QPSF-Ce NPs nanofiber membrane for promoting healing of burn wound and preparation method of QPSF-Ce NPs nanofiber membrane

Abstract

The invention provides a QPSF-Ce NPs nanofiber membrane for promoting healing of burn wounds and a preparation method of the QPSF-Ce NPs nanofiber membrane, and belongs to the field of burn treatment. The nanofiber membrane is composed of QHREDGS, PCL, SF and Ce NPs, cerium, oxygen and carbon elements exist in the nanofiber membrane, and the percentage of cerium atoms is 2-3%; the weight ratio of cerium atoms is 0.5-0.6%, and the proportion of cerium dioxide is 0.7-0.8%. The preparation method comprises the following steps: extracting silk fibroin; a PSF-Ce NPs prefabricated solution is prepared; a PSF-Ce NPs nanofiber membrane is prepared; and treating to obtain the nanofiber membrane with a high-porosity fiber net structure. According to the invention, the QPSF-CeNPs nanofiber membrane with active oxygen scavenging performance is prepared by using an electrostatic spinning technology, and has good biocompatibility, angiogenesis promotion and antibacterial effects.

Description

Technical Field

[0001] The invention belongs to the field of burn treatment, and particularly relates to a QPSF-Ce NPs nanofiber membrane for promoting burn wound healing and a preparation method thereof. Background Art

[0002] The treatment and healing of deep or large burn wounds have always been one of the thorny clinical problems. The healing process of chronic wounds is often delayed or even inhibited by factors such as reactive oxygen species (ROS) accumulation, immune dysfunction, reduced growth factor production, persistent microbial infection, and impaired angiogenesis. Excessive ROS in the wound site will recruit macrophages and polarize them to the M1 type, thereby initiating an uncontrolled inflammatory cycle and increasing the risk of bacterial infection. At the same time, ROS overexpression is not beneficial to angiogenesis, which may be caused by the inactivation of highly oxidative-sensitive enzymes (such as phosphotyrosine phosphatases and sulfhydryl residues) involved in the signaling pathway by high oxidative potential. As a result, the proliferation, migration, and translocation of primitive cells such as fibroblasts and keratinocytes are reduced, ultimately leading to delayed wound healing. Therefore, appropriate adjustment of the unbalanced redox homeostasis can promote angiogenesis, inhibit bacterial infection, and create a suitable microenvironment for accelerating the healing of severe burn wounds.

[0003] Chinese patent CN115645513A (publication date: December 1, 2022) discloses a method for preparing a hydrogel containing Chinese medicine sustained-release particles to promote burn and scald skin repair, as well as its products and applications. The prepared hydrogel can sustainably release Chinese medicine, growth factors, and silk fibroin, and can promote the regeneration of skin cells. The preparation method includes the preparation of Chinese medicine sustained-release particles and the preparation of hydrogel dressings. The advantage is that Fe MOFs has nanoenzyme activity, which can remove excess reactive oxygen produced during skin repair and help restore the skin's redox level. The preparation method provided is simple to operate, and the resulting hydrogel dressing is well stabilized, has antibacterial properties, and is easy to mass-produce. This invention needs further study in promoting angiogenesis.

[0004] Antioxidants have been introduced into various treatment methods as an important means of scavenging ROS to promote the healing of burn wounds, such as cerium oxide nanoparticles (Ce NPs). Previous results have shown that the transition between Ce3+ and Ce4+ oxidation states on the surface of Ce NPs has long-term and effective ROS scavenging ability, and has antibacterial, anti-inflammatory, antioxidant and angiogenic properties. "Hamed Nosrati, Morteza Heydari, Mohammad Khodaei, Cerium oxide nanoparticles: Synthesis methods and applications in wound healing, Materials Today Bio, Volume 23, 2023, 100823, ISSN 2590-0064" discloses the use of scaffolds containing CeO2 NPs for wound healing applications, and under different factors such as concentration, nanoparticle size, exposure time, preparation method, exposure route and cell / tissue type, Ce NPs can easily increase cytotoxicity.

