JP4883141B2 - Manufacturing method of medical collagen monofilament - Google Patents

Description

  The present invention relates to a method for producing a collagen single yarn suitable for medical use. Specifically, sutures used for medical purposes in vivo or on the body surface of a living body, various membranes, cloths, bags and tubulars for the purpose of compensation and prosthesis in the field of tissue engineering / regenerative medicine, or The present invention relates to a method for producing a collagen single yarn necessary for producing a pharmaceutical carrier or the like.

Collagen is a major protein that constitutes a living body, and has excellent effects such as biocompatibility, tissue regeneration, cell proliferation, and hemostasis, and is therefore a useful material particularly in the medical field. In the production of medical base materials using these collagens, animal or human tissues are directly processed, and the collagen shape is mainly used as it is while maintaining the shape of the tissues, or this is further processed. In some cases, these are difficult to process arbitrarily as shapes and dosage forms of easy-to-use medical devices, and there are problems because the antigenic expression site of collagen remains intact.
Therefore, collagen that is usually suitable for medical use is a viscous collagen solution or a solid state obtained by extracting this solution from an animal, which is a raw material, with an enzyme or the like under conditions of acid, alkali, neutrality, and the like. The method obtained as is generally used. Furthermore, the antigenic expression site can be removed by pepsin treatment, and collagen (atelocollagen) more suitable for a medical substrate that is not antigenic when transplanted into the body or body surface can be obtained.
As a method for producing a medical substrate from a collagen solution, a collagen solution is freeze-dried to produce a sponge-like substrate, or a collagen solution is spun by a wet or dry spinning method to obtain a fibrous substrate. A method of manufacturing a material is known.

Japanese Patent Application Laid-Open No. 06-228505 discloses a method of obtaining a collagen filamentous material or membrane by discharging a collagen aqueous solution into a hydrophilic organic solvent. This technique is a method for producing collagen filaments (or membranes) as an intermediate product, and as a final product, soluble collagen granules (powder) obtained by chopping collagen filaments are obtained. Japanese Patent Application Laid-Open No. 06-228506 describes a method in which a collagen solution is discharged into a 75 to 85% ethanol medium to form a filamentous material and then immersed in 95 to 99.5% or more of an alcohol medium. Yes. In these documents, a collagen filamentous material is prepared and then dried at 60 ° C., and the collagen filamentous material is exposed to a temperature far exceeding its denaturation temperature.
In JP 2000-093497, JP 2000-210376, and 2000-271207, a collagen aqueous solution is discharged into a hydrophilic organic solvent such as ethanol, the collagen is shaped into a filament, and the collagen aqueous solution discharge port is randomly and vertically aligned. And a method of preparing a laminated structure of collagen yarns by allowing it to settle at the bottom of an ethanol tank while being moved to the position.

Japanese Patent Laid-Open No. 06-228505 Japanese Patent Laid-Open No. 06-228506 JP 2000-093497 A Japanese Patent Laid-Open No. 2000-210376 JP 2000-271207 A

  The filamentous collagen obtained by the conventional method is extremely weak in strength, and breakage of yarn occurs during winding of the yarn. In addition, since the obtained yarns mutually adhere to each other, when the obtained yarn is wound around a winder, the yarn breakage occurs even if the yarn is taken out again and it is difficult to take out as a single yarn. Met. Therefore, when taking up filamentous collagen, there is no yarn breakage, and there is no adhesion between the yarns in the wound state, and there is no yarn breakage when taking out the yarn again after winding up. Development of a manufacturing method is demanded.

The present inventors succeeded in obtaining collagen as a continuous single yarn by processing collagen into a yarn using a spinning method using a hydrophilic organic solvent. The inventors have found that the collagen single yarn can be processed into various arbitrary shapes including cloth and tube and is very useful in medical applications such as medical devices, culture substrates, and drug carriers.
As a result of further intensive studies based on these findings, the present invention has been completed.

