A nanogel dressing, its preparation method and application

Abstract

This invention provides a nanogel dressing, its preparation method, and its application. The nanogel dressing comprises a hydrogel and a nanoparticle carrier loaded within the hydrogel; the nanoparticle carrier comprises a two-dimensional carbon material and gelatin coated on the surface of the two-dimensional carbon material. In this invention, the nanogel dressing is used to deliver wound-healing drugs, improving drug stability, prolonging the treatment time, exhibiting high drug loading capacity, and possessing good biocompatibility and mechanical properties, making it particularly suitable for treating chronic wounds such as those caused by diabetes.

Description

Technical Field

[0001] This invention belongs to the field of biomedical materials technology, specifically relating to a nanogel dressing, its preparation method, and its application. Background Technology

[0002] The skin, the largest organ in the human body, regulates body temperature, protects internal organs from external physical and chemical damage, and provides a physical barrier against pathogens and microorganisms. Normally, the skin has excellent regenerative capabilities and can heal rapidly after injury. However, some traumas causing severe skin damage, such as those caused by diabetes, exhibit abnormalities at the wound site, including delayed immune responses, impaired expression of various growth factors, abnormal angiogenesis, increased oxidative stress, and high expression of matrix metalloproteinases, hindering normal wound healing; in severe cases, this can even endanger the patient's life. Therefore, improving the treatment efficacy of chronic wounds caused by diabetes and other conditions, and promoting rapid wound healing, is of significant clinical importance.

[0003] Transforming growth factor (TGF) is a growth factor commonly used to promote wound healing. It can accelerate wound healing by promoting epidermal cell migration and angiogenesis, as well as by resisting oxidative stress. Although the application of TGF is relatively mature, it still has the following drawbacks: ① It has poor stability in vivo and is prone to degradation, resulting in low efficiency; ② Its effect is short-lived and it is difficult to maintain its effect in the long-term process of wound healing.

[0004] Therefore, developing a wound dressing that can improve the stability of wound healing drugs, prolong treatment time, has a high drug loading rate, and possesses good biocompatibility and mechanical properties is an urgent problem to be solved in this field. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a nanogel dressing, its preparation method, and its applications. The nanogel dressing is used to deliver therapeutic drugs, improving drug stability, prolonging treatment effects, accelerating wound healing, exhibiting high drug loading capacity, good antibacterial properties, and excellent biocompatibility and mechanical properties, making it particularly suitable for treating chronic wounds such as those caused by diabetes.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a nanogel dressing, the nanogel dressing comprising a hydrogel and a nanoparticle carrier loaded in the hydrogel; the nanoparticle carrier comprising a two-dimensional carbon material and gelatin coated on the surface of the two-dimensional carbon material.

[0008] In this invention, two-dimensional carbon materials exhibit good stability and antibacterial properties, as well as excellent dispersion. By coating the surface of the two-dimensional carbon materials with gelatin, the drug carrier can load the drug through charge self-assembly, enabling sustained release of the therapeutic drug on the wound surface. This not only improves drug stability and prevents drug inactivation but also prolongs treatment time and accelerates wound healing. Furthermore, loading the nanoparticle carrier into the hydrogel ensures the biocompatibility and mechanical properties of the dressing, while also providing some water absorption to keep the wound moist, making it particularly suitable for treating chronic wounds such as those caused by diabetes.

[0009] Preferably, the raw material of the hydrogel includes polyethylene glycol diacrylate.

[0010] Preferably, the number average molecular weight of the polyethylene glycol diacrylate is 5,000 to 10,000, for example, it can be 5,000, 5,500, 6,000, 6,500, 7,000, 7,500, 8,000, 8,500, 9,000, 9,500, 10,000, etc.

[0011] In this invention, the number-average molecular weight of the polyethylene glycol diacrylate is within the range defined above, resulting in a better hydrogel effect; if the molecular weight is too small, the hydrogel is prone to becoming brittle; if the molecular weight is too large, the cost is high and the performance is poor.

[0012] Preferably, the two-dimensional carbon material includes graphyne and / or graphene, and is more preferably graphyne.

[0013] Preferably, the mass of the two-dimensional carbon material is 10-20 mg (e.g., 10 mg, 11 mg, 12 mg, 13 mg, 14 mg, 15 mg, 16 mg, 17 mg, 18 mg, 19 mg, 20 mg, etc.), and the mass of the gelatin is 5-10 mg (e.g., 5 mg, 5.5 mg, 6 mg, 6.5 mg, 7 mg, 7.5 mg, 8 mg, 8.5 mg, 9 mg, 9.5 mg, 10 mg, etc.).

