Natural spider silk-based self-adaptive surgical suture and preparation method thereof
By physically regulating spider silk to form a nanofiber structure, the problem of unadjustable tension in existing suture materials under physiological conditions has been solved, achieving adaptive suture tension adjustment and improving biocompatibility and healing quality.
Patent Information
- Application Number
- CN202610121469.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-29
- Publication Date
- 2026-04-21
AI Technical Summary
Existing surgical suture materials struggle to balance mechanical properties with tissue adaptability, cannot dynamically adjust suture tension, and have limited biocompatibility and long-term safety, leading to local stress concentration and inflammatory reactions.
By performing water balance treatment, axial stretching, and annealing on natural spider silk, a highly oriented ultrafine nanofiber structure is formed, enabling the suture to adaptively shrink under humidity and body fluid stimulation, and dynamically adjust the suture tension.
While maintaining high strength and toughness, the suture can adaptively adjust the tension under physiological conditions, promote tissue alignment and repair, reduce local stress concentration, and improve healing quality.
Smart Images
Figure CN121891585A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of biomedical materials technology, specifically relating to an adaptive surgical suture based on natural spider silk and its preparation method. Background Technology
[0002] Surgical sutures are among the most fundamental and critical medical consumables used in surgery. Their main function is to provide necessary mechanical support to damaged tissues after surgery to facilitate wound closure and tissue repair. Ideal surgical sutures should provide continuous and stable tension support during wound healing, while also possessing good biocompatibility and tissue adaptability to avoid local ischemia, inflammatory reactions, or delayed healing caused by tension mismatch or material irritation.
[0003] Currently, widely used surgical sutures in clinical practice mainly include synthetic polymer sutures such as nylon, polypropylene, polyester, and polylactic acid, as well as sutures derived from natural sources such as silk fibroin and collagen. These sutures typically provide sufficient mechanical strength to maintain tissue occlusion during the initial suturing stage. However, their mechanical behavior is primarily passive, meaning the suture length and tension are essentially fixed after suturing and difficult to dynamically adjust with postoperative tissue swelling, retraction, and healing progress. In practical applications, this unadjustable tension characteristic can easily lead to localized stress concentration at the suture site, thus affecting tissue blood supply and repair quality. Furthermore, some synthetic polymer sutures persist in the body for extended periods, potentially causing foreign body irritation or chronic inflammatory reactions, limiting their application in certain tissue suturing procedures.
[0004] Spider silk, as a natural protein fiber material, has attracted widespread attention due to its excellent mechanical properties, biocompatibility, and biodegradability. Existing research shows that the tensile strength of different types of spider traction silk can typically reach above 1.0 GPa, with some high-performance spider silks reaching approximately 1.6 GPa and a tensile toughness exceeding 300 MJ·m⁻³, exhibiting both high strength and high toughness. Furthermore, the spider silk-based natural material suture in this invention also exhibits typical humidity-responsive behavior, undergoing significant axial shrinkage and generating considerable shrinkage stress in high-humidity environments, providing a potential foundation for its application in functional fibers and smart materials.
[0005] Existing research on spider silk largely focuses on its natural structural characteristics, humidity-driven shrinkage mechanism, and basic mechanical behavior characterization, or on preparing spider silk-like materials through chemical modification and recombinant protein spinning. These technical approaches often rely on exogenous chemical reagents or complex processing, which to some extent weakens the material's biocompatibility and degradation advantages. This invention targets natural spider silk, using purely physical means to regulate its internal protein chain structure and nanofiber orientation to achieve a synergistic improvement in macroscopic mechanical properties and environmental responsiveness, and directly applies it to the field of surgical sutures with dynamic tension regulation capabilities. Summary of the Invention
[0006] The purpose of this invention is to overcome the problems of existing surgical suture materials, such as the difficulty in balancing mechanical properties and tissue adaptability, the inability to dynamically adjust suture tension, and limitations in biocompatibility and long-term safety. Addressing the practical needs of tissue deformation and stress changes during wound healing under complex physiological environments, this invention provides a natural spider silk-based adaptive surgical suture and its preparation method. This suture maintains high strength and toughness while exhibiting adaptive contraction behavior under physiological stimuli such as body fluids and humidity. Even after contraction, the suture retains its objective elasticity and mechanical properties, thereby achieving dynamic adjustment of suture tension and promoting the alignment and repair of various tissues.
