CN115990292A - Patterned polyester fiber/collagen cornea regeneration repair material for enhancing interface binding force and preparation method thereof - Google Patents
Patterned polyester fiber/collagen cornea regeneration repair material for enhancing interface binding force and preparation method thereof Download PDFInfo
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Abstract
The invention belongs to the field of cornea repair materials, and discloses a patterned polyester fiber/collagen cornea regeneration repair material for enhancing interface binding force and a preparation method thereof. The preparation method comprises the steps of preparing a patterned polyester fiber film, hydrophilic modification, optical customization and composite film forming of the patterned polyester fiber film and a collagen solution by utilizing a near-field direct-writing melting electrostatic spinning machine. According to the invention, the patterned polyester fiber film is prepared by a collecting platform controlled by a near-field direct-writing melt electrostatic spinning machine program, and is treated by an alkaline solution to become a surface hydrophilic material, so that the interface binding force with collagen is enhanced, and the prepared composite film has a stable structure. The composite film has stronger mechanical property and can resist the tearing of the conventional suture in the operation. Meanwhile, proliferation and adhesion of cornea epithelial cells can be realized, rapid epithelialization on the implant after operation is hopeful to be supported, and finally, the requirement of cornea transplantation substitutes is met.
Description
Technical Field
The invention belongs to the field of cornea repair materials, and particularly relates to a patterned polyester fiber/collagen cornea regeneration repair material for enhancing interface binding force and a preparation method thereof.
Background
The cornea is the outermost tissue of the human body, as is the skin, except that the cornea is a transparent, avascular tissue that provides two-thirds of the refraction of the eye and plays a key role in normal vision. Because the cornea is exposed to the external environment for a long period of time, the cornea is subject to mechanical, thermal, particulate dust, chemical injury, microbial infection and the like, and the resulting damage often results in corneal dysfunction, off-white opaqueness, vision loss and even blindness. At present, small lesions of the cornea are treated with antibiotics and lubricants, while mild to moderate pain can be controlled by non-steroidal anti-inflammatory drugs. Cornea transplants are often the best solution when corneal pathology results in severe and irreversible scarring. However, fresh donated cornea is in short supply, and allogeneic cornea grafts present unknown immunological rejection risks and weak mechanical properties, so development of cornea repair materials for pathological cornea tissues is very important and urgent.
Collagen, which is a main component of cornea, has excellent biocompatibility, high light transmittance, no toxicity, and low immunogenicity, and is considered as a promising material for manufacturing cornea implants. However, when collagen is extracted and purified, the internal ordered structure is destroyed, and thus the mechanical strength is lowered. One way to enhance the mechanical strength of collagen is to use chemical cross-linking agents such as genipin, cyclodextrin, etc., however, the mechanical enhancement effect is not obvious due to the low cross-linking efficiency. The other is compounding with an artificial polymer (such as PCL, PLGA, PET) with good mechanical properties. The collagen-based cornea implant with improved mechanical strength can be obtained by using the densified polyester collagen composite membrane (such as Col-PCL), but the surface of the polyester is highly hydrophobic, has weak bonding force with hydrophilic collagen, is easy to peel and delaminate in a wet environment containing water, has poor composite stability, and cannot meet the requirements of cornea implant materials.
Disclosure of Invention
In order to overcome the above-mentioned drawbacks and disadvantages of the prior art, a primary object of the present invention is to provide a patterned polyester fiber/collagen cornea regeneration repair material for enhancing interfacial bonding force.
The invention also aims to provide a preparation method of the patterned polyester fiber/collagen cornea regeneration repair material for enhancing the interfacial binding force.
It is still another object of the present invention to provide the use of the above-described patterned polyester fiber/collagen cornea regeneration repair material for enhancing interfacial bonding force in cornea repair material.
The aim of the invention is achieved by the following scheme:
a patterned polyester fiber/collagen cornea regeneration repair material for enhancing interface binding force is formed by compounding a polyester fiber film and a collagen solution, wherein the shape of the patterned polyester fiber film is square, triangular diagonal, square diagonal and the like.