[0005] The cytotoxicity of Ce NPs can be alleviated by using matrix carriers such as hydrogels or membrane delivery systems. The natural fibrous protein silk fibroin (SF) has been approved by the FDA for drug delivery and surgical suture applications and is currently widely used in clinical practice, but SF has the problems of short absorption time, poor mechanical properties, and low spinning ability. Polycaprolactone (PCL), which is also approved by the FDA and widely used in tissue engineering applications, is a biomaterial known for its easy electrospinning. Due to its high hydrophobicity and crystallinity, its cell affinity and biodegradability are affected in vivo. In addition, glutamine-histidine-arginine-glutamic acid aspartic acid-glycine-serine (QHREDGS) is a novel pro-angiogenic peptide that has been reported to promote endothelial cell metabolism, tube formation dynamics, and skin wound healing.

[0006] It is crucial to prepare a suitable matrix carrier and further modify Ce NPs to obtain satisfactory effects, integrate the synergistic effects of ROS scavenging, antibacterial activity, immune metabolism regulation and angiogenesis promotion, and ultimately achieve the purpose of promoting burn wound healing. Summary of the invention

[0007] The invention provides a QPSF-Ce NPs nanofiber membrane for promoting burn wound healing. The nanofiber membrane is composed of QHREDGS, PCL, SF and Ce NPs. The nanofiber membrane is a fiber mesh structure with high porosity, and the fiber diameter is between 0.63±0.05nm.

[0008] Furthermore, the nanofiber membrane contains cerium, oxygen and carbon elements, wherein the atomic percentage of cerium is 2-3%; the weight ratio of cerium atoms is 0.5-0.6%, and the proportion of cerium dioxide CeO2 is 0.7-0.8%.

[0009] A method for preparing a QPSF-Ce NPs nanofiber membrane for promoting burn wound healing comprises the following steps:

[0010] S1. Extracting silk fibroin: boiling silk cocoons in a weak alkaline solution and degumming; hydrolyzing the degummed silk cocoons and filtering and purifying to obtain silk fibroin;

[0011] S2, preparing a PSF-Ce NPs pre-solution; preparing a PCL-Ce NPs solution using Ce NPs and PCL; preparing an SF solution; mixing PCL-Ce NPs and SF in equal proportions to obtain a PSF-Ce NPs solution;

[0012] S3, preparation of PSF-Ce NPs nanofiber membrane: preparation of PSF-Ce NPs nanofiber membrane by electrospinning;

[0013] S4. Processing to obtain QPSF-Ce NPs nanofiber membrane: soaking the PSF-Ce NPs nanofiber membrane obtained in step S3 and then purifying it to obtain a QPSF-Ce NPs nanofiber membrane.

[0014] Furthermore, the step S1 includes the following steps:

[0015] S11, boiling the cocoons in a 0.02-0.05M sodium bicarbonate aqueous solution for 4-5 times, each time for half an hour, and then rinsing with deionized water for 3-5 times to obtain degummed silk;

[0016] S12, dissolving the degummed silk in a 9-10M lithium bromide aqueous solution;

[0017] S13, stirring the solution obtained in step S12 at below 60 degrees for 6-8 hours and dialyzing it in ultrapure water;

[0018] S14. After 3 days, the supernatant was collected by centrifugation and the collected solution was lyophilized to obtain SF.

[0019] Furthermore, the step S2 includes the following steps:

[0020] S21, dissolving Ce NPs in hexafluoroisopropanol at a content of 0.002 g / ml, ultrasonicating for 3-4 min using a high-frequency ultrasonic machine, adding PCL and stirring to form a PCL-Ce NPs solution;

[0021] S22, dissolve SF in hexafluoroisopropanol solution at a concentration of 0.1 mg / ml, and stir at room temperature for 2 days;

[0022] S23, mixing PCL-Ce NPs and SF in equal proportions to obtain a PSF-Ce NPs solution.

[0023] 6 Further, the step S3 comprises the following steps:

[0024] S31, loading the PSF-Ce NPs pre-solution into a syringe with a stainless steel needle;

[0025] S32, under a strong electric field, the PSF-Ce NPs nanofiber membrane is formed on the receiver by the uniform fiber deposition of the ejected fibers;

[0026] S33, placing the obtained PSF-Ce NPs nanofiber membrane in a vacuum drying oven overnight to remove excess solvent.

[0027] Further, the step S4 includes the following steps:

[0028] S41, soaking the PSF-Ce NPs fiber membrane in a phosphate buffered saline solution containing 0.1-0.3 mg / ml QHREDGS for 10 minutes;

[0029] S42. Rinse twice with phosphate buffered saline solution to remove unreacted peptides and obtain a QPSF-Ce NPs composite electrospinning scaffold.

