KR20210070230A - Biodegradable double struructure with radiographic function - Google Patents

Abstract

The present invention relates to a biodegradable double structure comprising: a core portion made of a biodegradable monofilament; and a sheath portion in which biodegradable multifilaments are formed in the form of a braid along the outer circumferential surface of the core portion, wherein at least one of the core portion and the sheath portion includes a radiopaque material.

Description

Biodegradable double structure with radiopaque function {BIODEGRADABLE DOUBLE STRURUCTURE WITH RADIOGRAPHIC FUNCTION}

The present invention relates to a biodegradable double structure with improved radiopacity by applying a braid shape, and specifically, a radiopaque material while having a core part or a sheath part in which the filament is in the form of a braid. It relates to a biodegradable double structure that can accurately determine the position of the double structure inserted into the body through radiation, including

The conventional technology is a technology for injecting the yarn itself in a core-sheath form, mixing and injecting radiopaque particles together in a polymer resin. The melting point of the radiopaque material must be higher than the material to be injected to be stable. There is a limit in that it can exhibit radiopaque properties.

Since it had to be a material with a melting point similar to or higher than that of a biodegradable polymer, the choice of radiopaque material to be input is inevitably narrow. Alternatively, there is also a problem in that it is difficult to uniformly exhibit radiopacity within the biodegradable double structure due to chemical transformation.

The average diameter of the radiopaque material should be smaller than the diameter of the biodegradable yarn, and the radiopacity can be optimized only by inputting a weight in a range that is not excessive.

When the radiopaque material is non-uniformly mixed, radiopacity may also appear non-uniformly, and excessive input of the radiopaque material may reduce the biodegradability and mechanical properties of the biodegradable polymer.

Accordingly, the present inventors have completed the present invention as a result of efforts to solve the above-described problems.

An object of the present invention for solving the above-mentioned problem is to apply a braid shape to the sheath formed along the outer circumferential surface of the core part to minimize material loss that may occur in the manufacturing process while providing a uniform surface on the biodegradable yarn surface. An object of the present invention is to provide a biodegradable double structure capable of imparting radiopacity.

Another object of the present invention is to provide a biodegradable double structure capable of imparting uniform radiopacity without reducing the biodegradability and physical properties of the biodegradable polymer by limiting the average particle diameter and weight range of the radiopaque material.

Another object of the present invention is to configure the biodegradable material of the core part and the sheath part differently, so that there is a difference in the decomposition rate (hydrolysis rate) of the core part and the sheath part, so that the biodegradable double structure can improve performance until the desired decomposition period It is to provide a biodegradable double structure that can be maintained.

In one embodiment of the present invention in order to achieve the above object, a biodegradable dual structure capable of in vivo insertion includes a core portion formed of a biodegradable monofilament; and a sheath in which biodegradable multifilaments are formed in a braid shape along an outer circumferential surface of the core, and at least one of the core and the sheath may include a radiopaque material.

In one embodiment of the present invention, the biodegradable dual structure that can be inserted in vivo includes a core portion formed of a biodegradable multifilament; and a sheath in which biodegradable multifilaments are formed in a braid shape along an outer circumferential surface of the core, and at least one of the core and the sheath may include a radiopaque material.

In one embodiment of the present invention, in the biodegradable dual structure that can be inserted in vivo, the pitch angle in the braid form may be 30° to 90°.

In one embodiment of the present invention, the average diameter of the core portion may be 40 to 80% of the average diameter of the biodegradable double structure.

In one embodiment of the present invention, the average diameter of the filaments constituting the multifilament may be 1 to 20% of the average diameter of the multifilament.

In one embodiment of the present invention, biodegradable dual structures capable of in vivo insertion are gold, silver, platinum, tantalum, tungsten, strontium, iridium, bismuth, bromine, iodine, barium sulfate, barium oxide, bismuth oxide, bismuth trioxide , sodium iodide, iohexol (iohexol), ioversol (ioversol), iobittridol (iobittridol) and may include at least one radiopaque material selected from the group consisting of ytterbium chloride.

In one embodiment of the present invention, the radiopaque material included in the core part or the sheath part may be included in an amount of 10 to 35% by weight based on the biodegradable double structure.