The square polyester fiber film (F-polyester) is formed by stacking mutually perpendicular polyester fibers, the triangular diagonal polyester fiber film (SX-polyester) is formed by stacking mutually 60 DEG polyester fibers, the square diagonal polyester fiber film (FX-polyester) is formed by stacking two pairs of mutually perpendicular polyester fibers, and the included angle formed between the two pairs of independent mutually perpendicular polyester fibers is 45 deg.
The fiber spacing of the square, bias or square bias polyester fiber film is arbitrarily adjustable, and the fiber spacing is 100-500 mu m.
A preparation method of a patterned polyester fiber/collagen cornea regeneration repair material for enhancing interfacial binding force comprises the steps of preparing a patterned polyester fiber film, modifying the hydrophilicity of the polyester fiber film, customizing the polyester fiber film, preparing a collagen solution and compounding the polyester fiber film and collagen into a film.
The preparation method of the patterned polyester fiber/collagen cornea regeneration repair material for enhancing the interface binding force specifically comprises the following steps:
(1) Polyester particles are filled into a charging basket of a near-field direct-writing melting electrostatic spinning machine;
(2) Selecting a corresponding square wave mode or CAD mode, setting electrospinning parameters, and depositing polyester fibers into the plate glass to form a polyester fiber film;
(3) Carrying out hydrophilic modification on the polyester fiber membrane;
(4) Optically customizing a polyester fiber film;
(5) Dissolving collagen (Col) with an acid solution to obtain a collagen solution, and adding a cross-linking agent for reaction;
(6) And (3) casting and compounding the polyester fiber film and the collagen solution to form the film.
Preferably, the polyester in step (1) comprises Polycaprolactone (PCL), polylactic-co-glycolic acid (PLGA), polyethylene terephthalate (PET), etc.;
preferably, the molecular weight of the polyester in step (1) is 68000 to 80000;
preferably, in the step (2), the CAD mode is personalized drawing by Auto CAD software, and is run after the verification by the near-field direct-writing melt electrostatic spinning machine.
Preferably, in the step (2), the electrospinning parameters are voltage of 3.9-5.1 KV, receiving height of 4.0-6.0 mm, melting temperature of 75-95 ℃, platform moving speed of 20-150 mm/s, taylor cone needle of 25-35G, pushing air pressure of 20-40 KPa, fiber spacing of 100-500 μm, deposition temperature of 20-30 ℃ and humidity of 30-60%.
Preferably, the hydrophilic modification in the step (3) is to improve the hydrophilicity of the polyester fiber membrane by using an alkaline solution, wherein the alkaline solution is NaOH or Na 2 CO 3 、NaHCO 3 The concentration of the alkaline solution is 1-3 mol/L; further preferably, naOH solution having a concentration of 1 to 3mol/L is selected.
Preferably, the optical customization of the polyester fiber film in the step (4) is to make a large round hole in the center of the film, and the diameter of the hole is 3-5 mm.
Preferably, the collagen in step (5) is bovine achilles tendon type I collagen; the acid solution is hydrochloric acid (HCl), acetic acid (CH) 3 COOH), malic acid (HOOC-CHOH-CH 2 -COOH) at a concentration of 0.005 to 0.02mol/L, said collagen solution having a concentration of 5.0 to 7.0mg/ml; further preferably, HCl with a concentration of 0.005-0.02 mol/L is selected to dissolve collagen;
preferably, the cross-linking agent in step (5) is at least one of carbodiimide (EDC), N-hydroxysuccinimide (NHS), glutaraldehyde (GA); the reaction condition is that the reaction is carried out for 4 to 24 hours at the temperature of 4 to 20 ℃;
further preferably, the crosslinker in step (5) is an EDC/NHS double-mixed crosslinker according to m Col :m EDC :m NHS The EDC/NHS double-mixed cross-linking agent with the corresponding weight ratio of 6:1:1 to 4:1:1 is added, and the mixture is reacted for 4 hours at the temperature of 4 ℃;
the patterned polyester fiber/collagen cornea regeneration repair material for enhancing the interfacial binding force prepared by the method.
