JPH06181978A - Surgical filament - Google Patents

Abstract

PURPOSE:To improve the surface sliding characteristics of a surgical filament such as an operating suture and a ligating filament by coating the surface thereof with a composition containing at least one type of polyvalent metallic salts of acylation amino acid expressed by the specific formula. CONSTITUTION:This surgical filament with improved surface sliding characteristics has a surface coated with a composition containing at least one type of polyvalent metallic salts of acylation amino acid expressed by the general formula. In the formula, R stands for an alkyl group, alkenyl group or a hydroxyakyl group of a straight or branched chain having 7 to 21 carbon atoms, x for one of integers of 1, 2, 3, 5, 10 or 11, M for a polyvalent metal atom, m for the atomic value of the polyvalent metal, and n for an integer from 1 to 4. This polyvalent metallic salt of acylation amino acid contains 0.1 to 20 pts.wt. of a coat for 100 pts.wt. of the filament. Furthermore, a substance containing biological adsorptive copolymer is used as the composition containing at least one type of such polyvalent metallic salts.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surgical filament such as a surgical suture thread or a knotting thread, which has improved surface slip characteristics such as passage through living tissue and knotting ability.

[0002]

In surgery, various sutures and filaments such as knotting threads are used for suturing, fixing and knotting tissues such as internal organs, skin, muscles, bones, joints and blood vessels. To be done. These surgical filaments are often used in very fine multifilament braided or twisted constructions. Even in the case of monofilaments, the surface of the filaments is often not sufficiently smooth when untreated.

Thus, for example, to prevent damage to the tissue due to non-negligible friction between the filament and the tissue during suturing or tissue fixation, or to slide the suture knot into a desired position. Various coatings are applied to the filaments in order to improve the sliding properties. For example, Japanese Patent Publication No. 60-25974 discloses a synthetic multifilament suture coated with a mixture of a metal salt of a higher fatty acid and an absorbent polymer, and JP-A No. 61-76163. The publication also discloses a surgical filament which is dry coated with a metal salt of a higher fatty acid.

[0004] In use, ie during the surgical procedure, surgical filaments are usually exposed to body fluids one or more times or passed through moist tissue before tying a knot. However, when a bioabsorbable suture is coated with a conventionally known coating agent such as calcium stearate, it has some effect in a dry state, but when it is used in actual surgery, when the thread is wet with body fluid or the like, The surface slip property may be deteriorated, it becomes difficult to slide the knot of the filament down to a desired position, and there is also a problem in terms of biological tissue permeability.

In view of the above situation, the present inventors in the patent application relating to Japanese Patent Application No. 2-314426 at least one of N-long chain monoacyl basic amino acids having an aliphatic acyl group having 6 to 22 carbon atoms. , Or a surgical filament coated with a composition containing at least one of the N-long chain monoacyl basic amino acids.

[0006]

The object of the present invention is to use a specific coating agent other than those mentioned above so that surface slip characteristics such as knotting characteristics when wet are substantially the same as those when dry, and An object of the present invention is to provide a surgical filament with high safety for the living body.

[0007]

Means for Solving the Problems As a result of intensive studies on the above problems, the present inventors have found that the surface of a surgical filament is coated with an acylated amino acid polyvalent metal salt for excellent wet knot tying property and The inventors have found that a surgical filament having excellent surface slip properties such as tissue permeability can be obtained, and have reached the present invention.

That is, the present invention provides a surgical filament having improved surface sliding characteristics, wherein the surface of the surgical filament has the general formula (1)

[0009]

[Chemical 2] (In the formula, R is a linear or branched alkyl group having 7 to 21 carbon atoms, an alkenyl group or a hydroxyalkyl group, x
Is an integer of 1, 2, 3, 5, 10, or 11,
M is a polyvalent metal atom, m is a valence of the polyvalent metal, and n is 1 to 4
Of the acylated amino acid polyvalent metal salt represented by the formula (1) or a composition containing at least one of the acylated amino acid polyvalent metal salt. It is a filament.

The present invention will be described in detail below. The surgical filaments of the present invention may be bioabsorbable or non-absorbable surgical filaments. Further, it may have a monofilament structure or an ultrafine multifilament braid structure. Of these, preferred surgical filaments are bioabsorbable surgical filaments, and in particular, in the bioabsorbable surgical filaments having a multi-filament braided structure, the effect of improving the surface slip characteristics is great.