That is, the present invention is (1) dehydrating a collagen solution in a hydrophilic organic solvent having a water content of 50% or less, then dehydrating and coagulating with a water content of 10% or less, and maintaining the tension, while maintaining a relative humidity of 50% or less, A method for producing a medical collagen monofilament characterized by drying under conditions of a temperature of 42 ° C. or lower,
(2) The method for producing a medical collagen single yarn according to (1), wherein the collagen single yarn is further subjected to a crosslinking reaction treatment after drying,
(3) The method for producing a medical collagen single yarn according to (1), wherein the collagen single yarn is for medical use,
(4) The medical collagen single yarn according to (1) above, wherein the hydrophilic organic solvent is selected from the group consisting of alcohols and ketones having 1 to 6 carbon atoms, or a mixture of two or more kinds. Production method,
(5) The method for producing a medical collagen single yarn according to (1), wherein the hydrophilic organic solvent is ethanol,
(6) The method for producing a medical collagen single yarn according to the above (1), wherein the drying is air drying.
(7) The method for producing a single collagen fiber for medical use according to (1), wherein the relative humidity is 30% or less,
(8) The method for producing a medical collagen monofilament according to (1), wherein the temperature is dried under a condition of 10 to 42 ° C,
(9) The method for producing a single collagen fiber for medical use according to (1), wherein the crosslinking reaction treatment is a heat dehydration treatment and / or a glutaraldehyde treatment,
(10) The method for producing a single collagen fiber for medical use according to (1), wherein the collagen is derived from pigs.

  By using the method for producing a collagen single yarn of the present invention, yarn breakage does not occur, and a collagen single yarn can be continuously obtained until the raw collagen aqueous solution is exhausted. The collagen single yarn produced by the method of the present invention does not adhere to each other, and can be smoothly taken out from the winder. In addition, a medical device such as a collagen tubular product or a cloth product can be easily and efficiently produced from a collagen single yarn by a technique usually used in the fiber production field such as weaving and knitting. Collagen medical devices having a complicated three-dimensional structure from collagen single yarn produced by the method of the present invention, and collagen medical devices with higher precision and reproducibility can be easily produced. Further, as a medical device material using collagen, it can be stored and transported under normal environmental conditions while being wound around the winder.

It is explanatory drawing which shows Example 1 of this invention. It is explanatory drawing which shows Example 3 of this invention. It is explanatory drawing of the measuring method of Experimental example 1. FIG. It is a substitute photograph which replaces drawing which shows the base material engraftment of the cell of Example 4, and the mode of proliferation. It is a substitute photograph substituted for drawing which shows the mode of substrate engraftment and proliferation of the cell of Example 5. 10 is a substitute photograph replacing a drawing showing a stained image of Example 6. FIG. 10 is a substitute photograph replacing a drawing showing a stained image of Example 6. FIG.

1. 1. Plate take-up tool 2. Collagen single yarn Syringe 41. Ethanol bath 42. Second ethanol tank 51. Blower dryer 52. Tension pulley 53. Hook 6. 6. Roll-shaped winder Glutaraldehyde solution tank 81. Tape 811. Punch hole 82. Tape 83. Force gauge 831. hook

The method of the present invention comprises (1) a step of spinning a collagen solution into a filamentous collagen by a spinning method using a hydrophilic organic solvent, and coagulating the filamentous collagen in a hydrophilic organic solvent having a water content of about 10% or less; (2) a relative humidity of about The drying is performed under the conditions of 50% or less and a temperature of about 42 ° C. or less.
In step (1), (i) the collagen solution may be discharged into a hydrophilic organic solvent having a water content of about 10% or less, and the filamentous collagen may be dehydrated and coagulated in a state where the water content is about 10% or less. (ii) After the above operation (i), it may be further strongly dehydrated and coagulated in another hydrophilic organic solvent having a water content of 10% or less. (iii) The collagen solution is discharged into the hydrophilic organic solvent to contain water. Once filamentous collagen is formed in a hydrophilic organic solvent with a rate of more than about 10% (dehydration step), this filamentous collagen is further dehydrated and coagulated in a hydrophilic organic solvent with a water content of about 10% or less (dehydration / coagulation step). May be. This step is usually performed at room temperature to about 42 ° C., and the treatment time by a series of dehydration and coagulation is about 4 to 5 seconds to 5 hours.
Representative collagens used in the method of the present invention include solubilized collagens such as acid-solubilized collagen, alkali-solubilized collagen, enzyme-solubilized collagen and neutral-solubilized collagen. Atelocollagen, which has been subjected to removal of telopeptides that are antigenic determinants, is preferred. This method for solubilizing collagen is described in Japanese Patent Publication No. 46-15003, Japanese Patent Publication No. 43-259839, Japanese Patent Publication No. 43-27513, and the like. The origin of collagen is extracted from the skin, tendon, bone, cartilage, organ, etc. of animal species such as cattle, pigs, birds, fish, rabbits, sheep, mice, humans, etc. Although not limited to any type that can be classified such as type and type III, type I is particularly preferable from the viewpoint of handling.
The solvent for the collagen solution is not particularly limited as long as it can solubilize collagen. Typical examples include a dilute acid solution such as hydrochloric acid, acetic acid, and nitric acid, a liquid mixture of a hydrophilic organic solvent such as ethanol, methanol, and acetone and water, and water. You may use these individually or in mixture of 2 or more types in arbitrary ratios. Of these, water is most preferred.