[0007] The technical solution of this invention is: This invention uses natural spider silk as raw material. Through sequential water balancing, axial stretching, and annealing treatments, the internal silk protein molecular chain structure of the spider silk is regulated, causing it to form a highly oriented ultrafine nanofiber structure under axial stress. This improves the mechanical properties of the spider silk and its responsiveness to environmental changes on a macroscopic scale. The spider silk treated in this way can undergo axial super-shrinkage behavior and generate corresponding shrinkage stress in high-humidity environments, providing a functional basis for its use as an adaptive surgical suture.
[0008] In a first aspect, the present invention provides a method for preparing a natural spider silk-based adaptive surgical suture, comprising the following steps: Step 1: Select a round-bellied spider (Orbicularis orbiformis) Araneus ventricosus Spiders were raised in closed containers as a source of spider silk. Continuous natural spider silk fibers were extracted from the spiders' bodies by forced silk-spinning at a constant traction speed of approximately 4 cm / s. The extracted spider silk was fixed on a support and stored in an environment with a temperature of 25°C and a relative humidity of less than 25% to obtain initial spider silk samples.
[0009] Step 2: Fix both ends of the spider silk obtained in Step 1 to the frame and place it in an environment with a relative humidity of 25% to 100% for humidity equilibration treatment without free shrinkage. The humidity equilibration treatment time is 1 to 5 days to allow water molecules to penetrate into the amorphous regions inside the spider silk, thereby improving the conformational flexibility of the silk protein molecular chains. In this step, the humidity equilibration treatment is preferably carried out in an environment with a relative humidity of 40% to 80%.
[0010] Step 3: After completing the humidity balancing treatment, apply a predetermined tensile strain to the spider silk along its axis to cause the spider silk to be stretched and oriented under stress, thereby inducing the internal nanofibers and silk protein molecular chains to align along the axis. The tensile strain is 10% to 80%, and the stretching time is 0.5 to 6 hours.
[0011] Step 4: While maintaining the axial tensile strain, the spider silk is annealed in a vacuum or inert atmosphere for shaping. The annealing temperature is from room temperature to 150°C, and the annealing time is 0.5 to 6 hours. This allows the internal orientation structure of the spider silk to stabilize and solidify after moisture removal, resulting in spider silk fibers that have undergone tensile orientation annealing. In this step, the annealing temperature is preferably from room temperature to 60°C to limit the length of the spider silk during drying, thus maintaining the axial pre-strain.
[0012] Step 5: Arrange multiple spider silk fibers treated in Step 4 in parallel according to a predetermined number and twist them to form a suture body with a yarn structure. The number of spider silk fibers is 100 to 1000, so as to obtain a natural spider silk-based adaptive surgical suture with both mechanical strength and flexibility.
[0013] Secondly, the present invention provides a natural spider silk-based adaptive surgical suture prepared by the above method.
[0014] Preferably, the surgical suture is made of natural spider silk. After moisture regulation treatment, the natural spider silk is subjected to restricted drying and shaping under axial pre-strain, which causes the protein chains inside the spider silk to rearrange in an orderly manner and form a highly oriented nanofiber structure. The surgical suture can generate axial contraction stress in a moist physiological environment, thereby achieving adaptive adjustment of the tension at the suture site.
[0015] Preferably, the nanofiber structure is composed of highly axially oriented ultrafine nanofibers inside the surgical suture, and the average diameter of the nanofibers is less than 50 nm.
[0016] Preferably, under the effects of moisture regulation and axial pre-strain, the spider silk exhibits an increased β-sheet structure content and a decreased α-helical structure content in its protein chains, thereby improving the mechanical properties and environmental responsiveness of the suture.
[0017] Preferably, the surgical suture has a breaking strength of not less than 1.5 GPa and a breaking elongation of 50%; the axial shrinkage stress generated by the surgical suture under conditions of increased humidity is not less than 90 MPa.
[0018] Thirdly, the present invention provides the use of the above-described natural spider silk-based adaptive surgical suture in surgical suturing.
[0019] Advantages and beneficial effects of the present invention: 1. This invention uses natural spider silk as raw material and employs a combination of water balance treatment, axial stretching and orientation, and annealing to regulate the molecular chain structure of silk protein inside the spider silk. This improves the material properties without introducing chemical modifiers and maintains the good biocompatibility and biosafety of natural spider silk.
