Medical dressing, medical dressing assembly crosslinked with visible light and method for producing same

Abstract

The application discloses a medical dressing crosslinked by visible light, a medical dressing assembly and a preparation method thereof, wherein the medical dressing is in a solution form, and the medical dressing comprises methacrylated apo-lactoferrin, casein, an oxidizing agent and a photosensitizer, wherein the mass concentration of the methacrylated apo-lactoferrin is 0.03-0.07 g / mL; the mass concentration of the casein is 0.03-0.07 g / mL; the molar concentration of the oxidizing agent is 0.05-0.1 mol / L; and the molar concentration of the photosensitizer is 0.005-0.01 mol / L. The medical dressing provided by the application is in-situ photo-cured by visible light, directly forms a protein hydrogel at a target site, realizes rapid sealing of a wound, and insulates potential bacterial pollution, and is convenient to use.

Description

Technical Field

[0001] This application relates to the field of medical materials technology, and in particular to a medical dressing, a medical dressing component, and a method for preparing the same. Background Technology

[0002] In the prior art, there are many hydrogels with at least one function of wound sterilization, anti-inflammation and promoting repair, but different types of hydrogels have their own disadvantages. According to the search, Chinese invention patent application with publication number CN116421775A discloses a lactoferrin gel dressing, which prepares an antibacterial gel by combining lactoferrin-chitosan nanofibers and dopamine-encapsulated graphene oxide fibers. Its antibacterial properties are achieved by adding sustained-release drugs, rather than by the gel itself having antibacterial properties.

[0003] Chinese invention patent application CN116251224A discloses a double-layer dressing comprising an inner layer and an outer layer. The outer layer is a polyurethane film, and the inner layer is a composite gel of betaine-modified hyaluronic acid and lactoferrin. The dressing contains quaternary ammonium salts with antibacterial effects. The hydrogel is formed by vacuum drying, which is time-consuming.

[0004] Chinese invention patent CN106075598B discloses a photocrosslinked sericin protein hydrogel, which uses methacrylic grafts to graft sericin protein to form a hydrogel. This hydrogel is cured by ultraviolet light, which requires a high-quality light source.

[0005] Therefore, there is a need for a hydrogel with excellent antibacterial properties that is also easier to use. Summary of the Invention

[0006] Based on this, a medical dressing that can be cross-linked using visible light, has ideal mechanical properties, and excellent antibacterial properties is provided.

[0007] A medical dressing that utilizes visible light for cross-linking, the medical dressing being in solution form, comprising: methacrylamide lactoferrin, casein, an oxidant, and a photosensitizer, wherein the mass concentration of methacrylamide lactoferrin is 0.03~0.07 g / mL; the mass concentration of casein is 0.03~0.07 g / mL; the molar concentration of the oxidant is 0.05~0.1 mol / L; and the molar concentration of the photosensitizer is 0.005-0.01 mol / L.

[0008] Several alternative methods are provided below, but they are not intended as additional limitations on the overall solution above. They are merely further additions or optimizations. Provided there are no technical or logical contradictions, each alternative method can be combined individually with respect to the overall solution above, or multiple alternative methods can be combined with each other.

[0009] The methacrylamide-derived lactoferrin has a strong ability to bind heme, possessing 7-13 heme binding sites and 14-20 iron ion binding sites. The KD value of the lactoferrin binding heme is 0.015 nM to 2.02 nM. The iron saturation of the methacrylamide-derived lactoferrin is above 10 mg / g. The methacrylamide-derived lactoferrin is obtained by methacrylamide treatment of low-iron-content lactoferrin, using methacrylic anhydride for methacrylation treatment, wherein the grafting rate of methacrylic anhydride is 30%-100%. The low-iron-content lactoferrin refers to lactoferrin with an iron content below 0.15 mg / g. Lactoferrin can be derived from colostrum, milk, and whey of mammals such as cattle, humans, and camels, or it can be recombinant lactoferrin obtained from plant fermentation using genetically engineered bacteria.