The patterned polyester fiber/collagen cornea regeneration repairing material for enhancing the interfacial binding force prepared by the method is applied to cornea repairing materials.
Compared with the prior art, the invention has the following advantages:
(1) The polyester fiber film prepared by the invention can be subjected to patterning design and has higher porosity.
(2) The polyester fiber membrane prepared by the invention is a hydrophilic material, has better affinity with collagen, and the obtained patterned polyester fiber/collagen cornea regeneration repair material for enhancing the interface binding force is in solution such as normal saline, deionized water, complete culture medium and the like, does not have delamination after long-term treatment, and has good composite stability.
(3) The patterned polyester fiber/collagen cornea regeneration repair material for enhancing the interface binding force has good light transmittance and excellent suture tearing resistance. Meanwhile, the composite material can realize proliferation and adhesion of cornea epithelial cells, is hopeful to support rapid epithelialization on the implant after operation, and finally meets the requirements of cornea repair and cornea transplantation substitution.
Drawings
FIG. 1 is a macroscopic morphology of the patterned PCL fiber films prepared in examples 1-3;
FIG. 2 is a graph showing the water contact angle test of the modified PCL fiber film prepared in example 4, wherein PCL-0 represents an unmodified PCL fiber film and PCL-8 represents a PCL fiber film modified for 8 hours;
FIG. 3 is a macroscopic morphology of the patterned PCL fiber/collagen cornea regeneration repair material of enhanced interfacial bonding prepared in examples 5-7;
FIG. 4 is a graph showing the transmittance test of the patterned PCL fiber/collagen cornea regeneration repair material with enhanced interfacial bonding force prepared in examples 5 to 7;
FIG. 5 is a mechanical property test of the patterned PCL fiber/collagen cornea regeneration repair material with enhanced interfacial binding force prepared in examples 5-7;
FIG. 6 is a graph showing a comparison of the stability of the patterned PCL fiber/collagen cornea regeneration repair material (FX-polyester/Col) and the densified PCL collagen composite membrane (Col-PCL) of example 7 with enhanced interfacial bonding force;
FIG. 7 is a cell proliferation graph of the patterned PCL fiber/collagen cornea regeneration repair material and pure Col membrane of example 7 enhancing interfacial binding force, wherein TCP represents an orifice plate.
Detailed Description
The present invention will be described in further detail with reference to examples and drawings, but embodiments of the present invention are not limited thereto. The specific conditions are not noted in the examples and are carried out according to conventional conditions or conditions recommended by the manufacturer. The reagents or apparatus used were conventional products commercially available without the manufacturer's attention.
The polyester is represented by PCL.
Preparation of patterned PCL fibers:
example 1
(1) Placing PCL particles into a vacuum drying oven at 40 ℃ for drying for 12 hours, and removing residual water on the surface;
(2) Placing PCL particles in the step (1) into a stainless steel charging barrel of a near-field direct-writing melt electrostatic spinning machine;
(3) Heating the PCL particles in the step (2) to 80 ℃ and preserving heat for 30min;
(4) In square wave mode, the electrospinning conditions are set: the voltage is 4.8KV, the receiving height is 4.0mm, the melting temperature is 80 ℃, the platform moving speed is 150mm/s, the Taylor conical needle is 30G, the pushing air pressure is 20KPa, the fiber spacing is 200 mu m, the deposition temperature is 25 ℃, the humidity is 50%, and the PCL melt jet pretreatment is carried out.
(5) After the PCL melt in the step (4) forms stable jet flow, starting programmed electrospinning to prepare a PCL fiber membrane (F-PCL), wherein the porosity of the PCL fiber membrane is 73.14 +/-3.35%.