[0020] 2. This invention introduces a relative humidity control range of 25% to 100% during the humidity balancing stage, an axial strain range of 10% to 80% during the stretching stage, and provides temperature and time variation space during the annealing stage. This gives the preparation method a clear and adjustable process window, avoiding the limitation of existing technologies that can only achieve performance improvement under a single condition, and enhancing the feasibility and versatility of the method.
[0021] 3. Spider silk treated by the method of the present invention can form a highly oriented ultrafine nanofiber structure. On a macroscopic scale, the single filament can simultaneously possess high mechanical strength, good flexibility, and responsiveness to humid environments, enabling the resulting surgical sutures to exhibit axial contraction behavior in the in vivo environment, thus providing a material basis for achieving adaptive suture tension.
[0022] 4. This invention obtains surgical sutures with a yarn structure by arranging multiple treated spider silk fibers in parallel and twisting them into a thread. The structural parameters of the sutures can be adjusted according to actual needs, thereby balancing operability and mechanical load-bearing capacity, and meeting the surgical suturing needs of different tissue types and different wound sizes.
[0023] 5. The natural spider silk-based adaptive surgical suture prepared by this invention can be used in various surgical applications, including skin tissue and internal organ tissue. It can participate in the dynamic adjustment of suture tension in the moist physiological environment after surgery and has the characteristic of gradual and mild biodegradation over time. This helps to reduce local stress concentration, improve wound closure stability and tissue healing quality, and has good clinical application prospects. Attached Figure Description
[0024] Figure 1 A schematic diagram illustrating how the structure and mechanical properties of natural spider silk are enhanced by adjusting the nanofibers, specifically by regulating the flexibility of protein chains to modulate spider silk nanofibers.
[0025] Figure 2 Mechanical properties of monofilaments under different pre-strain conditions after vacuum drying at room temperature for 2 hours. The tensile rate during mechanical testing was 500 mm / min, the relative humidity was 35%, and the filament diameter was 3.5 ± 0.5 µm.
[0026] Figure 3 Mechanical properties at 25% pre-tension strain at room temperature for different times. The tensile rate during mechanical testing was 500 mm / min, the relative humidity was 35%, and the wire diameter was 3.5 ± 0.5 µm.
[0027] Figure 4 Mechanical properties of monofilaments vacuum-dried for 2 hours at different annealing temperatures. The tensile rate during mechanical testing was 500 mm / min, the relative humidity was 35%, and the filament diameter was 3.5 ± 0.5 µm.
[0028] Figure 5 Cell compatibility (a) and blood compatibility (b) of the surgical sutures in this invention.
[0029] Figure 6 The surgical sutures used in this invention for suturing the skin and their degradation are explained.
[0030] Figure 7 The surgical sutures used in this invention are explained in terms of their role in suturing the stomach's support structure.
[0031] Figure 8 The recovery and biodegradation of the stomach after surgical suture closure in this invention are described. Detailed Implementation
[0032] The technical solution of the present invention will be further illustrated below through embodiments.
[0033] Example 1: Preparation method of natural spider silk-based adaptive surgical suture This embodiment provides a monofilament achieving a breaking strength of 2.0 GPa and a tensile strength of 480 MJ / m. −3 A method for preparing a natural spider silk-based adaptive surgical suture with high toughness and a driving stress of 92.6 MPa is described, with appendix. Figure 1 This is a schematic diagram illustrating how this type of method modifies and enhances the structure and mechanical properties of natural spider silk, specifically including the following steps: Step 1: Select the round-bellied spider ( Araneus ventricosus Spiders were raised in closed containers as a source of spider silk. Natural spider silk fibers were continuously extracted from the spider's body using a forced silk-spinning method at a traction speed of approximately 4 cm / s. The extracted spider silk was fixed to a support and stored in an environment with a temperature of 25 ℃ and a relative humidity of 10% to obtain initial spider silk samples.
[0034] Step 2: Fix both ends of the spider silk obtained in Step 1 to the frame and perform humidity balancing treatment in an environment with a relative humidity of 60% for 3 days to allow water molecules to fully enter the amorphous region inside the spider silk, thereby improving the conformational flexibility of the silk protein molecular chains.
[0035] Step 3: After completing the humidity balancing treatment, apply a predetermined tensile strain of 25% along the axis of the spider silk to cause the spider silk to undergo orientation stretching under stress, thereby inducing the internal nanofibrils and protein chains to align along the axis.