[0014] In this invention, if too much of the two-dimensional carbon material is used, the dispersion will be poor; if too little is used, the loading rate will be low.

[0015] Preferably, the mass ratio of the nanoparticle carrier to polyethylene glycol diacrylate is (0.5-1):(10-50), wherein the specific values ​​of (0.5-1) can be, for example, 0.5, 0.6, 0.7, 0.8, 0.9, 1, etc.; and the specific values ​​of (10-50) can be, for example, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, etc.

[0016] Preferably, the nanoparticle carrier surface is loaded with a drug.

[0017] Preferably, the drug is adsorbed onto the surface of the gelatin through electrostatic interaction.

[0018] Preferably, the drug comprises transforming growth factor.

[0019] In this invention, the nanogel dressing can also deliver other drugs, but it is particularly suitable for the delivery of transforming factors. This is because transforming factors have poor stability in vivo and are prone to degradation, resulting in low efficacy. Furthermore, their effects are short-lived and difficult to sustain during the long-term process of wound healing. The nanogel wound dressing provided by this invention can solve the problems of poor stability and short-lived effects of growth factors in current clinical applications. The released transforming factors can accelerate wound healing through anti-oxidation, promoting epidermal cell migration, and promoting angiogenesis.

[0020] In a second aspect, the present invention provides a method for preparing the nanogel dressing according to the first aspect, the preparation method comprising the following steps:

[0021] (1) Two-dimensional carbon materials are mixed with gelatin to obtain nanoparticle carriers;

[0022] (2) The nanoparticle carrier obtained in step (1) is mixed with hydrogel raw material and crosslinked to obtain the nanogel wound dressing.

[0023] Preferably, the two-dimensional carbon material in step (1) exists in the form of a two-dimensional carbon material dispersion.

[0024] Preferably, the preparation method of the two-dimensional carbon material dispersion includes: mixing the ground two-dimensional carbon material with a solvent and ultrasonically dispersing it to obtain the two-dimensional carbon material dispersion.

[0025] Preferably, the grinding time is 30 to 60 minutes, for example, 30 minutes, 35 minutes, 40 minutes, 45 minutes, 50 minutes, 55 minutes, 60 minutes, etc.

[0026] Preferably, the grinding method includes grinding 10 to 20 times per minute in a clockwise or counterclockwise direction, for example, 10, 12, 14, 16, 18, or 20 times per minute.

[0027] In this invention, an agate mortar and pestle are used for grinding until the two-dimensional carbon material is clearly transformed into a fine powder.

[0028] Preferably, the material mixed with the solvent also includes a dispersant.

[0029] In this invention, the dispersant includes, but is not limited to, sodium dodecyl sulfonate; the solvent of the two-dimensional carbon material dispersion includes water.

[0030] Preferably, the mass of the dispersant is 5-10 mg, based on the mass of the two-dimensional carbon material being 10-20 mg, for example, 5 mg, 6 mg, 7 mg, 8 mg, 9 mg, 10 mg, etc.; the volume of the solvent is 2-4 mL, for example, 2 mL, 2.5 mL, 3 mL, 3.5 mL, 4 mL, etc.

[0031] Preferably, the ultrasonic dispersion temperature is 0–8°C, for example, 0°C, 1°C, 2°C, 3°C, 4°C, 5°C, 6°C, 7°C, 8°C, etc.; the ultrasonic dispersion time is 90–120 min, for example, 90, 95, 100, 105, 110, 115, 120 min, etc.; the ultrasonic dispersion frequency is 30–40 kHz, for example, 30 kHz, 32 kHz, 34 kHz, 36 kHz, 38 kHz, 40 kHz, etc.; and the ultrasonic dispersion power is 400–500 W, for example, 400 W, 420 W, 440 W, 460 W, 480 W, 500 W, etc.

[0032] Preferably, the mixing temperature in step (1) is 37 to 45°C, for example, 37°C, 38°C, 40°C, 42°C, 44°C, 45°C, etc.

[0033] In this invention, a two-dimensional carbon material dispersion is mixed with gelatin at 37–45°C until the gelatin dissolves.

[0034] Preferably, the mixing step (1) further includes vortexing and centrifugation steps.

[0035] Preferably, the vortexing time is 1 to 2 minutes, for example, 1 minute, 1.2 minutes, 1.4 minutes, 1.6 minutes, 1.8 minutes, 2 minutes, etc.; the centrifugation time is 10 to 15 minutes, for example, 10 minutes, 11 minutes, 12 minutes, 13 minutes, 14 minutes, 15 minutes, etc.

