CN1172036C

CN1172036C - Fiber for tissue engineering scaffold and preparation method thereof

Info

Publication number: CN1172036C
Application number: CNB021127964A
Authority: CN
Inventors: 左葆齐; 吴徵宇; 李明忠; 戴礼兴; 朱美男
Original assignee: Suzhou University
Current assignee: Suzhou University
Priority date: 2002-03-21
Filing date: 2002-03-21
Publication date: 2004-10-20
Anticipated expiration: 2022-03-21
Also published as: CN1372023A

Abstract

The present invention relates to fiber for tissue engineering scaffolds and a preparation method thereof, which belongs to the technical field of biomedical engineering materials. The present invention uses natural cocoon fiber has major raw materials, a silk fibroin solution is obtained after degumming, dissolving and purifying, a wet spinning method is adopted, and the crystallinity is controlled to be lower than 40% to be woven into the biodegradable fiber for the tissue engineering scaffolds. Because of the physical properties such as no poison, no harm, high biocompatibility, water insolubility, certain brute force, extension, elasticity, etc., the present invention can be used as surgical repairing materials or tissue engineering scaffold materials of artificial skin, muscle tendon, cartilage, dura mater, etc.

Description

A kind of fibre for tissue engineering scaffold and preparation method thereof

Technical field

The present invention relates to the bio-medical engineering material field, particularly a kind of fibre for tissue engineering scaffold and preparation method thereof.

Background technology

Silk is made up of about 75% fibroin and 25% silk gum, it is quite pure natural protein fiber, to the human body avirulence, have no stimulation, the amino acid of fibroin is formed with human collagen albumen certain similitude, having excellent biological compatibility, is the comparatively ideal raw material of preparation bio-medical goods.But prove after deliberation, because natural silk degree of crystallinity is higher, adhesion such as big intramolecule hydrogen bond of silk is stronger in the crystal region, space structure is tight, therefore, general silk product is difficult to by biodegradation, and this just makes the application of natural fibroin at biomedical sector, especially be used as the application of tissue engineering material, be greatly limited.

Before the present invention makes, the technology of more employing is as the used in tissue engineering support with artificial materials such as PLAs in the world, pile up owing to easily produce local acidic materials in these material degradation in vivo processes, be unfavorable for adhering to, divide, breeding of cell, and cost an arm and a leg.At home, publication number is in the patent of invention " a kind of Wound surface protection film and preparation method thereof " of CN 1059129 C, and disclosing a kind of is raw material with silk, through come unstuck, after the operation such as dissolving, the method for drying and forming-film; Publication number is in the patent of invention " a kind of porous fibroin membrane and preparation method thereof " of CN1260363A, a kind of method for preparing porous fibroin membrane with freeze-drying is disclosed, the fibroin material that above technology provided all is membranaceous, only can be used as the surface of a wound and cover and artificial skin, be difficult to constitute used in tissue engineering 3 D complex support.At present, utilize the biodegradable tissue engineering bracket material of natural silk fibroin fiber production, do not appear in the newspapers as yet.

Summary of the invention

The object of the present invention is to provide a kind of and human body to have the favorable tissue compatibility, and biodegradable fibre for tissue engineering scaffold and preparation method thereof.

To achieve the above object of the invention, the technical solution used in the present invention is: a kind of fibre for tissue engineering scaffold, it is that main raw material processes with domestic silkworm silk or its goods, and described fibre for tissue engineering scaffold is a long filament shape structure, and wherein natural silk content is 95%～100%; Degree of crystallinity is 1%～40%, and fiber number is 1～40dtex, and tensile break strength is greater than 0.5cN/dtex, and elongation at break is 1～30%.

