Hydrogel wound dressing as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of biomedical materials, and particularly relates to a hydrogel wound dressing and a preparation method and application thereof. The hydrogel wound dressing disclosed by the invention can be matched with a sound-sensitive agent by utilizing the temperature-sensitive shrinkage performance of the temperature-sensitive compound monomer, and shows ultrasonic thermal response shrinkage performance, specifically, the hydrogel wound dressing can be rapidly heated and remarkably shrunk under the ultrasonic action to promote wound shrinkage, so that wound healing is accelerated. The obvious potential is embodied in the aspects of promoting the repair of the wound infected by the drug-resistant bacteria and the repair of the wound infected by the drug-resistant bacteria and diabetes mellitus. When the prepared hydrogel wound dressing is used, the contraction degree of the hydrogel wound dressing can be controlled by adjusting the ultrasonic time in the treatment process, and protection and treatment effects on drug-resistant bacteria wounds are achieved in a programmed mode. Meanwhile, the fixing structure of the hydrogel can anchor added drugs such as a sound-sensitive agent and the like, and the action time of the drugs is prolonged.

Description

Technical Field

[0001] The present application belongs to the technical field of medical materials, and specifically relates to a hydrogel wound dressing and a preparation method and application thereof. Background Art

[0002] The problem of bacterial resistance is becoming increasingly serious, posing a huge challenge to the healing of chronic wounds. As a broad-spectrum, highly effective antibacterial agent, quaternary ammonium cations are based on the antibacterial principle of their cationic surfactant properties. They interact with the negative charge on the bacterial cell membrane through their positively charged molecular structure, destroying the integrity of the cell membrane, leading to abnormal exchange of substances inside and outside the cell, and ultimately causing the bacteria to lose activity or die. Quaternary ammonium salts can also penetrate the cell wall, bind to substances such as DNA and RNA in the cell, and interfere with the normal metabolism and reproduction of bacteria. Quaternary ammonium compounds provide a new direction for the development of antibacterial materials.

[0003] The Chinese patent with publication number CN118716339A discloses the application of a polymer-based antibacterial gel in eliminating bacterial biofilms. A cationic antibacterial polymer with a low positive charge density and a poloxamer gel are used in combination to have a synergistic effect in removing bacterial biofilms. The cationic antibacterial polymer with a low positive charge density is a polycarboxyl polymer modified with a quaternary ammonium salt or a polyamino polymer modified with a fluorinated alkyl chain. The combined use method is to mix the cationic antibacterial polymer with a low positive charge density and the poloxamer in the form of an aqueous solution. In the mixed solution, the concentration of the poloxamer is 200-300 mg / mL. A specific type of cationic antibacterial polymer within the synergistic concentration range can combine the effect of the poloxamer in dissipating biofilms with the killing effect of the antibacterial polymer on bacteria.

[0004] Nevertheless, for patients with diseases such as diabetes, the disease can cause vascular and nerve damage, making the patient's wound healing process abnormally slow. Due to the special physiological conditions, the above-mentioned patented gel has low therapeutic efficiency in treating complex wounds caused by chronic diseases. Therefore, the development of more effective antibacterial strategies remains an important direction for future research. Summary of the invention

[0005] In order to solve the above technical problems, the present application mainly provides a method for preparing a hydrogel wound dressing, which is specifically achieved through the following technical solutions:

[0006] A method for preparing a hydrogel wound dressing comprises the following steps:

[0007] S1, dispersing polyethylene glycol diacrylate, a temperature-sensitive compound monomer and a quaternary ammonium salt compound monomer in a solution, adding an initiator, and reacting to obtain a quaternary ammonium salt temperature-sensitive hyperbranched polymer;

[0008] S2, preparing a quaternary ammonium salt thermosensitive hyperbranched polymer aqueous solution, and dispersing the sonosensitizer therein to obtain a solution A;

[0009] S3. Using an aqueous solution of thiolated hyaluronic acid as solution B, mixing solution A with solution B, and allowing to stand to form a gel to obtain a hydrogel wound dressing.