Examples of the bioabsorbable filaments include, for example, conventionally known natural gut (cut gut), collagen and chitin, synthetic glycolide polymer (polyglycolic acid), lactide polymer (polylactic acid). , Or glycolide-lactide copolymer, glycolide-caprolactone copolymer, polyhydroxybutyric acid,
Examples thereof include poly-p-dioxanone and trimethylene carbonate polymer.

Among these polymers, a glycolide polymer, a lactide polymer, or a glycolide-lactide copolymer is preferable from the viewpoints of the effect of improving the surface sliding property by coating, the strength of the filament and the hydrolyzability.

In the formula (1) [Chemical Formula 2], the alkyl group, alkenyl group or hydroxyalkenyl group represented by R particularly has a carbon number of 7 to 21, and the coating property on the surgical filament is good. is there. When the number of carbon atoms is less than 7, the hydrophilicity of the acylated amino acid polyvalent metal salt is too high to show a good coating effect. Also,
Even if the carbon number is 22 or more, a good coating effect cannot be expected.

Therefore, examples of the linear or branched alkyl group having 7 to 21 carbon atoms used in the present invention include heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group. Group, pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, eicosyl group, henicosyl group and the like.

Examples of the alkenyl group include 2-heptenyl group, 2-octene-8-ynyl group, 3,4-dipropyl-1,3-hexadiene-5-ynyl group and 5,5-
Dimethyl-1-hexyl group, 4-vinyl-1-heptene-5-ynyl group, 5- (3-pentenyl) -3,6,8
-Decatriene-1-ynyl group, 6- (1,3-pentadienyl) -2,4,7-dodecatriene-9-ynyl group, 2-nonyl-2-butenyl group and the like can be mentioned.

Examples of the hydroxyalkyl group include hydroxyheptyl group, hydroxydecyl group, hydroxytetradecyl group, hydroxynonadecyl group and the like.

In the general formula (1) [Chemical Formula 2], examples of the polyvalent metal atom represented by M include aluminum, calcium, zinc, zirconium, magnesium, iron and titanium.

In the present invention, the acylated amino acid polyvalent metal salt may itself be coated on the filament by itself, or may be used as one component of a coating agent composition comprising a mixture of several components. .

In the present invention, the term "coating" does not necessarily mean that the entire filament is completely covered, but the coating agent is sparsely or mottled partially coated or adhered on the surface of the filament. May be.

The acylated amino acid polyvalent metal salt used in the present invention can be produced, for example, in the same manner as a usual metal soap synthesis method.

That is, for example, general formula (2)

[0022]

[Chemical 3] (In the formula, R is a linear or branched alkyl group having 7 to 21 carbon atoms, an alkenyl group or a hydroxyalkyl group, x
Is a soluble metal salt of an acylated amino acid represented by any one of 1, 2, 3, 5, 10 and 11) (for example, sodium salt) is dissolved in water, It is manufactured by adding an aqueous solution of a polyvalent metal salt so that the amount becomes almost equal, performing salt exchange, thoroughly stirring, filtering, washing with water, and then drying.

Examples of the water-soluble polyvalent metal salt used here include aluminum sulfate, aluminum chloride, aluminum nitrate, potassium aluminum sulfate, magnesium chloride, magnesium sulfate, potassium magnesium sulfate, calcium chloride, zinc chloride, zinc nitrate and sulfuric acid. zinc,
Examples thereof include zinc acetate, zirconium sulfate, zirconium chloride, titanium oxysulfate and titanium tetrachloride.

The coating on the surgical filament is
The above-mentioned acylated amino acid polyvalent metal salt may be used alone. In this case, the acylated amino acid polyvalent metal salt may be directly attached to the filament without using a solvent, or may be suspended and dispersed by stirring in a volatile solvent such as chloroform or xylene to obtain a suspension dispersion liquid. Can also be coated by passing the solvent through a filament and then removing the solvent by evaporation.

The acylated amino acid polyvalent metal salt has good adhesiveness to the surface of the surgical filament and can be well coated on its own by itself, so that even a small amount sufficiently improves the sliding property of the filament. be able to.