[0036] In this invention, a two-dimensional carbon material dispersion is mixed with gelatin at 37–45°C until the gelatin dissolves. Then, the mixture is vortexed and centrifuged, the supernatant is discarded, and deionized water is added. The vortexing and centrifugation are repeated 2–3 times, and the supernatant is discarded to obtain a nanoparticle carrier precipitate.

[0037] Preferably, step (2) before mixing the nanoparticle carrier with the hydrogel raw material further includes a step of loading the drug onto the nanoparticle carrier.

[0038] Preferably, the specific method for loading drugs using nanoparticle carriers includes: mixing nanoparticle carriers with solvents to obtain nanoparticle carrier dispersions; then, mixing the nanoparticle carrier dispersions with drugs and incubating them, followed by vortexing and centrifugation to obtain drug-loaded nanoparticles.

[0039] Preferably, the mass percentage of nanoparticle carrier in the nanoparticle carrier dispersion is 0.5% to 1%, for example, it can be 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, etc.

[0040] In this invention, the concentration of the drug in the system is 100-200 μg / L, for example, it can be 100 μg / L, 120 μg / L, 140 μg / L, 160 μg / L, 180 μg / L, 200 μg / L, etc.

[0041] Preferably, the incubation time is 1 to 2 hours, for example, 1 hour, 1.2 hours, 1.4 hours, 1.6 hours, 1.8 hours, 2 hours, etc.; the incubation temperature is 35 to 45 degrees Celsius, for example, 35 degrees Celsius, 36 degrees Celsius, 38 degrees Celsius, 40 degrees Celsius, 42 degrees Celsius, 44 degrees Celsius, 45 degrees Celsius, etc.

[0042] Preferably, the vortexing time for obtaining the drug-loaded nanoparticles is 1 to 2 minutes, for example, 1 minute, 1.2 minutes, 1.4 minutes, 1.6 minutes, 1.8 minutes, 2 minutes, etc.; the centrifugation time is 10 to 15 minutes, for example, 10 minutes, 11 minutes, 12 minutes, 13 minutes, 14 minutes, 15 minutes, etc.

[0043] In this invention, the vortex and centrifugation are repeated 2 to 3 times.

[0044] Preferably, the mixed materials in step (2) further include an initiator.

[0045] In this invention, the initiator includes, but is not limited to, lithium phenyl (2,4,6-trimethylbenzoyl) phosphate; based on the mass concentration of polyethylene glycol diacrylate in the system being 5-10%, the amount of the initiator is 5-10 mg, for example, 5 mg, 6 mg, 7 mg, 8 mg, 9 mg, 10 mg, etc.

[0046] Preferably, the crosslinking is carried out under light irradiation.

[0047] In this invention, the illumination conditions include crosslinking under blue light irradiation.

[0048] In this invention, the power of the blue light is 600–900 mW / cm². 2 For example, it can be 600mW / cm 2 650mW / cm2 700mW / cm 2 750mW / cm 2 800mW / cm 2 850mW / cm 2 900mW / cm 2 wait.

[0049] Preferably, the illumination time is 10 to 30 seconds, for example, 10 seconds, 15 seconds, 20 seconds, 25 seconds, 30 seconds, etc.

[0050] Preferably, the wavelength of the illumination is 400-410nm, for example, it can be 400nm, 402nm, 404nm, 406nm, 408nm, 410nm, etc.

[0051] In this invention, the centrifugation speed is 15,000 to 20,000 rpm, for example, it can be 15,000 rpm, 16,000 rpm, 17,000 rpm, 18,000 rpm, 19,000 rpm, 20,000 rpm, etc.

[0052] In this invention, when the nanogel dressing is used in in vivo experiments, a sterilization step is also included; specifically, the gel is soaked in alcohol for 24 to 48 hours, and then soaked in deionized water for 8 to 16 hours until the alcohol solvent is completely removed.

[0053] The preparation method provided by this invention is simple and easy to operate, and does not involve complex reaction processes or expensive instruments.

[0054] The gel in this invention is a photosensitive hydrogel, which can be used as an ink material for 3D printing and for subsequent personalized wound dressings.

[0055] Thirdly, the present invention provides the application of the nanogel dressing as described in the first aspect in drug delivery.

[0056] The numerical range described in this invention includes not only the point values ​​listed above, but also any point values ​​within the numerical ranges not listed above. Due to space limitations and for the sake of brevity, this invention will not exhaustively list all the specific point values ​​included in the range.

