Multi-layer soft tissue medical suture and preparation method thereof

Abstract

The invention relates to the technical field of medical sutures, and discloses a multi-layer soft tissue medical suture and a preparation method thereof.The multi-layer soft tissue medical suture comprises an inner layer and an outer layer, and the inner layer and the outer layer form a suture; the inner layer is made of a single-layer or multi-layer high polymer material; and the outer layer is a single-layer or multi-layer polymer elastomer. According to the multi-layer medical suture line for the soft tissue and the preparation method of the multi-layer medical suture line, the inner layer is a high-strength suture line and provides necessary strength, and the outer layer is an elastic body and has good strength and softness, tissue cutting can be reduced, and the multi-layer medical suture line can be applied to soft tissue suture.

Description

Technical Field

[0001] The invention relates to the field of medical sutures, and in particular to a multi-layer soft tissue medical suture and a preparation method thereof. Background Art

[0002] With the continuous advancement of medical technology, polymer materials are increasingly used in the field of medical devices. During the assembly and use of medical devices, polymer materials often need to be connected with parts made of other materials. Since it is difficult to fuse different materials through other effective means, suturing has become a common connection method.

[0003] Although metal materials such as stainless steel and nickel-titanium alloy have certain strength, they often cannot be closely connected with other parts due to their own characteristics, and are not suitable for some products with precise dimensions. However, wires made of polymer materials are the preferred material when connecting multiple materials because of their softness, high toughness, good strength and good biocompatibility.

[0004] Currently, commonly used polymer suture materials include polytetrafluoroethylene (PTFE), polyamide (PA), polyester (PET), polypropylene (PP) fibers, etc. PTFE is widely used in various medical devices that can come into contact with blood due to its high strength, stable chemical properties and biological inertness; however, polyamide sutures have a large tissue reaction and are prone to inflammation. Polyester products are relatively rare in medical grade materials and are often used in non-blood-contact medical devices, such as surgical sutures.

[0005] Although existing polymer sutures have many excellent properties, there are still significant problems in the application of soft tissue suturing. The strength of these sutures is much higher than that of ordinary soft tissues, especially when suturing soft tissues with extremely high mechanical properties such as beating myocardial tissue. Due to the huge difference in elastic modulus between sutures and soft tissues (PTFE suture elastic modulus is about 1.14-1.42GPa, while myocardial tissue or skeletal muscle tissue elastic modulus is only 10-20MPa), excessive stress will be generated on soft tissues during suturing, which can easily induce inflammatory reactions and seriously affect the patient's treatment effect and recovery process.

[0006] In order to solve the above problems, the present application proposes a multi-layer soft tissue medical suture and a preparation method thereof. Summary of the invention

[0007] (I) Purpose of the invention

[0008] In order to solve the technical problems existing in the background technology, the present invention proposes a multi-layer soft tissue medical suture and a preparation method thereof. The inner layer of the present invention is a high-strength suture, which provides the necessary strength, and the outer layer is an elastomer, which has better strength and softness, can reduce tissue cutting, and can be applied to soft tissue suturing.

[0009] (II) Technical solution

[0010] In order to solve the above problems, the present invention provides a multi-layer soft tissue medical suture, comprising:

[0011] An inner layer and an outer layer, wherein the inner layer and the outer layer form a suture line;

[0012] The inner layer is a single-layer or multi-layer polymer material;

[0013] The outer layer is a single-layer or multi-layer high molecular elastic body.

[0014] Preferably, the polymer material includes but is not limited to one or more of polytetrafluoroethylene PTFE, polypropylene PP, polyethylene PE, and polyethylene terephthalate PET.

[0015] Preferably, the polymer elastomer material includes but is not limited to thermoplastic polyurethane (TPU) elastomer, degradable polyurethane elastomer, degradable polylactic acid-polycaprolactone copolymer elastomer (PLCL), degradable polydioxanone (PDO), degradable polyhydroxyalkanoate (PHA) polyhydroxybutyrate (PHB) or their copolymers.

[0016] Preferably, the elastic modulus of the polymer elastomer is 5-50 MPa.

[0017] Preferably, the suture thread has a thread diameter of 0.07-1.0 mm.

[0018] Preferably, the static friction coefficient of the suture thread is 0.20-0.40.

[0019] Preferably, the dynamic friction coefficient of the suture thread is 0.10-0.35.

