregation-induced emission metal-organic framework suspension loaded with dimanganese decacarbonyl.

[0063] Synthesis of T / MnCO@AMOF: Dissolve 2 mg of TTI-COOH (Mw = 648.14 g / mol) in 1 mL of DMSO to prepare a 3.09 mM TTI-COOH solution, and then dilute it with pure water to a 2 mM TTI-COOH solution. Centrifuge 1 mL of the aggregation-induced emission metal-organic framework suspension loaded with dimanganese decacarbonyl (8000 rpm, 3 min), discard the supernatant, resuspend the precipitate with 1 mL of 2 mM TTI-COOH solution, and stir overnight to obtain T / MnCO@AMOF. Then centrifuge (8000 rpm, 3 min), resuspend the precipitate with 1 mL of pure water, and dialyze it using an 800 Da dialysis bag to obtain an aggregation-induced emission metal-organic framework suspension loaded with both dimanganese decacarbonyl and TTI-COOH.

[0064] Synthesis of BSA-coated T / MnCO@AMOF: Dissolve BSA powder in ultrapure water to prepare a 5 mg / mL BSA solution. Take 1 mL of the aggregation-induced emission metal-organic framework suspension loaded with both dimanganese decacarbonyl and TTI-COOH and centrifuge (8000 rpm, 3 min), then discard the supernatant, and resuspend the precipitate with 1 mL of DMSO to make it evenly dispersed. Place 9 mL of the BSA solution in a glass bottle, and add the DMSO-suspended T / MnCO@AMOF dropwise under high-speed stirring (1000 rpm), and stir overnight to obtain the aggregation-induced emission metal-organic framework nanoparticles for accelerating diabetic wound healing.

[0065] The above preparation process is as Figure 24 shown.

[0066] Characterize the photosensitizer obtained in Example 1 and the nanoparticles obtained in Example 2 and Example 3:

[0067] (1) We designed and successfully prepared the AIE photosensitizer TTI-COOH according to the predetermined synthesis route, and its structure was satisfactorily characterized by nuclear magnetic resonance and mass spectrometry, as Figures 1 - 3 shown.

[0068] (2) Use a scanning electron microscope (SEM) to observe the final product BSA-coated T / MnCO@AMOF: The results are as Figure 4 shown. The SEM images show that the morphology of BSA-coated T / MnCO@AMOF is spherical, with non-uniform sizes, and the diameter is 200 - 400 nm.

[0069] (3) Use a transmission electron microscope (TEM) to observe the final product BSA-coated T / MnCO@AMOF: The results are as Figure 5The transmission electron microscope images shown indicate that a single T / MnCO@AMOF is spherical, with a diameter of about 20 nm, and the morphology of BSA-coated T / MnCO@AMOF is an irregular sphere, with non-uniform size, and a diameter of about 200 - 400 nm.

[0070] (4) Use energy-dispersive X-ray spectroscopy (EDS) to analyze the chemical elements in the end product BSA-coated T / MnCO@AMOF: The results are as Figure 6 shown. The EDS elemental analysis results show that the nanoparticles contain C, O, Zn, and Mn elements, indicating that dimanganese decacarbonyl has been successfully loaded into the metal-organic framework.

[0071] (5) Use a UV-visible spectrophotometer (UV-Vis) to analyze the characteristic absorption peaks of each compound and nanoparticle: The results are as Figure 7 shown. The UV-Vis absorption spectrum shows that TCBE has a characteristic absorption peak at 370 nm, TTI-COOH has a characteristic absorption peak at 570 nm, both AMOF and MnCO@AMOF retain the characteristic absorption peak of TCBE, and T / MnCO@AMOF has the characteristic absorption peaks of TCBE and TTI-COOH, indicating the successful synthesis of AMOF and T / MnCO@AMOF.

[0072] (6) Use a fluorescence spectrometer (FLD) to analyze the fluorescence main peaks of each nanoparticle: The results are as Figure 8 shown. The fluorescence emission spectrum (PL) shows that under 570 nm excitation, TTI-COOH emits at 735 nm, and the aggregation of T / MnCO@AMOF in aqueous solution enhances the fluorescence.

