CN1126515C - Medical artificial nerve graft and preparation process thereof - Google Patents

Abstract

The invention discloses a medical artificial nerve graft and a preparation method thereof, which comprises a biological conduit, and a fiber support is embedded in the biological conduit. The preparation method includes preparing biological conduits with chitosan, polyglycolic acid, and polylactic acid, preparing fiber scaffolds with polyglycolic acid or polylactic acid, and embedding the fiber scaffolds in the biological conduits. The medical artificial nerve graft prepared by the invention is beneficial to the growth of the nerve, and makes the recovery of the damaged nerve better, and the preparation method is convenient and reliable.

Description

Medical artificial nerve graft and preparation method thereof

The present invention relates to a graft for bridging defective nerves.

Peripheral nerve defect is a difficult problem in the treatment of orthopedics, microsurgery, trauma surgery, and war wound surgery. Although modern microsurgery techniques are highly accurate, the functional recovery rate after peripheral nerve injury repair is still unsatisfactory. People will further Hopes for improving peripheral nerve rehabilitation rest on breakthroughs in basic research. The main forms of applying polyglycolic acid (PGA), polylactic acid (PLA) and their copolymers in tissue engineering abroad are fibrous scaffolds and tubular structures.

The purpose of the present invention is to provide a kind of medical artificial nerve graft and its preparation method which is beneficial to the growth of nerves and recovers the damaged nerves.

Technical solution of the present invention is:

A medical artificial nerve graft includes a biological conduit, and a fiber support is embedded in the biological conduit.

The bioconduit material is chitosan, polyglycolic acid, polylactic acid, and the fiber scaffold material is polyglycolic acid or polylactic acid. Biological catheters are foam-like tubes of polyglycolic acid or polylactic acid material. The diameter of the medical artificial nerve graft is 2.0-4.0mm. The length of the medical artificial nerve graft is 3.0-6.0cm.

A method for preparing a medical artificial nerve graft, comprising the following steps:

1) prepare biological conduit with chitosan or polyglycolic acid, polylactic acid;

2) preparing fiber scaffolds with polyglycolic acid or polylactic acid;

3) Embedding the fiber scaffold prepared in 2) into the biological catheter prepared in 1).

Wherein the method for making chitosan biological conduit is:

1) chitosan is dissolved in acetic acid solution;

2) adding glutaraldehyde to carry out cross-linking reaction;

3) add surfactant to carry out activation treatment;

4) Pour the solution obtained through the above steps into a mold for molding.

The specific steps of step 1) in the above-mentioned method for manufacturing chitosan biological conduits are: the chitosan with a deacetylation degree of 80-85% is dissolved in 1-3% acetic acid solution; the specific steps of step 2) are : solution is heated up to 70～90 ℃, adds the glutaraldehyde of 0.5～3 times of chitosan amount, carries out cross-linking reaction 0.5～3 hours, cools down to normal temperature; Step 3) concrete steps are: Surfactant Siben 85 with 0.5 to 1.5 times the amount of polysaccharide and Tween 20 equivalent to 0.5 to 1.5 times the amount of chitosan, the solution is fully stirred and left to stand; the specific steps of step 4) are: The resulting solution is poured into molds and dried to remove volatile substances.

The method for preparing polyglycolic acid or polylactic acid foamed biological catheter is: polyglycolic acid or polylactic acid is processed into a tubular structure through conventional molding, and then placed in 3-10MPa carbon dioxide high-pressure gas, until the carbon dioxide gas is in the polyethanol It is dissolved and saturated in acid or polylactic acid, and then the air pressure is lowered to form a foamy tubular structure.

The medical artificial nerve graft prepared by the present invention adopts chitosan, polyglycolic acid, and polylactic acid materials, all of which are biodegradable materials, have good biocompatibility with the human body, have no adverse reactions, and have a relatively fast degradation rate. Slow, which provides sufficient time guarantee for the repair of nerve damage; the structure adopts the combination of PGA, PLA tube and fiber scaffold, so that the composite tube has certain mechanical strength and toughness, and provides a smooth space for the growth of nerve cells. At the same time, it provides the necessary induction to guide the orderly growth of nerve cells; the tube wall adopts a foam-like porous structure, which provides a necessary way for the delivery of nutrients required for the growth of nerve cells, and the recovery of nerve damage is good. The preparation method of the invention is convenient and reliable.

The present invention will be further described below in conjunction with embodiment.