[0057] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0058] The nanogel dressing provided by this invention uses gelatin-modified two-dimensional carbon nanoparticles as drug carriers. Drugs are loaded via charge self-assembly, ensuring a safe and non-toxic loading process that does not lead to drug inactivation or degradation, thus improving drug stability and loading rate. Simultaneously, it provides sustained drug release, prolonging the drug's effect and accelerating wound healing. Furthermore, by encapsulating the drug-loaded nanoparticle carrier within a hydrogel, the dressing's biocompatibility and mechanical properties are enhanced, maintaining wound moisture and making it particularly suitable for delivering wound-healing-promoting drugs. Attached Figure Description

[0059] Figure 1 Macroscopic and microscopic views of the nanogel dressing provided in Example 1 and the ordinary gel dressing provided in Comparative Example 1;

[0060] in, Figure 1 Image a shows a general view of a typical gel dressing. Figure 1 b is a microstructure diagram of a common gel dressing; Figure 1 c is a general view of the nanogel dressing. Figure 1 d is a microstructure diagram of the nanogel dressing;

[0061] Figure 2 Transmission electron microscopy image of drug sustained release from nanogel dressing under infrared irradiation;

[0062] in, Figure 2 Image a is a transmission electron microscope image of the nanogel dressing before infrared irradiation. Figure 2 b is a transmission electron microscope image of the nanogel dressing after 60 seconds of infrared irradiation. Figure 2 c is a transmission electron microscope image of the nanogel dressing after 360s of infrared irradiation.

[0063] Figure 3 The mechanical property test results are for the nanogel dressing provided in Example 1 and the ordinary gel dressing provided in Comparative Example 1.

[0064] in, Figure 3 A represents the test results of compressive mechanical properties; Figure 3 B represents the tensile mechanical property test results; Figure 3 C represents the fluid dynamics performance test results;

[0065] Figure 4 The results of cell biocompatibility tests for the nanogel dressing provided in Example 1 and the ordinary gel dressing provided in Comparative Example 1;

[0066] in, Figure 4 a represents the survival rate of fibroblasts after 7 days of culture using ordinary gel dressing; Figure 4 b shows the survival rate of fibroblasts after 7 days of culture using nanogel dressing;

[0067] Figure 5 The test results show the antibacterial properties of the nanogel dressing provided in Example 1 and the ordinary gel dressing provided in Comparative Example 1.

[0068] in, Figure 5 a represents the bacterial content in the culture dish before infrared irradiation using ordinary gel dressing; Figure 5 c represents the bacterial content in the culture dish after infrared irradiation using ordinary gel dressing; Figure 5 b represents the bacterial content in the culture dish before infrared irradiation using nanogel dressing; Figure 5 d represents the bacterial content in the culture dish after infrared irradiation using nanogel dressing;

[0069] Figure 6A and Figure 6B The results of promoting wound healing by the nanogel dressing provided in Example 1 and the ordinary gel dressing provided in Comparative Example 1;

[0070] in, Figure 6A The wound healing status of mice at different time points; Figure 6B Figure 1 shows the results of wound healing rates in mice at different time points.

[0071] Figure 7 The results of the nanogel dressing provided in Example 4 promoting wound healing;

[0072] in, Figure 7 A represents the wound healing status of mice at different time points; Figure 7 Figure B shows the results of the wound healing rate of mice at different times using the nanogel dressings provided in Examples 1 and 4. Detailed Implementation

[0073] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0074] Example 1

[0075] This embodiment provides a nanogel dressing, comprising a polyethylene glycol diacrylate hydrogel and a nanoparticle carrier loaded in the hydrogel; the nanoparticle carrier comprises graphyne and gelatin coated on the surface of the graphyne; the surface of the gelatin is loaded with transforming growth factor through electrostatic interaction.

[0076] This embodiment provides a method for preparing a nanogel dressing, specifically including the following steps:

[0077] (1) Weigh 15mg of graphyne powder and grind it in an agate mortar. Grind 15 times per minute in a clockwise direction along the mortar for a total of 40min until the graphyne powder becomes significantly finer. Mix the ground graphyne with 3mL of deionized water and add 5mg of sodium dodecyl sulfonate (SDS) powder. Place it in an ultrasonic disperser and disperse it for 100min at a frequency of 40kHz, a power of 400W and a temperature of 4℃ to obtain a graphyne dispersion.

[0078] (2) Add 10 mg of gelatin particles to the graphyne dispersion obtained in step (1), heat to 40°C until the gelatin particles are completely dissolved, vortex for 2 min, centrifuge at 18000 rpm for 15 min, discard the supernatant, add deionized water and vortex again for 2 min, centrifuge at 18000 rpm for 15 min and discard the supernatant. Repeat this washing method twice to obtain the graphyne nanoparticle carrier precipitate.