[0073] (7) Use a Fourier transform infrared spectrometer to analyze the molecular structures of each compound: The results are as Figure 9 shown. The Fourier transform infrared (FT-IR) spectrum shows characteristic peaks at 2000 cm -1 and 640 cm -1 corresponding to the C≡O and Mn-C bonds in MnCO and MnCO@AMOF, respectively. On the contrary, these peaks are absent in AMOF. This observation also confirms the successful incorporation of MnCO into the AMOF structure. In addition, the characteristic peak of -COOH in TTI-COOH at 1713 cm -1 can also be observed in T / MnCO@AMOF, indicating that TTI-COOH has been successfully loaded onto T / MnCO@AMOF.

[0074] (8) Use a DLS particle size analyzer to analyze the particle size of each nanoparticle: The results are as Figure 10As shown, according to the DLS particle size distribution curve, the particle sizes of AMOF, MnCO@AMOF, and T / MnCO@AMOF after being wrapped with BSA are all 200 - 400 nm.

[0075] (9) Analyze the Zeta potential of each nanoparticle using a Zeta potential detector: The results are as Figure 11 shown. The Zeta potential detection results show that the surface of AMOF has a negative potential, approximately -14.78 mV; the surface of MnCO@AMOF has a negative potential, approximately -15.30 mV; the surface of T / MnCO@AMOF has a negative potential, approximately -14.75 mV.

[0076] (10) Analyze the loading rate of TTI-COOH loaded onto MnCO@AMOF using a UV-visible spectrophotometer (UV-Vis): The results are as Figure 12 shown. By measuring the absorbance of different concentrations of TTI-COOH at 570 nm using UV-Vis, a standard curve of concentration versus absorbance is obtained. Extract the TTI-COOH in T / MnCO@AMOF using dichloromethane, then measure the absorbance, and substitute it into the standard curve to calculate the concentration of TTI-COOH in T / MnCO@AMOF. Compare it with the amount of TTI-COOH added to obtain a loading rate of 83.37%.

[0077] Example 4. Photodynamic properties of multifunctional aggregation-induced emission metal-organic framework nanoparticles

[0078] Add 7 μL of an ABDA solution with a concentration of 20 mM to 1 mL of pure water, then add T / MnCO@AMOF to make its final concentration 15 μg / mL. After mixing evenly, place it in a 1 mL cuvette. Use a UV spectrometer to measure the absorbance, then take out the solution and irradiate it with a 633 nm laser with a power of 600 mW / cm 2 and measure the change in absorbance every 1 min for a total of 10 min. The results are as Figure 13 shown in A. The characteristic absorption peak of ABDA in the experimental group containing T / MnCO@AMOF gradually decreases, with a decrease of approximately 70% in absorbance within 10 min. The results are as Figure 13 shown in B. The characteristic absorption peak of ABDA in the control group without T / MnCO@AMOF shows almost no change within 10 min, indicating that T / MnCO@AMOF can generate singlet oxygen under 633 nm laser irradiation and has a photodynamic effect, which can be used for sterilization.

[0079] Example 5. Detection of carbon monoxide released by multifunctional aggregation-induced emission metal-organic framework nanoparticles using hemoglobin

[0080] The conversion of hemoglobin (Hb) to carboxyhemoglobin (HbCO) was determined using a UV-Vis spectrophotometer, and the CO released by T / MnCO@AMOF in an H2O2 environment could be detected. Weigh 1 mg of Hb (Mw = 64.5 KD) and dissolve it in 10 mL of PBS (pH = 7.4) to prepare a hemoglobin solution with a concentration of 1.55 μM. Weigh 52.2 mg of Na2S2O4 powder and dissolve it in 1 mL of PBS (pH = 7.4) for immediate use to prepare a Na2S2O4 solution with a concentration of 3 M. Then, take 2 mL of the Hb solution and place it in a 4 mL cuvette. Add 20 μL of Na2S2O2 (final concentration 3 mM) solution, 6 μL of H2O2 (final concentration 30 μM), and T / MnCO@AMOF (final concentration 15 μg / mL), immediately seal the cuvette, and place it for UV-Vis detection to obtain the absorption spectrum. The results are as Figure 14 shown. Within 1 h, as time passed, it was observed that the characteristic absorption peak of Hb at 430 nm gradually shifted towards the characteristic absorption peak of HbCO at 410 nm, indicating that T / MnCO@AMOF could release CO in an H2O2 environment.