In one embodiment of the present invention, the material of the biodegradable monofilament is poly-L-lactide, poly-D-lactide, poly-D, L-lactide, polyglycolide, polycaprolactone, poly- L-lactide-co-glycolide, poly-D-lactide-co-glycolide, poly-D,L-lactide-co-glycolide, poly-L-lactide-co-caprolactone , poly-D-lactide-co-caprolactone, poly-D,L-lactide-co-caprolactone, polyglycolide-co-caprolactone, polydioxanone, polytrimethylene carbonate, polyglycolide -co-dioxanone, polyamide ester, polypeptide, polyorthoester-based, polymaleic acid, polyphosphazene, polyanhydride, polysebacyanhydride, polyhydroxyalkanoate, polyhydroxybutyrate, polycyano Acrylate, polydopamine, polygluconate, polyhydroxybutyrate, polyanhydride, polyphosphoester, polyalphahydroxy acid, polyethylene glycol, polyvinyl acetate, polyiminocarbonate, polylactic acid, polylactic acid-polyethylene It may be at least one selected from the group consisting of copolymers, polyesteramides, polyglycolic acid, cellulose, cellulose acetate butyrate, cellulose triacetate, modified cellulose, and copolymers thereof.

In one embodiment of the present invention, the material of the biodegradable multifilament is poly-L-lactide, poly-D-lactide, poly-D, L-lactide, polyglycolide, polycaprolactone, poly- L-lactide-co-glycolide, poly-D-lactide-co-glycolide, poly-D,L-lactide-co-glycolide, poly-L-lactide-co-caprolactone , poly-D-lactide-co-caprolactone, poly-D,L-lactide-co-caprolactone, polyglycolide-co-caprolactone, polydioxanone, polytrimethylene carbonate, polyglycolide -co-dioxanone, polyamide ester, polypeptide, polyorthoester-based, polymaleic acid, polyphosphazene, polyanhydride, polysebacyanhydride, polyhydroxyalkanoate, polyhydroxybutyrate, polycyano Acrylate, polydopamine, polygluconate, polyhydroxybutyrate, polyanhydride, polyphosphoester, polyalphahydroxy acid, polyethylene glycol, polyvinyl acetate, polyiminocarbonate, polylactic acid, polylactic acid-polyethylene It may be at least one selected from the group consisting of copolymers, polyesteramides, polyglycolic acid, cellulose, cellulose acetate butyrate, cellulose triacetate, modified cellulose, and copolymers thereof.

In one embodiment of the present invention, the core portion or the sheath portion may further include a polyoxalate copolymer (PVAX).

In one embodiment of the present invention, the polyoxalate copolymer (PVAX) may be included in the biodegradable double structure in an amount of 1 to 20% by weight.

In an embodiment of the present invention, the core part or the sheath part may further include _{magnesium hydroxide (Mg(OH) 2 ).}

In one embodiment of the present invention, the magnesium hydroxide (Mg(OH) ₂ ) may be included in the biodegradable double structure in an amount of 10 to 30% by weight.

In the biodegradable double structure according to the present invention, a radiopaque function can be stably achieved in the biodegradable double structure by applying a braid shape to the sheath formed along the outer circumferential surface of the core part.

In the biodegradable double structure according to the present invention, since the sheath is manufactured in the form of a braid, the material loss that may occur in the manufacturing process is small compared to the double structure manufactured by thermal or chemical bonding, so it is economically excellent.

In addition, since the sheath is manufactured based on the physical bonding in the form of a braid, it does not cause thermal or chemical transformation of the radiopaque material, so that it is possible to impart uniform radiopacity to the surface of the biodegradable yarn.

In addition, in the biodegradable double structure according to the present invention, the biodegradable material of the core part and the sheath part is configured differently, and the decomposition rate (hydrolysis rate) of the core part and the sheath part is designed to be different, so that the biodegradable double structure is the desired decomposition. There is a possible effect to allow the performance to be maintained for a period of time.

1 is a schematic diagram showing a surgical suture according to an embodiment of the present invention.
Figure 2 is a schematic diagram showing a surgical suture corresponding to another embodiment of the present invention.
3 is a schematic diagram showing the structure of a spinning machine for producing a biodegradable monofilament in the present invention.
4 is a schematic diagram showing the structure of a spinning machine for producing a biodegradable multifilament in the present invention.
5 is a schematic diagram of a spinning pack (nozzle pack) used in the present invention.
6 is a schematic view showing a braiding device for forming a braid (braid) form in the present invention.
7 is a schematic diagram showing a biodegradable multifilament form to be implemented in the present invention.
8 is a schematic view showing a cross-section of a biodegradable double structure that can be implemented in the present invention.
9 is a photograph taken of the state of the surface of the biodegradable double structure that can be implemented in the present invention.
10 is a schematic diagram illustrating the concept of a pitch angle in the present invention.
11 is a photograph of a biodegradable double structure in the present invention and a photograph analyzed by X-ray of a portion treated with sodium iodide (NaI) and a portion not treated.