[0010] The present application uses polyethylene glycol diacrylate as a main chain monomer, a thermosensitive compound monomer and a quaternary ammonium salt compound monomer as polymerization monomers, and synthesizes a quaternary ammonium salt thermosensitive hyperbranched polymer with a brush structure through reversible addition-fragmentation chain transfer and atom transfer free radical polymerization under the action of an initiator. Further, hyaluronic acid, which exists in large quantities in the body, is used as the main body, and the quaternary ammonium salt thermosensitive hyperbranched polymer is introduced to anchor the hyperbranched polymer and the thiol-Michael addition reaction of the hyperbranched polymer and the thiol-hyaluronic acid solution to obtain a hydrogel wound dressing.

[0011] Preferably, in step S1, the temperature-sensitive compound monomer is N-isopropylacrylamide; and the quaternary ammonium salt compound monomer is acryloyloxyethyltrimethylammonium chloride.

[0012] Preferably, in step S1, the solvent is dimethyl sulfoxide, and the initiator is azobisisobutyronitrile / disulfiram.

[0013] Preferably, in step S1, the mass fraction of the polyethylene glycol diacrylate is 10-40%, the mass fraction of the temperature-sensitive compound monomer is 10-40%, and the mass fraction of the quaternary ammonium salt compound monomer is 10-40%.

[0014] Preferably, in the solution A of step S2, the mass percentage concentration of the quaternary ammonium salt thermosensitive hyperbranched polymer is 5-50%; and the concentration of the sonosensitizer is 100-500 μg / mL.

[0015] Preferably, in the solution B of step S3, the mass percentage concentration of thiolated hyaluronic acid is 1-10%.

[0016] Preferably, in step S3, the mass ratio of the quaternary ammonium salt thermosensitive hyperbranched polymer to the thiolated hyaluronic acid is (1-10):(1-10).

[0017] Preferably, in step S3, the standing gelation conditions are: temperature 20-25° C., time 1-3 min.

[0018] A hydrogel wound dressing prepared by any of the above preparation methods.

[0019] Use of any of the above hydrogel wound dressings in the preparation of a drug for treating or preventing wounds infected with drug-resistant bacteria.

[0020] Compared with the prior art, this application has the following beneficial effects:

[0021] The hydrogel wound dressing of the present application utilizes the thermosensitive contraction performance of the thermosensitive compound monomer, and can be matched with the sonosensitizer to show ultrasonic thermal response contraction performance, which is specifically reflected in that it can quickly heat up and shrink significantly under the action of ultrasound to promote wound contraction, thereby accelerating wound healing. It shows significant potential in promoting wound repair.

[0022] During the use of the hydrogel wound dressing prepared in the present application, the contraction degree of the hydrogel wound dressing can be controlled by adjusting the ultrasonic time during the treatment process, so as to play a programmed protective and therapeutic role on the wound surface. At the same time, the fixed structure of the hydrogel can anchor the sonosensitizer and other added drugs to prolong their action time.

[0023] The ultrasonically responsive thermosensitive injectable antibacterial hydrogel wound dressing provided by the present application has a low modulus, still has a weak fluidity after gelation, and is injectable; and the main component includes hyaluronic acid naturally present in the body, and has little toxic side effects. The preparation method of the gel wound dressing is simple and fast, providing a new treatment approach for chronic infected wounds. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The schematic diagram of the thermosensitive contraction of the hydrogel wound dressing;

[0025] Figure 2 is the reaction formula of quaternary ammonium salt thermosensitive hyperbranched polymer;

[0026] Figure 3 The H NMR spectrum obtained from the performance test 1;

[0027] Figure 4 This is the infrared spectrum obtained from the performance test 1;

[0028] Figure 5 A diagram showing the gelling process of the hydrogel wound dressing of this application;

[0029] Figure 6 This is an electron microscopic image of the hydrogel wound dressing for performance test 1;

[0030] Figure 7 This is a test diagram of the storage modulus and loss modulus of the hydrogel wound dressing in performance test 1;

[0031] Figure 8 This is a test diagram of ultrasonic responsiveness of hydrogel wound dressing in performance test 1;

[0032] Fig. 9 and Fig.10 This is a diagram showing the antibacterial performance test results of the hydrogel wound dressing in performance test 2. DETAILED DESCRIPTION

[0033] The present application will be further described below in the form of specific embodiments. Those of ordinary skill in the art will be able to implement the present application based on these descriptions. In addition, the embodiments of the present application involved in the following description are generally only embodiments of a part of the present application, rather than all embodiments. Therefore, based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative work should fall within the scope of protection of the present application.

