JPS58183169A - Absorbable suturing yarn and production thereof - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improved suture made of chitin fibers and a method for producing the same, and more specifically to an absorbable suture made of chitin fibers with improved bioabsorption rate and its manufacturing method. This relates to a manufacturing method.

Chitin is a polysaccharide consisting of poly(N-acetyl-D-glucosamine), a substance widely distributed in nature such as the exoskeleton of A61II, and has one aminoacetyl group in each repeating unit of its molecule. It has many interesting and unique properties. One of these properties is that it undergoes enzymatic decomposition within the body and is absorbed into one tissue.

Taking advantage of this property, it has been proposed to fiberize chitin and use it as an absorbable suture.

Chitin fibers that make up such sutures include:

In terms of flexibility and usability as a suture thread, the thickness is 20d.
Hereinafter, it is particularly desirable that the dry strength is 0.5 to 5 d, and the dry strength is 29/d or more, particularly 3 f/(1 or more).

The present inventor has found that by relaxing the yarn immediately after wet spinning in #
It was discovered that chitin fibers with small 〃 can be obtained and that absorbable sutures with excellent mechanical properties can be obtained by processing these fibers.
No. 152568, No. 55-164268 This absorbable suture made of chitin fibers is strong enough to withstand practical use during one surgical operation, but it absorbs too quickly when used in a living body, so it can only be used for a short period of time. There is a barrier in which the strength decreases in between.

Generally, absorbable sutures are sufficiently strong for up to 10 to 15 days after use, when healing is well underway.

Although it is preferable that the absorbable suture has the property of being absorbed as soon as possible thereafter, the absorbable suture described above is not an ideal absorbable suture in this respect.

The present inventors have discovered that absorbable sutures made of chitin fibers maintain a strength close to that of surgery during the initial period of use, up to 10 to 15 days after surgery, and after that period, they do not become in vivo. As a result of intensive research to provide sutures that are rapidly absorbed, it was discovered that coating sutures made of chitin fibers with chitin has the effect of suppressing the bioabsorption rate in the early stages after surgery. 1. The ICM of the present invention was achieved. It is.

That is, the present invention provides an absorbable suture made of chitin fibers, the surface of which is coated with chitin, and an absorbable suture with improved bioabsorption rate, and an absorbable suture made of chitin fibers. Improvement in bioabsorption rate characterized by coating the surface of the suture with chitin by applying a chitin solution to the surface of the suture and then coagulating the chitin solution applied to the surface of the suture with a coagulation solution. This is a method for producing absorbable sutures.

The chitin that covers the surface of the suture is the same as the chitin that makes up the m-covered suture, but by providing a coating layer of chitin on the surface of the 5W1 suture, the initial stage of absorbable suture made of chitin fibers is reduced. It is remarkable that a suture can be obtained which has an ideal bioabsorption rate as an absorbable suture.

In the present invention, the chitin that covers the surface of the suture thread and the chitin that constitutes the chitin fibers include not only chitin itself but also chitin derivatives.

Such chitin can be produced by acid treatment of the exoskeleton of crustaceans, insects, etc., and separation and purification of protein and calcium components using caustic soda.

Examples of chitin derivatives include engineered chitins such as methylated chitin and hydroquine-ethylated chitin, and esterified chitins such as acetylated chitin and sulfonated chitin.

Examples of esterified products include formic acid, acetic acid, and butyric acid.

Valeric acid, isobutyric acid, isovaleric acid, benzoic acid, cinnamic acid,
t-rich acid, anthophenic acid, lid! Carboxylic acids such as acids, sulfuric acid, and tonic acids.

Examples include sulfonic acids such as A'7anilic acid, carbonates, and esters of their anhydrides.

The chitin fibers constituting the absorbable suture of the present invention can be prepared from chitin as described above by known methods. to a solvent for chitin, such as a mixture of hydrogen, a mixture of dimethylacetamide and lithium chloride, or a mixture of N-methylpyrrolidone and lithium chloride.

It can be prepared by dissolving chitin to obtain a chitin solution and wet spinning this chitin solution. Preferable chitin fibers have a single yarn denier of 0.5 to 20 d and a dry strength of 2 g/d or more, more preferably 5 f/d.
d or more, particularly preferably 4 f/d or more. And those having a total density of 20 to 200 d are preferably used. Such chitin fibers are passed through a doped nozzle μ and 1c4qI is extracted into a coagulation bath.

By taking it off, a thread containing the solvent is formed.

It can be prepared by treating the formed yarn with a coagulating liquid in a state where substantially no tension is applied to the yarn.

The method for preparing a suture thread from chitin fibers is not particularly limited, and various known methods can be employed. For example, it can be prepared by braiding or twisting approximately 8 to 20 chitin fibers having a total density of 20 to 200 d as described above. As a suture, A described on page 759 of the United States Pharmacopoeia (USP) XX is used.
haortnble surgical・auturc
USP Nize No. 9-0 to No. 4 in Table 1 and UPS in Table 2
Thicknesses of sizes 12-0 to 5 are preferably used, but are not limited thereto.

Various methods can be employed to tI411 the absorbable suture of the present invention whose surface is coated with chitin, but a particularly preferred method considering the flexibility and usability of the resulting suture is as follows: This method coats the surface of the suture with chitin by applying 1 cif tin solution to the surface of the suture, and then coagulating the chitin solution applied to the surface of the suture with a coagulation solution. As the chitin solution, various solutions similar to those used for preparing chitin fibers can be used. The type of chitin does not necessarily have to be the same as the chitin fibers that make up the suture.