[0081] Example 6. Synthesis of a multifunctional aggregation-induced emission metal-organic framework nanoparticle double-layer hydrogel microneedle patch

[0082] Weigh 250 mg of HA (hyaluronic acid) (Mw = 10 KDa) and dissolve it in 1 mL of a 15 μg / mL suspension of T / MnCO@AMOF. Add it to a PDMS microneedle mold, centrifuge to remove air bubbles (3000 rpm, 3 min), rotate the centrifuge tube 180° and centrifuge again to fully fill the needle part of the mold with the liquid and remove the excess solution on the surface. Then prepare a 12% wt γ-PGA and ethylene glycol diglycidyl ether (EDGE) aqueous solution (γ-PGA Mw = 2000 kDa). The specific operation is to weigh 60 mg of γ-PGA, add 420 μL of H2O, 21.45 μL of EDGE, and 2 μL of concentrated hydrochloric acid to adjust the pH to 4, stir and mix evenly, and then spread it on the surface of the PDMS microneedle mold and centrifuge to remove air bubbles (3000 rpm, 3 min). Finally, place the filled mold in a closed dry container at room temperature for 6 h and then demold to obtain a double-layer hydrogel microneedle patch loaded with T / MnCO@AMOF.

[0083] The microneedle patch was placed on a texture analyzer to detect the mechanical properties of the microneedle patch. Specifically, the needle tips were facing upwards, and through the contact of the mechanical sensor, the longitudinal force was detected, the compression force and displacement were recorded, and a force-displacement curve was plotted. As shown in Figure 15A, there was a point with a sudden change in the force-displacement curve at 0.11 N, indicating the fracture of the needle tip, suggesting that the maximum mechanical strength of the needle tip was 0.11 N / needle, while only 0.058 N / needle of force was required to penetrate the skin stratum corneum. Therefore, the microneedles had sufficient mechanical strength to penetrate the skin stratum corneum.

[0084] The microneedle patch was pressed on the smooth skin of C57 mice and left for 10 min. The changes before and after the needle tip part of the microneedles were observed through a microscope. The results were as Figure 15 shown in C-D. The needle body part of the microneedles dissolved, indicating that the needle body part of the microneedle patch had good solubility.

[0085] One microneedle patch was taken, its initial mass was weighed, and it was immersed in pure water. The change in mass was recorded every 30 min until 7 h ended, and then the swelling rate was calculated. The results were as Figure 15 shown in B, indicating that the microneedle patch had excellent moisture absorption performance.

[0086] Example 7. Biological functions of the multifunctional aggregation-induced emission metal-organic framework nanoparticle double-layer hydrogel microneedle patch

[0087] (1) Biocompatibility: The CCK-8 method was used to evaluate the biocompatibility of T / MnCO@AMOF. T / MnCO@AMOF with concentrations of 0 μg / mL, 5 μg / mL, 10 μg / mL, 15 μg / mL, and 20 μg / mL was co-incubated with macrophages (RAW) or human umbilical vein endothelial cells (HUVECs) for 24 h, and the cell viability was detected by the CCK-8 method. The results were as Figure 16 shown. The survival rate of RAW after treatment with T / MnCO@AMOF at a concentration of 20 μg / mL and below was above 87%, and the survival rate of HUVECs was above 95%. This indicated that T / MnCO@AMOF had good biocompatibility.

