Tubular fiber-reinforced biological composite artificial blood vessel stent with degradable metamaterial structure

Abstract

The invention discloses a tubular fiber-reinforced biological composite artificial blood vessel stent with a degradable metamaterial structure. A reinforcing phase of the biological composite material artificial blood vessel stent is a tubular fiber network stent, and a matrix phase is hydrogel; the tube wall of the tubular fiber network stent is of a negative Poisson's ratio structure, and the negative Poisson's ratio structure is constructed by a fiber network formed by mutually crossing fibers; the mechanical property of the biological composite material is changed by regulating and controlling the structural parameters of the tubular fiber network stent, so that the strength of the natural blood vessel is matched with the compliance mechanical property. The problems that in the prior art, the mechanical property of a small-caliber artificial blood vessel is not matched with that of a natural artery, the compliance is insufficient, and precise regulation and control of the mechanical property are difficult to achieve are solved.

Description

Biodegradable metamaterial structure tubular fiber-reinforced biocomposite artificial vascular stent Technical Field

[0001] This invention belongs to the field of medical device technology, specifically relating to a biodegradable metamaterial structure tubular fiber-reinforced biocomposite artificial vascular stent. Background Technology

[0002] Cardiovascular disease is a major threat to human health worldwide, with persistently high morbidity and mortality rates. Vascular transplantation is a primary treatment for related diseases. Although autologous vascular transplantation is the "gold standard," its availability is limited, and it can cause damage to the donor site, making it unsuitable for nearly one-third of patients. Therefore, the demand for artificial blood vessels is enormous. Currently, large and medium-diameter (>6 mm) artificial blood vessels have achieved clinical success, but small-diameter (<6 mm) artificial blood vessels are prone to thrombosis after transplantation and have low long-term patency rates, severely limiting their application in hemodialysis, coronary artery bypass grafting, and other scenarios. One of the core bottlenecks is that traditional artificial blood vessels struggle to meet the required mechanical strength for implantation while simultaneously achieving compliance with natural arteries.

[0003] The mechanical properties of natural arteries stem from their ingenious biomimetic structure, primarily exhibiting a typical J-shaped stress-strain curve. They possess both high compliance and high strength, which is crucial for maintaining vascular function. Currently, mainstream artificial vascular materials (such as ePTFE) exhibit relatively rigid mechanical properties and insufficient compliance. While vascular scaffolds fabricated using electrospinning technology can mimic the topology of the extracellular matrix, their disordered fiber stacking and small pore size limit cell infiltration and tissue regeneration, and make precise control of the scaffold's macroscopic mechanical behavior difficult.

[0004] On the other hand, hydrogels (such as methacrylamide gelatin, GelMA) are considered ideal tissue engineering materials due to their excellent biocompatibility and ability to mimic the environment of the extracellular matrix. However, the mechanical strength of pure hydrogels is typically only in the thousands of Pascals, making it difficult to withstand the pulsating pressure of blood vessels. Existing reinforcement methods (such as constructing dual networks and adding nanomaterials) can improve strength, but they often lead to a reduction in hydrogel pore size and bioactivity, and it is difficult to achieve precise and flexible control over mechanical properties (especially compliance). Summary of the Invention

[0005] The purpose of this invention is to provide a biodegradable metamaterial structured tubular fiber-reinforced biocomposite artificial vascular scaffold. This invention solves the problems of mismatch between the mechanical properties of small-diameter artificial vascular scaffolds and natural arteries, insufficient compliance, difficulty in achieving precise control of mechanical properties, and poor biocompatibility in existing technologies.

[0006] The technical solution of this invention is as follows: a biodegradable metamaterial structure tubular fiber-reinforced biocomposite artificial vascular scaffold, wherein the reinforcing phase of the biocomposite artificial vascular scaffold is a tubular fiber network scaffold, and the matrix phase is hydrogel; the tubular fiber network scaffold has a negative Poisson's ratio structure, which is constructed by a fiber network formed by intersecting fibers; by adjusting the structural parameters of the tubular fiber network scaffold to change the mechanical properties of the biocomposite material, the matching of the strength and compliance mechanical properties of natural blood vessels can be achieved.

[0007] In the aforementioned biodegradable metamaterial structure tubular fiber reinforced biocomposite artificial vascular stent, the tubular fiber network stent based on the negative Poisson's ratio structure exhibits a negative Poisson's ratio characteristic of synchronous lateral expansion when stretched axially.