Example 1:

1) prepare biological conduit with chitosan: the chitosan that the deacetylation degree is 80～85% (example 80%, 28%, 85%) is dissolved in 1～3% (example 1%, 2%, 3% ) in the acetic acid solution, the above solution is heated to 70 ~ 90 ℃ (example 70 ℃, 80 ℃, 90 ℃), add 0.5 ~ 3 times (example 0.5, 1, 2, 3 times) to the amount of chitosan Glutaraldehyde, carry out cross-linking reaction 0.5～3 hours (example 0.5, 1, 2, 3 hours), cool down to normal temperature; Siben 85 and Tween 20 equivalent to 0.5 to 1.5 times the amount of chitosan (for example, 0.5, 1, 1.5 times), fully stir the solution, and let it stand for more than 24 hours; pour the solution obtained through the above steps into the prepared Shaped in a tubular mold (2.0 ~ 4.0mm × 3.0cm ~ 6cm), and dried to remove volatile substances.

2) Fabrication of fiber scaffolds with polyglycolic acid (PGA): Extrusion into fibers of 10-15 μm by conventional methods in the prior art, and scaffolds of different shapes and thicknesses.

3) Embedding the fibrous scaffold prepared in 2) into the biological conduit prepared in 1) by conventional micromanipulation methods.

Example 2:

The fiber scaffold is made of polylactic acid (PLA) material, processed into fibers of 10-15 μm by extrusion molding by conventional methods in the prior art, and made into scaffolds of different shapes and thicknesses. All the other are with embodiment 1.

Example 3:

Polyglycolic acid or polylactic acid is used to manufacture foam-shaped biological catheters: polyglycolic acid or polylactic acid is plastic-molded into a tubular structure (2.0-4.0mm×3.0cm-6cm) by conventional methods, and then placed at 3-10MPa (Example 3, 5, 7, 10MPa) In the carbon dioxide high-pressure gas, until the carbon dioxide gas is dissolved and saturated in polyglycolic acid or polylactic acid, and then the air pressure drops to about one atmospheric pressure, the solubility of carbon dioxide in the polymer drops rapidly, producing a large amount of gas cavities, eventually forming a foamy tubular structure. All the other are the same as in Example 1.

Example 4:

The fiber scaffold is made of polylactic acid (PLA) material, processed into fibers of 10-15 μm by extrusion molding by conventional methods in the prior art, and made into scaffolds of different shapes and thicknesses. All the other are with embodiment 3.

Claims (7)

1. A medical artificial nerve graft, characterized in that: it includes a biological conduit made of chitosan material, and the biological conduit is embedded with a fiber support. 2. The medical artificial nerve graft according to claim 1, characterized in that: the fiber scaffold material is polyglycolic acid or polylactic acid. 3. The medical artificial nerve graft according to claim 1 or 2, characterized in that the diameter of the medical artificial nerve graft is 2.0-4.0 mm. 4. The medical artificial nerve graft according to claim 1 or 2, wherein the length of the medical artificial nerve graft is 3.0-6.0 cm. 5. A method for preparing a medical artificial nerve graft, characterized in that it comprises the following steps: 1) prepare biological conduit with chitosan; 2) preparing fiber scaffolds with polyglycolic acid or polylactic acid; 3) Embedding the fiber scaffold prepared in 2) into the biological catheter prepared in 1). 6, the preparation method of medical artificial nerve graft according to claim 5 is characterized in that: the method for manufacturing chitosan biological conduit is: 1) chitosan is dissolved in acetic acid solution; 2) adding diperaldehyde to carry out cross-linking reaction; 3) add surfactant to carry out activation treatment; 4) Pour the solution obtained through the above steps into a mold for molding. 7. The preparation method of medical artificial nerve graft according to claim 6, characterized in that: the specific step of step 1) is: dissolving chitosan with a degree of deacetylation of 80-85% in 1-3% Dissolving in the acetic acid solution; the specific steps of step 2) are: heating the solution to 70-90° C., adding 0.5-3 times the chitosan amount of dipentaldehyde, performing a cross-linking reaction for 0.5-3 hours, and cooling to normal temperature; The specific steps of step 3) are: adding surfactant Siben 85 equivalent to 0.5 to 1.5 times the amount of chitosan and Tween 20 equivalent to 0.5 to 1.5 times the amount of chitosan, fully stirring the solution, and standing; The specific steps of step 4) are: pour the solution obtained through the above steps into a mold for molding, and dry to remove volatile substances.