[0079] (3) Add an appropriate amount of deionized water to the graphyne nanoparticle carrier precipitate obtained in step (2) to prepare a 0.8% graphyne nanoparticle carrier dispersion. Add 10 ng of transforming growth factor TGF-β to it and adjust the TGF-β concentration to 100 μg / L. After incubating in a constant temperature oven at 37℃ for 2 h, add deionized water and vortex for 2 min. After centrifuging at 18000 rpm for 10 min, discard the supernatant. Repeat this process twice to obtain nanoparticles loaded with TGF-β.

[0080] (4) The nanoparticles obtained in step (3) are mixed with polyethylene glycol diacrylate (PEGDA) powder with a molecular weight of 10k and deionized water to prepare an 8% PEGDA solution. 8 mg of lithium phenyl (2,4,6-trimethylbenzoyl) phosphate (LAP) powder is added until completely dissolved. 100 μL of the resulting solution is placed in a mold and heated with a power of 700 mW / cm². 2 The nanogel dressing was obtained by irradiating the dressing with blue light (wavelength 405nm) for 20s; the obtained gel was carefully peeled off and demolded, and stored in a sealed container.

[0081] In this invention, if in vivo experiments are required, the nanogel dressing is soaked in alcohol for 36 hours, then soaked in deionized water for 12 hours until the alcohol solvent is completely removed, and finally sealed in a sterile container for storage.

[0082] Example 2

[0083] This embodiment provides a nanogel dressing, comprising a polyethylene glycol diacrylate hydrogel and a nanoparticle carrier loaded in the hydrogel; the nanoparticle carrier comprises graphyne and gelatin coated on the surface of the graphyne; the surface of the gelatin is loaded with transforming growth factor through electrostatic interaction.

[0084] This embodiment provides a method for preparing a nanogel dressing, specifically including the following steps:

[0085] (1) Weigh 18mg of graphyne powder and grind it in an agate mortar. Grind 20 times per minute in a clockwise direction along the mortar for a total of 50min until the graphyne powder becomes significantly finer. Mix the ground graphyne with 4mL of deionized water and add 9mg of sodium dodecyl sulfonate (SDS) powder. Place it in an ultrasonic disperser and disperse it for 100min at a frequency of 40kHz, a power of 500W and a temperature of 4℃ to obtain a graphyne dispersion.

[0086] (2) Add 10 mg of gelatin particles to the graphyne dispersion obtained in step (1), heat to 40°C until the gelatin particles are completely dissolved, vortex for 2 min, centrifuge at 18000 rpm for 15 min, discard the supernatant, add deionized water and vortex again for 2 min, centrifuge at 18000 rpm for 15 min and discard the supernatant. Repeat this washing method twice to obtain the graphyne nanoparticle carrier precipitate.

[0087] (3) Add an appropriate amount of deionized water to the graphyne nanoparticle carrier precipitate obtained in step (2) to prepare a 1% graphyne nanoparticle carrier dispersion. Add transforming growth factor TGF-β to it so that the TGF-β concentration is 200 μg / L. After incubating in a constant temperature oven at 37℃ for 2 h, add deionized water and vortex for 2 min. After centrifuging at 18000 rpm for 10 min, discard the supernatant. Repeat this process twice to obtain nanoparticles loaded with TGF-β.

[0088] (4) The nanoparticles obtained in step (3) are mixed with polyethylene glycol diacrylate (PEGDA) powder with a number average molecular weight of 8k and deionized water to prepare a 10% PEGDA solution. 10 mg of lithium phenyl (2,4,6-trimethylbenzoyl) phosphate (LAP) powder is added until completely dissolved. 100 μL of the resulting solution is placed in a mold and heated with a power of 700 mW / cm². 2 The nanogel dressing was obtained by irradiating the dressing with blue light (wavelength 405nm) for 20s; the obtained gel was carefully peeled off and demolded, and stored in a sealed container.

[0089] In this invention, if in vivo experiments are required, the nanogel dressing is soaked in alcohol for 36 hours, then soaked in deionized water for 12 hours until the alcohol solvent is completely removed, and finally sealed in a sterile container for storage.

[0090] Example 3

[0091] This embodiment provides a nanogel dressing, comprising a polyethylene glycol diacrylate hydrogel and a nanoparticle carrier loaded in the hydrogel; the nanoparticle carrier comprises graphyne and gelatin coated on the surface of the graphyne; the surface of the gelatin is loaded with transforming growth factor through electrostatic interaction.