[0036] Step 4: While keeping the axial pre-strain constant, place the spider silk in a vacuum environment and dry it at room temperature for 2 hours. This allows the internal orientation structure of the spider silk to be stabilized and solidified after the moisture is removed, resulting in spider silk fibers that have undergone pre-strain vacuum drying treatment.
[0037] Step 5: Arrange multiple spider silk fibers treated in Step 4 in parallel according to a predetermined number and twist them to form a yarn structure. The number of spider silk fibers is 500, thereby producing a natural spider silk-based adaptive surgical suture with good flexibility and mechanical load-bearing capacity.
[0038] Example 2: Preparation of natural spider silk-based adaptive surgical sutures under different axial pre-strain conditions This embodiment provides a method for preparing natural spider silk-based adaptive surgical sutures under different axial pre-strain conditions. Figure 2 The graph shows the variation of the mechanical properties of a single filament under different pre-strains. Figure 3 The graph shows the changes in the mechanical properties of a monofilament under different pre-stretch strain times.
[0039] Steps 1-2: Following the methods in Steps 1 and 2 of Example 1, obtain natural spider silk and perform initial preservation and humidity balancing treatment.
[0040] Step 3: After completing the humidity balancing treatment, apply a tensile strain (10%-80%) different from that in Example 1 to the spider silk along its axis, so that the spider silk undergoes orientation stretching under stress (0.5-6 hours), but its orientation degree is different from that of the spider silk obtained in Example 1.
[0041] Step 4: While keeping the axial pre-strain constant, place the spider silk treated in Step 3 in a vacuum environment and dry it at room temperature for 2 hours to allow the internal structure of the spider silk to complete orientation curing under the strain conditions.
[0042] Step 5: Arrange the multiple spider silk fibers processed in step 4 in parallel according to a predetermined number and twist them to form a natural spider silk-based surgical suture structure. The remaining operations are the same as in Example 1.
[0043] The natural spider silk-based surgical sutures prepared by the above method can also exhibit axial contraction behavior in a humid environment, but the degree of contraction and mechanical response change with the applied axial pre-strain.
[0044] Example 3: Preparation of natural spider silk-based adaptive surgical sutures under different humidity balance conditions This embodiment provides a method for preparing natural spider silk-based adaptive surgical sutures under different humidity balance conditions.
[0045] Step 1: Following the method in Step 1 of Example 1, select the round-bellied spider as the source of spider silk, obtain natural spider silk by forced silk spinning, and initially preserve it in an environment with a temperature of 25 ℃ and a relative humidity of 10%.
[0046] Step 2: Fix both ends of the spider silk obtained in Step 1 to the frame and process it under humidity balancing conditions different from those in Example 1, wherein the relative humidity is 25%-100% and the humidity balancing treatment time is 1-5 days, so that the internal moisture balance of the spider silk is different from that in Example 1.
[0047] Step 3: After completing the humidity balancing treatment, apply a predetermined tensile strain to the spider silk along its axial direction to cause the spider silk to undergo oriented stretching under stress. The application method is the same as in Example 1.
[0048] Step 4: While keeping the axial pre-strain constant, place the spider silk in a vacuum environment and dry it at room temperature for 2 hours. This allows the internal orientation structure of the spider silk to be stabilized and solidified after the moisture is removed, resulting in spider silk fibers that have undergone pre-strain vacuum drying treatment.
[0049] Step 5: Arrange the multiple spider silk fibers processed in step 4 in parallel according to a predetermined number and twist them to form a natural spider silk-based surgical suture structure. The remaining operations are the same as in Example 1.
[0050] The natural spider silk-based surgical sutures prepared by the above method can exhibit axial shrinkage behavior in a humid environment, and their shrinkage characteristics change with different humidity balance treatment conditions.
[0051] Example 4: Preparation of natural spider silk-based adaptive surgical sutures under different annealing parameters This embodiment provides a method for preparing natural spider silk-based adaptive surgical sutures under different annealing conditions. Figure 4 The graph shows the changes in the mechanical properties of monofilaments after vacuum drying for 2 hours at different annealing temperatures.
[0052] Steps 1 to 3: Following the methods in Steps 1 to 3 of Example 1, obtain natural spider silk and perform initial preservation and humidity balancing treatment, and then stretch and orient it.