[0030] Furthermore, in step S2, the mass ratio of PCL, SF, and Ce NPs is 50:50:1.

[0031] Furthermore, in step S3, the QPSF-Ce NPs nanofiber membrane has electrostatic capability, with a positive pressure of 15-20 kV and a negative pressure of 1-3 kV.

[0032] Furthermore, in step S3, the spinning injection speed is 0.1-0.3 mm / min, and the distance between the injection needle and the collector is 15-30 cm.

[0033] Compared with the prior art, the advantages and effects of this application are as follows:

[0034] 1. The QPSF-Ce NPs nanofiber membrane provided by the present invention promotes the healing of burn wounds. PCL is introduced into SF to form a matrix carrier, which can overcome the problems of short absorption time and poor mechanical properties of SF, and has good hydrophilicity and high mechanical properties.

[0035] 2. The present invention provides a QPSF-Ce NPs nanofiber membrane for promoting burn wound healing. The nanofiber membrane is fixed with QHREDGS peptide, and Ce NPs are encapsulated into SF / PCL polymer, expressed as QPSF / Ce NPs. It has good biocompatibility and has antioxidant, anti-inflammatory and antibacterial properties for endothelial cells, while promoting cell proliferation, migration and angiogenesis.

[0036] 3. The present invention provides a method for preparing a QPSF-Ce NPs nanofiber membrane for promoting the healing of burn wounds. The prepared nanofiber membrane containing cerium dioxide nanoparticles can significantly accelerate the healing of burn wounds by enhancing epithelialization, dermal maturation, angiogenesis, and reducing scar formation and collagen deposition. It can be used as a relatively ideal skin tissue engineering dressing for clinical tissue healing and regeneration repair of deep and large-area burn wounds.

[0037] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application so that it can be implemented in accordance with the contents of the specification, and to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the following is a detailed description of the preferred embodiments of the present application in conjunction with the accompanying drawings as follows.

[0038] Based on the detailed description of the specific embodiments of the present application in combination with the accompanying drawings below, those skilled in the art will become more aware of the above and other objects, advantages and features of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can also be obtained based on these drawings without creative work. In all drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, each element or part is not necessarily drawn according to the actual scale.

[0040] in:

[0041] Figure 1 This is a flow chart of a method for preparing a QPSF-Ce NPs nanofiber membrane for promoting burn wound healing according to an embodiment of the present invention;

[0042] Figure 2 The electron microscope images and particle size statistics of PSF, PSF-Ce NPs, QPSF, and QPSF-Ce NPs electrospun membranes according to an embodiment of the present invention;

[0043] Figure 3Graphs showing water contact angles of PSF, PSF-Ce NPs, QPSF, and QPSF-Ce NPs electrospun membranes according to an embodiment of the present invention;

[0044] Figure 4 It is a graph of various enzyme activities of PSF, PSF-Ce NPs, QPSF, and QPSF-Ce NPs electrospun membranes according to one embodiment of the present invention;

[0045] Figure 5 This is a graph showing the cell activity results after culturing PSF, PSF-Ce NPs, QPSF, and QPSF-Ce NPs electrospun membranes with fibroblasts according to an embodiment of the present invention;

[0046] Figure 6 Fluorescence images and cell flow cytometry graphs of PSF, PSF-Ce NPs, QPSF, and QPSF-Ce NPs electrospun membranes in one embodiment of the present invention in removing intracellular ROS. Specific embodiments

[0047] To make the purpose, technical scheme and advantages of the embodiment of the present application clearer, the technical scheme in the embodiment of the present application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiment of the present application. Obviously, the described embodiment is a part of the embodiment of the present application, rather than all of the embodiments. In the following description, specific details such as specific configuration and components are provided only to help fully understand the embodiments of the present application. Therefore, it should be clear to those skilled in the art that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present application. In addition, for clarity and brevity, the description of known functions and structures is omitted in the embodiment.

[0048] It should be understood that the references to "one embodiment" or "this embodiment" throughout the specification mean that the specific features, structures, or characteristics associated with the embodiment are included in at least one embodiment of the present application. Therefore, the references to "one embodiment" or "this embodiment" appearing throughout the specification do not necessarily refer to the same embodiment. In addition, these specific features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0049] In addition, the present application may repeat reference numerals and / or letters in different examples. This repetition is for the purpose of simplicity and clarity, and does not in itself indicate the relationship between the various embodiments and / or settings discussed.