[0088] (2) Photodynamic bactericidal property: Staphylococcus aureus (S. aureus) or methicillin-resistant Staphylococcus aureus (MRSA) was co-incubated with PBS, AMOF, TTI-COOH, and T / MnCO@AMOF respectively, and then irradiated with a 633 nm laser with a power of 600 mW / cm 2 for 10 min. Each group was set with a non-irradiated group as the control group. Then, the bacterial suspensions of each group were collected and inoculated on LB solid medium by the spread plate method, and the bacterial growth status was observed after overnight culture. The results were as Figure 17As shown in Figure A, it can be demonstrated that the TTI-COOH and T / MnCO@AMOF groups have a significant bactericidal effect under light irradiation. Additionally, the collected bacterial suspensions of each group were cultured in a liquid medium on a shaker, and the absorbance of each group at 600 nm was measured using UV-Vis at different time points (0 h, 3 h, 6 h, 9 h, and 12 h), and finally, the growth curves were plotted. The results are as Figure 17 shown in Figure B, which also indicates that the TTI-COOH and T / MnCO@AMOF groups have a significant bactericidal effect under light irradiation.

[0089] (3) Antioxidant properties: PBS, AMOF, MnCO@AMOF, and T / MnCO@AMOF were co-incubated with RAW cells respectively. After 6 h of co-incubation, the cells were then stimulated with 100 ng / mL lipopolysaccharide (LPS) for 24 h. The intracellular ROS levels of each group of cells were detected using the DCFH-DA probe. The cell nuclei were stained with Hoechest to localize the cell positions and evaluate the cell density, and the results were recorded by taking pictures with an inverted fluorescence microscope. The results are as Figure 18 shown, indicating that the MnCO@AMOF and T / MnCO@AMOF groups have a significant effect on reducing intracellular ROS.

[0090] (4) Anti-inflammatory properties: PBS, AMOF, MnCO@AMOF, and T / MnCO@AMOF were co-incubated with RAW cells respectively. After 6 h of co-incubation, the cells were then stimulated with 100 ng / mL lipopolysaccharide (LPS) for 24 h. The cells of each group were lysed with TRIzol reagent, and total RNA was extracted according to the manufacturer's instructions. Then, cDNA was synthesized using a reverse transcription kit. Using the synthesized cDNA as a template and the corresponding primers as the starting point, the mRNA levels of the inflammatory factor iNOS and the anti-inflammatory factors IL-10 and TGF-β in different groups of cells were quantitatively detected by qPCR. The results are as Figure 19 shown, indicating that MnCO@AMOF and T / MnCO@AMOF can inhibit the expression of inflammatory factors and enhance the expression of anti-inflammatory factors, and can regulate the transformation of macrophages from the inflammatory M1 type to the anti-inflammatory M2 type.

[0091] (5) Promoting cell migration properties: The promoting cell migration effects of MnCO@AMOF and T / MnCO@AMOF were verified by a cell scratch assay. The confluent HUVECs in a T25 cell culture flask were evenly distributed into four wells of a six-well plate. When the cell density reached more than 95%, a straight line was drawn in the center of each well of the six-well plate using a 200 μL pipette tip, and then the detached cells were washed away with PBS three times. DMEM medium containing 0.5% serum and 30 μM H2O2 was added, and PBS, AMOF, MnCO@AMOF, and T / MnCO@AMOF were added to each well respectively. The cultured cells were photographed at 0 h and 24 h respectively. The results are asFigure 20 As shown, it can be demonstrated that MnCO@AMOF and T / MnCO@AMOF have the effect of promoting cell migration.

[0092] In addition, the Transwell assay was used to verify the effect of MnCO@AMOF and T / MnCO@AMOF on promoting cell migration. The Transwell chamber was filled with 200 μL of DMEM medium without FBS and suspended with 2×10 4 HUVECs. The chamber was placed in a 24-well plate, and each well of the 24-well plate contained 500 μL of DMEM medium containing 10% FBS and 30 μM H2O2. PBS, AMOF, MnCO@AMOF, and T / MnCO@AMOF were added to different wells respectively. After culturing for 48 h, the cells were fixed with paraformaldehyde for 20 min, stained with crystal violet for 20 min, and the non-migrated cells inside the inner layer of the Transwell chamber were removed with a cotton swab. Finally, the cells in each well were observed and photographed under a microscope. The results are as Figure 21 shown, which can further demonstrate that MnCO@AMOF and T / MnCO@AMOF have the effect of promoting cell migration.