In order to reach every technical performance of above-mentioned fibre for tissue engineering scaffold, the preparation method that the present invention adopts is come unstuck silk earlier, obtains pure natural silk, carries out the processing of following steps again:

A. with the dissolving of pure natural silk, make silk concentration after the purification at 10%～40% spinning solution;

B. be that 50～99% organic solvent or concentration are that 20～60% high-hydroscopicity salt is prepared into solidification liquid with concentration,, obtain the spun filament cellulose fiber after the cleaning spinning solution spinning in coagulating bath;

C. be that 30～90% organic solvent or concentration are that 10～50% high-hydroscopicity salt is prepared into drawing-off liquid with concentration, the spun filament cellulose fiber in bathing, is carried out once or the drawing-off once in drawing-off, its draft speed is 2～120 meters/minute, the drawing-off multiplying power is 0.1～20 times, drawing temperature is 50～120 ℃, degree of crystallinity is 0%～40%, thereby obtains biodegradable tissue engineering bracket regenerated silk fiber.

In the technique scheme, described pure natural silk dissolution process, its solvent is 60～85% phosphoric acid, and solution temperature is 20～40 ℃, and dissolution time is 0.5～72 hour; Pure natural silk dissolution process also can be: the ternary solution that solvent is mixed with by weight the ratio for lithium bromide 35～50%, ethanol 45～55%, water 5～10%, and solution temperature is 60～90 ℃, dissolution time is 3～5 hours.

Organic solvent in described solidification liquid, the drawing-off liquid is a kind of in methyl alcohol, the ethanol; The high-hydroscopicity salt is that ammonium acetate, acetic acid are received, a kind of in the ammonium sulfate, sodium sulphate.

Described spinning process condition is to be spinning in 20～50 ℃ the coagulating bath with spinning solution in temperature, and nitrogen pressure is 0.1MPa～0.5Mpa, and the spinning plate aperture is 0.2～0.8mm, and spinning speed is 1～28 meter/minute.

The present invention is owing to being main raw material with silk, and therefore, the regenerated silk fibroin fiber that makes has natural fibroin protein and the good advantage of human-body biological compatibility; Simultaneously, owing to, make regenerated silk fibroin fiber biological degradable, become tissue engineering bracket with desirable fibrous material in aggregated structure parameters such as the degree of crystallinity of control regenerated silk fibroin fiber in spinning process, the degrees of orientation.

Description of drawings

Accompanying drawing 1 is the schematic diagram of embodiment of the invention spinning process flow process and apparatus structure.

The specific embodiment

Below in conjunction with drawings and Examples, the present invention is further illustrated.

Embodiment one:

Earlier 0.6 kilogram of leftover bits and pieces raw silk (byproduct in reeling mill's silk cocoon filature) is put into 10 liters of concentration and be 0.05% aqueous sodium carbonate, boiled 0.5 hour, the silk gum of most fibroin periphery is taken off in reprocessing three times, obtains pure natural silk.

Treating the pure natural silk after nature dries, is 80% phosphoric acid with 1.5 liters of concentration, and dissolving is 2 hours under 30 ℃ temperature conditions, purifies after filtration, the ultrasonic wave froth breaking makes spinning solution after 1 hour;

Referring to accompanying drawing 1, under the effect of 0.4MPa nitrogen, with the aperture spinneret orifice that is 0.5mm, under 25 ℃ temperature conditions, speed ejection fibroin albumen spinning solution with per minute 2 grams, entering concentration is in the 25% ammonium sulfate solidification liquid, and the temperature of coagulating bath is 30 ℃, and spinning is frozen into nascent fibroin fiber.To immerse first drawing-off through the nascent fibroin fiber after the washing and bathe, degree of draft is 1.0 times; Immerse second drawing-off again and bathe, degree of draft is 2.0 times.The drawing-off liquid of first and second time drawing-off is the methyl alcohol of concentration 60%, and drawing temperature is 80 ℃.

At last, batch with the speed of 90 meters of per minutes, make tissue engineering bracket regenerated silk fibroin fiber, its fibroin content is 100%, measures through X-ray diffraction, and its degree of crystallinity is 3%.Fibre length is more than 1 meter, fiber number 1dtex, and tensile break strength 0.5CN/dtex, elongation at break are 2%.

Embodiment two:

It is 0.5% neutral soap solution that 1 kilogram of cocoon layer is put into 20 liters of concentration, boils 2 hours, takes off the silk gum of most fibroin periphery, obtains pure natural silk after hot water fully washs.