In the first step (1), the collagen solution is continuously discharged from a nozzle or the like into a bath filled with a hydrophilic organic solvent, and dehydrated and solidified to obtain filamentous collagen. The collagen concentration of the collagen solution is usually about 4 to 10% by weight, preferably about 5 to 7% by weight.
Examples of the hydrophilic organic solvent include alcohols having 1 to 6 carbon atoms such as ethanol, methanol and isopropanol, and ketones such as acetone and methyl ethyl ketone. You may use these individually or in mixture of 2 or more types in arbitrary ratios. Of these, ethanol is most preferred. The water content of the hydrophilic organic solvent is usually about 50% by volume or less, preferably about 30% by volume or less in order to obtain filamentous collagen from the collagen aqueous solution (dehydration step). For the step) is usually about 10% by volume or less, preferably about 2% by volume or less, more preferably about 0.5% by volume or less.
As for the bathtub filled with the hydrophilic organic solvent, you may install one independent bathtub, or about 2 to 20 independent tanks continuously as needed. In the case of using one independent bath, the hydrophilic organic solvent is cyclically replaced so that the dehydration process is finally performed at about 10% by volume or less, and the water content is maintained at about 10% by volume or less. When a plurality of independent tanks are used, at least one tank in the final dehydration step maintains the water content of the hydrophilic organic solvent at about 10% by volume or less for the coagulation treatment of the filamentous collagen. At this time, a yarn suitable for medical use can be obtained due to the excellent bactericidal effect of the hydrophilic organic solvent.
Filamentous collagen is dehydrated and coagulated and then dried under conditions of a relative humidity of about 50% or less and a temperature of about 42 ° C or less. The relative humidity is preferably about 30% or less. The drying temperature is preferably about 10 to 42 ° C, more preferably about 10 to 20 ° C. The drying time is usually about 1 to 2 seconds to 5 hours depending on the solvent content. In this drying process, a dry gas kept in a clean state that has passed through various filters and the like is blown onto the collagen single yarn. The dry gas is not particularly limited as long as it is an inert gas that does not affect collagen, such as air and nitrogen, and air is the most suitable. The collagen single yarn moving in the direction of the winder is always exposed to dry air, so that the liquid component remaining in the filamentous material is dried and removed, and the yarns wound on the winder are inside the yarn. In addition, liquid components such as a solvent remaining on the outer surface can be re-dissolved and prevented from adhering to each other. This dry gas is an air stream that is not heat-treated and has a temperature of about 42 ° C. or less and a relative humidity of about 50% or less, and heat denaturation of the collagen single yarn does not occur.

  The collagen single yarn that has undergone the drying process is wound around a winder as necessary. In the present winding process, the shape of the winder is not particularly limited, and examples thereof include a plate shape, a columnar shape (roll shape), and the like to rotate and wind up the filamentous material. At this time, the winder itself reciprocates in the axial direction at a constant speed, or the collagen single yarn reciprocates in the axial direction of the winder using a hook that automatically reciprocates. Therefore, it is preferable that the collagen single yarn has a mechanism that can be uniformly wound around the winder.