Embodiments of the present invention may be modified in various forms, and the scope of the present invention is not limited to the embodiments described below. The embodiments of the present invention are provided in order to more completely explain the present invention to those of ordinary skill in the art.

The biodegradable dual structure capable of in vivo insertion of the present invention may be a medical article such as a biodegradable polymer stent, a scaffold, or a surgical suture.

The biodegradable double structure capable of in vivo insertion of the present invention may include a core portion and a sheath portion, and although there is no clear limitation on the average diameter of the biodegradable double structure including the core portion and the sheath portion, in the present invention, 100 μm or more can be range.

When the average diameter of the biodegradable double structure is less than 100㎛, it may be difficult to meet the mechanical properties of the biodegradable double structure compared to the diameter.

At least one of the core part and the sheath part of the biodegradable dual structure capable of in vivo insertion of the present invention may include a radiopaque material.

The sheath portion of the biodegradable dual structure capable of in vivo insertion of the present invention is formed in the form of a biodegradable multifilament braid along the outer peripheral surface of the core part.

Since the braid shape of the biodegradable double structure sheath part of the present invention is manufactured based on physical bonding, it does not cause thermal or chemical transformation, so that it is possible to impart uniform radiopacity to the surface of the biodegradable yarn.

In the present invention, the pitch angle is formed in the range of 90° or less as the angle at which the filaments intersect in the braid form of the sheath, and may indicate the degree of fineness of the braid form.

In a process using a braid device, the pitch angle in the braid form can be adjusted according to the angle and speed, and the amount of radiopaque material injected by making the braid form more than one layer can be adjusted.

As the pitch angle becomes narrower, the surface area at which the radiopaque material is absorbed in the braid form of the biodegradable double structure may be improved, and the density of the radioactive material present per unit area may be increased.

However, in the present invention, the pitch angle may be in the range of 30° to 90°, and when it is less than 30°, excessive tensile force is applied between the filaments, and a problem that the filaments may be twisted or broken may occur.

As a result, by producing the sheath portion of the biodegradable multifilament in the form of a braid, even if a small amount of radiopaque material is injected, there is an effect of exhibiting uniform radiopacity with high efficiency in the biodegradable double structure.

The radiopaque material of the present invention is applied only to the sheath portion, and the core portion may be limited to a biodegradable material having a different decomposition rate while not exhibiting radiopacity and excellent biocompatibility.

The biodegradable monofilament or multifilament of the present invention is poly-L-lactide, poly-D-lactide, poly-D, L-lactide, polyglycolide, polycaprolactone, poly-L-lactide- co-glycolide, poly-D-lactide-co-glycolide, poly-D,L-lactide-co-glycolide, poly-L-lactide-co-caprolactone, poly-D- Lactide-co-caprolactone, poly-D,L-lactide-co-caprolactone, polyglycolide-co-caprolactone, polydioxanone, polytrimethylene carbonate, polyglycolide-co-dioxanone , polyamide ester, polypeptide, polyorthoester type, polymaleic acid, polyphosphazene, polyanhydride, polysebacianhydride, polyhydroxyalkanoate, polyhydroxybutyrate, polycyanoacrylate, polydopamine , polygluconate, polyhydroxybutyrate, polyanhydride, polyphosphoester, polyalphahydroxy acid, polyethylene glycol, polyvinyl acetate, polyiminocarbonate, polylactic acid, polylactic acid-polyethylene copolymer, polyester It may include at least one biodegradable polymer selected from the group consisting of amide, polyglycolic acid, cellulose, cellulose acetate butyrate, cellulose triacetate, modified cellulose, and copolymers thereof.