[0008] In the aforementioned biodegradable metamaterial structure tubular fiber-reinforced biocomposite artificial blood vessel stent, the fiber material for constructing the negative Poisson's ratio structure is polylactic acid, polycaprolactone, lactide-caprolactone copolymer, polydioxanone, lactide-glycolic acid copolymer, polyurethane, or any combination of two or more thereof.

[0009] In the aforementioned biodegradable metamaterial structured tubular fiber-reinforced biocomposite artificial blood vessel scaffold, the fiber network is a tubular periodic spatial network formed by multiple repeating structural units extending axially and circumferentially. Each structural unit is a cross-shaped vortex grid or a nested annular grid formed by connecting axial segments of two adjacent axially shaped fiber rings with circumferential segments of two adjacent axially shaped fiber rings. In the cross-shaped vortex grid: the starting point of both axial segments is 0P, and the ending point is 1P; the starting point of both circumferential segments is also 0P, and the ending point is also 1P; the starting point of the first axial segment and the first circumferential segment coincide; the ending point of the first axial segment and the starting point of the second circumferential segment coincide; the starting point of the second axial segment and the ending point of the first circumferential segment coincide; the ending point of the second axial segment and the ending point of the second circumferential segment coincide. In the nested annular grid: the starting points of the first axial segment and the first circumferential segment are... P, the endpoint is P; The starting points of the second axial segment and the second circumferential segment are both P, the endpoint is... P; First axial segment, first circumferential segment P is a common point, the first axial segment and the second circumferential segment have a common point, the second axial segment and the first circumferential segment have a common point, the second axial segment and the second circumferential segment have a common point. P is a common point; where P represents the waveform period.

[0010] In the aforementioned biodegradable metamaterial structure tubular fiber-reinforced biocomposite artificial blood vessel scaffold, the structural parameters of the tubular fiber network scaffold that are regulated include: the waveform period, waveform amplitude, and fiber diameter of the axial waveform fibers and waveform fiber rings; the fiber diameter of the axial waveform fibers and waveform fiber rings is 300 nm to 150 μm.

[0011] In the aforementioned biodegradable metamaterial structure tubular fiber-reinforced biocomposite artificial blood vessel stent, the axial wave fibers and the wave rings have both arc-shaped or zigzag-shaped structures at their peaks and troughs.

[0012] In the aforementioned biodegradable metamaterial structure tubular fiber-reinforced biocomposite artificial blood vessel scaffold, the tubular fiber network scaffold is fabricated based on melt near-field direct writing.

[0013] In the aforementioned biodegradable metamaterial structure tubular fiber-reinforced biocomposite artificial vascular stent, the tubular fiber network stent is surface-activated by plasma treatment / alkaline etching process, and then drugs or bioactive substances are anchored on the stent surface through dip coating or spray coating process to realize the preparation of functional stent for the treatment of vascular diseases or the promotion of vascular regeneration.

[0014] In the aforementioned biodegradable metamaterial structure tubular fiber-reinforced biocomposite artificial vascular scaffold, the elastic modulus of the hydrogel is lower than that of the tubular fiber network scaffold; the hydrogel is a highly biocompatible gelatin-based hydrogel, selected from synthetic polymers, natural polymers, or combinations thereof.

[0015] In the aforementioned biodegradable metamaterial structure tubular fiber-reinforced biocomposite artificial blood vessel stent, the hydrogel can serve as a carrier for loading drugs or bioactive substances, controlling the release of drugs or bioactive substances for the treatment of vascular diseases or the promotion of angiogenesis.

[0016] Beneficial effects: Compared with existing technologies, the tubular fiber network scaffold with a negative Poisson's ratio structure of this invention can increase biaxial tensile capacity and reduce stress concentration, exhibiting radial expansion under axial tension. Simultaneously, its mechanical properties display a J-shaped stress-strain response, highly matching the mechanical response of natural blood vessels. This makes the artificial vascular scaffold of this invention significantly advantageous in small-diameter artificial blood vessels (diameter < 6 mm), achieving compliance with natural arteries while meeting the required mechanical strength for implantation, thereby reducing thrombus formation and improving post-implantation patency.