[0034] Example 1

[0035] This embodiment discloses a hydrogel wound dressing, and the preparation method of the hydrogel wound dressing is as follows:

[0036] S1. Mix the dimethyl sulfoxide solutions of polyethylene glycol diacrylate (PEGDA), N-isopropylacrylamide (NIPAm) and acryloyloxyethyltrimethylammonium chloride (ACB). Then, add azobisisobutyronitrile / disulfiram (AIBN / DS) dropwise into the mixed solution and transfer it to a Schlenk bottle. In this embodiment, the ratio of PEGDA:NIPAm:ACB:AIBN:DS is 25:50:50:1.4:1. Degas the solution in the Schlenk bottle by three freeze-thaw cycles, keep the reaction at 70°C for 7h, and stop the reaction by natural cooling. Dialyze with a dialysis bag for 3 days, freeze-dry the obtained dialysate, and obtain a white foam-like product, a quaternary ammonium salt thermosensitive hyperbranched polymer, which is stored in a -20°C refrigerator.

[0037] S2. Prepare a 20% by mass aqueous solution of a quaternary ammonium salt thermosensitive hyperbranched polymer (QTHP), and mix it with an equal volume concentration of 400 μg / mL of a carnosine-zinc ultrasound-responsive piezoelectric MOF (PMOF) dispersion synthesized by a hydrothermal method as solution A.

[0038] S3. Prepare an aqueous solution of thiolated hyaluronic acid, wherein the mass percentage concentration of thiolated hyaluronic acid is 2%, as solution B.

[0039] S4. Add solution B to solution A, mix them evenly with equal volumes, adjust the pH of the solution to 8.5, and let it stand at room temperature for 2 minutes to form a gel, thereby obtaining an ultrasound-triggered thermosensitive hydrogel wound dressing.

[0040] Example 2

[0041] This embodiment discloses a hydrogel wound dressing, and the preparation method of the hydrogel wound dressing is as follows:

[0042] S1. Mix a dimethyl sulfoxide solution with a mass fraction of 10% polyethylene glycol diacrylate (PEGDA), a mass fraction of 10% N-isopropylacrylamide (NIPAm) and a mass fraction of 10% acryloxyethyltrimethylammonium chloride (ACB). Then, add azobisisobutyronitrile / disulfiram (AIBN / DS) dropwise into the mixed solution and transfer it to a Schlenk bottle. Degas the solution in the Schlenk bottle through three freeze-thaw cycles, keep the reaction at 70°C for 7h, and stop the reaction by natural cooling. Dialyze with a dialysis bag for 3 days, freeze-dry the obtained dialysate, and obtain a white foam-like product, a quaternary ammonium salt thermosensitive hyperbranched polymer, which is stored in a -20°C refrigerator.

[0043] S2. Prepare an aqueous solution of a quaternary ammonium salt thermosensitive hyperbranched polymer (QTHP), and add a carnosine-zinc ultrasonic responsive piezoelectric MOF sonosensitizer to the aqueous solution to obtain a solution A; the mass percentage concentration of the quaternary ammonium salt thermosensitive hyperbranched polymer in the solution A is 5%; and the concentration of the sonosensitizer is 100 μg / mL.

[0044] S3. Prepare an aqueous solution of thiolated hyaluronic acid, wherein the mass percentage concentration of thiolated hyaluronic acid is 1%, as solution B.

[0045] S4. Solution B is added to solution A. The mass ratio of the quaternary ammonium salt thermosensitive hyperbranched polymer to the thiolated hyaluronic acid in the mixed solution is 1:1. The pH of the mixed solution is adjusted to 8.5. The mixed solution is allowed to stand at 20°C for 3 minutes to form a gel, thereby obtaining an ultrasound-triggered thermosensitive hydrogel wound dressing.