(6) And (3) simply trimming the PCL film prepared in the step (5), removing redundant fiber filaments, and then placing the PCL film into a sealing bag for storage.
Example 2
(1) Placing the polyester particles into a vacuum drying oven at 40 ℃ for drying for 12 hours, and removing residual moisture on the surfaces;
(2) Placing PCL particles in the step (1) into a stainless steel charging barrel of a near-field direct-writing melt electrostatic spinning machine;
(3) Heating the PCL particles in the step (2) to 80 ℃ and preserving heat for 30min;
(4) And (3) importing triangular diagonal patterns in a CAD mode, checking and passing, and setting electrospinning conditions: the voltage is 4.8KV, the receiving height is 4.0mm, the melting temperature is 80 ℃, the platform moving speed is 150mm/s, the Taylor conical needle is 30G, the pushing air pressure is 20KPa, the fiber spacing is 200 mu m, the deposition temperature is 25 ℃, the humidity is 50%, and the PCL melt jet pretreatment is carried out.
(5) After the PCL melt in the step (4) forms stable jet flow, starting programmed electrospinning to prepare a PCL fiber membrane (SX-PCL), wherein the porosity of the obtained PCL fiber membrane is 56.20+/-1.32%.
(6) And (5) simply trimming the PCL fiber membrane obtained in the step (5), removing redundant fiber filaments, and then placing the fiber membrane into a sealing bag for storage.
Example 3
(1) Placing PCL particles into a vacuum drying oven at 40 ℃ for drying for 12 hours, and removing residual water on the surface;
(2) Placing PCL particles in the step (1) into a stainless steel charging barrel of a near-field direct-writing melt electrostatic spinning machine;
(3) Heating the PCL particles in the step (2) to 80 ℃ and preserving heat for 30min;
(4) Leading in drawn square bias patterns in a CAD mode, checking and passing, and setting electrospinning conditions: the voltage is 4.8KV, the receiving height is 4.0mm, the melting temperature is 80 ℃, the platform moving speed is 150mm/s, the Taylor conical needle is 30G, the pushing air pressure is 20KPa, the fiber spacing is 200 mu m, the deposition temperature is 25 ℃, the humidity is 50%, and the PCL melt jet pretreatment is carried out.
(5) After the PCL melt in the step (4) forms stable jet flow, starting programmed electrospinning to prepare a PCL fiber membrane (FX-PCL), wherein the porosity of the PCL fiber membrane is 46.31+/-1.14%.
(6) And (5) simply trimming the PCL fiber membrane obtained in the step (5), removing redundant fiber filaments, and then placing the fiber membrane into a sealing bag for storage.
The patterned deposition of the polyester fiber has larger influence on the mechanical property of the formed film, and the more fibers arranged in different directions on the same plane, the better the mechanical property of the formed polyester fiber film. FIG. 1 is a macroscopic view of the patterned PCL fibers of examples 1-3, showing that the F-PCL (example 1), SX-PCL (example 2) and FX-PCL (example 3) patterned PCL fibers have fiber arrangements in 2, 3 and 4 directions, respectively, and that the overlap ratio between the interlayer fibers is good, i.e., the deposition accuracy is high, demonstrating that the polyester fibers of the three patterns have been successfully prepared.
Modification of PCL fiber membrane:
example 4
(1) Weighing 0.2mol of NaOH solid to be dissolved in 100ml of deionized water to prepare 2.0mol/L NaOH solution;
(2) Immersing the PCL fiber film obtained in the example 3 into the NaOH solution obtained in the step (1), and treating for 8 hours at normal temperature and normal pressure;
(3) Washing the PCL fiber membrane treated in the step (2) by deionized water to remove the NaOH solution remained on the surface, then further removing the NaOH solution by 0.1mol/L hydrochloric acid, finally washing the hydrochloric acid by deionized water, drying at normal temperature, sealing and preserving, and testing the water contact angle to characterize the modification result.