It is also possible to coat the surgical filaments with the acylated amino acid polyvalent metal salt in the form of a composition consisting of a mixture with other substances. At this time, as the other substance mixed with the acylated amino acid polyvalent metal salt, for example, a biocompatible and thermoplastic or solvent-soluble polymer is preferable.

For example, glycolide polymer, lactide polymer, glycolide-lactide copolymer, polycaprolactone, polyoxyalkylene, polytetrafluoroethylene, silicone resin and the like can be mentioned. Above all,
Biodegradable glycolide polymer, lactide polymer,
Glycolide-lactide copolymers are particularly preferred.

In this case, for example, a melted solution or a dissolved solution of the above polymer is mixed and suspended with an acylated amino acid polyvalent metal salt, and a surgical filament is passed through the suspension for coating and then cooled. Alternatively, it can be carried out by removing the solvent.

In a surgical filament coated with a composition comprising a mixture of an acylated amino acid polyvalent metal salt and the polymer, the polymer not only acts as a binder for the acylated amino acid polyvalent metal salt, The slight but moderate compaction of the surgical filament itself remedies the drawback of being sometimes too pliable and cumbersome, especially when the filament is of a multifilament braided construction.

When a filament is coated with a composition of an acylated amino acid polyvalent metal salt and the above polymer, the amount of the acylated amino acid polyvalent metal salt in the composition is preferably about 20% by weight (composition ratio 1: 4) or more is preferable. It is particularly preferably 50% by weight or more, and further preferably 80% by weight or more. If it is less than 20% by weight, a good coating effect, that is, a good surface sliding property cannot be expected, and it tends to be difficult to smoothly slide down the knot, especially when wet.

In the present invention, other conventionally known lubricants and coating agents such as calcium stearate may be used in combination with the above-mentioned acylated amino acid polyvalent metal salt. In this case, the amount of the acylated amino acid polyvalent metal salt in the coating agent composition is preferably 20% by weight or more.

In the present invention, the amount of the above-mentioned acylated amino acid polyvalent metal salt coated on the surgical filaments directly or as a part of the composition is determined by the structure of the filaments such as the number of filaments or the number of braids or twists. Although it varies depending on the degree of clogging, etc., it is preferably appropriately selected from the range of 0.1 to 20% by weight based on the weight of the surgical filament. When it is less than 0.1% by weight, it is difficult to expect a good coating effect, and when it is 20% by weight or more, powder (coating agent) tends to fall off, which is not preferable because of poor appearance and economical efficiency. More preferably, it is about 0.5 to 10% by weight.

[0033]

EXAMPLES Next, the examples will be described more specifically. The physical property values in the examples were measured by the following methods.

(1) Knotting Test Subjective Method The sliding property of the surgical filament of the present invention, particularly the evaluation of the sliding property (tie-down property) of the knot, is subjectively extremely easy. That is, as shown in FIG. 1, after the rod-shaped body 1 is tightly bound at the upper portion of the surgical filament 2 which has passed through, both ends (2a and 2b) of the surgical filament 2
Pull the knot 3 by pulling in the direction of the arrow. It can be easily judged by its ease of withdrawal. The evaluation criteria are as follows. 0: The knot does not slip at all or the filament breaks. 1: The knot moves only slightly. It takes a lot of power to move. 2: The knot moves while catching. 3: The knot can be easily slid down. 4: The knot slips very smoothly.

Objective Method As shown in FIG. 2, the surgical filament 2 to be tested is wound around a cylindrical sponge 4 having an inner diameter of 40 mm and an outer diameter of 50 mm once and a knot 3 as shown in FIG. did.
Both ends of the surgical filament 2 are fixed to the chucks 5a and 5b of the tensile strength tester, and the speed is 100 mm / min.
Was pulled at. Depending on the surgical filament 2 tested, the knot did not slip resulting in filament 2 breaking. If the knot slips, it was slid 30 mm. The stress detected by the load cell 6 is the surgical filament 2
The maximum and minimum stresses in the middle 10 mm were recorded, ignoring the 10 mm at the beginning and the end of the sliding of the 30 mm that slipped the knot, as it varied depending on the degree of slippage.