In order to enhance the strength of the collagen single yarn, it may be subjected to a chemical crosslinking reaction using a crosslinking by a physical crosslinking treatment or a crosslinking agent. Examples of the physical crosslinking treatment include γ-ray irradiation, ultraviolet irradiation, electron beam irradiation, plasma irradiation, and thermal dehydration crosslinking treatment. Of these, thermal dehydration crosslinking is preferred. In the thermal dehydration cross-linking treatment, the cross-linking treatment is physically performed by heat treatment under reduced pressure in a state where the collagen single yarn is wound. In this crosslinking treatment, biocompatibility and decomposition absorbability can be controlled by the crosslinking temperature and crosslinking time. Physical cross-linking and chemical cross-linking may be performed independently or in combination, and the order of the cross-linking is not particularly limited.
As the crosslinking agent used for the chemical crosslinking reaction, any crosslinking agent can be used as long as the crosslinking reaction with collagen is possible, and examples thereof include aldehydes, epoxies, carbodiimides, isocyanates and the like. Examples of aldehydes include formaldehyde, glutaraldehyde, glyoxal and dialdehyde starch, examples of epoxies include glycerol diglycidyl ether, examples of carbodiimides include water-soluble carbodiimide, and examples of isocyanates include hexamethylene diisocyanate. Glutaraldehyde is preferred. The collagen single yarn is usually crosslinked by immersing the collagen single yarn in a solution of a crosslinking agent. The solvent for the crosslinking agent solution is not particularly limited, but water, ethanol, and the like are preferable, and ethanol is particularly optimal. It is possible to control the degradation absorbability and biocompatibility by the concentration of the crosslinking agent solution and the immersion time. When the crosslinking agent is glutaraldehyde, the concentration of the solution is usually about 0.001% to 25% by volume, preferably about 0.01% to 1.0% by volume.

  Immediately after the above-described series of dehydration and coagulation steps, a bath filled with a crosslinking agent solution may be installed and subjected to crosslinking treatment. The collagen single yarn formed by dehydration and coagulation treatment in an ethanol bath is removed from the last hydrophilic organic solvent bath and immediately immersed in a cross-linking agent solution bath and subjected to cross-linking treatment as necessary. Thereafter, the collagen single yarn is removed from the cross-linking agent solution tank and wound around a winder. One or more hydrophilic organic solvent tanks may be installed between the cross-linking agent solution tank and the collagen single yarn winder. By this operation, the collagen single yarn is removed from the crosslinking agent solution tank and then immersed in the hydrophilic organic solvent tank, so that the excess crosslinking agent remaining in the collagen single yarn can be washed and removed.

Further, before the collagen single yarn is wound, a dry gas kept in a clean state by passing through various filters or the like is blown. The dry gas is not particularly limited as long as it is an inert gas that does not affect collagen, such as air and nitrogen, and air is the most suitable. In this process, the collagen single yarn moving in the direction of the winder is always exposed to dry gas, so that the liquid component remaining in the collagen single yarn is dried and removed, and the wound yarns are Re-dissolves due to the liquid components remaining on the inner and outer surfaces and prevents them from sticking together. This gas is an unheated gas of low temperature (preferably 42 ° C. or less) and low humidity (preferably relative humidity of about 50% or less), and the collagen single yarn is not thermally denatured. All of these series of steps may be performed in an environment where the relative humidity is about 50% or less, preferably about 30% or less. By promoting the drying of the collagen single yarn from which the hydrophilic organic solvent tank has been removed, the occurrence of yarn breakage is promoted. And the mutual adhesion due to moisture absorption of the collagen single yarn wound on the winder can be prevented. In this production method, single independent collagen single yarns having no mutual adhesion can be produced until the aqueous collagen solution as a raw material is exhausted without causing thermal denaturation.
And since this collagen single yarn is a collagen single yarn which has no mutual adhesion and is highly independent and long connected, it is possible to smoothly take out the collagen single yarn from the winding device after the spinning is completed. In this way, a collagen single yarn subjected to chemical crosslinking treatment is produced.