[0017] This invention, through research, has discovered that by designing the structural parameters constituting the negative Poisson's ratio structure—waveform dimensions (period, amplitude) and / or fiber diameter—small-diameter artificial blood vessels with controllable axial modulus, burst strength, and compliance can be designed as needed. This provides a new technical approach for constructing biomimetic blood vessels that can simulate the mechanical properties of natural arteries. Through extensive experimental exploration and analysis, the small-diameter artificial blood vessel of this invention can simulate the J-shaped stress-strain curve of a natural artery, possessing excellent mechanical strength, compliance, and stability. This provides a new solution for small-diameter vascular regeneration. By adjusting the waveform dimensions and / or fiber diameter parameters, the axial modulus of the small-diameter artificial blood vessel can be adjusted within the range of 0.005 MPa to 0.50 MPa, the burst strength within the range of 60 mmHg to 5000 mmHg, and the compliance within the range of 2% to 13.28%, thereby matching the mechanical properties of natural arteries in different parts of the human body. Furthermore, the fiber material of this invention is biodegradable, inducing the regeneration of natural blood vessels during stent degradation.

[0018] In this invention, the elastic modulus of the hydrogel is lower than that of the tubular fiber network scaffold. This structure allows the axial expansion of the tubular fiber network scaffold to resist the axial contraction of the hydrogel, thereby promoting a negative Poisson's ratio effect in the entire vascular scaffold. Ultimately, this results in a vascular scaffold possessing excellent mechanical strength, compliance, and stability. In summary, this invention offers the following advantages: 1. The small-diameter artificial blood vessel of this invention, through the design of a negative Poisson's ratio structure in the reinforced tubular fiber network scaffold, reproduces the J-shaped stress-strain characteristics of a natural artery, achieving a balance between compliance and strength requirements.

[0019] 2. The small-diameter artificial blood vessel of the present invention, by precisely controlling the structural parameters of the tubular fiber network scaffold: waveform size (period, amplitude) and / or fiber diameter, can achieve adjustable axial modulus, burst pressure and compliance over a wide range, and can match the mechanical properties of arteries in different parts of the human body.

[0020] 3. The small-diameter artificial blood vessel of the present invention adopts a composite structure of tubular fiber network scaffold and hydrogel matrix, which has both mechanical strength and biological functionality. The hydrogel matrix can simulate the extracellular matrix, providing a good growth microenvironment for cells, which is conducive to the regeneration and reconstruction of vascular tissue.

[0021] 4. This invention has excellent structural stability and fatigue resistance, and has the potential for long-term implantation.

[0022] 5. The tubular fiber network scaffold of the present invention has a simple structure, consisting only of axial wave-shaped fibers and wave-shaped fiber rings. It has good performance stability and reproducibility, and its performance is easy to control. Moreover, the entire scaffold can be prepared by melt near-field direct writing technology. The entire preparation process has high controllability and repeatability, making it suitable for large-scale production and providing reliable technical support for the clinical application of small-diameter artificial blood vessels. Attached Figure Description

[0023] Figure 1 is a schematic diagram of the tubular fiber network scaffold structure; Figure 2 shows the design parameters of the negative Poisson's ratio structure; Figure 3 is a three-dimensional model of the tubular fiber network scaffold; Figure 4 shows the morphological characterization of the tubular fiber network scaffold; Figure 5 shows various actual images of tubular fiber network scaffolds; Figure 6 shows a hydrogel casting mold; Figure 7 shows an actual image of an artificial blood vessel; Figure 8 shows a compliance testing device; Figure 9 shows a periodic spatial network composed of a cross-shaped vortex mesh; Figure 10 shows a periodic spatial network composed of a ring-shaped nested mesh; Figure 11 shows a schematic diagram of the position of each major node of the fiber waveform within two periods P; Figure 12 is a schematic diagram of a cross-shaped vortex mesh; Figure 13 is a schematic diagram of a ring-shaped nested mesh. Detailed Implementation

[0024] The present invention will be further described below with reference to the accompanying drawings and embodiments, but this should not be construed as limiting the present invention.

[0025] Example 1. A biodegradable metamaterial structure with tubular fiber-reinforced biocomposite artificial vascular scaffold, as shown in Figures 1-13: The reinforcing phase of this biocomposite artificial vascular scaffold is a tubular fiber network scaffold, and the matrix phase is hydrogel; the wall of the tubular fiber network scaffold has a negative Poisson's ratio structure, which is constructed by a fiber network formed by intersecting fibers; by adjusting the structural parameters of the tubular fiber network scaffold to change the mechanical properties of the biocomposite material, the matching of the strength and compliance mechanical properties of natural blood vessels can be achieved.

[0026] Based on a tubular fiber network scaffold with a negative Poisson's ratio structure, this enhanced biocomposite artificial vascular scaffold exhibits a negative Poisson's ratio characteristic of synchronous lateral expansion when stretched axially.