[0020] Preferably, the surface of the suture is coated with at least one of an anticoagulant coating, an antibacterial coating, and a hydrophilic coating.

[0021] Preferably, the suture line is a round line, a flat line or a round-flat line.

[0022] A method for preparing a multi-layer soft tissue medical suture comprises the following steps:

[0023] A single filament with a diameter of 0.07-1.0 mm is prepared by a multi-layer extrusion method; or a fiber is prepared by a dry spinning method, a wet spinning method, or a melt spinning method, and then the fiber is passed through a braiding machine to prepare a suture;

[0024] When wet spinning is used to prepare fibers, the following steps are included: dissolving thermoplastic polyurethane in a solvent to prepare a spinning solution, heating and stirring, filtering and degassing, filling the spinning solution into a micro-injection pump and pushing the needle into the needle, controlling the needle liquid outlet speed, needle diameter, and water temperature, soaking the fiber in water for a certain period of time and then drying it naturally to obtain polyurethane fiber, and then using a medical braiding machine to prepare a connecting wire with a certain number of fibers;

[0025] When a screw extruder is used to prepare fibers, at least two of the degradable polyurethane particles, PE particles, PLCL particles, PP particles, and polyurethane elastomers are poured into the screw extruder respectively, and the temperature and rotation speed are set. After becoming a melt, the spinning temperature, cooling blowing temperature, and drawing speed are set to obtain suture fibers, and then a certain number of suture fibers are formed into soft tissue medical sutures using a medical braiding machine; or the size of the die is controlled to obtain suture monofilaments.

[0026] The above technical solution of the present invention has the following beneficial technical effects:

[0027] 1. Reduce soft tissue cutting

[0028] The multi-layer structure design of the present invention provides strength protection for the inner layer, and the outer layer elastomer has a strength similar to that of soft tissue. During the suturing process, it can deform appropriately with the deformation of the soft tissue, effectively reducing the cutting of the soft tissue, reducing the incidence of inflammatory response, and promoting wound healing. It is particularly suitable for suturing soft tissues such as myocardial tissue that have high requirements for mechanical properties and are easily damaged.

[0029] (ii) Biodegradability

[0030] The outer layer is made of degradable material, which gradually degrades during the wound healing process, avoiding the risk of secondary surgery to remove sutures. At the same time, the degradation products are conducive to cell adhesion and rapid endothelialization, accelerating the tissue repair process, and improving the treatment effect and patient recovery quality.

[0031] (III) Multifunctional surface coating

[0032] The anticoagulant coating can prevent thrombosis, which is of great significance for suturing of cardiovascular and other parts, and ensures smooth blood circulation after surgery.

[0033] The antimicrobial coating inhibits bacterial growth, reduces the risk of postoperative infection, and reduces the use of antibiotics.

[0034] The hydrophilic coating improves the operating feel and biocompatibility, making surgical operations more convenient and precise, and reducing tissue irritation and damage.

[0035] (IV) Diversified Line Type Selection

[0036] We provide a variety of wire types, including round wire, flat wire, and round flat wire, to meet the needs of different surgical scenarios and doctors' operating habits, and improve surgical efficiency and suturing quality. For example, round wire is suitable for delicate operations, and flat wire or round flat wire has a good fit when suturing a large area.

[0037] (V) Accurate performance parameter control

[0038] Strictly controlled performance parameters such as elastic modulus, wire diameter, friction coefficient, etc. ensure the applicability and reliability of sutures in various soft tissue suturing scenarios, achieve performance optimization balance, meet high-precision medical operation requirements, and provide strong support for clinical applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 The present invention provides a schematic cross-sectional structure diagram of a multi-layer soft tissue medical suture.

[0040] Figure numerals: 1, inner layer; 2, outer layer. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings. It should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0042] like Figure 1 As shown, a multi-layer soft tissue medical suture proposed by the present invention comprises:

[0043] An inner layer 1 and an outer layer 2, wherein the inner layer 1 and the outer layer 2 form a suture, wherein the diameter of the suture is 0.07-1.0 mm, the static friction coefficient of the suture is 0.20-0.40, the dynamic friction coefficient of the suture is 0.10-0.35, and the surface of the suture is coated with at least one of an anticoagulant coating, an antibacterial coating, and a hydrophilic coating; the suture line shape is a round line, a flat line, or a round-flat line;

[0044] The inner layer 1 is a single-layer or multi-layer polymer material, and the polymer material includes but is not limited to one or more of polytetrafluoroethylene, polypropylene, polyethylene, and polyethylene terephthalate.