As another embodiment of the chemical cross-linking treatment of collagen single yarn, the following method is also exemplified.
Collagen treatment is performed by immersing the collagen single yarn continuously drawn out from the winder in which the collagen single yarn not subjected to crosslinking treatment is wound in a crosslinking agent solution tank, and then removing the crosslinking agent solution tank. After drying, wind it up on a new winder. If necessary, at least one or more hydrophilic organic solvent tanks may be installed between the crosslinking agent solution tank and the winder for winding the collagen single yarn. That is, after the collagen single yarn is removed from the cross-linking agent solution tank, it is immersed in a hydrophilic organic solvent tank, and excess cross-linking agent remaining in the collagen single yarn that may lead to the development of toxicity is washed and removed.
The collagen single yarn that has been subjected to the cross-linking treatment is significantly improved in strength compared to the collagen single yarn that has not been cross-linked, so secondary processing such as the manufacture of tubular materials and the production of cloth-like materials using this collagen single yarn. Becomes simpler, and more robust secondary processed products can be manufactured.

Since the collagen single yarn of the present invention is a single yarn having a high degree of independence without mutual adhesion, the collagen single yarn can be smoothly taken out from the winder after the spinning is completed. For this reason, it can be suitably used as a suture thread used for medical purposes in vivo or on the surface of a living body.
In addition, through the process of weaving and knitting using such a single yarn, not only a collagen tubular product or a collagen cloth product, but also a complicated collagen three-dimensional structure can be produced.
Furthermore, since the collagen single yarn obtained by the present invention maintains the inherent function that collagen originally possesses, it is decomposed and absorbable in vivo and on the body surface, and regenerated as a scaffold for tissue regeneration. It also has excellent effects suitable for medical use such as promoting effects and hemostasis and biocompatibility.
As the secondary processed product using the collagen single yarn of the present invention, for example, various membranes, cloths, bags, and tubes transplanted into the body for the purpose of compensation and prosthesis in the fields of tissue engineering and regenerative medicine Etc. (base material for transplantation). The transplant base material is prepared by culturing cells that form body tissues such as fibroblasts and chondrocytes in advance for a certain period of time in advance according to a conventional method, and then growing the cells into the shape of the transplant base material to form the tissue. It may be transplanted into the body. Examples of the membranous material include alternative membranes such as pericardium, pleura, cerebral dura mater, and serosa. Examples of the tubular material include artificial blood vessels, stents, artificial nerve channels, artificial trachea, artificial esophagus, and artificial ureter. Moreover, it can utilize also as a base material (cell culture base material) for culturing various cells, such as adhesive cells, outside the body. Furthermore, it is used as a sustained-release DDS carrier or a gene therapy carrier by impregnating various growth factors, drugs, vectors and the like into secondary processed products of various shapes. These secondary processed products have little toxicity and can be safely used for humans and animals according to a method known per se.

  Next, the present invention will be described in detail with reference to examples and experimental examples.

Example 1 Manufacture of collagen single yarn Pig-derived type I and type III mixed collagen powder (manufactured by Nippon Ham Co., Ltd., SOFD type, Lot No. 0102226) was dissolved in distilled water for injection (manufactured by Otsuka Pharmaceutical Co., Ltd.), 7 weight %. Then, after maintaining the relative humidity of the entire spinning environment to be 38% or less to be described later, the syringe 3 (Disposable Barrels / Pistons, 55 cc manufactured by EFD) filled with this 7% by weight collagen aqueous solution is pneumatically attached to the syringe. The collagen aqueous solution was discharged from the prepared needle (FIG. 1). At this time, Ultra Dispensing Tips (27G, ID: 0.21 mm) manufactured by EFD were used as the needle attached to the syringe. The discharged 7% by weight collagen aqueous solution was immediately dehydrated and solidified into a yarn shape in an ethanol tank 41 containing 3 L of 99.5 vol% ethanol (Wako Pure Chemicals, special grade). The filamentous collagen pulled up from the ethanol tank 41 is placed in a second ethanol tank 42 containing 39.5 L of ethanol (Wako Pure Chemicals, special grade) and completely separated from the ethanol tank 41 for about 30 seconds at room temperature. Then, it was immersed and further dehydrated and solidified. Subsequently, the filamentous collagen pulled up from the second ethanol tank 42 is passed through a blower / dryer 51 into which dry air is sent for about 3 seconds, and then tensioned by a tension pulley 52 so that the yarn does not loosen. SUS roll-shaped winder 6 having a diameter of 78 mm and a total length of 200 mm was rotated at 35 rpm and wound. When the roll-shaped winder 6 is wound, continuous spinning is performed until the 7 wt% collagen aqueous solution filled in the syringe 3 is exhausted while reciprocating at a speed of 1.5 mm / s in the axial direction of the roll-shaped winder. went. Thus, a bobbin of collagen single yarn 2 was obtained.