[0027] The fiber materials used to construct the negative Poisson's ratio structure are polylactic acid, polycaprolactone, lactide-caprolactone copolymer, polydioxanone, lactide-glycolic acid copolymer, polyurethane, etc., or any combination of two or more thereof.

[0028] The fiber network is a tubular, periodic spatial network formed by multiple repeating structural units extending axially and circumferentially. The structural unit is a cross-shaped spiral grid (see Figures 9, 11, 12) or a nested annular grid (see Figures 10, 11, 13) formed by connecting axial segments of two adjacent axially shaped fiber rings 1 with circumferential segments of two adjacent axially shaped fiber rings 2. In the cross-shaped spiral grid: the starting point of both axial segments is 0P, and the ending point is 1P; the starting point of both circumferential segments is also 0P, and the ending point is also 1P; the starting point of the first axial segment 3 and the first circumferential segment 4 coincide; the ending point of the first axial segment 3 coincides with the starting point of the second circumferential segment 5; the starting point of the second axial segment 6 coincides with the ending point of the first circumferential segment 4; and the ending point of the second axial segment 6 coincides with the ending point of the second circumferential segment 5. In the nested annular grid: the starting points of the first axial segment 3 and the first circumferential segment 4 are... P, the endpoint is P; The starting points of the second axial segment 6 and the second circumferential segment 5 are both P, the endpoint is... P; First axial segment 3, first circumferential segment 4 P is a common point; 1P is a common point for the first axial segment 3 and the second circumferential segment 5; 1P is a common point for the second axial segment 6 and the first circumferential segment 4; 1P is a common point for the second axial segment 6 and the second circumferential segment 5. P is a common point; where P represents the waveform period.

[0029] The structural parameters of the tubular fiber network scaffold that can be controlled include: the waveform period, waveform amplitude, and fiber diameter of the axial waveform fiber 1 and the waveform fiber ring 2; the fiber diameter of the axial waveform fiber 1 and the waveform fiber ring 2 is 300nm to 150μm.

[0030] The crests and troughs of the axial wave fiber 1 and the wave fiber ring 2 are both circular arc structures or broken line structures.

[0031] The tubular fiber network scaffold was fabricated based on melt near-field direct writing.

[0032] After surface activation by plasma treatment / alkaline etching, tubular fiber network scaffolds are used to anchor drugs or bioactive substances onto the scaffold surface through dip coating or spray coating processes, thereby realizing the preparation of functional scaffolds for the treatment of vascular diseases or the promotion of angiogenesis.

[0033] The elastic modulus of the hydrogel is lower than that of the tubular fiber network scaffold; the hydrogel is a highly biocompatible gelatin-based hydrogel, selected from synthetic polymers, natural polymers, or combinations thereof.

[0034] Hydrogels can serve as carriers for loading drugs or bioactive substances, enabling controlled release of these substances for the treatment of vascular diseases or the promotion of angiogenesis.

[0035] Taking a tubular fiber network stent with both peaks and troughs in an arc structure as an example, the waveform period and amplitude can be adjusted by regulating the radius r and arc θ of the arc structure. Combined with the fiber diameter d, the structural parameters can be controlled, thereby achieving the precise design of a negative Poisson's ratio structure. This enables the active control and matching of key mechanical properties such as axial modulus, burst strength, and compliance, thus solving the problem of mismatch between the mechanical properties of existing small-diameter artificial blood vessels and natural arteries.

[0036] Taking a tubular fiber network scaffold with arc-shaped peaks and troughs as an example, the preparation method of the artificial blood vessel of the present invention is as follows: 1. A tubular fiber network scaffold with a negative Poisson's ratio structure is prepared by melt near-field direct writing technology; 2. The surface of the tubular fiber network scaffold is pretreated; 3. The pretreated tubular fiber network scaffold is placed in a mold and a hydrogel precursor solution containing a photoinitiator is injected; 4. The hydrogel precursor solution is cross-linked and cured by ultraviolet light irradiation to form a biodegradable metamaterial structure tubular fiber-reinforced biocomposite artificial blood vessel scaffold.

[0037] To verify the technical effect of the present invention, the following experiments were conducted: Experiment 1: Preparation of artificial blood vessels with negative Poisson ratios of different fiber arc radii r 1) Material preparation: Tubular fiber network scaffold materials: PCL (polycaprolactone, molecular weight 68000, melting point 60-65℃), hydrogel matrix GelMA30 (methacrylated gelatin, grafting rate 30%), LAP (lithium phenyl (2,4,6-trimethylbenzoyl)phosphate).