[0092] This embodiment provides a method for preparing a nanogel dressing, specifically including the following steps:

[0093] (1) Weigh 12mg of graphyne powder and grind it in an agate mortar. Grind 10 times per minute in a clockwise direction along the mortar for a total of 30min until the graphyne powder becomes significantly finer. Mix the ground graphyne with 2mL of deionized water and add 6mg of sodium dodecyl sulfonate (SDS) powder. Place it in an ultrasonic disperser and disperse it for 100min at a frequency of 40kHz, a power of 500W and a temperature of 4℃ to obtain a graphyne dispersion.

[0094] (2) Add 6 mg of gelatin particles to the graphyne dispersion obtained in step (1), heat to 40°C until the gelatin particles are completely dissolved, vortex for 2 min, centrifuge at 18000 rpm for 15 min, discard the supernatant, add deionized water and vortex again for 2 min, centrifuge at 18000 rpm for 15 min and discard the supernatant. Repeat this washing method twice to obtain the graphyne nanoparticle carrier precipitate.

[0095] (3) Add an appropriate amount of deionized water to the graphyne nanoparticle carrier precipitate obtained in step (2) to prepare a 0.5% graphyne nanoparticle carrier dispersion. Add transforming growth factor TGF-β to it so that the TGF-β concentration is 200 μg / L. After incubating in a constant temperature oven at 37℃ for 2 h, add deionized water and vortex for 2 min. After centrifuging at 18000 rpm for 10 min, discard the supernatant. Repeat this process twice to obtain nanoparticles loaded with TGF-β.

[0096] (4) The drug-loaded nanoparticles obtained in step (3) are mixed with polyethylene glycol diacrylate (PEGDA) powder with a number average molecular weight of 10k and deionized water to prepare a 6% PEGDA solution. 5 mg of lithium phenyl (2,4,6-trimethylbenzoyl) phosphate (LAP) powder is added until completely dissolved. 100 μL of the resulting solution is placed in a mold and heated with a power of 700 mW / cm². 2 The nanogel dressing was obtained by irradiating the dressing with blue light (wavelength 405nm) for 20s; the obtained gel was carefully peeled off and demolded, and stored in a sealed container.

[0097] In this invention, if in vivo experiments are required, the nanogel dressing is soaked in alcohol for 36 hours, then soaked in deionized water for 12 hours until the alcohol solvent is completely removed, and finally sealed in a sterile container for storage.

[0098] Example 4

[0099] This embodiment provides a nanogel dressing, which differs from Embodiment 1 only in that the graphyne is replaced with an equal amount of graphene, while the other raw materials, dosages and preparation methods are the same as in Embodiment 1.

[0100] Comparative Example 1

[0101] This comparative example provides a common gel dressing, which differs from Example 1 only in that the gel dressing does not contain graphylene, while the other raw materials, dosages, and preparation processes are the same as in Example 1.

[0102] Test Example 1

[0103] The macroscopic images of the nanogel dressing provided in Example 1 and the ordinary gel dressing provided in Comparative Example 1 were observed visually, and the microstructures of the nanogel dressing provided in Example 1 and the ordinary gel dressing provided in Comparative Example 1 were characterized using scanning electron microscopy. The results are as follows: Figure 1 As shown, where, Figure 1 Image a shows a general view of a typical gel dressing. Figure 1 b is a microstructure diagram of a common gel dressing; Figure 1 c is a general view of the nanogel dressing. Figure 1 d shows the microstructure of the nanogel dressing; from the macroscopic image, it can be seen that the gel dressing incorporating graphite nanoparticles is black, and the surface of the microstructure exhibits a porous morphology. Its pore size is larger than that of ordinary gel dressings, which is more conducive to cell ingrowth and tissue regeneration. At the same time, it is conducive to the vascularization of tissue engineering materials and can provide a suitable environment for wound healing.

[0104] Test Example 2

[0105] The nanogel dressing described in Example 1 was subjected to sustained drug release under infrared irradiation, and the results were observed under a transmission electron microscope; the results are as follows. Figure 2 As shown, where, Figure 2 Image a is a transmission electron microscope image of the nanogel dressing before infrared irradiation. Figure 2 b is a transmission electron microscope image of the nanogel dressing after 60 seconds of infrared irradiation. Figure 2 c shows a transmission electron microscope (TEM) image of the nanogel dressing after 360 seconds of infrared irradiation. The TEM image reveals that before infrared irradiation, the nanoparticles exhibit a multilayered structure. With the photothermal effect under infrared irradiation, the outer layer of the multilayered structure gradually decomposes, releasing transforming growth factor (TGF) into the body. After a period of infrared irradiation, all the outer layer decomposes, the drug is completely released, and only the core nanoparticles remain visible. This demonstrates that the nanogel dressing can continuously deliver TGF under infrared irradiation.