[0010] The oxidant is at least one selected from sodium persulfate, ammonium persulfate, and potassium persulfate. The photosensitizer is a terpyridine ruthenium complex. The oxidant and photosensitizer are used to catalyze the methacrylation reaction of lactoferrin and casein; the reaction mechanism is described in [reference needed]. Figure 1a , Figure 1b As shown, methacrylamide lactoferrin and casein undergo a cross-linking reaction under visible light irradiation to form a protein hydrogel.

[0011] The medical dressing provided in this application uses in-situ photocuring to form a protein hydrogel. This protein hydrogel can quickly seal and isolate potential bacterial contamination, and the cross-linking of the hydrogel can be completed in the visible light range (400~760nm wavelength), which greatly reduces the requirements for the light source and makes it more convenient to use.

[0012] Methacrylamide lactoferrin used in medical dressings has a strong adsorption capacity for heme. By adsorbing heme, it cuts off the source of iron that bacteria can obtain, thereby achieving a good antibacterial effect.

[0013] Medical dressings are in solution form. The solvent can be 0.01M phosphate buffer (PBS, pH=7.4) or water. Casein dissolution requires alkaline conditions. Therefore, when preparing the casein solution, adjust the pH to alkaline and promote casein dissolution by stirring at 200~300 rpm.

[0014] In the medical dressing, the mass ratio of methacrylamide lactoferrin to casein is 1:0.1~10. The molar ratio of the oxidant to the photosensitizer is 200:0.25~5. The ratio of methacrylamide lactoferrin to the oxidant is 3~14 g:1 mol.

[0015] Methacrylamide lactoferrin is a component in medical dressings that plays a direct role in antibacterial activity. Its content directly affects the antibacterial effect; a low content may lead to poor antibacterial efficacy. Casein crosslinks with methacrylamide lactoferrin to form a hydrogel, and the casein content affects the mechanical properties of the protein hydrogel. The amounts of the oxidant and photosensitizer are determined based on the amounts of methacrylamide lactoferrin and casein.

[0016] The total concentration of methacrylamide lactoferrin and casein in the medical dressing is 5% to 30%, that is, 0.05 g / mL to 0.3 g / mL. The content of methacrylamide lactoferrin and casein also determines the viscosity of the medical dressing. The viscosity of the medical dressing can be adjusted by adjusting its content within the aforementioned range.

[0017] After the components of the medical dressing are prepared into a solution, they need to be filtered through a filter membrane (filtration pore size of 0.1μm~0.22μm) to remove microorganisms or dust introduced during the preparation process, as well as to remove aggregated or denatured protein particles, so as to obtain a medical dressing that maintains good biological activity and is clean and free of microbial pathogens.

[0018] This application also provides a medical dressing assembly, the medical dressing assembly including a pushing device, the pushing device comprising:

[0019] A first chamber is filled with a first solution containing methacrylamide lactoferrin and casein. The mass concentration of methacrylamide lactoferrin in the first solution is 3-7 g / 100 mL, and the mass concentration of casein is 3-7 g / 100 mL.

[0020] The second chamber is filled with a second solution containing an oxidant and a photosensitizer for catalyzing the reaction of methacrylamide deferroferrin and casein, wherein the volume ratio of the first solution to the second solution is 20:3 to 20:1.

[0021] A switching device for isolating or connecting the first chamber and the second chamber;

[0022] The driving component mixes the solutions in the first and second chambers before outputting them.

[0023] The switching device is a control valve assembly, which controls the isolation and connection status of the first and second chambers. The control valve assembly can be a three-way valve, with its first port connected to the first chamber, its second port connected to the second chamber, and its third port serving as the outflow passage for medical excipients. In use, the control valve assembly connects the first and second chambers, and under the reciprocating action of the drive component, the solutions in the first and second chambers flow and mix, and are then output through the third port of the control valve.

[0024] The switching device is a mixing chamber that is controllably connected to the first chamber and the second chamber. The mixing chamber has an outlet pipe. In use, the driving unit drives the solutions in the first chamber and the second chamber to flow into the mixing chamber simultaneously for mixing, and then outputs them through the process pipe.