The concentration of chitin in the chitin solution is preferably about 0.1 to 5 weight 96, although the method of Hashira can be used to apply the chitin solution to the surface of the suture thread.

For example, there are methods such as immersing the suture in a chitin solution and then removing it, and applying or spraying the suture with a chitin solution. The coagulating liquid may be appropriately selected from known ones depending on the type of solvent used, and water, alcohols/L's, and ethers are particularly preferably used. The coating may be repeated once or twice or more, and the thickness of the coating layer can be adjusted by selecting an appropriate number of times depending on the desired performance. Also.

The thickness of the coating layer can also be adjusted by adjusting the concentration of the chitin solution.

The thickness of the chitin coating is appropriately selected depending on the performance required of the suture, but the coating amount is 0.2% by weight or more, particularly 0.2 to 5 ft 1% of the chitin coating [1 solid matter]. This is preferred, and it is also desirable that substantially the entire surface of the suture thread that comes into contact with body fluids is coated with chitin.

The absorbable suture of the present invention can also be macerated by the following method. For example, a method in which a chitin solution is applied to chitin fibers in the process of nine braids or twisted threads, and then the chitin solution is coagulated with a coagulating solution; A method of coagulating a chitin solution applied to a fiber with a coagulating liquid and then braiding or twisting it, and a method of gathering chitin fibers, applying a chitin solution, and coagulating with a coagulating liquid without braiding or twisting. There are methods such as using sutures.

According to the method of the present invention, the bioabsorption rate of absorbable sutures made of chitin fibers can be easily adjusted. Also 1
According to the method of the present invention, absorbable sutures having various bioabsorption rates can be manufactured from one type of chitin fiber by changing the type of chitin solution.The absorbable suture of the present invention can be used in vivo. , 10-15, which is the initial period of use.
It is ideal as an absorbable suture because it has a higher strength retention rate than conventional sutures for a few days, and is easily absorbed by the living body after that period.

Hereinafter, the present invention will be explained in more detail with reference to Examples.

5! J Example 1 1 red snow (chione Cepaa 0pil)
io-0' fabric) was thoroughly washed with water, thoroughly dried in a 40C hot air dryer, and then subjected to impact-type crushing N (fine micron Victorimy/L/vP-
10) to powder into 100 meshes. This powder 220
919 was treated with 2N-hydrochloric acid (21) for 5 hours in a room @, and this 919 was further treated with 2N-hydrochloric acid (500d) for 2 days. After washing the treated powder with water, 1N of 500111
- Treated with sodium chloride at 100° C. for 12 hours, then washed with water and dried. The obtained chitin was further treated with IN-hydrochloric acid at 40° C. for 1 hour to adjust the molecular weight.

This chitin was dissolved in a dimethylacetamide solution containing lithium chloride [dimethylacetamide: #1 lithium chloride = 20
:1 (weight ratio)] at room temperature so that the chitin concentration is 6 wt%. After 11 years, defoaming was performed to obtain a transparent and active dope.

Put this dope into a tank and pump it with a gear bonder.
0.08W summer, discharged from a 50 hole nozzle into isobutanol, solidified in isobutanol, and then
Winding at a speed of 10 m/win, total denny! is 6
A fiber of 1 d (single yarn Denny ~ L22 d) was obtained.

This chitin II! The dry strength of the drill was 3.819/d. Fifteen of the obtained fibers were taken, and the core part was made of 3 pieces of wood, and m strings were made into 9 braids to obtain a suture thread having a thickness corresponding to 5-(IIc) in Table 1 of USPXX.

On the other hand, the same chitin used in the production of the fibers was dissolved in the same solvent used in the production of the fibers so that the chitin concentration was just over 0.5 wt.

The previously prepared suture was immersed in this solution for 10 minutes at room temperature, taken out, then placed in methanol at room temperature, and coagulated overnight to remove the chitin-coated suture. Obtained. At that time, the weight of the suture increased by more than 0.5 weight, and the outer diameter increased by 596.

After killing this material, it was placed on the back of a rabbit, and the animals were sacrificed over time, and changes in the strength of the threads up to 508 were measured.

For comparison, a Ktl-inclusive test was conducted in the same manner as in 4b for sutures that were not coated with chitin. The results are shown in Table 1.

! ! 1 Compared to Comparative Example 1, Example 1 had a higher strength retention rate for <Ic 10 to 15 days, and was preferable as an absorbable suture thread. Although the mechanism by which the initial strength retention rate of Example 1 is high is not clear, Table 1if of the suture
It is speculated that this is because the presence of the #c coating layer prevents biological fluid from penetrating into the suture thread 11, and as a result, contact between the biological fluid and the chitin fibers is prevented.

In addition, 4J! j of the suture in Example 1! f') There was almost no difference in ease of handling and suturing properties compared to those of Comparative Example 1, and the properties were extremely good.

Patent applicant: Unitika Co., Ltd.

Claims (2)

[Claims] (1) An absorbable suture made of chitin fibers with improved bioabsorption rate, characterized in that the surface of the suture is coated with chitin. (2) Applying a chitin solution to the surface of an absorbable suture made of chitin fibers, and then coagulating the chitin solution applied to the surface of the suture with a coagulation solution to coat the surface of the suture with chitin. A method for producing an absorbable suture with improved bioabsorption rate.