Dried pure natural silk, with 1.5 liter weights ratio is 44: 50: 6 lithium bromide, ethanol, the ternary solution of water, stirs 4 hours under 75 ℃ temperature conditions, is dissolved into the fibroin mixed solution, purify after filtration, the ultrasonic wave froth breaking was made spinning solution after 1.5 hours.

As shown in Figure 1, under the effect of 0.3MPa nitrogen, be 2 of the spinneret orifices of 0.5mm with the aperture, under 30 ℃ of temperature conditions, with the speed ejection fibroin albumen spinning solution of per minute 3 gram, enter 20 ℃ of methanol concentrations and be in 60% the solidification liquid, be frozen into nascent fibroin fiber.

Immerse first drawing-off and bathe after washing, drawing-off liquid is 15% ammonium acetate solution, and temperature is 70 ℃, and degree of draft is more than 1.5 times; Immerse second drawing-off again and bathe, drawing temperature is 80 ℃, and drawing-off liquid is 10% ammonium acetate solution, and degree of draft is more than 2.0 times.

Batch with the speed of 90 meters of per minutes at last, make fibroin content and be 95%, degree of crystallinity is 6% tissue engineering bracket regenerated silk fibroin fiber.

Tissue engineering bracket fibroin fiber provided by the invention has kept the protein composition of natural fibroin, has excellent biological compatibility, and with low cost.Particularly its biodegradability reaches the plasticity of being processed into the used in tissue engineering three-dimensional rack by the road, back, be expected as replacing expensive biodegradable tissue engineering materials such as import PLA, as artificial skin, tissue engineering rack material or surgical repair materials such as tendon, blood vessel, cartilage, ligament, esophagus, endocranium.

Claims

1. A fiber for tissue engineering support, characterized in that: it is processed from silkworm silk or its products as the main raw material, and the fiber for tissue engineering support is a filamentous structure, wherein the silk fibroin content is 95% ~100%; the crystallinity is 1%~40%, the fineness is 1~40dtex, the tensile breaking strength is greater than 0.5cN/dtex, and the elongation at break is 1~30%.

2. A method for preparing tissue engineering support fibers, first silk degumming, to obtain pure silk fibroin, is characterized in that the processing of the following steps is carried out again:

a. Dissolving and purifying pure silk fibroin to obtain a spinning stock solution with a silk concentration of 10% to 40%;

b. prepare a coagulation solution with an organic solvent with a concentration of 50-99% or a superabsorbent salt with a concentration of 20-60%, spin the spinning stock solution in a coagulation bath, and obtain primary silk fibers after cleaning;

c. use a concentration of 30% to 90% organic solvent or a concentration of 10% to 50% superabsorbent salts to prepare a drawing solution, and draw the primary silk fiber in the drawing bath once or more than once, The drawing speed is 2-120 m/min, the drawing ratio is 0.1-20 times, the drawing temperature is 50-120°C, and the crystallinity is 0%-40%, so as to obtain regenerated silk for biodegradable tissue engineering scaffolds vegan fiber.

3. A method for preparing fibers for tissue engineering scaffolds according to claim 2, characterized in that: in the pure silk fibroin dissolving process, the solvent is 60-85% phosphoric acid, at a temperature of 20-40°C Dissolve under the conditions of 0.5 to 72 hours.

4. a kind of method for preparing tissue engineering support fiber according to claim 2, is characterized in that: described silk fibroin dissolving process, solvent is lithium bromide 35～50%, ethanol 45～55%, water 5% by gravity. The ternary solution formulated at a ratio of ~10% is dissolved at a temperature of 60-90° C. for 3-5 hours.

5. a kind of method for preparing tissue engineering support fiber according to claim 2, is characterized in that: the organic solvent in described coagulation liquid, drafting liquid is the one in methyl alcohol, ethanol; Superabsorbent salt The class is one of ammonium acetate, sodium acetate, ammonium sulfate, and sodium sulfate.

6. A method for preparing fibers for tissue engineering scaffolds according to claim 2, characterized in that: the spinning process conditions are spinning the spinning stock solution in a coagulation bath with a temperature of 20-50°C , the nitrogen pressure is 0.1MPa～0.5Mpa, the hole diameter of the spinneret is 0.2～0.8mm, and the spinning speed is 1～28m/min.