[0025] Because the components of medical dressings can cross-link under visible light, they need to be selectively stored separately. This medical dressing assembly provides a storage method where the components are placed in two isolated chambers. The first chamber stores a first solution containing methacrylamide lactoferrin and casein, while the second chamber stores a second solution containing an oxidant and a photosensitizer. When needed, the first and second solutions are mixed in a mixing chamber and then drained through an outlet tube. The mixing chamber can be equipped with partitions or other structures to aid in uniform mixing.

[0026] Optionally, the medical dressing assembly also includes a portable light source for initiating the reaction between methacrylamide lactoferrin and casein.

[0027] The medical dressing provided in this application can undergo a cross-linking reaction using visible light. To accelerate the cross-linking reaction, a more powerful light source can be configured simultaneously to make the cross-linking reaction proceed more rapidly.

[0028] Visible light source power: 3.50~53.5mW / cm² 2 The distance of the light source is 1~5cm, and the illumination time is 30-90s.

[0029] Optionally, the flow rate ratio of the first solution to the second solution into the mixing chamber is 20:3 to 1. The flow rate ratio of the first solution to the second solution into the mixing chamber is consistent with the volume ratio of the first solution to the second solution.

[0030] Optionally, the ratio of methacrylamide lactoferrin in the first solution to photosensitizer in the second solution is 3-14 g: 1 mol.

[0031] Optionally, in the first solution, the mass ratio of methacrylamide lactoferrin to casein is 1:0.5~2.

[0032] Optionally, the oxidant is at least one of sodium persulfate, ammonium persulfate, and potassium persulfate; the photosensitizer is a terpyridine ruthenium complex; and in the second solution, the molar concentration of the oxidant is 0.5~1 mol / L, and the molar concentration of the photosensitizer is 0.05~0.1 mol / L.

[0033] Optionally, in the second solution, the molar ratio of the oxidant to the photosensitizer is 10:0.5~1.5.

[0034] Optionally, the first solution and the second solution are respectively filtered through a filter membrane with a pore size of 0.1 μm to 0.22 μm.

[0035] Optionally, the first solution is obtained by mixing a methacrylamide lactoferrin solution and a casein solution, wherein the mass concentration of the methacrylamide lactoferrin solution is 6-14 g / 100 mL, the mass concentration of the casein solution is 6-14 g / 100 mL, and the volume ratio of the methacrylamide lactoferrin solution to the casein solution is 1:0.5-1.5.

[0036] Optionally, the second solution is obtained by mixing an oxidant solution and a photosensitizer solution, wherein the molar concentration of the oxidant solution is 1~2 mol / L, the molar concentration of the photosensitizer solution is 0.1~0.2 mol / L, and the volume ratio of the oxidant solution to the photosensitizer solution is 20:1~3.

[0037] This application also provides a protein hydrogel for sterilization, wherein the protein hydrogel is formed by curing methacrylamide lactoferrin and casein under visible light in the presence of an oxidant and a photosensitizer.

[0038] The visible light wavelength range for photocuring is 400~760nm. The mass ratio of the methacrylamide-derived lactoferrin to casein is 1:0.1~10. The molar ratio of the oxidant to the photosensitizer is 200:0.25~5. The ratio of the methacrylamide-derived lactoferrin to the oxidant is 3~14g:1mol.

[0039] This application also provides a method for preparing a medical dressing, comprising the following steps:

[0040] A solution of methacrylamide deferroferrin, a solution of casein, an oxidant solution, and a photosensitizer solution are prepared separately. The solutions are then mixed in a predetermined volume ratio to obtain a mixed solution, which is the medical dressing.

[0041] Optionally, the mass concentration of the methacrylamide deferroferrin solution is 6-14 g / mL.

[0042] Optionally, the casein solution has a mass concentration of 6-14 g / mL.

[0043] Optionally, the molar concentration of the oxidant solution is 1~2 mol / L.