[0050] The term "and / or" in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, B exists alone, and A and B exist at the same time. The term " / and" in this article describes another type of association object relationship, indicating that there can be two relationships. For example, A / and B can mean: A exists alone, and A and B exist alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0051] The term "at least one" in this article is merely a description of the association relationship of associated objects, indicating that there may be three relationships. For example, at least one of A and B can mean: A exists alone, A and B exist at the same time, and B exists alone.

[0052] It should also be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusions.

[0053] Example 1

[0054] The present embodiment relates to a QPSF-Ce NPs nanofiber membrane for promoting the healing of burn wounds. The nanofiber membrane is composed of QHREDGS, PCL, SF, and Ce NPs. The nanofiber membrane is a fiber mesh structure with high porosity, and the fiber diameter is between 0.63±0.05 nm.

[0055] Furthermore, the nanofiber membrane contains cerium, oxygen and carbon, with the atomic percentage of cerium being 2.43% and the weight ratio of cerium atoms being 0.59%, which is equivalent to the ratio of cerium dioxide being 0.72%. The ratio of CeO2 proves that Ce NPs have been effectively incorporated into the fiber membrane.

[0056] like Figure 1 As shown, the method for preparing the QPSF-Ce NPs nanofiber membrane for promoting burn wound healing comprises the following steps:

[0057] S1. Extracting silk fibroin: boiling silk cocoons in a weak alkaline solution and degumming; hydrolyzing the degummed silk cocoons and filtering and purifying to obtain silk fibroin;

[0058] S11, boiling the cocoons in a 0.02M sodium bicarbonate aqueous solution for 4 times, each time for half an hour, and then rinsing with deionized water for 3 times to obtain degummed silk;

[0059] S12, dissolving the degummed silk in a 9.3 M lithium bromide aqueous solution;

[0060] S13, stirring the solution obtained in step S12 at 60 degrees for 6 hours and then dialyzing it in ultrapure water with a molecular weight of 3500Da;

[0061] S14. After 3 days, the supernatant was collected by centrifugation, and the collected solution was freeze-dried to obtain a silk sponge.

[0062] S2, preparing a PSF-Ce NPs pre-solution; preparing a PCL-Ce NPs solution using Ce NPs and PCL; preparing an SF solution; mixing PCL-Ce NPs and SF in equal proportions to obtain a PSF-Ce NPs solution;

[0063] S21, dissolving 10 mg of Ce NPs in 5 ml of hexafluoroisopropanol at a content of 0.002 g / ml, ultrasonicating for 3 min using a high-frequency ultrasonic machine, adding 500 mg of PCL and stirring to form a PCL-Ce NPs solution;

[0064] S22, dissolving 500 mg SF in 5 ml hexafluoroisopropanol solution with a content of 0.1 mg / ml, stirring at room temperature for 2 days, wherein the hexafluoroisopropanol content in the hexafluoroisopropanol solution is 0.1 g / ml;

[0065] S23, mixing PCL-Ce NPs and SF in equal proportions to obtain a PSF-Ce NPs solution.

[0066] S3, preparation of PSF-Ce NPs nanofiber membrane: preparation of PSF-Ce NPs nanofiber membrane by electrospinning;

[0067] S31, PSF-Ce NPs pre-solution was loaded into a 10 ml syringe with a 21G stainless steel needle;

[0068] S32, under a strong electric field, the PSF-Ce NPs nanofiber membrane is formed on the receiver by the uniform fiber deposition of the ejected fibers;

[0069] S33, placing the obtained PSF-Ce NPs nanofiber membrane in a vacuum drying oven overnight to remove excess solvent.

[0070] S4. Processing to obtain QPSF-Ce NPs nanofiber membrane: soaking the PSF-Ce NPs nanofiber membrane obtained in step S3 and then purifying it to obtain a QPSF-Ce NPs nanofiber membrane.

[0071] S41, soaking the PSF-Ce NPs fiber membrane in a phosphate buffered saline solution containing 0.1 mg / ml QHREDGS for 10 minutes;

[0072] S42. Rinse twice with PBS to remove unreacted peptides and obtain a QPSF-Ce NPs composite electrospinning scaffold.