Collagen (Col) is a hydrophilic material, while PCL fibers are a hydrophobic material. It is therefore highly desirable to surface modify the PCL fiber membrane to enhance the stability of the complex between the two. FIG. 2 is a graph showing the water contact angle test of the modified PCL fiber film of the present example after modification with NaOH solution, wherein PCL-0 is a PCL fiber film which is not treated with NaOH solution, and the PCL fiber film has a water contact angle of 119.4 degrees and is hydrophobic; PCL-8 is a PCL fiber film (PCL fiber film obtained in example 3) treated with NaOH solution for 8 hours, and has a water contact angle of 78.6-79.8 degrees, and shows hydrophilicity similar to that of the collagen surface. The principle is that NaOH solution hydrolyzes ester bonds in PCL long chains to obtain hydrophilic groups.
Preparation of patterned PCL fiber/collagen cornea regeneration repair material for enhancing interface binding force:
example 5
(1) Shearing the purified bovine achilles tendon type I collagen (Col) with scissors, dissolving with 0.01mol/L hydrochloric acid solution, and using a laboratory high-speed shearing mixer to assist shearing and dissolving under ice bath condition, wherein the rotating speed is 5000-5500 rpm;
(2) Taking 3-4 mL (parallel 3 groups) of the Col solution which is uniformly dissolved in the step (1), concentrating in a far infrared drying oven, calculating the concentration of the Col solution, and adjusting the final concentration of the Col solution to be 6.5mg/mL;
(3) Continuing stirring the Col solution obtained in the step (1) by using a mechanical stirrer, slowly adding 30mg/mL EDC/NHS crosslinking agent into the stirred Col solution in a certain amount, and reacting for 4 hours at the temperature of 4 ℃, wherein the Col: EDC: the mass ratio of NHS is 6:1:1, a step of;
(4) Slowly stirring the Col solution obtained in the step (3) at room temperature for 4-6 hours, recovering to room temperature, and centrifuging at 6000rpm for 10min at 20 ℃ to sufficiently remove bubbles in the Col solution;
(5) Pouring the Col solution obtained in the step (4) into a disposable culture dish with about 65g, inserting the F-PCL fibrous membrane prepared in the embodiment 1 into the center of the collagen solution, removing air bubbles generated in the inserting process after adjusting the position of the F-PCL fibrous membrane, and finally placing the F-PCL fibrous membrane into an ultra clean bench for air drying to obtain the patterned PCL fibrous/collagen cornea regeneration repair material (F-PCL/Col) for enhancing the interfacial binding force.
Example 6
(1) Shearing the purified bovine achilles tendon type I collagen (Col) with scissors, dissolving with 0.01mol/L hydrochloric acid solution, and using a laboratory high-speed shearing mixer to assist shearing and dissolving under ice bath condition, wherein the rotating speed is 5000-5500 rpm;
(2) Taking 3-4 mL (parallel 3 groups) of the Col solution which is uniformly dissolved in the step (1), concentrating in a far infrared drying oven, calculating the concentration of the Col solution, and adjusting the final concentration of the Col solution to be 6.2mg/mL;
(3) Continuing stirring the Col solution obtained in the step (1) by using a mechanical stirrer, slowly adding 30mg/mL EDC/NHS crosslinking agent into the stirred Col solution in a certain amount, and reacting for 4 hours at the temperature of 4 ℃, wherein the Col: EDC: the mass ratio of NHS is 6:1:1, a step of;
(4) Slowly stirring the Col solution obtained in the step (3) at room temperature for 4-6 hours, recovering to room temperature, and centrifuging at 6000rpm for 10min at 20 ℃ to sufficiently remove bubbles in the Col solution;
(5) Pouring the Col solution obtained in the step (4) into a disposable culture dish with about 62g, inserting the SX-PCL fibrous membrane prepared in the embodiment 2 into the center of the collagen solution, removing air bubbles generated in the inserting process after adjusting the position of the SX-PCL fibrous membrane, and finally placing the air bubbles into an ultra clean bench for air drying to obtain the patterned PCL fibrous/collagen cornea regeneration repair material (SX-PCL/Col) for enhancing the interface binding force.