[0046] Example 3

[0047] This embodiment discloses a hydrogel wound dressing, and the preparation method of the hydrogel wound dressing is as follows:

[0048] S1. Mix a dimethyl sulfoxide solution with a mass fraction of 40% polyethylene glycol diacrylate (PEGDA), a mass fraction of 40% N-isopropylacrylamide (NIPAm) and a mass fraction of 40% acryloxyethyl trimethylammonium chloride (ACB). Then, add azobisisobutyronitrile / disulfiram (AIBN / DS) dropwise into the mixed solution and transfer it to a Schlenk bottle. Degas the solution in the Schlenk bottle through three freeze-thaw cycles, keep the reaction at 70°C for 7h, and stop the reaction by natural cooling. Dialyze with a dialysis bag for 3 days, freeze-dry the obtained dialysate, and obtain a white foam-like product, a quaternary ammonium salt thermosensitive hyperbranched polymer, which is stored in a -20°C refrigerator.

[0049] S2. Prepare an aqueous solution of a quaternary ammonium salt thermosensitive hyperbranched polymer (QTHP), and add a carnosine-zinc ultrasonic responsive piezoelectric MOF sonosensitizer to the aqueous solution to obtain a solution A; the mass percentage concentration of the quaternary ammonium salt thermosensitive hyperbranched polymer in the solution A is 50%; and the concentration of the sonosensitizer is 500 μg / mL.

[0050] S3. Prepare an aqueous solution of thiolated hyaluronic acid, wherein the mass percentage concentration of thiolated hyaluronic acid is 1%, as solution B.

[0051] S4. Add solution B to solution A, the mass ratio of quaternary ammonium salt thermosensitive hyperbranched polymer to thiolated hyaluronic acid in the mixed solution is 10:10, adjust the pH of the solution to 8.5, and let it stand at 22°C for 1 min to form a gel, thereby obtaining an ultrasound-triggered thermosensitive hydrogel wound dressing.

[0052] Performance test 1. Determination of properties of hydrogel wound dressing

[0053] In this performance test, the QTHP prepared in Example 1 was dissolved in deuterated water and tested on a 600 MHz nuclear magnetic resonance instrument. Figure 3 H NMR spectrum. Figure 3 , we can see the peaks of hydrogen on the thermosensitive compound monomer and the quaternary ammonium salt compound monomer appear in the H NMR spectrum, proving that QTHP was successfully synthesized. Further, in this performance test, the QTHP prepared in Example 1 and potassium bromide were mixed evenly, ground and pressed into tablets, and the scanning range was 500-4000cm -1 ,get Figure 4 Infrared spectrum. By observing Figure 4 It can be found that the infrared spectrum of QTHP shows characteristic peaks of thermosensitive compound monomers and quaternary ammonium salt compound monomers, proving its successful synthesis, which is consistent with the results of nuclear magnetic hydrogen spectrum analysis.

[0054] In this performance test, the hydrogel wound dressing prepared in Example 1 was frozen with liquid nitrogen and then quenched, freeze-dried at -60° for 24 hours, and the freeze-dried sample was sprayed with gold for 30 seconds and observed under a scanning electron microscope. Figure 6 By observing Figure 6 It can be seen that the hydrogel of the present application has a loose and porous structure.

[0055] This performance test also uses a rheometer to test the storage modulus and loss modulus of the hydrogel wound dressing prepared in Example 1. The test volume is 300ul each time. Figure 7 By observing Figure 7 It can be seen that the storage modulus of the hydrogel wound dressing of the present application is about 100Pa.

[0056] This performance test also tests the acoustic contraction performance of the hydrogel wound dressing prepared in Example 1. Specifically, a culture dish for the hydrogel wound dressing is placed above a medical ultrasound probe, and medical ultrasound (power 1.5 W·cm -2 , frequency 1MHz, duty cycle 50%), ultrasonic treatment for 10min, Figure 8 By observing Figure 8 It can be seen that the hydrogel wound dressing of the present application has good shrinkage performance and can shrink 52.4% of the area in 4 minutes under the action of medical ultrasound.