[0073] Furthermore, in step S2, the mass ratio of PCL, SF, and Ce NPs is 500 mg: 500 mg: 10 mg.

[0074] Furthermore, in step S3, the QPSF-Ce NPs nanofiber membrane has an electrostatic capability with a positive pressure of 20 kV and a negative pressure of 3 kV.

[0075] Furthermore, in step S3, the spinning injection speed is 0.1-0.3 mm / min, the distance between the injection needle and the collector is 15-30 cm, and the stainless steel needle used is No. 21.

[0076] Technical effect of this embodiment: This embodiment provides a QPSF-Ce NPs nanofiber membrane and a preparation method thereof, wherein the nanofiber membrane has active oxygen scavenging performance and clinical therapeutic potential for promoting the regeneration of acute and chronic damaged skin tissue.

[0077] Control group 1

[0078] This control group is a PSF electrospinning scaffold preparation method, including the following steps:

[0079] S1. Extracting silk fibroin: boiling silk cocoons in a weak alkaline solution and degumming; hydrolyzing the degummed silk cocoons and filtering and purifying to obtain silk fibroin;

[0080] The cocoons were boiled in 0.02M sodium bicarbonate aqueous solution for 4 times, each time for half an hour, and then rinsed with deionized water for 3 times to obtain degummed silk;

[0081] Dissolving the degummed silk in a 9.3 M lithium bromide aqueous solution;

[0082] The solution obtained in step S12 was stirred at 60 degrees for 6 hours and then dialyzed in ultrapure water with a molecular weight of 3500Da;

[0083] After 3 days, the supernatant was collected by centrifugation, and the collected solution was freeze-dried to obtain silk sponge SF.

[0084] S2, preparing a PSF pre-solution; preparing a PCL solution; preparing an SF solution; mixing PCL and SF in equal proportions to obtain a PSF solution;

[0085] 500 mg PCL was dissolved in 5 ml hexafluoroisopropanol solution with a content of 0.1 g / ml, and stirred at room temperature for 2 days. The hexafluoroisopropanol content in the hexafluoroisopropanol solution was 0.1 g / ml;

[0086] Dissolve 500 mg SF in 5 ml hexafluoroisopropanol solution with a content of 0.1 g / ml, and stir continuously at room temperature for 2 days. The hexafluoroisopropanol content in the hexafluoroisopropanol solution is 0.1 g / ml.

[0087] PCL and SF were mixed in equal proportions to obtain PSF solution.

[0088] S3. Preparation of electrospun PSF nanofiber membrane: The prefabricated solution PSF was loaded into a 10 ml syringe with a 21G stainless steel needle, and the PSF nanofiber membrane was formed by the uniform fiber deposition on the receiver under a strong electric field using electrospinning technology. The obtained fiber membrane was placed in a vacuum drying oven overnight to remove excess solvent.

[0089] Control group 2

[0090] This control group is a PSF-Ce NPs electrospinning scaffold preparation method, which includes the following steps:

[0091] S1. Extracting silk fibroin: boiling silk cocoons in a weak alkaline solution and degumming; hydrolyzing the degummed silk cocoons and filtering and purifying to obtain silk fibroin;

[0092] The cocoons were boiled in 0.02M sodium bicarbonate aqueous solution for 4 times, each time for half an hour, and then rinsed with deionized water for 3 times to obtain degummed silk;

[0093] Dissolving the degummed silk in a 9.3 M lithium bromide aqueous solution;

[0094] The solution obtained in step S12 was stirred at 60 degrees for 6 hours and then dialyzed in ultrapure water with a molecular weight of 3500Da;

[0095] After 3 days, the supernatant was collected by centrifugation, and the collected solution was freeze-dried to obtain a silk sponge.

[0096] S2, preparing a PSF-Ce NPs pre-solution; preparing a PCL-Ce NPs solution using Ce NPs and PCL; preparing an SF solution; mixing PCL-Ce NPs and SF in equal proportions to obtain a PSF-Ce NPs solution;

[0097] 10 mg of Ce NPs were dissolved in 5 ml of hexafluoroisopropanol at a content of 0.002 g / ml, sonicated for 3 min using a high-frequency ultrasound machine, and 500 mg of PCL was added and stirred to form a PCL-Ce NPs solution;

[0098] Dissolve 500 mg SF in 5 ml hexafluoroisopropanol solution with a content of 0.1 g / ml, and stir continuously at room temperature for 2 days. The hexafluoroisopropanol content in the hexafluoroisopropanol solution is 0.1 g / ml.