[0044] Optionally, the molar concentration of the photosensitizer solution is 0.1~0.2 mol / L.

[0045] Optionally, the volume ratio of the methacrylamide lactoferrin solution, the casein solution, the oxidant solution, and the photosensitizer solution is 150~250:150~250:15~25:1.

[0046] Optionally, the mixed solution can be filtered using a filter membrane to obtain a medical dressing.

[0047] This application also provides a method for in vitro sterilization of the aforementioned medical dressing, wherein after covering the target location with a predetermined amount of medical dressing, visible light with a wavelength of 400~760nm is applied to form a protein hydrogel with bactericidal effect.

[0048] This application also provides a method for in vitro sterilization using the aforementioned medical dressing component, comprising the following steps:

[0049] The driving component pushes the first solution in the first chamber and the second solution in the second chamber into the mixing chamber. After the first solution and the second solution are mixed evenly in the mixing chamber, the medical dressing is output to the target position through the outflow tube.

[0050] After covering the target area with the desired amount of medical dressing, irradiation with visible light at a wavelength of 400~760nm is applied to form a protein hydrogel with bactericidal effect.

[0051] This application provides a wound treatment method, including the following steps:

[0052] The medical dressing is applied to the wound site and then irradiated with visible light at a wavelength of 400-760 nm to form a protein hydrogel.

[0053] The medical dressing completely covers the wound, and visible light is applied for 30 to 90 seconds.

[0054] The medical dressing provided in this application utilizes visible light for in-situ photocuring to directly form a protein hydrogel at the target site, achieving rapid wound closure, isolating potential bacterial contamination, and is easy to use. Among them, methacrylamide lactoferrin has a good heme adsorption capacity, cutting off the source of iron that bacteria can obtain, thereby achieving a good antibacterial effect. Attached Figure Description

[0055] Figure 1a These represent the different states of ruthenium atoms participating in hydrogel solidification in the catalyst;

[0056] Figure 1b The photocuring mechanism of protein hydrogels;

[0057] Figure 2 This is a structural diagram of the extrusion device;

[0058] Figure 3 A schematic diagram illustrating the extrusion of medical dressings by a pushing device;

[0059] Figure 4 The curve showing the change in compressive modulus of the protein hydrogel prepared in Example 1 as a function of irradiation time;

[0060] Figure 5 The curve showing the change in the amount of heme adsorbed by the protein hydrogel prepared in Example 1 over time;

[0061] Figure 6 The antibacterial effect of the protein hydrogel prepared in Example 1;

[0062] Figure 7 The graph shows the iron content in different bacteria after the protein hydrogel prepared in Example 1 was co-incubated with heme.

[0063] Figure 8 The antibacterial activity of the protein hydrogel prepared in Example 1 against different bacteria;

[0064] Figure 9 A graph showing the relationship between different pressures and the depth of indentations formed by different protein hydrogels;

[0065] Figure 10 Compressive modulus diagrams for different protein hydrogels;

[0066] Figure 11 The graph shows the relationship between shear stress and shear strain for different protein hydrogels.

[0067] Figure 12 The shear strength values ​​are for different protein hydrogels;

[0068] Figure 13 Heme adsorption capacity of different protein hydrogels;

[0069] Figure 14 Photographs showing the adsorption of heme on different protein hydrogels;

[0070] Figure 15 Figures showing the antibacterial effects of different protein hydrogels against Staphylococcus aureus;

[0071] Figure 16 Figures showing the antibacterial effects of different protein hydrogels against Escherichia coli;

[0072] Figure 17 Photographs of different protein hydrogels co-cultured with Staphylococcus aureus and Escherichia coli. Detailed Implementation

[0073] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0074] To better describe and illustrate the embodiments of this application, reference may be made to one or more accompanying drawings, but the additional details or examples used to describe the drawings should not be considered as limiting the scope of any of the inventive creations of this application, the embodiments or preferred methods described herein.