[0053] Step 4: While keeping the axial pre-strain constant, place the spider silk treated in Step 3 in a vacuum environment and dry it at room temperature to 150°C for annealing and drying time of 0.5 to 6 hours, so that the internal structure of the spider silk can be oriented and cured under the strain conditions.
[0054] Step 5: Arrange the multiple spider silk fibers processed in step 4 in parallel according to a predetermined number and twist them to form a natural spider silk-based surgical suture structure. The remaining operations are the same as in Example 1.
[0055] Example 5: Preparation of natural spider silk-based adaptive surgical sutures with different suture structure parameters This embodiment provides a method for preparing natural spider silk-based adaptive surgical sutures under different suture structure parameters.
[0056] Step 1: Following the method in Step 1 of Example 1, select the round-bellied spider as the source of spider silk, obtain natural spider silk by forced silk spinning, and initially preserve it in an environment with a temperature of 25 ℃ and a relative humidity of 10%.
[0057] Step 2: Fix both ends of the spider silk obtained in Step 1 to the frame and perform humidity balancing treatment in an environment with a relative humidity of 60% for 3 days to allow the internal moisture of the spider silk to reach a balanced state. The treatment method is the same as in Example 1.
[0058] Step 3: After completing the humidity balancing treatment, apply a predetermined tensile strain to the spider silk along its axis to cause the spider silk to undergo orientation stretching under stress. The application method is the same as in Example 1.
[0059] Step 4: While keeping the axial pre-strain constant, place the spider silk in a vacuum environment and dry it at room temperature for 2 hours to stabilize and solidify the internal orientation structure of the spider silk.
[0060] Step 5: Arrange the spider silk fibers treated in step 4 in parallel and twist them in a number different from that in Example 1, so that multiple spider silk fibers form a yarn structure, wherein the number of spider silk fibers used to construct the suture is 100-1000, thereby obtaining natural spider silk-based surgical sutures with different diameters.
[0061] The natural spider silk-based surgical sutures prepared by the above method maintain their adaptive shrinkage characteristics, while their overall diameter and mechanical load-bearing capacity change accordingly with the changes in the suture structural parameters.
[0062] Example 6: Application of natural spider silk-based adaptive surgical sutures in skin tissue suturing This embodiment provides a method for applying natural spider silk-based adaptive surgical sutures in skin tissue suturing. Figure 5 The biocompatibility evaluation of the surgical suture products of this invention includes cell compatibility and blood compatibility; Appendix Figure 6 This invention demonstrates the surgical sutures of the present invention compared to traditional nylon sutures used for skin suturing and their degradation.
[0063] Step 1: Prepare natural spider silk-based adaptive surgical sutures according to the method described in Example 1. The sutures are formed by twisting multiple spider silk fibers that have undergone humidity balancing treatment, axial pre-strain application, and vacuum drying and shaping.
[0064] Step 2: During the dermatological surgery, select an appropriate size of natural spider silk-based adaptive surgical suture according to the length and thickness of the skin wound to be sutured, and disinfect and prepare the suture according to the routine surgical procedure.
[0065] Step 3: Use the natural spider silk-based adaptive surgical suture to suture the skin wound. The wound is closed and fixed using conventional skin suturing methods, so that the suture provides the necessary mechanical support to the skin tissue in its initial state.
[0066] Step 4: After suturing, the natural spider silk-based adaptive surgical suture exhibits axial contraction behavior under the influence of wound exudate and the moist environment of skin tissue, thereby continuously applying adaptive tension to the skin wound to compensate for tension changes caused by the reduction of postoperative tissue swelling or deformation.
[0067] Through the above-described application methods, the natural spider silk-based adaptive surgical suture can continuously participate in tissue biomechanics regulation during the skin wound healing process, making it suitable for surgical suturing of skin tissue.
[0068] Example 7: Application of natural spider silk-based adaptive surgical sutures in gastric tissue suturing This embodiment provides a method for applying natural spider silk-based adaptive surgical sutures in gastric tissue suturing. Figure 7 The specific suturing method and the suturing of the surgical sutures in this invention are illustrated; Appendix Figure 8 This demonstrates the recovery process during surgery and the biodegradation of intersecting traditional nylon sutures. Step 1: Prepare natural spider silk-based adaptive surgical sutures according to the method described in Example 1. The sutures are formed by twisting multiple spider silk fibers that have undergone humidity balancing treatment, axial pre-strain application, and vacuum drying and shaping.