In the present invention, the core part is polylactide-based polymer, polyglycolide-based polymer, poly(α-hydroxy ester), poly(lactic acid), poly(glycolic acid), poly(caprolactone), poly(p-dioxa) Non), poly(trimethylene carbonate), poly(oxaester), poly(oxaamide), poly(lactide)-PLLA, poly(lactide/glycolide), poly(glycolide/caprolactone) (75 /25), poly(glycolide/trimethylene carbonate), polyamino acids derived from tyrosine, poly(DTH carbonate), poly(arylate), poly(imino-carbonate), phosphorus containing polymers, poly(phosphoesters) and Poly(phosphazene), poly(ethylene glycol)-based block copolymer, PEG-PLA, PEG-poly(propylene glycol), PEG-poly(butylene terephthalate), poly(α-malic acid), poly(ester amide) , polyalkanoate, poly(hydroxybutyrate) (HB), poly(hydroxyvalerate) (HV) copolymer, DLPLA; PLA/PGA copolymers (95/5; 85/15); It may be selected from the group consisting of PLA-PCL copolymers, which have a faster absorption time than PLLA, and copolymers and blends thereof.

In the present invention, the cis part is poly(glycolic acid) (PGA), poly(α-hydroxy ester), polyanhydride, poly(carboxyphenoxy hexane-sebacic acid), poly(fumaric acid-sebacic acid), poly(carboxy Phenoxy hexane-sebacic acid), poly (imide-sebacic acid) (50-50), poly (imide-carboxyphenoxy hexane) (33-67), tyrosine-derived polyamino acids, polyorthoesters (diketene acetal) polymers), phosphorus-containing polymers, PGA/PLA (90/10); PGA/PCL (75/25, 50/50, 65/35); poly(p-dioxanone) and their derivatives, poly(ethylene glycol), with a longer absorption time than PGA; citrate esters and other water-soluble materials that dissolve to provide a high surface area for faster absorption, and copolymers and blends thereof.

In another embodiment of the present invention, when the core part is a biodegradable monofilament, the monofilament may be a biodegradable metal yarn, and any one selected from magnesium or a magnesium alloy may be used for the biodegradable metal yarn, but high tensile strength and high tensile strength A magnesium alloy having elongation and high modulus of elasticity is preferably used.

Here, the magnesium alloy may include, but is not limited to, aluminum, zinc, manganese, and the like, and the magnesium alloy is preferably composed of 1 to 5% by weight of aluminum, 0.5 to 2% by weight of zinc, and 93 to 98% by weight of magnesium.

In the present invention, the average diameter of the core part may be 40 to 80% of the average diameter of the biodegradable double structure. When the average diameter of the biodegradable double structure is less than 40%, the elastic recovery force, which is the force to restore the biodegradable double structure to its original shape. There may be a problem that it is difficult to maintain the shape due to this decrease, and if it exceeds 80%, it may cause irregularities on the surface of the sheath part, making it difficult to obtain stable physical properties of the yarn due to cracks, etc. There may be a problem that it is difficult to control the rate of biodegradation have. In this case, the core part may be a monofilament or a multifilament.

When the core part is formed of multifilaments in the present invention, the average diameter of the filaments constituting the multifilaments may be in the range of 1 to 20% compared to the total multifilaments. In case the biodegradable double structure is a cylindrical medical device due to the increase in pores and interfaces, it is difficult to obtain the desired physical properties in relation to the radiation or expansion force, and if it exceeds 20%, it is difficult to obtain the desired properties between the injected radiopaque material and the polymer constituting the filament. There may be a problem that the mechanical properties of the biodegradable double structure may be deteriorated due to the generation of the interface.

In the present invention, in the multifilament formed in the form of a braid in the sheath portion, the average diameter of the filaments constituting the multifilament may be in the range of 1 to 20% compared to the multifilament, and when less than 1%, the number of filaments to be input is If the biodegradable double structure is a cylindrical medical device due to the increase in pores and interfaces, it is difficult to obtain desired properties related to radiation or expansion force. If it exceeds 20%, an interface between the injected radiopaque material and the polymer constituting the filament occurs. As a result, the mechanical properties of the biodegradable double structure may be lowered, which may cause a problem in that it is difficult to control the decomposition rate.

In the biodegradable double structure of the present invention, by configuring the biodegradable material of the core part and the sheath part differently, the decomposition rate (hydrolysis rate) of the core part and the sheath part can be designed to be different.

By designing the core part and the sheath part to have a different decomposition rate as described above, it is possible to maintain the performance of the biodegradable double structure until a desired decomposition period.

In the present invention, the biodegradable polymer of the sheath portion may have a much slower decomposition rate compared to the biodegradable material of the core portion. As a preferred example, a material suitable for the sheath portion may be PLLA, and a material suitable for the core portion may be PGA.

