Self-driven curled biological interface material as well as preparation method and application thereof

Abstract

The invention relates to a self-driven curled biological interface material and a preparation method and application thereof, the material is of a tubular structure formed by a one-way weft insertion and warp knitting fabric through self-driving, weft insertion yarns in the material are high-moisture-absorption cellulose filaments, and the arrangement and the twisting direction of the weft insertion yarns are the same. The biological interface material can be used as a medical implant in the field of seamless integration of tubular tissues. The preparation method is simple, the steps are easy to operate, the prepared biological interface material has the three-dimensional bent shape and the viscoelastic characteristic and has high physical binding performance with the wet tissue surface, and the limitation that an existing biological interface material is difficult to integrate with large-surface-curvature biological tissue is overcome.

Description

Technical Field

[0001] The invention belongs to the technical field of medical implant biointerface materials, and in particular relates to a self-driven curling biointerface material and a preparation method and application thereof. Background Art

[0002] Biointerfaces involve aspects such as biomimetic membrane interfaces, protein-modified interfaces, DNA molecule-modified interfaces, and biofunctionalized nanoparticle interfaces, so the construction of biofunctionalized interfaces plays a vital role in determining the performance of medical implants. Currently, traditional biointerface materials face many challenges, including low bioactivity at the cell interface for directing cell functions, geometric and mechanical mismatch with biological tissues with three-dimensional curved shapes and viscoelastic characteristics, and unstable fixation in dynamic physiological environments, which is caused by weak physical bonding with wet tissue surfaces.

[0003] Biointerfaces with biomimetic flexible designs can effectively optimize the biointegration of medical implants, while biointerfaces with wet bioadhesive properties can be used for seamless surgical fixation, which can effectively solve the problems of damage and inflammation that are inevitable during suture and puncture. Currently, the most widely used are hydrogels with tissue viscoelasticity and excellent flexibility, which have good shape adaptability and adjustable mechanical flexibility. However, traditional hydrogel biointerfaces only show weak interfacial bonding with biological tissues, resulting in limited application in their dynamic physiological environments. Due to the poor biocompatibility of other biointerfaces due to non-natural hydrogel components, cellular responses in long-term biointegration may also be affected. Secondly, the problem of seamless integration with tubular tissues still exists. At present, in clinical use, excessive strain and high internal stress are generated in the process of manually preforming the biointerface into the target tubular shape in a passive compliant manner, which makes it difficult for the biointerface to adapt to the tubular tissue. Summary of the invention

[0004] The present invention aims to solve the above problems and provides a self-driven curling biointerface material with good biological activity and good integration with biological tissues with large surface curvature, as well as a preparation method and application thereof.

[0005] The present invention adopts the following technical scheme: a self-driven curling biointerface material, wherein the material is a unidirectional weft-inserted warp knitted fabric which is self-driven to form a tubular structure, wherein the weft-inserted yarns in the material are highly hygroscopic cellulose filaments, and the arrangement of the weft-inserted yarns is the same as the twist direction.

[0006] Furthermore, the twist of the highly hygroscopic cellulose filaments is 10 to 50 twists / 10 cm.

[0007] Furthermore, the highly hygroscopic cellulose filaments are carboxymethylated modified cellulose filaments, and the specific preparation method comprises the following steps: (1) Alkalization treatment of cellulose filaments: immersing the cellulose filaments in an alkalization treatment solution for a reaction time of 15-30 min at a reaction temperature of 40-45° C., wherein the alkalization treatment solution is a sodium hydroxide solution with a mass percentage concentration of 6-7%; (2) Etherification treatment of cellulose filaments: placing the alkalized cellulose filaments in an etherification treatment solution, wherein the etherification treatment solution is a chloroacetic acid solution with a mass percentage concentration of 6-7%, the reaction time is 90-120 minutes, and the reaction temperature is 65-70°C; (3) Post-treatment: Rinse the etherified cellulose filaments with anhydrous ethanol several times and then dry them naturally or dry them at low temperature.