[0093] Angiogenesis-promoting property: Matrigel was added to a 96-well plate and placed in an incubator at 37 °C for 30 min to solidify. Then, 2×10 4 HUVECs were added onto the solidified Matrigel in each well, cultured with DMEM medium without FBS, and 30 μM H2O2 was added. PBS, AMOF, MnCO@AMOF, and T / MnCO@AMOF were added to different wells respectively. After culturing for 4 h, the cells were stained with 500 μM calcein for 30 min, and then photographed and recorded with an inverted fluorescence microscope. The results are as Figure 22 shown, which can demonstrate that MnCO@AMOF and T / MnCO@AMOF have the effect of promoting angiogenesis.

[0094] Example 8. Application of a multifunctional aggregation-induced emission metal-organic framework nanoparticle bilayer hydrogel microneedle patch in the treatment of infectious diabetic wounds

[0095] A diabetic model was established using C57 mice. The full-thickness skin on the back of the mice was excised to form a circular full-thickness wound with a diameter of 6 mm, and MRSA was dropped onto the wound to construct a bacterial infectious diabetic wound model. The wounds were treated with PBS, blank microneedle patches (MN), MnCO@AMOF microneedle patches, and T / MnCO@AMOF microneedle patches combined with 633 nm laser irradiation respectively.

[0096] On the 3rd day, bacteria were collected from the wound with PBS, diluted and inoculated onto LB solid medium, and the growth status of the bacteria was observed after overnight incubation. The results are as Figure 23As shown in Figure A. The number of bacteria in the T / MnCO@AMOF microneedle patch group was significantly reduced compared with other groups, indicating that the T / MnCO@AMOF microneedle patch has a bactericidal effect under light irradiation.

[0097] The wound healing conditions of the mice were photographed and recorded on the 0th, 3rd, 5th, 7th, 9th, 11th, and 14th days respectively. The results are as Figure 23 shown in Figure B, which shows that both the MnCO@AMOF microneedle patch group and the T / MnCO@AMOF microneedle patch group have the effect of promoting the healing of infected diabetic wounds compared with other groups, and the T / MnCO@AMOF microneedle patch group has a more significant healing-promoting effect.

[0098] The wound skin tissues on the 14th day were taken for Masson staining and H&E staining. The results are as Figure 23 shown in Figure C. The width of the granulation tissue gap in the T / MnCO@AMOF microneedle patch group was the smallest, and the collagen was more abundant. The skin healing condition of this group was the best.

[0099] The preparation process of the aggregation-induced emission metal-organic framework nanoparticle double-layer hydrogel microneedle patch for accelerating diabetic wound healing and the principle of accelerating diabetic wound healing involved in the above-mentioned embodiments are as Figure 24 shown.

[0100] The advantages of the present invention include: The metal-organic framework synthesized from tetrakis(4-carboxybiphenyl)ethylene (TCBE) and zinc acetate has fluorescence properties and can enhance the biocompatibility of drugs. TTI-COOH and dimanganese decacarbonyl inside the metal-organic framework have multiple biological functions such as antibacterial, anti-inflammatory, antioxidant, promoting cell migration, and promoting angiogenesis. Its antibacterial effect mainly depends on the photodynamic properties of TTI-COOH. The anti-inflammatory, antioxidant, promoting cell migration, and promoting angiogenesis effects mainly depend on the carbon monoxide generated by the Fenton-like reaction of dimanganese decacarbonyl with the high-level hydrogen peroxide in the diabetic wound microenvironment. The double-layer hydrogel microneedle patch enhances the tissue permeability of the nanoparticle drug and improves the drug efficacy. In addition, the double-layer hydrogel microneedle patch has good moisture absorption performance and can effectively remove the tissue exudate from the wound. The present invention is ingeniously designed and has a simple composition, and can effectively regulate multiple aspects of the diabetic wound healing process, ultimately promoting the healing of diabetic wounds.