Example 2 Thermal Dehydration Crosslinking Treatment of Collagen Single Yarn The collagen single yarn produced in Example 1 was vacuum wound in a vacuum dry oven (in a state of being wound around a stainless steel (SUS) roll-shaped winder 6. A thermal dehydration cross-linking reaction is performed for 24 hours at 135 ° C. under reduced pressure (1 Torr or less) using an oil rotary vacuum pump (ULVAC; GCD135-XA type) using EYELA; VOS-300VD type). A bobbin of applied collagen single yarn was obtained.

Example 3 Crosslinking reaction treatment of collagen single yarn with glutaraldehyde Collagen single yarn was unwound from roll-shaped winder 6 wound with collagen single yarn produced in Example 1, and 0.1 vol% glutaraldehyde It was immersed in a glutaraldehyde solution tank 7 (FIG. 2) filled with the ethanol solution for 6 seconds at room temperature to perform a crosslinking treatment. Thereafter, the collagen single yarn from which the glutaraldehyde solution layer has been removed is immediately immersed in a washing ethanol tank 43 to wash and remove excess glutaraldehyde, and the collagen single yarn from which the washing ethanol tank 43 has been removed is placed around the yarn. The inside of the blower dryer 51 into which the dry air was spirally passed was passed for 3 seconds at room temperature and dried by blowing. Thereafter, the SUS roll-shaped winder 61 having a diameter of 78 mm and a total length of 200 mm was rotated at 35 rpm while being wound up while maintaining the tension with the tension pulley 52 so that the collagen single yarn 2 was not loosened. In this manner, a bobbin of collagen single yarn subjected to glutaraldehyde crosslinking was obtained.

Experimental Example 1 Breaking Strength Test A test collagen single yarn was produced under the conditions of Example 2, and the breaking strength of the collagen single yarn was measured by the following method.
A collagen single yarn is cut into a length of about 10 cm, tapes 81 and 82 are attached to both end points of the cut collagen single yarn 2, and a punch hole 811 is made in one. The hook 831 of the force gauge 83 was hooked into the hole, and the thread was pulled upward (FIG. 3). At this time, the force gauge 83 was fixed to the table, and the indicated value when the collagen single yarn 2 was torn was measured as the breaking strength. When discharging the aqueous collagen solution, the needle gauge used was 27 gauge and 30 gauge, and the concentration of the discharged aqueous collagen solution was 7% by weight. The obtained results are shown in Tables 1 and 2.

Example 4 Production of Culture Substrate A collagen tubular body having a diameter of 1 mm and a thickness of 0.5 mm was obtained by winding the collagen single yarn subjected to thermal dehydration crosslinking obtained in Example 2 around a metal core rod. Produced. A tubular three-dimensional culture substrate made entirely of collagen was prepared, and human chondrocytes and human fibroblasts were cultured. FIG. 4 shows the state of cell substrate engraftment and proliferation. The substrate engraftment and proliferation of each cell immediately after the start of human fibroblast culture (FIG. 4 (a)) and immediately after the start of human chondrocyte culture (FIG. 4 (b)) are shown.

  Good engraftment and proliferation of each cell could be confirmed on the collagen thread running in the form of stripes vertically and horizontally. From this, it was found that the collagen yarn according to the present invention has a sufficient function as a culture substrate.

Example 5 Production of Culture Substrate A tubular three-dimensional culture substrate was produced in the same manner as in Example 4 using the collagen monofilament subjected to the glutaraldehyde crosslinking treatment obtained in Example 3, and human fibers Blast cell culture experiments were performed. FIG. 10 shows the state of cell substrate engraftment and proliferation 14 days after the start of culture. FIG. 5 (a) shows a culture substrate made of collagen single yarn crosslinked at a glutaraldehyde concentration of 0.1% by volume, and FIG. 5 shows a culture substrate made of collagen single yarn crosslinked at a glutaraldehyde concentration of 0.5%. (B).

  Good engraftment and proliferation of cells could be confirmed in collagen filaments that run vertically and horizontally on the muscle. From this, it was found that the collagen yarn according to the present invention has a sufficient function as a culture substrate.