Examples 1 to 9 and Comparative Examples 1 to 5 Powders of various coating agents shown in [Table 1] were directly applied to surgical filaments with human fingers, and the surgical filaments were dried with a dry cloth. The excess coating agent was wiped off while rubbing. The surgical filaments having different amounts of coating agent adhered were obtained according to the number of times of wiping with a cloth. The weight of the obtained surgical filament was measured, and the adhesion amount of the coating agent was calculated as a percentage based on the weight of the surgical filament from the difference from the filament weight before coating. Coated surgical filaments or uncoated surgical filaments were subjected to a tie-down test as they were, and the sliding characteristics when dried were evaluated by an objective method. Further, the filament was immersed in distilled water at 37 ° C. for 1 minute, and then a knotting test was conducted in the same manner to evaluate the sliding property when wet by an objective method. The obtained results are shown in [Table 1].

[0037]

[Table 1]

Examples 10 to 26, Comparative Examples 6 to 10 As shown in Table 2, various resins (1 g) were dissolved in a predetermined amount of chloroform, and then powder of N-lauroyl-β-alanine calcime salt was obtained. In the ratio shown in [Table 1],
A coating agent mixed solution was prepared. Then, the solution was stirred to disperse the powder, and the surgical filament was immersed therein for about 10 seconds and then taken out. The solvent was removed by air drying to obtain a coated surgical filament. The weight of the obtained surgical filament was measured, and the adhesion amount of the coating agent was calculated as a percentage based on the weight of the surgical filament from the difference from the filament weight before coating. Dry and wet glide tests were performed by a subjective method. The obtained results are shown in [Table 2].

Example 27 About 1 g of powder of calcium salt of N-lauroyl-β-alanine was added to 10 ml of xylene, and the powder was dispersed by vigorous stirring. The surgical filament was immersed therein for 30 seconds and then taken out, and the solvent was removed by air drying. After the excess coating agent was wiped off with a dry cloth, the coating agent adhesion amount was calculated to be about 3.3% by weight. Examples 11 to 26 for the obtained filaments
Similarly to the above, when the sliding characteristics were evaluated, the knot could be smoothly pulled down both when it was dry and when it was wet. The obtained results are shown in [Table 2].

[0040]

[Table 2]

[0041]

INDUSTRIAL APPLICABILITY The surgical filament coated with the acylated amino acid polyvalent metal salt provided by the present invention does not substantially change to a dry state even when exposed to a body fluid or when passing through a moistened tissue. It can exhibit sliding characteristics. Moreover, the acylated amino acid polyvalent metal salt is extremely safe for the living body, as can be easily inferred from its structure, and it is appropriate to use the substance as a coating agent.

[Brief description of drawings]

FIG. 1 is a diagram showing a knotting method and a pulling direction of a surgical filament to be subjected to a knotting test.

FIG. 2 is a schematic view of an apparatus used for a knotting test.

[Explanation of symbols]

 1 Rod 2 Surgical Filament 2a One End of Surgical Filament 2b One End of Surgical Filament 3 Knot 4 Sponge 5a Tension Tester Chuck 5b Tension Tester Chuck 6 Load Cell 7 Recorder

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shigeru Imuro 2-1, Tangodori, Minami-ku, Aichi Prefecture Nagoya Mitsui Toatsu Chemical Co., Ltd.

Claims (5)

[Claims] 1. A surgical filament having improved surface slip characteristics, wherein the surface of the surgical filament has the general formula (1) [Chemical Formula 1] (In the formula, R is a linear or branched alkyl group having 7 to 21 carbon atoms, an alkenyl group or a hydroxyalkyl group, x
Is an integer of 1, 2, 3, 5, 10, or 11,
M is a polyvalent metal atom, m is a valence of the polyvalent metal, and n is 1 to 4
Of the acylated amino acid polyvalent metal salt represented by the formula (1) or a composition containing at least one of the acylated amino acid polyvalent metal salt. filament. 2. The surgical filament according to claim 1, wherein 100 parts by weight of the surgical filament is coated with 0.1 to 20 parts by weight of the acylated amino acid polyvalent metal salt. 3. The surgical filament according to claim 1, wherein the composition containing at least one kind of the acylated amino acid polyvalent metal salt is a composition containing a bioabsorbable polymer. 4. The bioabsorbable polymer is glycolide and / or
The surgical filament according to claim 3, which is a polymer or copolymer of lactide. 5. The surgical filament is made of a bioabsorbable polymer.
A surgical filament as described.