[0008] A method for preparing a self-driven curling biointerface material comprises the following steps: (1) The material is a unidirectional weft-inserted warp knitted fabric structure, the ground weave is a chain weave, the chain weave uses 0.03-0.3mm polypropylene monofilament, and high-hygroscopic cellulose filament is used as the weft-inserted yarn in the weft direction. The yarn insertion method is full insertion; (2) The warp drawing process of the ground fabric is: 1-0 / 0-1 / / , the warp let-off is 3080 mm, and the warp drawing process of the weft fabric is: 0-0 / 1-1 / / , the warp let-off is 860 mm; (3) Disinfecting the above fabrics.

[0009] Furthermore, the material is woven by a warp knitting machine, which includes two combs, and the machine speed during the weaving process is 800r / min.

[0010] A self-driven curling biointerface material for medical implants with seamless integration into tubular tissues.

[0011] Self-driving principle of biointerface material: In the present invention, the highly hygroscopic cellulose filaments as weft yarns will produce anisotropic expansion after absorbing moisture, and the yarn diameter will increase. Therefore, the biointerface material will undergo self-driven untwisting, causing the material to curl as a whole, such as Figure 3 As shown in the figure, the weft yarns are closely arranged in the fabric and the filaments are intertwined with each other. When the diameter of the weft yarn increases, the length in the warp direction must increase to keep the state of wrapping around the weft yarns. However, there is no increased external force in the warp direction and the length cannot increase. Therefore, the distance between the weft yarns is gradually tightened, that is, the density of the weft yarns increases, so that the bio-interface material shrinks and winds in the radial direction. The entire bio-interface material is self-driven and wound into a tubular structure. The weft yarns after moisture absorption are in a gel state and can adhere well to biological tissues, forming an overall structure with biological tissues, thereby realizing seamless integration of biological tubular tissues.

[0012] The advantages of the present invention are specifically as follows: (1) The biointerface material prepared by the present invention is a unidirectional weft-inserted warp knitted fabric, which has good dimensional stability and a smooth surface. After using highly hygroscopic cellulose filaments as weft-inserted yarns, the fabric has good tensile strength along the direction of the weft-inserted yarns and strong curling along the direction perpendicular to the weft-inserted yarns, so that the material can be self-driven and curled into a tube, which is used for seamless integration of tubular tissues and has good shape adaptability and adjustable mechanical flexibility.

[0013] (2) In the biointerface material of the present invention, highly hygroscopic cellulose filaments are used as weft yarns for weaving. The modified cellulose filaments have good biocompatibility and hygroscopicity, high biological activity, and can be used to guide the proliferation of functional cells at the biointerface during use.

[0014] (3) The biointerface material prepared by the present invention has strong bonding with the wet tissue surface and has good three-dimensional bending shape and viscoelasticity, and can better adapt to biological tissues with large surface curvature when used. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the twisting structure of the highly hygroscopic cellulose filaments in the present invention.

[0016] Figure 2 This is a schematic diagram of the organizational structure of the unidirectional weft-inserted warp knitted fabric of the biointerface material of the present invention.

[0017] Figure 3 Schematic diagram of the curling of the biointerface material of the present invention.

[0018] Figure 4 The surface morphology SEM images of the highly hygroscopic cellulose filaments before and after modification in the present invention.

[0019] Figure 5 This is a relationship diagram between the degree of substitution under different conditions during the modification process of the highly hygroscopic cellulose filaments in the present invention.

[0020] Figure 6 This is a diagram showing the cytotoxicity test results of the biointerface material of the present invention.

[0021] Figure 7 This is a diagram of the self-driven curling process of the biointerface material in the present invention.

[0022] Figure 8 This is a real picture of the self-driven curling of the biological interface material in the present invention. DETAILED DESCRIPTION

[0023] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and understandable, the present invention is further explained and illustrated in conjunction with specific embodiments below.

[0024] Example 1: Preparation of highly hygroscopic cellulose filaments: (1) Select 600D cellulose filaments without primary twist, and use mechanical twisting method to apply rotational motion to the cellulose filaments so that the twist of the filaments is 20 twists / 10cm. Figure 1 As shown; (2) Modification treatment: The twisted cellulose filaments are carboxymethylated. The specific steps are as follows: first, the cellulose filaments are alkalized by preparing a sodium hydroxide solution with a mass percentage of 30%, and the cellulose filaments are immersed in the sodium hydroxide solution. The reaction time is 35 minutes, the reaction temperature is 45°C, and the mass ratio of cellulose filaments to sodium hydroxide is 1:5; then, the cellulose filaments after the alkalization treatment are etherified by placing the cellulose filaments in a chloroacetic acid solution for neutralization reaction. The mass percentage concentration of the chloroacetic acid solution is 6%, and the solvent is anhydrous ethanol. The reaction time is 2 hours and the reaction temperature is 70°C; finally, the cellulose filaments are rinsed with a large amount of anhydrous ethanol until there is no solution residue on the surface of the cellulose filaments. The rinsed cellulose filaments are naturally dried or placed in an oven to dry at a temperature of 55°C to obtain highly hygroscopic cellulose filaments.