[0101] The technical solutions provided by the embodiments of the present invention have been introduced in detail above. Specific examples are used in this article to elaborate on the principles and implementation manners of the embodiments of the present invention. The descriptions of the above embodiments are only applicable to help understand the principles of the embodiments of the present invention; at the same time, for those of ordinary skill in the art, according to the embodiments of the present invention, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. An AIE photosensitizer, characterized in that, Named TTI-COOH, with the structure shown in formula (Ⅰ):

2. A preparation method of the AIE photosensitizer according to claim 1, characterized in that the process includes: under the protection of an inert gas, dissolving 5-(4-(diphenylamino)phenyl)thiophene-2-carbaldehyde and 1-(2-carboxyethyl)-2,3,3-trimethyl-3H-indolium-1-bromide in a solvent, adding piperidine, stirring overnight at 70 °C, concentrating to obtain a crude product, and purifying and eluting to obtain a purple powdery product, which is TTI-COOH.

3. The preparation method of an AIE photosensitizer according to claim 2, characterized in that the process includes: under the protection of nitrogen, dissolving 355 mg of 5-(4-(diphenylamino)phenyl)thiophene-2-carbaldehyde and 249 mg of 1-(2-carboxyethyl)-2,3,3-trimethyl-3H-indolium-1-bromide in a mixed solvent of 15 mL of chloroform and 15 mL of ethanol, adding a drop of piperidine, stirring overnight at 70 °C, concentrating under reduced pressure to obtain a crude product, purifying and eluting to obtain a purple powdery product, which is TTI-COOH.

4. An aggregation-induced emission metal-organic framework nanoparticle for accelerating diabetic wound healing by applying the AIE photosensitizer according to claim 1, characterized in that it includes an aggregation-induced emission metal-organic framework composed of an aggregation-induced emission compound and metal zinc ions, a carbon monoxide releasing precursor and the AIE photosensitizer TTI-COOH loaded inside the aggregation-induced emission metal-organic framework, and an amphiphilic polymer wrapped outside the aggregation-induced emission metal-organic framework.

5. A preparation method of the aggregation-induced emission metal-organic framework nanoparticle for accelerating diabetic wound healing according to claim 4, characterized in that the steps include: heating and stirring an aggregation-induced emission compound and a zinc salt as raw materials to synthesize an aggregation-induced emission metal-organic framework; mixing and stirring the aggregation-induced emission metal-organic framework and a carbon monoxide releasing precursor, then mixing and stirring with the AIE photosensitizer, and finally dropping into an amphiphilic polymer solution and mixing and stirring to obtain the target product.

6. The preparation method of an aggregation-induced emission metal-organic framework nanoparticle for accelerating diabetic wound healing according to claim 5, characterized in that the steps include weighing 0.05 g of tetrakis(4-carboxybiphenyl)ethylene and dissolving it in 30 mL of DMF, weighing 0.54 g of zinc acetate and dissolving it in 30 mL of pure water, adding them together into a reaction vessel, stirring and refluxing at 120 °C for 10 min, adding 2 mL of 10 M KOH to adjust the pH of the reaction system to above 9, maintaining an alkaline atmosphere and continuing to heat and reflux for 6 h, cooling to room temperature after the reaction, centrifuging at 8000 rpm for 3 min, removing the supernatant, and resuspending the precipitate with pure water to obtain an aggregation-induced emission metal-organic framework suspension; Take 2 mL of the aggregation-induced emission metal-organic framework suspension and centrifuge it at 8000 rpm for 3 min. Discard the supernatant, add 1 mL of H2O and 1 mL of DMF, mix well, transfer it to a glass bottle, add 0.008 g of MnCO dissolved ultrasonically in 200 μL of DMF, and stir at room temperature overnight; then centrifuge the solution at 8000 rpm for 3 min, resuspend the precipitate in 2 mL of pure water, place it in a 500 Da dialysis bag, and dialyze for more than 12 h to obtain an aggregation-induced emission metal-organic framework suspension loaded with dimanganese decacarbonyl; Dissolve 2 mg of TTI-COOH in 1 mL of DMSO to prepare a 3.09 mM TTI-COOH solution, and then dilute it with pure water to a 2 mM TTI-COOH solution; centrifuge 1 mL of the aggregation-induced emission metal-organic framework suspension loaded with dimanganese decacarbonyl at 8000 rpm for 3 min, discard the supernatant, resuspend the precipitate in 1 mL of a 2 mM TTI-COOH solution, and stir overnight; then centrifuge at 8000 rpm for 3 min, dissolve the precipitate in 1 mL of pure water, and dialyze it using an 800 Da dialysis bag to obtain an aggregation-induced emission metal-organic framework suspension loaded with both dimanganese decacarbonyl and TTI-COOH; Dissolve BSA powder in ultrapure water to prepare a 5 mg / mL BSA solution. Take 1 mL of the aggregation-induced emission metal-organic framework suspension loaded with both dimanganese decacarbonyl and TTI-COOH, centrifuge it at 8000 rpm for 3 min, then discard the supernatant, and resuspend the precipitate in 1 mL of DMSO to make it evenly dispersed; place 9 mL of the BSA solution in a container, and while stirring at a high speed of 1000 rpm, add dropwise the aggregation-induced emission metal-organic framework loaded with dimanganese decacarbonyl and TTI-COOH after being resuspended in DMSO, and stir overnight to obtain the aggregation-induced emission metal-organic framework nanoparticles for accelerating diabetic wound healing.