[0075] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0076] Preparation of methacrylamide-derived lactoferrin

[0077] The preparation method of methacrylamide-derived lactoferrin includes the following steps:

[0078] (1) Add acetic acid, sodium acetate (molar ratio of 1:1) and EDTA to a PBS solution with pH 2.0 to prepare a mixture, and then dissolve lactoferrin powder (Bega, Australia) in the mixture at room temperature to prepare a lactoferrin solution with a concentration of 0.5 g / 100 mL.

[0079] The mixture contained 0.01 M PBS, 0.1 M acetic acid and sodium acetate, and 500 mM EDTA.

[0080] (2) The lactoferrin solution obtained in step (1) was placed into a dialysis bag and the dialysis bag was placed in PBS solution for dialysis for 72 hours. The retentate after dialysis was pre-frozen at -50°C and then freeze-dried under a vacuum of 1 Pa to obtain a deferroferrin with an iron content of 0.0139 mg / g. The PBS solution was changed continuously during the dialysis process. The concentration of the PBS solution was gradually reduced. The concentration of the PBS solution was gradually reduced from 0.1 M to 0.05 M from 0 to 24 hours, from 0.05 M to 0.01 M from 24 to 48 hours, and from 0.01 M to 0 M from 48 to 72 hours.

[0081] The molecular weight cutoff of the dialysis bag is 3500 Da;

[0082] (3) The deferroferrin obtained in step (2) is subjected to methacrylamide treatment to obtain lactoferrin with strong iron absorption capacity.

[0083] (3.1) Dissolve the aborted lactoferrin in a PBS solution with a pH of 2 at room temperature to prepare a stock solution of aborted lactoferrin with a concentration of 10 g / 100 ml;

[0084] (3.2) Under high-speed stirring at 600 rpm, methacrylic anhydride was added to the defermented lactoferrin stock solution, and then the pH value was adjusted to 7. The reaction was continuously stirred at 25℃ for 2 h. After the reaction, the solution was dialyzed for 48 h, then concentrated by ultrafiltration and filtered twice with a filter membrane with a pore size of 0.22 μm. The filtrate was pre-frozen at -50℃ and then freeze-dried under a vacuum of 1 Pa to obtain lactoferrin with a ferric iron saturation content of 14.43 mg / g and strong iron adsorption capacity.

[0085] The ratio of methacrylic anhydride to lactoferrin is 0.03 mL / 1 g, and the grafting degree of methacryloyl groups on lactoferrin, which has a strong iron-absorbing capacity, is 30%.

[0086] Example 1

[0087] A method for preparing a medical dressing includes the following steps:

[0088] (1) Solution preparation

[0089] Methacrylamide apoferroloferrin (Apo-LfMA) solution: Methacrylamide apoferroloferrin powder (obtained by the aforementioned preparation method) was dissolved in phosphate-buffered saline (PBS) at room temperature to prepare a 10 g / 100 mL solution. Methacrylamide apoferroloferrin is a white powder, readily soluble in water, and dissolves into a transparent, colorless to white liquid.

[0090] Casein solution: Dissolve casein powder in phosphate-buffered saline (PBS) containing 0.1 mol / L sodium hydroxide at room temperature, stirring at 200-300 rpm to prepare a casein solution with a mass concentration of 10 g / 100 mL. Casein is a white powder, soluble in water, and forms a white liquid after dissolution.

[0091] Sodium persulfate (SPS) solution: Dissolve sodium persulfate powder in PBS at room temperature to prepare a sodium persulfate solution with a molar concentration of 1 mol / L. Sodium persulfate is a white powder, readily soluble in water, and forms a transparent, colorless liquid after dissolution.

[0092] Ruthenium tripyridine chloride (Ru) solution: Dissolve ruthenium tripyridine chloride hexahydrate powder in PBS at room temperature to prepare a 0.1 mol / L ruthenium tripyridine chloride solution. Ruthenium tripyridine chloride hexahydrate is an orange-yellow powder, readily soluble in water, and forms an orange-yellow liquid after dissolution.