[0069] Step 2: During gastric surgery, select appropriate specifications of natural spider silk-based adaptive surgical sutures according to the thickness of the gastric wall tissue to be sutured and the size of the wound, and disinfect and prepare the sutures according to the routine internal organ surgery procedures.
[0070] Step 3: Use the natural spider silk-based adaptive surgical suture for suturing the gastric wall wound. The wound is closed and fixed using conventional gastric tissue suturing methods, so that the suture provides the necessary mechanical support to the gastric tissue in its initial state.
[0071] Step 4: After suturing is completed and the postoperative stage begins, the natural spider silk-based adaptive surgical suture exhibits axial contraction behavior under the influence of gastric tissue secretions and the moist physiological environment within the body, thereby applying continuous adaptive tension to the gastric wall wound to compensate for tension changes caused by tissue peristalsis and deformation.
[0072] Through the above-described application, the natural spider silk-based adaptive surgical suture can provide stable and dynamically adjustable suture tension during the healing process of gastric wounds, making it suitable for surgical suturing of gastric tissues.
[0073] In addition, those skilled in the art can make other changes based on the technical solution of this invention, such as modifications, equivalent substitutions and improvements. All changes made based on the technical solution of this invention should be included within the scope of protection of this technical solution.
Claims
1. A method for preparing a natural spider silk-based adaptive surgical suture, characterized in that, Includes the following steps: (1) The obtained natural spider silk was subjected to moisture balancing treatment under controlled humidity conditions to improve the flexibility of the protein chains; the humidity of the moisture balancing treatment was 25% to 100%, and the treatment time was 1 to 5 days. (2) Apply axial pre-strain to the spider silk after moisture balancing treatment and stretch it; the tensile strain is 10% to 80% and the stretching time is 0.5 to 6 hours; (3) Under the condition of maintaining the axial pre-strain, the spider silk is dried and annealed to allow the protein chains to rearrange in an orderly manner in the stress field, thereby obtaining spider silk fibers; the annealing temperature is from room temperature to 150 ℃, and the annealing time is 0.5 to 6 hours. (4) Arrange multiple spider silk fibers processed in step (3) in parallel according to a predetermined number and twist them to form a suture body with a yarn structure, thereby obtaining a surgical suture with adaptive shrinkage capability.
2. The preparation method according to claim 1, characterized in that, Step (1) The method for obtaining natural spider silk is to obtain continuous natural spider silk fibers by pulling them from the spider body at a constant traction speed of about 4 cm / s. The obtained spider silk is fixed on a support and stored in an environment with a temperature of 25 ℃ and a relative humidity of less than 25% to obtain an initial spider silk sample.
3. The preparation method according to claim 1, characterized in that, The moisture balance treatment in step (1) is carried out in an environment with a relative humidity of 40% to 80%.
4. The preparation method according to claim 1, characterized in that, In step (3), the annealing temperature is carried out at room temperature to 60 °C, and the length of the spider silk is limited during the drying process to maintain the axial pre-strain.
5. A natural spider silk-based adaptive surgical suture, characterized in that, The surgical suture is obtained by the preparation method according to any one of claims 1-3.
6. The natural spider silk-based adaptive surgical suture according to claim 5, characterized in that, The surgical suture is made of natural spider silk. After being treated with moisture regulation, the natural spider silk is subjected to restricted drying and shaping under axial pre-strain, which causes the protein chains inside the spider silk to rearrange in an orderly manner and form a highly oriented nanofiber structure. The surgical suture can generate axial contraction stress in a moist physiological environment, thereby achieving adaptive adjustment of the tension at the suture site.
7. The natural spider silk-based adaptive surgical suture according to claim 6, characterized in that, The nanofiber structure is composed of highly axially oriented ultrafine nanofibers inside the surgical suture, with an average diameter of less than 50 nm.
8. The natural spider silk-based adaptive surgical suture according to claim 6, characterized in that, Under the influence of moisture regulation and axial pre-strain, the spider silk exhibits an increased β-sheet structure content and a decreased α-helical structure content in its protein chains, thereby enhancing the mechanical properties and environmental responsiveness of the suture.
9. The natural spider silk-based adaptive surgical suture according to any one of claims 5-8, characterized in that, The tensile strength of the surgical suture is not less than 1.5 GPa, and the elongation at break is 50%. The axial shrinkage stress generated by the surgical suture under conditions of increased humidity is not less than 90 MPa.