7. Use of the aggregation-induced emission metal-organic framework nanoparticles for accelerating diabetic wound healing as described in claim 4 in the preparation of a drug for treating diabetic wounds.

8. A double-layer hydrogel microneedle patch using the aggregation-induced emission metal-organic framework nanoparticles for accelerating diabetic wound healing as described in claim 4, characterized in that: It includes a base layer and a needle body layer in contact with the wound. The needle bodies of the needle body layer are arranged in an array on the base layer. The base layer is formed by γ-PGA and ethylene glycol diglycidyl ether; the needle body layer is formed by loading the aggregation-induced emission metal-organic framework nanoparticles for accelerating diabetic wound healing with hyaluronic acid.

9. A preparation method of the double-layer hydrogel microneedle patch using the aggregation-induced emission metal-organic framework nanoparticles for accelerating diabetic wound healing as described in claim 8, characterized in that: The process includes: mixing an aqueous solution of the aggregation-induced emission metal-organic framework nanoparticles for accelerating diabetic wound healing with hyaluronic acid, filling the needle body part of a PDMS microneedle mold with the mixture after stirring evenly; mixing γ-PGA and ethylene glycol diglycidyl ether, adjusting the pH, and filling the solution into the base layer part of the PDMS microneedle mold; drying the mold at room temperature and then demolding to obtain a bilayer hydrogel microneedle patch of the aggregation-induced emission metal-organic framework nanoparticles for accelerating diabetic wound healing.

10. The preparation method of a bilayer hydrogel microneedle patch of the aggregation-induced emission metal-organic framework nanoparticles for accelerating diabetic wound healing according to claim 9, wherein: The detailed process includes: weighing 250 mg of hyaluronic acid, dissolving it with 1 mL of a suspension of the aggregation-induced emission metal-organic framework nanoparticles for accelerating diabetic wound healing with a concentration of 15 μg / mL, adding it to the PDMS microneedle mold, centrifuging at 3000 rpm for 3 min to remove air bubbles, rotating the centrifuge tube 180° and then centrifuging again to fully fill the needle body part with the liquid and remove the excess solution on the surface; then preparing a 12% wt γ-PGA and ethylene glycol diglycidyl ether aqueous solution, weighing 60 mg of γ-PGA, adding 420 μL of H2O, 21.45 μL of ethylene glycol diglycidyl ether, and 2 μL of concentrated hydrochloric acid to adjust the pH = 4, stirring and mixing evenly, and then spreading it on the surface of the PDMS microneedle mold, centrifuging at 3000 rpm for 3 min to remove air bubbles; finally, placing the filled mold in a closed drying container at room temperature for drying for 6 h and then demolding to obtain a bilayer hydrogel microneedle patch of the aggregation-induced emission metal-organic framework nanoparticles for accelerating diabetic wound healing.

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