[0038] 2) Structural Design: Four sets of negative Poisson's ratio tubular scaffolds with different fiber arc radii were designed. The structural parameters are as follows: fiber curvature 180°, fiber diameter 55 μm, and fiber arc (circular arc structure) radius r are 0.15 mm, 0.25 mm, 0.35 mm, and 0.45 mm, respectively, with corresponding codes as follows: , , , .

[0039] 3) Preparation of negative Poisson's ratio tubular fiber network scaffold: Using a fused near-field direct writing device, PCL particles were loaded into a 10 mL barrel, equipped with a 0.20 mm stainless steel needle. The barrel temperature and needle temperature were set to 90 ℃, the air pressure was adjusted to 400 kPa, the voltage to 4.5 kV, and the distance between the needle and the mandrel (5 mm in diameter) was about 1-2 mm. The printing path was written according to the negative Poisson's ratio structure of different fiber arcs. The device was started, and a tubular scaffold with a wall thickness of 800±50 μm was printed on the mandrel at 1250 mm / min.

[0040] 4) Surface treatment: Immerse the bracket in 12% NaOH solution, treat at 25℃ for 6 hours, rinse with deionized water 5 times, and dry the surface with absorbent paper.

[0041] 5) Hydrogel composite: The treated scaffold is placed in a polytetrafluoroethylene mold, and a 10% GelMA30 hydrogel solution containing 0.5% LAP is injected. It is then cured with 405 nm ultraviolet light for 1 min.

[0042] 6) Demolding: Remove the prepared sample from the mold to obtain the negative Poisson's ratio tubular scaffolds with different fiber arc radii.

[0043] Experimental Example 2: Preparation of Negative Poisson's Ratio Artificial Blood Vessels with Different Fiber Diameters (Preparation of materials: Same as Example 12) Structural Design: Four sets of negative Poisson's ratio tubular stents with different fiber diameters were designed. The structural parameters are as follows: fiber curvature 180°, fiber arc radius 0.25 mm, and fiber diameters of 25 μm, 40 μm, 55 μm, and 70 μm, respectively, with corresponding codes as follows: , , , .

[0044] 3) Preparation of negative Poisson's ratio tubular fiber network scaffold: Using a fused near-field direct writing device, PCL particles were loaded into a 10 mL barrel, equipped with a 0.20 mm stainless steel needle. The barrel temperature and needle temperature were set to 90 ℃, the air pressure was adjusted to 260 kPa~500 kPa, the voltage to 4.5 kV, and the distance between the needle and the mandrel (5 mm in diameter) was about 1-2 mm. The printing path was written according to the negative Poisson's ratio structure of different fiber arcs. The device was started, and a tubular scaffold with a wall thickness of 800±50 μm was printed on the mandrel at 800 mm / min.

[0045] 4) Other preparation steps are the same as in Experiment 1.

[0046] Negative Poisson's ratio artificial blood vessel compliance test: The apparatus for compliance testing is shown in Figure 8.

[0047] The composite tubular support is fixed to a support with uniform water delivery pipes at both ends, and the flow rate of the fluid in the sample is controlled by a peristaltic pump. Then, a pressure sensor is used to detect the pressure inside the sample.

[0048] Real-time measurement of sample outer diameter changes. Physiological saline was selected as the fluid to simulate the human body environment. Based on the normal human blood pressure range (80 mmHg~120 mmHg), the compliance of the composite tubular stent was tested within this pressure range.

[0049] Experimental Results: The negative Poisson's ratio small-diameter artificial blood vessels prepared in the above experimental examples were subjected to radial tensile tests, burst strength tests, and compliance tests and comparisons. The tests were conducted according to the test methods in "YY / T 0500-2021 Standard for Cardiovascular Implants, Vascular Prostheses, Tubular Vessel Grafts and Vascular Patches". The test results are shown in Table 1.

[0050] Table 1. Test Items Example 1 Example 2 Radial Tensile Strength (kPa) 124~350 105~295 Bursting Strength (mmHg) 1230~325 21 180~3050 Vascular Compliance (% / 100mmHg) 6.25~13.28 6.57~12.04 surface

Claims

1. A biodegradable metamaterial structure tubular fiber-reinforced biocomposite artificial vascular scaffold, characterized in that, The reinforcing phase of this biocomposite artificial vascular scaffold is a tubular fiber network scaffold, and the matrix phase is hydrogel. The wall of the tubular fiber network scaffold has a negative Poisson's ratio structure, which is constructed by a fiber network formed by intersecting fibers. By adjusting the structural parameters of the tubular fiber network scaffold, the mechanical properties of the biocomposite material can be changed, thereby achieving a match between the strength and compliance mechanical properties of natural blood vessels.