Example 7
(1) Shearing the purified bovine achilles tendon type I collagen (Col) with scissors, dissolving with 0.01mol/L hydrochloric acid solution, and carrying out auxiliary shearing and dissolving under ice bath conditions by using a laboratory high-speed shearing mixer, wherein the rotating speed is 5000-5500 rpm;
(2) Taking 3-4 mL (parallel 3 groups) of the Col solution which is uniformly dissolved in the step (1), concentrating in a far infrared drying oven, calculating the concentration of the Col solution, and adjusting the final concentration of the Col solution to be 5.8mg/mL;
(3) Continuing stirring the Col solution obtained in the step (1) by using a mechanical stirrer, slowly adding 30mg/mL EDC/NHS crosslinking agent into the stirred Col solution in a certain amount, and reacting for 4 hours at the temperature of 4 ℃, wherein the Col: EDC: the mass ratio of NHS is 6:1:1, a step of;
(4) Slowly stirring the Col solution obtained in the step (3) at room temperature for 4-6 hours, recovering to room temperature, and centrifuging at 6000rpm for 10min at 20 ℃ to sufficiently remove bubbles in the Col solution;
(5) Pouring the Col solution obtained in the step (4) into a disposable culture dish with about 60g, cutting and inserting the FX-PCL fibrous membrane prepared in the embodiment 3 into the center of the collagen solution, removing air bubbles generated in the inserting process after adjusting the position of the FX-PCL fibrous membrane, and finally placing the culture dish into an ultra-clean bench for air drying to obtain the patterned PCL fibrous/collagen cornea regeneration repair material (FX-PCL/Col) for enhancing the interface binding force.
Fig. 3 is a macroscopic view of the patterned PCL fiber/collagen cornea regeneration repair material prepared in examples 5 to 7 in dry and wet states, in which the three patterned PCL fiber/collagen composite membranes have transparent collagen portions in the center and composite portions of the patterned PCL fiber and collagen at the periphery, and the collagen can be embedded in the pores of the PCL fiber membrane.
FIG. 4 is a graph showing the wet transmittance test of the patterned PCL fiber/collagen cornea regeneration repair material with enhanced interfacial bonding force prepared in examples 5 to 7, which has a transmittance of more than 80% and satisfies the transmittance of the natural cornea. Because collagen molecules are uniformly dispersed in the solution and can self-assemble, the whole structure of the PCL fiber is not destroyed by the PCL fiber, and the formed nano triple helix structure is transmitted by visible light.
Fig. 5 is a graph for testing the suture tensile strength of the patterned PCL fiber/collagen cornea regeneration repair material with enhanced interfacial bonding force and an in vitro pig eye suture experiment prepared in examples 5 to 7, and it is known from the graph that the F-PCL/Col film, the SX-PCL/Col film and the FX-PCL/Col film have certain differences in static tensile force, elongation at break and tensile modulus of suture tear resistance, and are remarkably improved compared with the Col film, and the FX-PCL/Col film is found to have the best mechanical properties because the fiber distribution of the FX-PCL fiber is most uniform and the PCL fiber in 4 directions is born when being subjected to tensile force, so that the mechanical improvement effect on the collagen film is most remarkable. In vitro suturing experiments of pig eyes can see that the patterned PCL fiber/collagen cornea regeneration repair material (FX-PCL/Col) for enhancing the interfacial binding force is tightly pulled by the suture, but the integrity of the material is still maintained, which shows that the problem of suture tearing resistance in the operation process is hopefully solved.