[0025] The surface morphology of highly hygroscopic cellulose filaments was observed before and after modification. Figure 4 (a) is the surface morphology of cellulose filaments before modification. Figure 4 (b) is the surface morphology of the modified cellulose filaments. It can be seen from the figure that the surface roughness of the modified fibers increases. This is because the cellulose filaments are chemically modified to obtain a high-polymer fiber ether, whose structure is mainly composed of D-glucose units connected by β (1→4) glycosidic bonds. During the modification process, the cellulose filaments first undergo an alkalization reaction with NaOH. With the addition of chloroacetic acid, the hydrogen on the hydroxyl group of its glucose unit undergoes a substitution reaction with the carboxylmethyl group in chloroacetic acid, resulting in the production of carboxylmethyl groups on its glucose unit. The carboxylmethyl group is related to the hygroscopicity of the fiber. Fibers with carboxylmethyl groups have higher hygroscopicity and have a certain degree of water solubility. Figure 4 (c) is the cross-sectional morphology of the cellulose filaments before modification. Figure 4 (d) is the cross-sectional morphology of the modified cellulose filaments. It can be seen from the figure that the modified cellulose filaments not only have a rough outer surface, but also substitution reactions have occurred inside the fibers.

[0026] Since the cellulose filaments are first modified by an alkalization reaction with NaOH, and then chloroacetic acid is added, the hydrogen on the hydroxyl group on the glucose unit undergoes a substitution reaction with the carboxylmethyl group in the chloroacetic acid. There are three hydroxyl groups on each glucose unit, namely C2, C3, and C6 hydroxyl groups. The degree of substitution is expressed by the degree of substitution. If the hydrogen on the three hydroxyl groups on each unit is replaced by carboxylmethyl, it is defined as a degree of substitution of 3. The degree of substitution directly affects the solubility, viscosity, stability, acid resistance, and salt resistance of the fiber. As the degree of substitution increases, other properties are improved accordingly. When the degree of substitution is greater than 0.8, its acid resistance and salt resistance are significantly enhanced. As the degree of substitution increases, the hygroscopic solubility of the cellulose filament increases.

[0027] Figure 5 The changes of substitution degree under different modification conditions. Figure 5 (a) is the effect of sodium hydroxide concentration on substitution degree. Figure 5 (b) is the effect of chloroacetic acid concentration on substitution degree. Figure 5 (c) is the effect of etherification time on substitution degree. Figure 5 (d) is the effect of etherification temperature on the degree of substitution. The degree of substitution directly affects the hygroscopicity of the modified cellulose filaments, and thus affects the process of self-driven curling. When the degree of substitution of the modified cellulose fiber is greater than 1, it indicates that it has good hygroscopic expansion and can promote the occurrence of curling. Figure 2 It can be seen that the optimal modification conditions are: the mass percentage concentration of sodium hydroxide is 30%, the mass percentage concentration of chloroacetic acid is 6%, the etherification time is 2h, and the etherification temperature is 70℃.

[0028] Example 2: Weaving of biological interface materials The specific weaving method steps are as follows: (1) A warp knitting machine of RS2(3)MSUS type produced by KARL MAYER was used, with a machine gauge of E12, a machine width of 267 cm, a number of guide bars of 2, a machine speed of 800 r / min, and high hygroscopic cellulose filaments as weft yarns. The fabric had a unidirectional weft warp knitting structure, and the ground structure was a chain knitting structure. (2) The arrangement direction of the weft yarn is the same as the twist direction. The chain structure uses 0.08 mm polypropylene monofilament. The ground structure uses comb 1, 1-0 / 0-1 / / , the warp let-off is 3080 mm, and the weft structure uses comb 2, 0-0 / 1-1 / / , full wear, and the warp let-off is 860 mm. (3) The woven biointerface material is sterilized at high temperature at 120°C for 120 minutes. Figure 2 shown.