[0057] Performance Test 2: Antibacterial Test of Hydrogel Wound Dressing

[0058] In this performance test, the hydrogel wound dressing (UTGel) of Example 1 and other samples were mixed with a concentration of 10 8 CFU·mL -1 The mixture was incubated with methicillin-resistant Staphylococcus aureus (MRSA) or Escherichia coli (E. coli) for 60 min, and medical ultrasound (power 1.5 W cm -2 , frequency 1MHz, duty cycle 50%) to trigger the PBS control group and UTGel group for 10min. Take 50μL of each bacterial solution and spread it on LB medium with a diameter of 90mm. Each group has 3 parallel samples and cultured at 37℃ for 24h. The bacterial activity of each group can be judged by the number of colonies coated with bacterial solution after different treatments (PBS buffer group as negative control, H2O2 group as positive control, QTHP group, PBS buffer group triggered by ultrasound, and UTGel group triggered by ultrasound). By observation Fig. 9 It can be found that the hydrogel wound dressing (UTGel) of Example 1 treated with ultrasound has the lowest bacterial activity. In the plate coating experiment, the MRSA activity of this group is only 3.5%, and the E. coli activity is only 13.4%.

[0059] Furthermore, in this performance test, the cylindrical hydrogel wound dressing (UTGel) with a diameter of 6 mm and a height of 5 mm in Example 1 was inoculated with 50 μL of a 10 8 CFU·mL -1 Methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli (E. coli) were cultured on LB medium and medical ultrasound (power 1.5 W cm -2 , frequency 1MHz, duty cycle 50%), followed by incubation at 37℃ for 24h. Fig.10 It can be found that compared with the control group in which agarose was placed, the hydrogel wound dressing of the present application produced antibacterial rings with widths of 6.6 mm and 6.2 mm in the MRSA and E. coli groups, respectively, reflecting excellent antibacterial properties.

Claims

1. A method for preparing a hydrogel wound dressing, characterized in that: The following steps are involved: S1, dispersing polyethylene glycol diacrylate, a temperature-sensitive compound monomer and a quaternary ammonium salt compound monomer in a solvent, adding an initiator, and reacting to obtain a quaternary ammonium salt temperature-sensitive hyperbranched polymer; S2, preparing a quaternary ammonium salt thermosensitive hyperbranched polymer aqueous solution, and dispersing the sonosensitizer therein to obtain a solution A; S3. Using an aqueous solution of thiolated hyaluronic acid as solution B, mixing solution A with solution B, and allowing to stand to form a gel to obtain a hydrogel wound dressing.

2. The method for preparing a hydrogel wound dressing according to claim 1, characterized in that: In step S1, the temperature-sensitive compound monomer is N-isopropyl acrylamide; and the quaternary ammonium salt compound monomer is acryloyloxyethyl trimethyl ammonium chloride.

3. The method for preparing a hydrogel wound dressing according to claim 1, characterized in that: In step S1, the solvent is dimethyl sulfoxide, and the initiator is azobisisobutyronitrile / disulfiram.

4. A method for preparing a hydrogel wound dressing according to any one of claims 1 to 3, characterized in that: In step S1, the mass fraction of the polyethylene glycol diacrylate is 10-40%, the mass fraction of the temperature-sensitive compound monomer is 10-40%, and the mass fraction of the quaternary ammonium salt compound monomer is 10-40%.

5. The method for preparing a hydrogel wound dressing according to claim 1, characterized in that: In the solution A of step S2, the mass percentage concentration of the quaternary ammonium salt thermosensitive hyperbranched polymer is 5-50%; the concentration of the sonosensitizer is 100-500 μg / mL.

6. The method for preparing a hydrogel wound dressing according to claim 1, characterized in that: In step S3, the mass percentage concentration of thiolated hyaluronic acid in solution B is 1-10%.

7. The method for preparing a hydrogel wound dressing according to claim 1, characterized in that: In step S3, the mass ratio of the quaternary ammonium salt thermosensitive hyperbranched polymer to the thiolated hyaluronic acid is (1-10):(1-10).

8. The method for preparing a hydrogel wound dressing according to claim 1, characterized in that: In step S3, the standing gelation conditions are: temperature 20-25° C., time 1-3 min.

9. A hydrogel wound dressing prepared by the preparation method according to any one of claims 1 to 8.

10. Use of the hydrogel wound dressing according to claim 9 in preparing a drug for treating or preventing wounds infected by drug-resistant bacteria.

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