The patterned PCL fiber/collagen cornea regeneration repair material (FX-PCL/Col) with enhanced interfacial binding force prepared in example 7 has the best mechanical properties and is used for detecting stability and biological properties. FIG. 6 is a graph comparing the stability of the patterned PCL fiber/collagen cornea regeneration repair material (FX-PCL/Col) with the densified PCL collagen composite membrane of example 7, wherein the FX-PCL/Col membrane remains intact when fully immersed in deionized water, and no significant delamination of the PCL fiber membrane from the collagen is observed; whereas densification of PCL collagen composite membrane (Col-PCL) showed significant delamination. This demonstrates that the hydrophilized porous PCL fibrous membrane has a good interfacial bonding force with collagen, which is significantly better than the densified PCL collagen composite membrane (Col-PCL).
FIG. 7 is a graph showing the results of in vitro cell proliferation experiments of patterned PCL fiber/collagen cornea regeneration repair material (FX-PCL/Col) and pure Col membrane with enhanced interfacial binding force of example 7, wherein TCP represents an orifice plate as a blank group. As can be seen from the graph, the absorbance values of the patterned PCL fiber/collagen cornea regeneration repair material for enhancing the interfacial binding force and the pure Col film on the 3 rd and 5 th days are higher than those on the 1 st day and significantly different, but the proliferation effect is weaker than that of the blank group. There was no significant difference between FX-PCL/Col membranes and Col membranes. The proliferation result of the corneal epithelial cells shows that the patterned PCL fiber/collagen cornea regeneration repair material for enhancing the interfacial binding force and the pure Col membrane can realize cell proliferation and adhesion, but the effect is lower than that of the pore plate.
Comparative example
(1) Shearing the purified bovine achilles tendon type I collagen (Col) with scissors, dissolving with 0.01mol/L hydrochloric acid solution, and shearing at high speed under ice bath condition by using a laboratory high-shearing mixer, wherein the rotating speed is 5000-5500 rpm;
(2) Taking 3-4 mL (parallel 3 groups) of the Col solution which is uniformly dissolved in the step (1), concentrating in a far infrared drying oven, calculating the concentration of the Col solution, and adjusting the final concentration of the Col solution to be 6.0-7.0 mg/mL;
(3) Continuing stirring the Col solution obtained in the step (1) by using a mechanical stirrer, slowly adding 30mg/mL EDC/NHS crosslinking agent into the stirred Col solution in a certain amount, and reacting for 4 hours at the temperature of 4 ℃, wherein the Col: EDC: the mass ratio of NHS is 6:1:1, a step of;
(4) Slowly stirring the Col solution obtained in the step (3) at room temperature for 4 hours, recovering to room temperature, and centrifuging at 6000rpm for 10 minutes at 20 ℃ to sufficiently remove bubbles in the Col solution;
(5) And (3) weighing 60g of the Col solution obtained in the step (4), pouring the solution into a disposable bacterial culture dish, and then placing the dish into an ultra clean bench for air drying to obtain the Col film.
The above examples are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above examples, and any other changes, modifications, substitutions, combinations, and simplifications that do not depart from the spirit and principle of the present invention should be made in the equivalent manner, and the embodiments are included in the protection scope of the present invention.
Claims (10)
1. The patterned polyester fiber/collagen cornea regeneration repair material for enhancing the interfacial binding force is characterized by being formed by compounding a polyester fiber film and a collagen solution, wherein the shape of the patterned polyester fiber film is square, triangular diagonal or square diagonal.
2. The interfacial bonding force enhancing patterned polyester fiber/collagen cornea regeneration repair material according to claim 1, wherein: the square polyester fiber film is formed by stacking mutually perpendicular polyester fibers, the triangular diagonal polyester fiber film is formed by stacking mutually 60-degree polyester fibers, the square diagonal polyester fiber film is formed by stacking two pairs of mutually perpendicular polyester fibers, and an included angle formed between the two pairs of independent mutually perpendicular polyester fibers is 45-degree.
3. The interfacial bonding force enhancing patterned polyester fiber/collagen cornea regeneration repair material according to claim 2, wherein: the fiber spacing of the square, bias or square bias polyester fiber film is arbitrarily adjustable, and the fiber spacing is 100-500 mu m.