[0099] PCL-Ce NPs and SF were mixed in equal proportions to obtain PSF-Ce NPs solution.

[0100] S3. Preparation of electrospun PSF-Ce NPs nanofiber membrane: The prefabricated solution PSF-Ce NPs was loaded into a 10 ml syringe with a 21G stainless steel needle, and the PSF-Ce NPs nanofiber membrane was formed by the uniform fiber deposition on the receiver under a strong electric field using electrospinning technology. The obtained fiber membrane was placed in a vacuum drying oven overnight to remove excess solvent.

[0101] Control group 3

[0102] This control group is a QPSF electrospinning scaffold preparation method, including the following steps:

[0103] S1. Extracting silk fibroin: boiling silk cocoons in a weak alkaline solution and degumming; hydrolyzing the degummed silk cocoons and filtering and purifying to obtain silk fibroin;

[0104] The cocoons were boiled in 0.02M sodium bicarbonate aqueous solution for 4 times, each time for half an hour, and then rinsed with deionized water for 3 times to obtain degummed silk;

[0105] Dissolving the degummed silk in a 9.3 M lithium bromide aqueous solution;

[0106] The solution obtained in step S12 was stirred at 60 degrees for 6 hours and then dialyzed in ultrapure water with a molecular weight of 3500Da;

[0107] After 3 days, the supernatant was collected by centrifugation, and the collected solution was freeze-dried to obtain silk sponge SF.

[0108] S2, preparing a PSF pre-solution; preparing a PCL solution; preparing an SF solution; mixing PCL and SF in equal proportions to obtain a PSF solution;

[0109] 500 mg PCL was dissolved in 5 ml hexafluoroisopropanol solution with a content of 0.1 g / ml, and stirred at room temperature for 2 days. The hexafluoroisopropanol content in the hexafluoroisopropanol solution was 0.1 g / ml;

[0110] Dissolve 500 mg SF in 5 ml hexafluoroisopropanol solution with a content of 0.1 g / ml, and stir continuously at room temperature for 2 days. The hexafluoroisopropanol content in the hexafluoroisopropanol solution is 0.1 g / ml.

[0111] PCL and SF were mixed in equal proportions to obtain PSF solution.

[0112] S3. Preparation of electrospun PSF nanofiber membrane: The prefabricated solution PSF was loaded into a 10 ml syringe with a 21G stainless steel needle, and the PSF nanofiber membrane was formed by the uniform fiber deposition on the receiver under a strong electric field using electrospinning technology. The obtained fiber membrane was placed in a vacuum drying oven overnight to remove excess solvent.

[0113] S3. Soak the fiber membrane PSF nanofiber membrane in a phosphate buffered saline solution containing 0.1 mg / ml QHREDGS for 10 minutes. Rinse twice with the phosphate buffered saline solution to remove unreacted polypeptides. Obtain the QPSF electrospinning scaffold.

[0114] Example 2

[0115] This example relates to the PSF, PSF-Ce NPs, QPSF, and QPSF-Ce NPs nanofiber membranes prepared in the above examples and control groups, such as Figure 2 The electron microscope images and particle size statistics of PSF, PSF-Ce NPs, QPSF, and QPSF-Ce NPs nanofiber membranes are shown respectively. The QPSF-Ce NPs electrospun membrane has a fiber network structure with high porosity, and the fiber diameter is between 0.63±0.05nm.

[0116] Example 3

[0117] This embodiment relates to the PSF, PSF-Ce NPs, QPSF, QPSF-Ce NPs nanofiber membranes in the above embodiments and control groups, such as Figure 3 The water contact angles of the QPSF nanofiber membrane, QPSF-Ce NPs nanofiber membrane, PSF nanofiber membrane and PSF / Ce NPs nanofiber membrane were 97.1±6°, 80.35±11.05°, 126.8±0.4° and 129.2±1.3°, respectively. After the QPSF and QPSF-Ce NPs nanofiber membranes were loaded with QHREDGS peptide, their hydrophilicity increased compared with that of the PSF and PSF / Ce NPs nanofiber membranes containing high PCL content, and their contact angles decreased by more than 23% and 38%, respectively.

[0118] Technical effect of this embodiment: This embodiment proves that the QPSF-Ce NPs nanofiber membrane has good hydrophilicity.