[0093] (2) Preparation of antibacterial protein pregel solution

[0094] Methacrylamide deferroferrin solution, casein solution, sodium persulfate solution and terpyridine ruthenium chloride solution were thoroughly mixed at a volume ratio of 100:100:20:1. The mixture was then filtered twice using a filter membrane (0.1 μm pore size) to obtain a sterile antimicrobial protein pregel solution.

[0095] (3) Use white visible light (7.5 W / cm²) 2 Irradiate the antimicrobial protein pregel solution for 90 seconds to initiate polymerization of the antimicrobial protein pregel solution to form a hydrogel, solidify and shape it to obtain an antimicrobial protein hydrogel that rapidly adsorbs heme.

[0096] The protein hydrogel prepared in Example 1 was characterized as follows:

[0097] Figure 4 Figure a shows the state of the protein hydrogel (the yellow part within the dashed boundary) without light exposure (in Example 1, the white visible light was the white light emitted by a mobile phone flashlight). It has good fluidity and flows downward under the influence of gravity. The preparation process of the protein hydrogel shown in Figure a is the same as that in Example 1, except that it was not exposed to white visible light. Figure 4 Figure b shows the state of the protein hydrogel (yellow part within the dashed boundary) after 30 seconds of light exposure. Its fluidity has decreased, and it does not flow significantly under the influence of gravity. Figure 4 Figure c shows the compressive modulus of the protein hydrogel under different light exposure durations. The compressive modulus gradually increases with the increase of light exposure time.

[0098] See Figure 5 As shown, the curve of heme adsorption by the protein hydrogel over time is included. Figure 5 As shown in Figure a, the protein hydrogel can rapidly adsorb heme, achieving saturation adsorption within 1 hour. See the photograph of the protein hydrogel before adsorption. Figure 5 Figure b shows a photograph of the protein hydrogel after 24 hours of heme adsorption. Figure 5 As shown in Figure c.

[0099] See Figure 6 As shown, the protein hydrogel exhibits good antibacterial effects against bacteria such as Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and methicillin-resistant Staphylococcus aureus (MRSA).

[0100] See Figure 7 As shown, after bacteria were co-incubated with heme and protein hydrogel in phosphate buffer, the iron content within the bacteria decreased. This indicates that the protein hydrogel, by adsorbing heme, limited the bacteria's uptake of iron from heme. Due to heme starvation, the bacteria were unable to grow and reproduce normally, thus achieving an antibacterial effect. Figure 7 The control group consisted of bacteria incubated in phosphate buffer without heme and protein hydrogel.

[0101] See Figure 8 As shown, the protein hydrogel exhibits good antibacterial effects against several clinically resistant bacteria, including Staphylococcus aureus 25923, Escherichia coli 25922, Pseudomonas aeruginosa 27853, and Acinetobacter baumannii 17978.

[0102] Examples 2-4

[0103] The raw material composition of the protein hydrogels in Examples 2-4 is shown in Table 1.

[0104] Table 1

[0105]

[0106] Medical dressings are cured under visible light to form protein hydrogels. Each component of the medical dressing is prepared into a solution, and the solutions are mixed according to a predetermined volume ratio. The final mixed solution is the medical dressing. The concentrations in Table 1 are the concentrations of each component in the medical dressing. Specifically, component A is the concentration of methacrylamide lactoferrin in the medical dressing; component B is the concentration of casein in the medical dressing; component C is the concentration of methacrylamide lactoferrin in the medical dressing; and component D is the concentration of methacrylamide lactoferrin in the medical dressing.

[0107] In Table 1, LC3:7 indicates that the mass ratio of methacrylamide lactoferrin to casein in medical dressings is 3:7; LC5:5 indicates that the mass ratio of methacrylamide lactoferrin to casein in medical dressings is 5:5; and LC7:3 indicates that the mass ratio of methacrylamide lactoferrin to casein in medical dressings is 7:3.