4. The method for preparing a patterned polyester fiber/collagen cornea regeneration repair material for enhancing interfacial bonding force according to any one of claims 1 to 3, wherein: the method comprises the steps of preparing a patterned polyester fiber film, modifying the hydrophilicity of the polyester fiber film, customizing the optics of the polyester fiber film, preparing a collagen solution and compounding the polyester fiber film and collagen into a film.
5. The method for preparing the patterned polyester fiber/collagen cornea regeneration repair material for enhancing interfacial binding force according to claim 4, which is characterized by comprising the following steps:
(1) Polyester particles are filled into a charging basket of a near-field direct-writing melting electrostatic spinning machine;
(2) Selecting a corresponding square wave mode or CAD mode, setting electrospinning parameters, and depositing polyester fibers into the plate glass to form a polyester fiber film;
(3) Carrying out hydrophilic modification on the polyester fiber membrane;
(4) Optically customizing a polyester fiber film;
(5) Dissolving collagen to obtain collagen solution, and adding a cross-linking agent for reaction;
(6) And (3) casting and compounding the polyester fiber film and the collagen solution to form the film.
6. The method for preparing the patterned polyester fiber/collagen cornea regeneration repair material for enhancing interfacial binding force according to claim 4, wherein the method comprises the following steps: the polyester in the step (1) is at least one of polycaprolactone, polylactic acid-glycolic acid copolymer and polyethylene terephthalate;
the molecular weight of the polyester in the step (1) is 68000-80000.
7. The method for preparing the patterned polyester fiber/collagen cornea regeneration repair material for enhancing interfacial binding force according to claim 4, wherein the method comprises the following steps: in the step (2), the CAD mode is drawn in a personalized way by means of Auto CAD software, and is operated after the verification of a near-field direct-writing melting electrostatic spinning machine is passed;
the electrospinning parameters in the step (2) are voltage of 3.9-5.1 KV, receiving height of 4.0-6.0 mm, melting temperature of 75-95 ℃, platform moving speed of 20-150 mm/s, taylor cone needle of 25-35G, pushing air pressure of 20-40 KPa, fiber spacing of 100-500 μm, deposition temperature of 20-30 ℃ and humidity of 30-60%.
8. The method for preparing the patterned polyester fiber/collagen cornea regeneration repair material for enhancing interfacial binding force according to claim 4, wherein the method comprises the following steps: the hydrophilic modification in the step (3) is to improve the hydrophilicity of the polyester fiber membrane by using alkaline solution, wherein the alkaline solution is NaOH or Na 2 CO 3 、NaHCO 3 One of the following; the concentration of the alkaline solution is 1-3 mol/L;
and (3) optically customizing the polyester fiber membrane in the step (4) by making a large round hole in the center of the membrane, wherein the diameter of the hole is 3-5 mm.
9. The method for preparing the patterned polyester fiber/collagen cornea regeneration repair material for enhancing interfacial binding force according to claim 4, wherein the method comprises the following steps: the collagen in the step (5) is bovine achilles tendon type I collagen; dissolving collagen with acid solution of HCl and CH to obtain collagen solution 3 COOH、HOOC-CHOH-CH 2 -at least one of COOH at a concentration of 0.005-0.02 mol/L, said collagen solution at a concentration of 5.0-7.0 mg/ml;
the cross-linking agent in the step (5) is at least one of EDC, NHS, GA; the reaction condition is that the reaction is carried out for 4 to 24 hours at the temperature of 4 to 20 ℃;
preferably, the crosslinker in step (5) is an EDC/NHS double-mixed crosslinker according to m Col :m EDC :m NHS The corresponding amount of EDC/NHS double-mixed cross-linking agent is added in a mass ratio of=6:1:1 to 4:1:1, and the reaction is carried out for 4 hours at 4 ℃.
10. Use of the patterned polyester fiber/collagen cornea regeneration repair material for enhancing interfacial bonding force according to any one of claims 1 to 3 in cornea repair material.
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