[0106] Test Example 3

[0107] The nanogel dressing provided in Example 1 and the ordinary gel dressing provided in Comparative Example 1 were subjected to tensile mechanical tests. Figure 3 B) Compression mechanics Figure 3 A) and fluid mechanics Figure 3 C) Performance testing; the specific process includes: cutting the gel into strips 30mm long, 10mm wide, and 2mm thick, clamping both sides with a universal instrument, and cyclically stretching at a constant speed of 2mm / min until the gel completely breaks, recording the corresponding tensile strain and tensile stress; cutting the gel into cylindrical bodies 5mm high and 10mm in diameter, placing them on the platform of the universal instrument, and cyclically compressing them to 50% at a constant speed of 1mm / min, recording the corresponding compressive strain and compressive stress; placing small gel discs 2mm high and 10mm in diameter on a rheometer, with a constant shear frequency of 10Hz, gradually increasing the shear strain to 1000%, and recording the modulus values ​​under different strain conditions.

[0108] pass Figure 3 The experimental results show that the elastic modulus of the nanogel dressing is significantly better than that of ordinary gel, and its tensile mechanical properties, compressive mechanical properties and fluid shear mechanical properties are significantly improved.

[0109] Test Example 4

[0110] The cell biocompatibility of the nanogel dressing provided in Example 1 was tested. The gel was prepared into small discs with a height of 2 mm and a diameter of 10 mm, sterilized, and stored in a sterile container. Human skin fibroblasts were cultured and expanded, and a concentration of 10 was collected and prepared. 6A fibroblast suspension of cells / mL was dropped onto the surface of a gel slide and incubated in a cell culture incubator for 2 hours. After 7 days of culture in complete culture medium, live and dead cells were stained and observed under a confocal microscope. The stained cell images are shown below. Figure 4 As shown; where, Figure 4 a represents the survival rate of fibroblasts after 7 days of culture using ordinary gel dressing; Figure 4 b represents the survival rate of fibroblasts after 7 days of culture using nanogel dressing.

[0111] Experimental results demonstrate that the nanogel dressing has good cell biocompatibility, and fibroblasts can proliferate well inside the gel.

[0112] Test Example 5

[0113] The antibacterial effects of the nanogel dressing provided in Example 1 and the ordinary gel provided in Comparative Example 1 were tested. Staphylococcus aureus, the most common Gram-positive bacterium in skin infections, was selected, amplified, and collected at a concentration of 10... 7 A bacterial suspension of [number] cells / mL was prepared, and small gel discs were added. After 2 minutes of infrared light incubation, the bacterial suspension was spread onto agarose gel culture dishes. The bacterial amplification after treatment was compared, and the bacterial amplification images are shown below. Figure 5 As shown; where, Figure 5 a represents the bacterial content in the culture dish before infrared irradiation using ordinary gel dressing; Figure 5 c represents the bacterial content in the culture dish after infrared irradiation using ordinary gel dressing; Figure 5 b represents the bacterial content in the culture dish before infrared irradiation using nanogel dressing; Figure 5 d represents the bacterial content in the culture dish after infrared irradiation using nanogel dressing.

[0114] The comparison shows that the bacterial content of the nano-gel dressing is significantly reduced after infrared irradiation, almost to the point of being non-existent, indicating that the antibacterial effect of the nano-gel dressing provided by the present invention is significantly better than that of ordinary gel dressings. However, the difference is not significant under conditions without light irradiation.

[0115] Test Example 6

[0116] The nanogel dressing provided in Example 1 and the ordinary gel dressing provided in Comparative Example 1 were used to test wound healing. Six-week-old male C57 mice were selected for the experiment. A circular full-thickness skin wound with a diameter of 10 mm was prepared on the back. A silicone ring was used to fix the wound around the wound to prevent interference from skin contraction on the experimental results. The gel dressing was placed on the wound and photographed at different time points to observe the healing of the mouse skin surface. Figure 6A ), and calculate the healing rate ( Figure 6B ).

[0117] Experimental results demonstrate that the nanogel dressing provided by this invention is significantly better than ordinary gel dressings in promoting wound healing, achieving near-complete healing within 14 days.

[0118] Test Example 7

[0119] The nanogel dressing provided in Example 4 was used to test wound healing and compared with that in Example 1. Six-week-old male C57 mice were selected for the experiment. A circular full-thickness skin wound with a diameter of 10 mm was prepared on the back. A silicone ring was used to fix the wound around the wound to prevent interference from skin contraction on the experimental results. The gel dressing was placed on the wound and photographed at different time points to observe the healing of the mouse skin surface. Figure 7 A), and calculate the healing rate ( Figure 7 B).