In the present invention, the decomposition rate of the sheath portion is preferably 3 to 48 months, and the decomposition rate of the core portion is preferably 1 day to 3 months.

Since the decomposition of the core proceeds faster than the decomposition of the sheath, partial defects such as cracks occur in the sheath and when the core is exposed, the decomposition of the core proceeds rapidly, and the biodegradable double structure may lose its function due to deterioration of mechanical properties. Problems can arise.

The radiopaque material of the present invention may be coated on at least one of the core part and the sheath part of the biodegradable dual structure that can be inserted into the body to form a layer.

The radiopaque material is a post-process method such as dip-coating, electrospinning, electrospray, and 3D printing. At least one of the core part and the sheath part of the biodegradable double structure. can be coated on

The prior art basically had to inject radiopacity together when the filament was injected, but in the present invention, after the filament is manufactured, radiopacity is given to the monofilament or multifilament of the core part through a post-process, and the multifilament is applied to the sheath part. There is a characteristic that the radiopacity is further improved through a configuration that has a braid shape.

Radiopaque materials usable in the present invention include gold, silver, platinum, tantalum, tungsten, strontium, iridium, bismuth, bromine, iodine, barium sulfate, barium oxide, bismuth oxide, bismuth trioxide, sodium iodide, iohexol ( iohexol), ioversol, iobitridol, and at least one radiopaque material selected from the group consisting of ytterbium chloride.

In the present invention, since the melting point should be considered during the manufacturing process of the yarn of the biodegradable double structure, the radiopaque material of the present invention preferably selects a material having a melting point similar to or higher than that of the material of the sheath part and the core part.

In the present invention, the radiopaque material contains as much as possible a hydrophilic group such as a hydroxyl group (-OH), as the toxicity is lowered, so a hydrophilic material is preferable, and iohexol, ioversol, iobitridol ), such as a hydrophilic iodine-based contrast agent may be preferably used.

In the present invention, by mixing a hydrophilic solvent such as ethanol, water, and methanol with barium sulfate, which is a radiopaque material, the radiopaque material can be applied in the form of a hydrophilic material having low toxicity and high solubility in the body.

In the present invention, the average particle diameter of the radiopaque material should be smaller than the average particle diameter of the biodegradable double structure, and the smaller the average particle diameter, the less the occurrence of the interface between the polymer constituting the filament and the radiopaque material is biodegradable It is possible to prevent deterioration of the mechanical properties of the double structure.

In the present invention, the average particle diameter of the radiopaque material may be in the range of 0.5 to 20 μm. When the average particle diameter of the radiopaque material is less than 0.5 μm, a larger amount of the radiopaque material must be added to indicate opacity and This may cause toxicity and deterioration of properties, and if it exceeds 20 μm, there may be a problem that the mechanical properties of the biodegradable double structure may be lowered due to the generation of an interface between the injected radiopaque material and the polymer constituting the filament. have.

The radiopaque material of the present invention may contain 10 to 35% by weight, preferably 10 to 20% by weight, based on the biodegradable double structure. When included in less than 10% by weight based on the biodegradable double structure, the radiation The impermeability effect may be insignificant, and if it exceeds 35% by weight, the surface of the biodegradable double structure may be irregular and not smooth, making it difficult to insert into the body.

The core or sheath portion of the biodegradable double structure of the present invention may further include a polyoxalate copolymer (PVAX), which effectively removes hydrogen peroxide, a cause of cell damage, and activated macrophages Since it has a function of inhibiting the generation of reactive oxygen species, when a certain amount is injected into the biodegradable double structure, it is possible to inhibit or prevent cell damage to the living tissue near the site where the conduit is inserted.

The polyoxalate copolymer (PVAX) may be formed by copolymerizing vanillyl alcohol and a peroxalate ester.

In the present invention, based on the biodegradable double structure, the polyoxalate copolymer (PVAX) may contain 1 to 20% by weight, and if it is included in less than 1% by weight, there may be a problem with the effect of preventing cell damage, and 20% by weight If it exceeds, there may be a problem of deterioration of the physical properties of the biodegradable double structure due to an increase in pores, etc.

May further comprise a core portion or sheath portion of magnesium hydroxide (Mg (OH) ₂₎ of the biodegradable double structure of the present invention, magnesium hydroxide (Mg (OH) ₂₎ is to neutralize the pH of the tissue around the inserted conduit can play a role

When inflammation occurs due to decomposition of biodegradable double-structured polymers or insertion of external substances, acidic substances are generated and the pH of surrounding tissues is lowered, and the pH is neutralized through chemical reaction of _{magnesium hydroxide (Mg(OH) 2 ), which is a basic component.} It can reduce the inflammatory response of surrounding tissues by more than 90%.