Example 6 Rabbit Implantation Test (1) A rabbit implant specimen (collagen cylinder) was prepared according to the following method.
(A) Thermally dehydrated cross-linked collagen single yarn obtained in Example 2, (b) 0.1% by volume glutaraldehyde cross-linked collagen single yarn prepared in Example 3, (c) the same as in Example 3 Each of the 0.5 vol% glutaraldehyde cross-linked collagen single yarns produced by the above method was wound around a metal core rod, and 3 cylindrical implant specimens made of collagen having an inner diameter of 2 to 3 mm and a total length of about 10 mm were obtained. Kinds were made. About the implantation test piece using 0.1 vol% glutaraldehyde cross-linked collagen thread, after forming the implantation test piece, vacuum dry oven (manufactured by EYELA; VOS-300VD type) and oil rotary vacuum pump (manufactured by ULVAC) GCD135-XA type) was subjected to thermal dehydration crosslinking reaction at 135 ° C. under reduced pressure (1 Torr or less) for 24 hours.

(2) Gamma-ray sterilization (25 kGy) was performed on the prepared collagen implantation test piece, and an implantation experiment was performed according to the following procedure.
Each of the three types of collagen-implanted test specimens was implanted in three rabbit (two total) back muscles, and a polytetrafluoroethylene (ePTFE) sheet (thickness 0.1 mm) of the same size as a control specimen in one place. ) (Trade name: Gore-Tex Patch, manufactured by Goretex) was rolled into a cylindrical shape and embedded. For thermal dehydration cross-linked samples 2 weeks and 4 weeks after implantation, glutaraldehyde 0.1 volume% cross-linked + heat dehydrated cross-linked samples 2 weeks after implantation, and also for glutaraldehyde 0.5 vol% cross-linked samples Two weeks later, for Gore-Tex patches, biopsies were collected 4 weeks after implantation and subjected to HE staining for histological evaluation. 6 and 7 show photographs of the stained images. 6 (a1) shows two weeks after thermal dehydration cross-linking sample, (a2) shows four weeks after thermal dehydration cross-linking sample, FIG. 7 (b) shows glutaraldehyde 0.1 vol% cross-linking + heat dehydration cross-linking sample, and (c) shows Glutaraldehyde 0.5 volume% crosslinked, (d) is a Gore-Tex patch.

  As a result of the implantation experiment, all of the implantation specimens (a) to (c) showed no particularly remarkable inflammatory reaction, good cell infiltration, and the degradation of the graft progressed over time. I was able to confirm. On the other hand, no cell infiltration was observed in the control test piece (d), and the state of degradation and absorption could not be confirmed at all. Accordingly, it has been found that any single collagen yarn produced according to the present invention is a biodegradable and absorbable material compared to existing products.

Claims (10)

The collagen solution is dehydrated in a hydrophilic organic solvent with a water content of 50% or less, then dried and solidified with a water content of 10% or less, and then dried under conditions of a relative humidity of 50% or less and a temperature of 42 ° C or less while maintaining tension. A method for producing a medical collagen single yarn characterized by comprising: The method for producing a medical collagen single yarn according to claim 1, wherein the collagen single yarn is further subjected to a crosslinking reaction treatment after drying. The method for producing a medical collagen single yarn according to claim 1, wherein the collagen single yarn is for medical use. The method for producing a medical collagen single yarn according to claim 1, wherein the hydrophilic organic solvent is selected from the group consisting of alcohols and ketones having 1 to 6 carbon atoms, or a mixture of two or more kinds. The method for producing a medical collagen single yarn according to claim 1, wherein the hydrophilic organic solvent is ethanol. 2. The method for producing a medical collagen single yarn according to claim 1, wherein the drying is blown drying. 2. The method for producing a medical collagen single yarn according to claim 1, wherein the drying is performed at a relative humidity of 30% or less. The method for producing a collagen fiber for medical use according to claim 1, wherein the temperature is 10 to 42C. Crosslinking treatment is thermal dehydration treatment and / or glutaraldehyde treatment method for manufacturing a medical collagen single yarn of claim 1, wherein. The method for producing a medical collagen single yarn according to claim 1, wherein the collagen is derived from pigs.

Images