[0120] Experimental results demonstrate that the optimal solution for the nanogel dressing provided by this invention, namely the graphdiyne nanogel dressing, is superior to the graphene nanogel dressing in promoting wound healing, but both are superior to ordinary gel dressings.

[0121] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A nanogel dressing, characterized in that, The nanogel dressing includes a hydrogel and a nanoparticle carrier loaded in the hydrogel. The nanoparticle carrier includes a two-dimensional carbon material and gelatin coated on the surface of the two-dimensional carbon material. The raw material of the hydrogel includes polyethylene glycol diacrylate; The number average molecular weight of the polyethylene glycol diacrylate is 5000~10000; The two-dimensional carbon material is graphynylene; The nanoparticle carrier surface is loaded with drugs; The drug is adsorbed onto the surface of the gelatin through electrostatic attraction; The drug includes transforming growth factor.

2. The nanogel dressing according to claim 1, characterized in that, With the mass of the two-dimensional carbon material being 10-20 mg, the mass of the gelatin is 5-10 mg.

3. The nanogel dressing according to claim 1, characterized in that, The mass ratio of the nanoparticle carrier to polyethylene glycol diacrylate is (0.5~1):(10~50).

4. A method for preparing a nanogel dressing according to any one of claims 1 to 3, characterized in that, The preparation method includes the following steps: (1) Two-dimensional carbon materials are mixed with gelatin to obtain nanoparticle carriers; (2) The nanoparticle carrier obtained in step (1) is mixed with the raw material of hydrogel and crosslinked to obtain the nanogel dressing.

5. The preparation method according to claim 4, characterized in that, The two-dimensional carbon material in step (1) exists in the form of a two-dimensional carbon material dispersion.

6. The preparation method according to claim 5, characterized in that, The preparation method of the two-dimensional carbon material dispersion includes: mixing the ground two-dimensional carbon material with a solvent, and ultrasonically dispersing it to obtain the two-dimensional carbon material dispersion.

7. The preparation method according to claim 6, characterized in that, The grinding time is 30-60 minutes.

8. The preparation method according to claim 6, characterized in that, The grinding method includes grinding 10 to 20 times per minute in a clockwise or counterclockwise direction.

9. The preparation method according to claim 6, characterized in that, The material mixed with the solvent also includes a dispersant.

10. The preparation method according to claim 9, characterized in that, With the mass of the two-dimensional carbon material being 10-20 mg, the mass of the dispersant being 5-10 mg, and the volume of the solvent being 2-4 mL.

11. The preparation method according to claim 6, characterized in that, The ultrasonic dispersion temperature is 0~8℃, the ultrasonic dispersion time is 90~120 min, the ultrasonic dispersion frequency is 30~40 kHz, and the ultrasonic dispersion power is 400~500W.

12. The preparation method according to claim 4, characterized in that, The mixing temperature in step (1) is 37~45℃.

13. The preparation method according to claim 4, characterized in that, Step (1) after mixing also includes vortexing and centrifugation.

14. The preparation method according to claim 13, characterized in that, The vortexing time is 1-2 min, and the centrifugation time is 10-15 min.

15. The preparation method according to claim 4, characterized in that, Step (2) Before mixing the raw materials of the nanoparticle carrier and the hydrogel, the step of loading the drug onto the nanoparticle carrier is also included.

16. The preparation method according to claim 15, characterized in that, The specific method for loading drugs using nanoparticle carriers includes: mixing nanoparticle carriers with solvents to obtain nanoparticle carrier dispersions; then, mixing the nanoparticle carrier dispersions with drugs and incubating them, followed by vortexing and centrifugation to obtain drug-loaded nanoparticles.

17. The preparation method according to claim 16, characterized in that, The mass percentage of nanoparticle carrier in the nanoparticle carrier dispersion is 0.5-1%.

18. The preparation method according to claim 16, characterized in that, The incubation time is 1-2 hours, and the incubation temperature is 35-45℃.

19. The preparation method according to claim 16, characterized in that, The vortexing time for obtaining the drug-loaded nanoparticles is 1-2 min, and the centrifugation time is 10-15 min.

20. The preparation method according to claim 4, characterized in that, The mixed materials in step (2) also include an initiator.

21. The preparation method according to claim 4, characterized in that, The crosslinking is carried out under light conditions.

22. The preparation method according to claim 21, characterized in that, The illumination time is 10~30 s.

23. The preparation method according to claim 21, characterized in that, The wavelength of the illumination is 400~410 nm.

24. The use of a nanogel dressing as described in any one of claims 1 to 3 in the preparation of a drug delivery product.

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