When a functional material such as magnesium hydroxide (Mg(OH) ₂ ) is additionally added, there is an advantage in that the in vivo utility and function of the biodegradable double structure can be maximized.

In the present invention, based on the biodegradable double structure, magnesium hydroxide (Mg(OH) ₂ ) may contain 10 to 30% by weight, but when it is included in an amount of less than 10% by weight based on the biodegradable double structure, the effect of reducing the inflammatory reaction is insufficient. There may be, and if it exceeds 30% by weight, it becomes difficult to impart mechanical strength to the biodegradable double structure, and the dispersibility of the biodegradable resin is greatly reduced or the crystallization of the processed filament is inhibited, so that there may be a problem in that processing becomes difficult. .

Hereinafter, the biodegradable dual structure of the present invention will be described in detail with reference to the accompanying drawings.

1 is a schematic diagram showing a suture for surgery according to an embodiment of the present invention. The suture for surgery is largely divided into a core part 10 and a sheath part 20 .

The surgical suture in Figure 1 is a biodegradable double structure (1) and a core portion (10) made of a biodegradable monofilament; It is made of biodegradable multifilaments, and the outer circumferential surface of the core part 10 is composed of a sheath 20 wrapped in a braid shape, and the sheath 20 may include a radiopaque material. .

2 is a schematic diagram showing a suture for surgery according to another embodiment of the present invention. The suture for surgery is largely divided into a core part 10 and a sheath part 20 .

The surgical suture in FIG. 2 is a biodegradable double structure (1) and a core portion (10) made of a biodegradable multifilament; It is made of biodegradable multifilaments, and the outer circumferential surface of the core part 10 is composed of a sheath 20 wrapped in a braid shape, and the sheath 20 may include a radiopaque material. have.

Hereinafter, in FIGS. 3 to 6, a biodegradable monofilament, a biodegradable multifilament, and a manufacturing process of a biodegradable double structure including the same will be described.

3 shows the structure of the spinning machine 30 for producing the biodegradable monofilament in the present invention, an extruder 31 for melting the polymer, a die head 32 for extracting the extruded polymer in a line form, and Spin pack 33, cooling water 34 for cooling the polymer that has passed through the spin pack 33, and a conventional stretching device 35 for improving the physical properties of the monofilament that has passed through the cooling water 34, and a winder ( 36) is composed.

In the manufacturing process of the biodegradable monofilament, the radiopaque material may be applied. Methods of applying the radiopaque material include methods such as dip-coating, electrospinning, electrospray, and 3D printing, but electrospinning, electric An electrospray method is preferred.

In the dip-coating method, a storage unit (not shown) capable of storing the radiopaque material is disposed around the extruder 31 and the radiopaque material is added in the process of melting the polymer. .

Electrospinning (electrospinning) and electrospray (electrospray) method, by disposing a spray device (not shown) around the stretching device (35) to the biodegradable monofilament emitted from the stretching device (35) The radiopaque material by coating the

Figure 4 shows the structure of the spinning machine 40 for producing the biodegradable multifilament in the present invention.

Looking at this in detail, the composite spinning uses two extruders 41 to melt each polymer. The molten polymer is discharged in a desired amount through the metering pump 42, and by controlling this, it is possible to control the component ratio of each polymer during compound spinning.

The molten polymer discharged through the metering pump 42 is combined and spun into a single yarn 44 through the spinning block 43 as shown in FIGS. 5A and 5B .

Although a single filament is shown for simplicity in FIG. 4 , the spinneret may have any number of outlets, and the compound spun yarn 44 is solidified and crystallized in a cooling bath 45 .

An air gap exists between the spinneret and the cooling tank, preferably 0.5 to 100 cm, and more preferably about 1 to 30 cm.

The solidified yarn 44 is stretched through a conventional stretching device 46 in order to obtain improved physical properties by orientation, and then is wound on a winder 47 .

Optionally, in order to improve the physical properties of the suture, the solidified thread 44 is not directly drawn, but wound up in the form of an undrawn yarn, aged under appropriate conditions, and then stretched through the stretching device 46 to form the drawn yarn. can also be manufactured.