[0119] Example 4

[0120] This embodiment relates to the PSF, PSF-Ce NPs, QPSF, QPSF-Ce NPs nanofiber membranes in the above embodiments and control groups, such as Figure 4The scavenging capacity of PSF and QPSF nanofiber membranes for DPPH radicals was 20%, and after Ce NPs were added to the QPSF nanofiber membrane, this scavenging capacity increased to about 75%. This shows that CeNPs have the effect of scavenging DPPH radicals. In addition, compared with the nanofiber membrane without CeNPs, QPSF and QPSF-CeNPs nanofiber membranes can remove 50% of O 2 or H2O2.

[0121] Technical effect of this embodiment: The experimental results of this embodiment show that QPSF-CeNPs nanofiber membrane exhibits anti-inflammatory properties by regulating the phenotype of macrophages from M1 to M2, and has the effects of promoting angiogenesis, downregulating inflammatory factors, enhancing collagen deposition and antibacterial effects.

[0122] Example 5

[0123] This embodiment relates to the PSF, PSF-Ce NPs, QPSF, and QPSF-Ce NPs nanofiber membranes in the above embodiments and the control group. Five identical RAT-1 cell culture dish samples were prepared, and four of the samples were placed with PSF, PSF-CeNPs, QPSF, and QPSF-Ce NPs nanofiber membranes, respectively. One sample was not added with any nanofiber membrane as the control group, and all were subjected to cell live / dead staining detection. Figure 5 The figure shows the viability of RAT-1 cells after treatment with PSF, PSF-Ce NPs, QPSF, QPSF-CeNPs nanofiber membrane and control group respectively. A large number of green fluorescent cells in the five sample groups represent live cells, and a small number of red fluorescent cells represent dead cells. The results show that the RAT-1 cell culture dish samples placed in the QPSF-CeNPs nanofiber membrane are basically live cells, with the most live cells compared to the other four samples.

[0124] Technical effect of this embodiment: The experimental results of this embodiment show that the QPSF-CeNPs nanofiber membrane has good cell compatibility.

[0125] Example 6

[0126] This embodiment relates to the PSF, PSF-Ce NPs, QPSF, QPSF-Ce NPs nanofiber membranes in the above embodiments and control groups, such as Figure 6As shown, the antioxidant therapeutic effect of QPSF-CeNPs nanofiber membrane can be seen. Six identical RAT-1 cell culture dish samples were prepared, and four of them were placed in PSF, PSF-Ce NPs, QPSF, and QPSF-Ce NPs nanofiber membranes, respectively. These four samples and a blank RAT-1 cell culture dish sample were exposed to H2O2 to establish an oxidative stress microenvironment. The remaining sample was not added with any nanofiber membrane and was not exposed to H2O2 as a control group.

[0127] First, specific immunofluorescence analysis and flow cytometry (FCM) were used to quantitatively evaluate the level of ROS in RAT-1 cells under different treatments. Compared with cells treated with PSF-CeNPs, QSPF, and SPF nanofiber membranes, cells treated with QPSF-CeNPs showed reduced fluorescence intensity, indicating potential relief of oxidative stress and cell damage, and the blank group had the highest fluorescence intensity. In addition, FCM analysis was used to quantitatively evaluate the generation of ROS in RAT-1 cells of different samples, and the results were consistent with the fluorescence results.

[0128] Technical effect of this embodiment: The QPSF-CeNPs nanofiber membrane prepared by the electrospinning technology of the present invention has the performance of scavenging active oxygen.

[0129] The above description is only the preferred embodiment of the present invention, which does not limit the protection scope of the present invention. For those skilled in the art, the present invention can be modified and varied in various ways. Within the spirit and principle of the present invention, any change, modification, replacement, integration and parameter change of these embodiments by conventional substitution or capable of achieving the same function without departing from the principle and spirit of the present invention shall fall within the protection scope of the present invention.

Claims

1. A QPSF-Ce NPs nanofiber membrane for promoting burn wound healing, characterized in that: The nanofiber membrane is composed of QHREDGS, PCL, SF, and Ce NPs; the nanofiber membrane is a fiber mesh structure with high porosity, and the fiber diameter is between 0.63±0.05nm.