[0045] The outer layer 2 is a single-layer or multi-layer polymer elastomer, and the polymer elastomer material includes but is not limited to thermoplastic polyurethane elastomer, degradable polyurethane elastomer, degradable polylactic acid-polycaprolactone copolymer elastomer, degradable polydioxanone, degradable polyhydroxyalkanoate polyhydroxybutyrate or their copolymers, and the elastic modulus of the polymer elastomer is 5-50MPa.

[0046] A method for preparing a multi-layer soft tissue medical suture comprises the following steps:

[0047] A single filament with a diameter of 0.07-1.0 mm is prepared by a multi-layer extrusion method; or a fiber is prepared by a dry spinning method, a wet spinning method, or a melt spinning method, and then the fiber is passed through a braiding machine to prepare a suture;

[0048] When wet spinning is used to prepare fibers, the following steps are included: dissolving thermoplastic polyurethane in a solvent to prepare a spinning solution, heating and stirring, filtering and degassing, filling the spinning solution into a micro-injection pump and pushing the needle into the needle, controlling the needle liquid outlet speed, needle diameter, and water temperature, soaking the fiber in water for a certain period of time and then drying it naturally to obtain polyurethane fiber, and then using a medical braiding machine to prepare a connecting wire with a certain number of fibers;

[0049] When a screw extruder is used to prepare fibers, at least two of the degradable polyurethane particles, PE particles, PLCL particles, PP particles, and polyurethane elastomers are poured into the screw extruder respectively, and the temperature and rotation speed are set. After becoming a melt, the spinning temperature, cooling blowing temperature, and drawing speed are set to obtain suture fibers, and then a certain number of suture fibers are formed into soft tissue medical sutures using a medical braiding machine; or the size of the die is controlled to obtain suture monofilaments.

[0050] Example 1

[0051] 10g 81A was dissolved in N,N-dimethylacetamide (DMAc) to prepare a 20% (m / v) thermoplastic polyurethane spinning solution, and the polyurethane fiber was prepared by wet spinning, with a heating temperature of 60°C and a stirring rate of 140 rpm. After filtering and degassing, the spinning solution was filled into a micro-injection pump and a needle was pushed in. The needle outlet speed was 8 ml / h, the needle diameter was 25G, the water temperature was 30°C, the fiber was soaked in water for 30 minutes, and the natural drying time was 24 hours to obtain the polyurethane fiber. 8 bundles of polyurethane fibers were used to prepare thermoplastic polyurethane connecting wires using a medical braiding machine.

[0052] The above-mentioned soft tissue medical suture was tested, and the average wire diameter was 0.35 mm, the average elastic modulus was 40 MPa, the average static friction coefficient was 0.32, and the average dynamic friction coefficient was 0.27.

[0053] Example 2

[0054] The degradable polyurethane particles and PE particles are poured into the screw extruder respectively, the temperature is set to 220°C, the rotation speed is 230-300rpm / min, and they become melt after a period of time. The spinning temperature is set to 245°C, the cooling blowing temperature is 15°C, and the drawing speed is 1800m / min to obtain suture fibers with an outer layer of degradable polyurethane and an inner layer of PE. Six bundles of suture fibers are formed into soft tissue medical sutures using a medical braiding machine.

[0055] The above medical suture thread was tested, and the average thread diameter was 0.32 mm, the average elastic modulus was 330 MPa, the average static friction coefficient was 0.29, and the average dynamic friction coefficient was 0.23.

[0056] Example 3

[0057] The degradable polylactic acid-polycaprolactone (PLCL) particles, polyurethane elastomer, and polypropylene (PP) particles are poured into the screw extruder respectively, the temperature is set to 220°C, the rotation speed is 230-300rpm / min, and they become melt after time. The spinning temperature is set to 245°C, the cooling blowing temperature is 15°C, and the drawing speed is 1800m / min to obtain suture fibers with an outer layer of degradable PLCL and TPU and an inner layer of PP. 16 bundles of suture fibers are formed into soft tissue medical sutures using a medical braiding machine.

[0058] The above medical suture thread was tested, and the average thread diameter was 0.43 mm, the average elastic modulus was 300 MPa, the average static friction coefficient was 0.32, and the average dynamic friction coefficient was 0.26.