In order to improve the physical properties of the suture during the drawing process, the drawn yarn 44 may be heat treated under appropriate conditions. The solidified yarn 44 or the drawn yarn 44 may be the biodegradable multifilament.

In the manufacturing process of the biodegradable multifilament, the radiopaque material may be applied.

Methods of applying the radiopaque material include methods such as dip-coating, electrospinning, electrospray, and 3D printing, but electrospinning, electric An electrospray method is preferred.

In the dip-coating method, a storage unit (not shown) capable of storing the radiopaque material is disposed around the two extruders 41 inside the emitter to melt the polymer in the process of melting the radiopaque material This is done by adding

Electrospinning (electrospinning) and electrospray (electrospray) method, by disposing a spray device (not shown) around the stretching device (46) to the biodegradable multifilaments emitted from the stretching device (46) The radiopaque material by coating the

5A and 5B show an embodiment of a spinning pack 50 composed of a nozzle and a distribution plate that can be used in the spinning block 43 of the present invention. Each of the first polymer and the second polymer melted through the extruder is Each flows into the nozzle 52 through the distribution plates 51 and 56 to generate the biodegradable multifilament through the nozzle.

Looking at this in detail, FIG. 5A shows a spinning pack for obtaining a sea-island suture 70, in which a second polymer flows through a distribution plate 51 composed of a perforated pin 53 to make the component of FIG. 7A, and the distribution plate 51 ) of the molten first polymer flowing out through the flow path 54 for the component encloses the second polymer. The number of perforated pins 53 of the distribution plate 51 may vary depending on the physical properties of the final filament to be obtained.

If the number of pins is one, a sheath/core type suture 73 as shown in FIG. 7B is obtained.

5B shows a method of making a sheath/core suture 73, in which the second polymer for the core flows through the core pin 57 of the distribution plate 56 in the center, and the first polymer flows around the distribution plate 56. It flows through and has the form of being merged into one strand at the nozzle 52 .

The suture obtained through the manufacturing process as described above uses polymers having different elastic modulus, strength, or melting point, and the like, and thus knot stability, knot strength, and flexibility can be controlled by controlling the component ratio of each polymer.

6 shows a general schematic view of the braiding device 60, the carrier 61 showing the monofilament 62 constituting the core portion 10 and the multifilament 63 constituting the sheath portion 20. After each winding and installation on a bobbin, the core part 10 becomes the center and the sheath part 20 becomes the periphery by wrapping and weaving while supplying in a certain order, so that the structure shown in FIGS. 1 and 2 can be woven. have. It is also possible that the multifilaments 63 constitute the core portion 10 .

7 shows a biodegradable multifilament form that can be implemented in the present invention, and FIG. 7a is an island-in-the-sea filament 70 in the form of a composite spun in the form of a sea-island yarn, in which the island component 71 is surrounded by the sea component 72. Form, FIG. 7b shows a form in which the sheath component 75 surrounds the core component 74 with a sheath-type filament 73 spun in a sheath-core form.

Each of the filaments (70, 73) is different from a typical coating in that the composition and the structure of each of them affect the overall physical properties.

8 shows a cross-section of a biodegradable double structure that can be implemented in the present invention.

Figure 8a is a biodegradable double to form a layer by coating a radiopaque material on the core formed of a monofilament, and then forming a biodegradable multifilament coated with a radiopaque material along its outer peripheral surface in the form of a braid A cross-section of the structure is shown.

Figure 8b is a biodegradable dual structure of forming a core formed of a monofilament not coated with a radiopaque material, and then forming a biodegradable multifilament coated with a radiopaque material along its outer peripheral surface in a braid shape section is shown.

Figure 8c is a biodegradable double forming a layer by coating a radiopaque material on a core formed of multifilaments, and then forming a biodegradable multifilament coated with a radiopaque material along its outer peripheral surface in the form of a braid A cross-section of the structure is shown.

8D is a biodegradable double structure of forming a core formed of multifilaments not coated with a radiopaque material, and then forming biodegradable multifilaments coated with a radiopaque material along the outer circumferential surface thereof in the form of a braid. section is shown.

Figure 9 shows the state of the surface according to the content of the radioactive material, Figure 9a shows a case in which 20% by weight of the radiopaque material compared to the biodegradable double structure is included, and Figure 9b is the radiopaque compared to the biodegradable double structure It shows the case where 35 wt% of the material is included.

