CN2712308Y - Special die for making axial multichannel nerve conduit - Google Patents

Abstract

The utility model discloses a special mould for making an axial multichannel nerve conduit, comprising a base, two mobile plates arranged on the base, a stainless steel needle, and two steel needle fixing pieces fixed on the mobile plates. Each steel needle fixing piece is provided with 7-50 steel needle fixing holes matching with the diameter of the steel needles, and the hole diameter is 200-500 mu m. The steel needle fixing holes are evenly distributed in a circular area whose diameter is 1-5mm. The utility model is processed and produced with the nerve conduit with axial multichannel special microstructure stroma by using biologic source materials, with convenient operation, and is favorable for adding biologic active materials in the stroma materials. With the mould, the ideal axial multichannel nerve conduit can be produced for repairing peripheral nerve damage.

Description

A special mold for making axial multi-channel nerve guide

technical field

The utility model relates to a special mold for making an axial multi-channel nerve guide, which belongs to the technical field of biomedical materials and tissue engineering.

Background technique

Peripheral nerve injury is very common in clinical practice, which brings great inconvenience to patients' lives. At present, peripheral nerve defect is mainly repaired clinically by autologous nerve transplantation, but autologous nerve transplantation will inevitably lead to loss of nerve function in the donor site. People try to use various natural and artificial catheters to bridge nerve defects, such as autologous veins, silicone tubes and hollow catheters made of PLGA, collagen, chitosan, etc., but the effect is not ideal, mainly because of the gap between these catheters and the normal nerve structure Very far, it is not conducive to the attachment and extension of axons, and it is difficult to preset enough Schwann cells. The excess space in the tube is quickly filled by hematoma, which hinders the growth of axons. In view of this, people began to consider filling the catheter with matrix material to increase the surface area for axon growth, or to carry cells and nutritional factors. Chinese patent application 00810000.4 provides a nerve conduit made of polyester material. The lumen is filled with collagen hydrochloric acid solution and freeze-dried to obtain a collagen content with fine fibrils. However, this method is difficult to obtain a multi-channel structure with axial penetration ; Chinese patent application 02113103.1 puts chitosan fibers into chitosan tubes to prepare pure chitosan nerve guides; Chinese patent application 02105864.4 places folded and curled porosity with concave-convex surfaces in hollow tubes made of polyester materials Polyester films are used to increase the surface area of the cavity to make multi-channel nerve regeneration catheters. However, the contents of the above-mentioned catheters are in a free state, cannot maintain a stable structure, and are difficult to preset cells; US Patent US 5925053 (1999), US 6214021 (2001) provided a method for making a multi-lumen nerve guide. In this method, a number of thin fibers are placed in the mold in advance, and then a polymer solution containing an organic solvent is injected into the mold, and then solidified by freezing. Then the solvent in the material is extracted by sublimation, and finally the thin fibers are drawn out to form a multi-lumen nerve conduit. However, the nerve conduit obtained by this method has no outer wall, and the fibrous tissue is easy to invade. The polymer materials used such as PLGA, PGA, PLA The degradation of acidic products in vivo is not conducive to axon growth, and the organic solvents used are not conducive to loading nutrient factors.

An ideal scaffold for nerve tissue engineering should simulate the normal nerve structure, provide axial fine channels for axonal growth and neurotrophic factors, and carry cells that are beneficial to nerve repair and regeneration; it should not only prevent the invasion of fibrous scar tissue, but also It is necessary to allow the new tissue cells inside the catheter to exchange normal body fluids with the outside of the catheter; the scaffold should have the shape of a nerve, a stable structure, a suitable pore size, porosity and permeability of the outer wall. The matrix structure inside the scaffold should have dense axial channels and laterally permeable micropores, and this stable structure is conducive to cell adhesion, migration and guiding axon regeneration. The technologies that can be used to make such nerve guides are: (1) particulate-leaching techniques; (2) heat compression and extrusion techniques; (3) solid free-forming manufacturing (solid free-form fabrication), also called rapid prototyping technology. However, the catheter-guided axonal regeneration ability of random structures made by particle leaching pore-making technology is unreliable, and hot-extrusion technology cannot add therapeutic drugs or factors to the matrix material, because the mechanical processing and heat treatment process will make them Denaturation or degradation, and the current hot extrusion technology is not suitable for making small-bore catheters suitable for nerve repair. Rapid prototyping technology simulates the principle of inkjet printers to print three-dimensional organs, but due to the limitation of materials, some biological materials (such as collagen and chitosan) cannot be applied to this method, and drug factors can not tolerate such a processing process. limit its application. Therefore, it has important practical application value to invent a more ideal technical method for preparing multi-channel nerve guide and the tool means for realizing this method.