[0059] Example 4

[0060] The degradable polylactic acid-polycaprolactone (PLCL) particles, polyurethane elastomer, and polypropylene (PP) particles are poured into the screw extruder respectively, the die size is 0.5mm, the temperature is set to 220℃, the rotation speed is 230-300rpm / min, and they become melt after time. The spinning temperature is set to 245℃, the cooling blowing temperature is 15℃, and the drawing speed is 500m / min to obtain the suture monofilament with an outer layer of degradable PLCL and TPU and an inner layer of PP.

[0061] The above monofilament was tested and found to have an average wire diameter of 0.23 mm, an average elastic modulus of 430 MPa, an average static friction coefficient of 0.29, and an average dynamic friction coefficient of 0.23.

[0062] It should be understood that the above specific embodiments of the present invention are only used to illustrate or explain the principles of the present invention, and do not constitute a limitation of the present invention. Therefore, any modifications, equivalent substitutions, improvements, etc. made without departing from the spirit and scope of the present invention should be included in the protection scope of the present invention. In addition, the appended claims of the present invention are intended to cover all changes and modifications that fall within the scope and boundaries of the appended claims, or the equivalent forms of such scope and boundaries.

Claims

1. A multi-layer soft tissue medical suture, characterized in that: include: An inner layer (1) and an outer layer (2), wherein the inner layer (1) and the outer layer (2) form a suture line; The inner layer (1) is a single-layer or multi-layer polymer material; The outer layer (2) is a single-layer or multi-layer polymer elastomer.

2. A multi-layer soft tissue medical suture according to claim 1, characterized in that: The polymer material includes, but is not limited to, one or more of polytetrafluoroethylene, polypropylene, polyethylene, and polyethylene terephthalate.

3. A multi-layer soft tissue medical suture according to claim 2, characterized in that: The polymer elastomer material includes but is not limited to thermoplastic polyurethane elastomer, degradable polyurethane elastomer, degradable polylactic acid-polycaprolactone copolymer elastomer, degradable polydioxanone, degradable polyhydroxyalkanoate polyhydroxybutyrate or copolymers thereof.

4. The multi-layer soft tissue medical suture according to claim 3, characterized in that: The elastic modulus of the polymer elastomer is 5-50 MPa.

5. The multi-layer soft tissue medical suture according to claim 4, characterized in that: The thread diameter of the suture thread is 0.07-1.0 mm.

6. The multi-layer soft tissue medical suture according to claim 5, characterized in that: The static friction coefficient of the suture thread is 0.20-0.

40.

7. The multi-layer soft tissue medical suture according to claim 1, characterized in that: The dynamic friction coefficient of the suture thread is 0.10-0.

35.

8. The multi-layer soft tissue medical suture according to claim 1, characterized in that: The surface of the suture is coated with at least one of an anticoagulant coating, an antibacterial coating, and a hydrophilic coating.

9. The multi-layer soft tissue medical suture according to claim 8, characterized in that: The suture line is round, flat or round-flat.

10. A method for preparing a multi-layer soft tissue medical suture, characterized in that: The following steps are involved: A single filament with a diameter of 0.07-1.0 mm is prepared by a multi-layer extrusion method; or a fiber is prepared by a dry spinning method, a wet spinning method, or a melt spinning method, and then the fiber is passed through a braiding machine to prepare a suture; When wet spinning is used to prepare fibers, the following steps are included: dissolving thermoplastic polyurethane in a solvent to prepare a spinning solution, heating and stirring, filtering and degassing, filling the spinning solution into a micro-injection pump and pushing the needle into the needle, controlling the needle liquid outlet speed, needle diameter, and water temperature, soaking the fiber in water for a certain period of time and then drying it naturally to obtain polyurethane fiber, and then using a medical braiding machine to prepare a connecting wire with a certain number of fibers; When a screw extruder is used to prepare fibers, at least two of the degradable polyurethane particles, PE particles, PLCL particles, PP particles, and polyurethane elastomers are poured into the screw extruder respectively, and the temperature and rotation speed are set. After becoming a melt, the spinning temperature, cooling blowing temperature, and drawing speed are set to obtain suture fibers, and then a certain number of suture fibers are formed into soft tissue medical sutures using a medical braiding machine; or the size of the die is controlled to obtain suture monofilaments.

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