2. The QPSF-Ce NPs nanofiber membrane for promoting burn wound healing according to claim 1, characterized in that: The nanofiber membrane contains cerium, oxygen and carbon elements, wherein the atomic percentage of cerium is 2-3%, the weight ratio of cerium atoms is 0.5-0.6%, and the proportion of cerium dioxide CeO2 is 0.7-0.8%.

3. The method for preparing a QPSF-Ce NPs nanofiber membrane for promoting burn wound healing according to claim 2, characterized in that: The following steps are involved: S1. Extracting silk fibroin: boiling silk cocoons in a weak alkaline solution and degumming; hydrolyzing the degummed silk cocoons and filtering and purifying to obtain silk fibroin; S2, preparing a PSF-Ce NPs pre-solution; preparing a PCL-Ce NPs solution using Ce NPs and PCL; preparing an SF solution; mixing PCL-Ce NPs and SF in equal proportions to obtain a PSF-Ce NPs solution; S3, preparation of PSF-Ce NPs nanofiber membrane: preparation of PSF-Ce NPs nanofiber membrane by electrospinning; S4. Processing to obtain QPSF-Ce NPs nanofiber membrane: soaking the PSF-Ce NPs nanofiber membrane obtained in step S3 and then purifying it to obtain a QPSF-Ce NPs nanofiber membrane.

4. The method for preparing a QPSF-Ce NPs nanofiber membrane for promoting burn wound healing according to claim 3, characterized in that: The step S1 comprises the following steps: S11, boiling the cocoons in a 0.02-0.05M sodium bicarbonate aqueous solution for 4-5 times, each time for half an hour, and then rinsing with deionized water for 3-5 times to obtain degummed silk; S12, dissolving the degummed silk in a 9-10M lithium bromide aqueous solution; S13, stirring the solution obtained in step S12 at below 60 degrees for 6-8 hours and dialyzing it in ultrapure water; S14. After 3 days, the supernatant was collected by centrifugation and the collected solution was lyophilized to obtain SF.

5. The method for preparing a QPSF-Ce NPs nanofiber membrane for promoting burn wound healing according to claim 4, characterized in that: The step S2 comprises the following steps: S21, dissolving Ce NPs in hexafluoroisopropanol at a content of 0.002 g / ml, ultrasonicating for 3-4 min using a high-frequency ultrasonic machine, adding 0.1 g / ml PCL and stirring to form a PCL-Ce NPs solution; S22, dissolve SF in hexafluoroisopropanol solution at a content of 0.1 g / ml, and stir continuously at room temperature for 2 days; S23, mixing PCL-Ce NPs and SF in equal proportions to obtain a PSF-Ce NPs solution.

6. The method for preparing a QPSF-Ce NPs nanofiber membrane for promoting burn wound healing according to claim 5, characterized in that: The step S3 comprises the following steps: S31, loading the PSF-Ce NPs pre-solution into a syringe with a stainless steel needle; S32, under a strong electric field, the PSF-Ce NPs nanofiber membrane is formed on the receiver by the uniform fiber deposition of the ejected fibers; S33, placing the obtained PSF-Ce NPs nanofiber membrane in a vacuum drying oven overnight to remove excess solvent.

7. The method for preparing a QPSF-Ce NPs nanofiber membrane for promoting burn wound healing according to claim 6, characterized in that: The step S4 comprises the following steps: S41, soaking the PSF-Ce NPs fiber membrane in a phosphate buffered saline solution containing 0.1-0.3 mg / ml QHREDGS for 10 minutes; S42. Rinse twice with phosphate buffered saline solution to remove unreacted peptides and obtain a QPSF-Ce NPs composite electrospinning scaffold.

8. The method for preparing a QPSF-Ce NPs nanofiber membrane for promoting burn wound healing according to claim 3 or 5, characterized in that: In the step S2, the mass ratio of PCL, SF and Ce NPs is 50:50:

1.

9. The method for preparing a QPSF-Ce NPs nanofiber membrane for promoting burn wound healing according to claim 3 or 6, characterized in that: In step S3, the positive pressure of the QPSF-Ce NPs nanofiber membrane is 15-20 kV, and the negative pressure is 1-3 kV.

10. The method for preparing a QPSF-Ce NPs nanofiber membrane for promoting burn wound healing according to claim 3 or 6, characterized in that: In the step S3, the spinning injection speed is 0.1-0.3 mm / min, and the distance between the injection needle and the collector is 15-30 cm.

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