Utility model content

The purpose of the utility model is to provide a special mold for making a multi-channel nerve guide.

The technical scheme of the utility model is as follows:

A special mold for making axial multi-channel nerve conduits, characterized in that the mold includes a base, two movable plates arranged on the base, stainless steel needles and two steel needle fixing pieces fixed on the movable plates ; There are 7 to 50 steel needle fixing holes matching the diameter of the steel needle above each of the steel needle fixing pieces, and the hole diameter is 200 to 500 μm; the steel needle fixing holes are evenly distributed in the In a circular area with a diameter of 1-5mm.

The mold is beneficial to use biological source materials (such as chitosan, collagen, gelatin) to process and manufacture a nerve conduit with an axial multi-channel matrix, and the mold is easy to operate and is beneficial to add biologically active substances into the matrix material. The pore size of the channel and the size of the permeable micropores are adjustable, which is conducive to the repair of nerve damage by pre-preparing Schwann cells.

Description of drawings

Fig. 1 is the structural representation of the utility model.

Fig. 2 is a left view of the utility model.

Detailed ways

The best embodiment of the utility model and its application method will be further described below in conjunction with the accompanying drawings.

The mold mainly includes a base 4, two movable plates 3, a plurality of stainless steel needles 7 and two steel needle fixing pieces 1, the movable plates are fixed on the base 4 by fixing screws 5, and the movable plates are 3. It can be adjusted left and right on the base according to the length of the prepared nerve guide. The top of each movable plate fixes a steel needle fixed piece by set screw 2. There are 7 to 50 steel needle fixing holes 8 that match the diameter of the steel needle above each of the steel needle fixing pieces, and the hole diameter is 200 to 500 μm; the steel needle fixing holes are evenly distributed in the In a circular area with a diameter of 1-5mm. The steel needle fixed sheet can be made of copper sheets or other metal sheets and plastic materials.

The method for preparing the chitosan multi-channel nerve guide using the provided mold is illustrated below by way of example.

As shown in the accompanying drawings, a certain length of hollow tube 6 is placed between the two steel needle fixing pieces 1 on the special mold (Fig. 200-500 μm), the corresponding number and diameter of stainless steel needles 7 are parallelly penetrated through the bilateral steel needle fixing holes 8 and the hollow tube 6 . Then fill the hollow tube with the biological source matrix material, move the movable plates 3 on both sides of the mold inward, make the double-sided steel needle fixed piece closely contact with the two ends of the hollow tube, and tighten the movable plate fixing screws 5, Quickly freeze and dry together with the mold, then deacidify and dry naturally. The stainless steel needles were slowly taken out one by one, and finally the desired nerve guide with axially arranged multi-channel matrix was obtained.

Claims (1)

1. A special mold for making axial multichannel nerve guides is characterized in that: the mold includes a base (4), two movable plates (3) arranged on the base, stainless steel needles (7) and fixed on Two steel needle fixing pieces (1) on the movable plate; 7 to 50 steel needle fixing holes (8) matching the diameter of the steel needles are arranged above each of the steel needle fixing pieces, The hole diameter is 200-500 μm; the steel needle fixing holes are uniformly distributed in a circular area with a diameter of 1-5 mm.

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