[0108] The compressive modulus of the protein hydrogel was determined using nanoindentation. The load detected by the nanoprobe when indentations of different depths were created is shown in [reference needed]. Figure 9 As shown, the results of the compression modulus measurement are available in [reference needed]. Figure 10 As shown, the compressive moduli of the protein hydrogels corresponding to LC 3:7, LC 5:5, and LC 7:3 are 15.06±0.5774 kPa, 17.80±0.4990 kPa, and 16.14±0.4890 kPa, respectively. There is no significant difference in the compressive modulus between the protein hydrogels corresponding to LC 3:7 and LC 7:3. The protein hydrogel corresponding to LC 5:5 has a higher compressive modulus, which may be based on its more compact hydrogel structure.

[0109] The characterization results of the shear strength of the protein hydrogel can be found in [reference needed]. Figure 11 , Figure 12 As shown, Figure 11 This represents the relationship between shear stress and shear strain. Figure 12 The shear strength values ​​of the protein hydrogels for different groups are shown. The shear strengths of the protein hydrogels corresponding to LC 3:7 and LC 5:5 are 105.0±3.738 kPa and 94.95±0.8680 kPa, respectively, which are significantly higher than the shear strength of the protein hydrogel corresponding to LC 7:3 (65.69±1.748 kPa). The trend of shear strength variation may be due to the reduction of tyrosine residues in the pre-hydrogel system.

[0110] For the adsorption effect of protein hydrogels on heme, please refer to [reference needed]. Figure 13 , Figure 14 As shown, see Figure 13 As shown, in a 500 μM heme solution, all protein hydrogels reached their maximum heme uptake within 4 hours. However, the protein hydrogels corresponding to LC5:5 and LC7:3 showed significantly faster heme uptake compared to the protein hydrogel corresponding to LC3:7 (reaching 50% of the maximum uptake within 15 minutes). This is because the protein hydrogel corresponding to LC3:7 had a lower content of methacrylamide lactoferrin, resulting in fewer heme-binding capsules in the protein hydrogel network and relatively poorer heme adsorption. Photos of the different groups of protein hydrogels before adsorption, after 1 hour of heme adsorption, and after 24 hours of heme adsorption are shown in [reference needed]. Figure 14As shown, the protein hydrogel corresponding to LC3:7 has a lighter color after 24 hours of heme adsorption, indicating that it adsorbs a smaller amount of heme.

[0111] For the antibacterial effect of protein hydrogels, please refer to [link / reference]. Figure 15 , Figure 16 , Figure 17 As shown, where Figure 15 The results indicate antibacterial activity against Staphylococcus aureus (S. aureus). Figure 16 The antibacterial results against Escherichia coli (E. coli) Figure 17 These are photographs of different groups of protein hydrogels after co-culturing Staphylococcus aureus and Escherichia coli for 12 hours. Figures 15-17 It is evident that in the preliminary in vitro antibacterial experiment, the protein hydrogels corresponding to LC 5:5 and LC 7:3 have similar antibacterial capabilities, killing more than 99% of bacteria within 8 hours, while the protein hydrogel corresponding to LC 3:7 exhibits poor antibacterial performance. The difference in antibacterial performance of the protein hydrogels is related to the content of the effective antibacterial component, methacrylamide lactoferrin.

[0112] Medical dressing components

[0113] The medical dressing assembly includes not only the medical dressing but also a dispensing device. See the structural diagram of the dispensing device. Figure 2 and Figure 3 As shown, the pushing device includes: a first chamber 1 and a second chamber 2 that are isolated from each other; a mixing chamber 3 (i.e., a switching device) that is controllably connected to the first chamber 1 and the second chamber 2; and a driving member 5 that pushes the solutions in the first chamber 1 and the second chamber 2 into the mixing chamber 3 for mixing and then out through the outflow pipe 4.

[0114] The mixing chamber 3 is equipped with an outflow tube 4. When storing or transporting medical dressings, the first chamber 1, the second chamber 2, and the mixing chamber 3 are not connected. When using medical dressings, the mixing chamber 3 is connected to the first chamber 1 and the second chamber 2. The connection between the first chamber 1, the second chamber, and the mixing chamber 3 can be achieved using valves.