[0029] Example 3: Application of biointerface materials The biological interface material prepared by the present invention has good biocompatibility. The cytotoxicity test is carried out using L929 mouse fibroblasts, and the cells are cultured with the leaching solution of the biological interface material to observe the survival state of the cells after culture.

[0030] Figure 6 (a) is the result of cell live-death staining experiment. The control group is the blank group. Figure 6 (a) The survival status of L929 cells in bioactive materials, where green represents live cells and red represents dead cells. It can be seen that the number of live cells is much greater than that of dead cells. Figure 6 (b) The cell survival rates of the biointerface material group and the control group are similar, 96.07% and 96.89%, respectively. According to the current Chinese standard - Biological Evaluation of Medical Devices: GB / T 16886.5-2022, it can be seen that the biointerface material prepared by the present invention has good bio-tissue compatibility.

[0031] Figure 3 and Figure 7 This is the self-driven curling process of the biological interface. The biological interface woven from modified cellulose filaments has high hygroscopicity. The biological interface material is placed on the biological tissue that needs to be curled into a tubular structure (replaced by tubular iron wire here). The biological interface can absorb biological tissue exudate or blood (replaced by spraying water here). The highly hygroscopic cellulose filaments as weft yarns will produce anisotropic expansion after absorbing moisture, and the yarn diameter will increase. Therefore, the biological interface material undergoes self-driven untwisting, causing the material to curl as a whole, such as Figure 7 As shown in the figure, the entire biointerface material is self-driven and rolled into a tubular structure, and the weft yarn after moisture absorption is in a gel state, which can adhere well to the biological tissue and form an integral structure with the biological tissue, realizing the seamless integration of the biological tubular tissue. The actual picture after rolling is shown in the figure. Figure 8 (a) and Figure 8 (b) It is known.

Claims

1. A self-driven curling biointerface material, characterized in that: The material is a tubular structure formed by self-driving a unidirectional weft-inserted warp knitted fabric, in which the weft-inserted yarns are highly hygroscopic cellulose filaments, and the arrangement of the weft-inserted yarns is the same as the twist direction.

2. The self-driven curling biointerface material according to claim 1, characterized in that: The twist degree of the highly hygroscopic cellulose filament is 10 to 50 twists / 10 cm.

3. The self-driven curling biointerface material according to claim 1, characterized in that: The highly hygroscopic cellulose filaments are carboxymethylated modified cellulose filaments, and the specific preparation method comprises the following steps: (1) Alkalization treatment of cellulose filaments: immersing the cellulose filaments in an alkalization treatment solution for a reaction time of 15-30 minutes at a reaction temperature of 40-45° C., wherein the alkalization treatment solution is a sodium hydroxide solution with a mass percentage concentration of 25-30%; (2) Etherification treatment of cellulose filaments: placing the alkalized cellulose filaments in an etherification treatment solution, wherein the etherification treatment solution is a chloroacetic acid solution with a mass percentage concentration of 6-7%, the reaction time is 90-120 minutes, and the reaction temperature is 65-70°C; (3) Post-treatment: Rinse the etherified cellulose filaments with anhydrous ethanol several times and then dry them naturally or dry them at low temperature.

4. A method for preparing a self-driven curling biointerface material, characterized in that: The steps include: (1) The material is a unidirectional weft-inserted warp knitted fabric structure, the ground weave is a chain weave, the chain weave uses 0.03-0.3mm polypropylene monofilament, and high-hygroscopic cellulose filament is used as the weft-inserted yarn in the weft direction. The yarn insertion method is full insertion; (2) The warp drawing process of the ground fabric is: 1-0 / 0-1 / / , the warp let-off is 3080 mm, and the warp drawing process of the weft fabric is: 0-0 / 1-1 / / , the warp let-off is 860 mm; (3) Disinfecting the above fabrics.

5. The method for preparing the self-driven curling biointerface material according to claim 4, characterized in that: The material is woven by a warp knitting machine, which comprises two comb bars and has a machine speed of 800 r / min during the weaving process.

6. Application of a self-driven curling biointerface material as a medical implant in the direction of seamless integration of tubular tissues.

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