2. The biodegradable metamaterial structure tubular fiber-reinforced biocomposite artificial vascular scaffold according to claim 1, characterized in that, Based on a tubular fiber network scaffold with a negative Poisson's ratio structure, this enhanced biocomposite artificial vascular scaffold exhibits a negative Poisson's ratio characteristic of synchronous lateral expansion when stretched axially.

3. The biodegradable metamaterial structure tubular fiber-reinforced biocomposite artificial vascular scaffold according to claim 1, characterized in that, The fiber materials used to construct the negative Poisson's ratio structure are polylactic acid, polycaprolactone, lactide-caprolactone copolymer, polydioxanone, lactide-glycolic acid copolymer, polyurethane, etc., or any combination of two or more thereof.

4. The biodegradable metamaterial structure tubular fiber-reinforced biocomposite artificial vascular scaffold according to claim 1, characterized in that, The fiber network is a tubular periodic spatial network formed by multiple repeating structural units extending axially and circumferentially; the structural unit is a cross-vortex grid or a ring-shaped nested grid formed by connecting axial segments of two adjacent axial waveform fibers (1) with circumferential segments of two adjacent waveform fiber rings (2); in the cross-vortex grid: the starting point of both axial segments is 0P and the ending point is 1P; the starting point of both circumferential segments is also 0P and the ending point is also 1P; the starting point of the first axial segment (3) and the first circumferential segment (4) are the same point, the ending point of the first axial segment (3) and the starting point of the second circumferential segment (5) are the same point, the starting point of the second axial segment (6) and the ending point of the first circumferential segment (4) are the same point, and the ending point of the second axial segment (6) and the ending point of the second circumferential segment (5) are the same point; in the ring-shaped nested grid: the starting point of the first axial segment (3) and the first circumferential segment (4) are both P, the endpoint is P; The starting points of the second axial segment (6) and the second circumferential segment (5) are both P, the endpoint is... P; First axial segment (3), first circumferential segment (4) P is a common point, the first axial segment (3) and the second circumferential segment (5) are 1P common points, the second axial segment (6) and the first circumferential segment (4) are 1P common points, the second axial segment (6) and the second circumferential segment (5) are 1P common points. P is a common point; where P represents the waveform period.

5. The biodegradable metamaterial structure tubular fiber-reinforced biocomposite artificial vascular scaffold according to claim 4, characterized in that, The structural parameters of the tubular fiber network scaffold include: the waveform period, waveform amplitude, and fiber diameter of the axial waveform fiber (1) and waveform fiber ring (2); the fiber diameter of the axial waveform fiber (1) and waveform fiber ring (2) is 300nm~150μm.

6. The biodegradable metamaterial structure tubular fiber-reinforced biocomposite artificial vascular scaffold according to claim 4, characterized in that, The crests and troughs of the axial wave fiber (1) and the wave fiber ring (2) are both circular arc structures or broken line structures.

7. The biodegradable metamaterial structure tubular fiber-reinforced biocomposite artificial vascular scaffold according to claim 1, characterized in that, The tubular fiber network scaffold was fabricated based on melt near-field direct writing.

8. The biodegradable metamaterial structure tubular fiber-reinforced biocomposite artificial vascular scaffold according to claim 1, characterized in that, After surface activation by plasma treatment / alkaline etching, tubular fiber network scaffolds are prepared by dipping or spraying to anchor drugs or bioactive substances onto the scaffold surface, thus obtaining functionalized scaffolds.

9. The biodegradable metamaterial structure tubular fiber-reinforced biocomposite artificial vascular scaffold according to claim 1, characterized in that, The elastic modulus of the hydrogel is lower than that of the tubular fiber network scaffold; the hydrogel is a highly biocompatible gelatin-based hydrogel, selected from synthetic polymers, natural polymers, or combinations thereof.

10. The biodegradable metamaterial structure tubular fiber-reinforced biocomposite artificial vascular scaffold according to claim 1, characterized in that, Hydrogels can serve as carriers for loading drugs or bioactive substances, enabling controlled release of drugs or bioactive substances.

Images