[0115] The first chamber 1 and the second chamber 2 have different volumes, and the volume ratio of the first chamber 1 to the second chamber is 20:3~1.

[0116] The first chamber 1 is used to infuse a first solution containing methacrylamide-defermented lactoferrin and casein. The second chamber 2 is used to infuse a second solution containing an oxidant and a photosensitizer for catalyzing the reaction of methacrylamide-defermented lactoferrin and casein. The volume ratio of the first solution to the second solution is 20:3~1.

[0117] In the first solution, the mass concentration of methacrylamide lactoferrin is 3~7 g / 100 mL, and the mass concentration of casein is 3~7 g / 100 mL. In the second solution, the molar concentration of the oxidant is 0.5~1 mol / L, and the molar concentration of the photosensitizer is 0.05~0.1 mol / L.

[0118] When using medical dressings, the mixing chamber 3 is connected to the first chamber 1 and the second chamber 2. The driving component 5 simultaneously pushes the first solution in the first chamber 1 and the second solution in the second chamber 2 into the mixing chamber 3 for mixing. The mixed solution is the medical dressing. The medical dressing is extruded to the target position through the outflow tube 4 and covers an appropriate thickness and area. It is cured by visible light irradiation for 1 to 3 minutes. The irradiation time is related to the power of the light source. In case of urgent curing, the power of the light source can be increased, for example, by using a matching independent light source. In case of non-urgent situations, the flashlight function of a mobile phone can also be used to provide light to complete the light curing.

[0119] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0120] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A medical dressing that utilizes visible light cross-linking, characterized in that, The medical dressing is in solution form and comprises: methacrylamide lactoferrin, casein, an oxidant, and a photosensitizer, wherein the mass concentration of methacrylamide lactoferrin is 0.03~0.07 g / mL; the mass concentration of casein is 0.03~0.07 g / mL; the molar concentration of the oxidant is 0.05~0.1 mol / L; and the molar concentration of the photosensitizer is 0.005-0.01 mol / L.

2. A medical dressing assembly, characterized in that, The medical dressing assembly includes a pushing device, the pushing device comprising: A first chamber is filled with a first solution containing methacrylamide lactoferrin and casein. The mass concentration of methacrylamide lactoferrin in the first solution is 3-7 g / 100 mL, and the mass concentration of casein is 3-7 g / 100 mL. The second chamber is filled with a second solution containing an oxidant and a photosensitizer for catalyzing the reaction of methacrylamide deferroferrin and casein, wherein the volume ratio of the first solution to the second solution is 20:3 to 20:

1. A switching device for isolating or connecting the first chamber and the second chamber; The driving component mixes the solutions in the first and second chambers before outputting them.

3. The medical dressing assembly as described in claim 2, characterized in that, In the first solution, the mass ratio of methacrylamide deferroferrin to casein is 1:0.5~2.

4. The medical dressing assembly as described in claim 2, characterized in that, The oxidant is at least one of sodium persulfate, ammonium persulfate, and potassium persulfate; the photosensitizer is a terpyridine ruthenium complex. In the second solution, the molar concentration of the oxidant is 0.5~1 mol / L, and the molar concentration of the photosensitizer is 0.05~0.1 mol / L.

5. The medical dressing assembly as described in claim 2, characterized in that, In the second solution, the molar ratio of the oxidant to the photosensitizer is 10:0.5~1.

5.

6. The medical dressing assembly as described in claim 2, characterized in that, The first and second solutions were respectively filtered through a filter membrane with a pore size of 0.1 μm to 0.22 μm.

7. A method for preparing a medical dressing as described in claim 1, characterized in that, Includes the following steps: A solution of methacrylamide deferroferrin, a solution of casein, an oxidant solution, and a photosensitizer solution are prepared separately. The solutions are then mixed in a predetermined volume ratio to obtain a mixed solution, which is the medical dressing.

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