As shown in FIG. 9 , when the radiopaque material is excessively included over a certain range, the surface becomes irregular and the problem is not smooth.

10 is a schematic diagram illustrating the concept of a pitch angle in the present invention, FIG. 10a is a case in which the pitch angle is relatively wide, and FIG. 10b is a case in which the pitch angle is relatively narrow. is shown.

Hereinafter, the present invention will be described in detail through Preparation Examples and Test Examples, and the present invention is not limited to these Preparation Examples and Test Examples.

Preparation Example: Preparation of biodegradable dual structures with radiopaque function

1. A monofilament having a diameter of 200 μm constituting the core of a biodegradable double structure with a magnesium alloy containing 3 wt% of aluminum, 1 wt% of zinc, and 96 wt% of magnesium according to a conventional method according to the description of FIGS. 3 to 5 was prepared.

2. Multifilaments composed of PGA fibers having a diameter of 380 μm were prepared according to a conventional method according to the description of FIGS. 3 to 5 .

3. With reference to the solubility of sodium iodide (NaI) in water, 84 g of sodium iodide (NaI) powder and 100 g of distilled water were stirred at 25 °C and dissolved in water to prepare a sodium iodide (NaI) solution.

4. According to the conventional braiding apparatus and method according to FIG. 6, the monofilament prepared in step 1 and the multifilament prepared in step 2 are wound on a carrier or bobbin, respectively, and installed, and then wrapped around the monofilament and weaving. , a core part was formed in the center and a sheath part was formed around the core part to complete a biodegradable double structure.

5. The biodegradable double structure prepared in step 4 was subjected to dip-coating of the sodium iodide (NaI) solution prepared in step 3, and then dried for 24 hours to obtain a biodegradable double structure with radiopacity. completed.

Test Example: Confirmation of radiopaque function

In the preparation example, only a portion of the biodegradable double structure was dip-coated to confirm the radiopacity of the dip-coated portion and the untreated portion through X-ray analysis.

The X-ray analysis result is shown in FIG. 11b, (A) is a part including a metal support, (B) is a part obtained by dip-coating the prepared sodium iodide (NaI) solution, (C) is a prepared part It is a part that has not been subjected to dip-coating of the sodium iodide (NaI) solution.

1: Biodegradable double structure
10: core part
20: sheath
30: spinning machine for producing biodegradable monofilament
31: extruder
32: die head
33: spin pack
34: coolant
35: stretching device
36: winder
40: spinning machine for producing biodegradable multifilaments
41: two extruders
42: metering pump
43: radiation block
44: solidified thread
46: stretching device
50: radiation pack
51: distribution plate
52: nozzle
53: perforated pin
54: flow path for sea components
55: radiation pack body
56: distribution plate
57: core pin
60: braiding device
61: carrier
62: monofilament
63: multifilament
70: sea-island filament
71: island component
72: sea component
73: cis-core filament
74: core component
75: cis component
80a, 80b, 80c, 80d: core
81a, 81b, 81c, 81d: sheath formed in the form of a braid
82a, 82b, 82c, 82d: layer of radiopaque material

Claims (13)

In the biodegradable dual structure that can be inserted in vivo,
A core part formed of a biodegradable monofilament; and
A biodegradable double structure comprising a sheath portion in which biodegradable multifilaments are formed in a braid shape along the outer circumferential surface of the core portion, and at least one of the core portion and the sheath portion includes a radiopaque material. In the biodegradable dual structure that can be inserted in vivo,
A core part formed of a biodegradable multifilament; and
A biodegradable double structure comprising a sheath portion in which biodegradable multifilaments are formed in a braid shape along the outer circumferential surface of the core portion, and at least one of the core portion and the sheath portion includes a radiopaque material. 3. The method of claim 1 or 2,
The pitch angle in the braid (braid) form is a biodegradable double structure, characterized in that 30 ° ~ 90 °. 3. The method of claim 1 or 2,
The average diameter of the core part is a biodegradable double structure, characterized in that 40 to 80% of the average diameter of the biodegradable double structure. 3. The method of claim 1 or 2,
The average diameter of the filaments constituting the multifilaments is a biodegradable double structure, characterized in that 1 to 20% of the average diameter of the multifilaments. 3. The method of claim 1 or 2,
The radiopaque material is gold, silver, platinum, tantalum, tungsten, strontium, iridium, bismuth, bromine, iodine, barium sulfate, barium oxide, bismuth oxide, bismuth trioxide, sodium iodide, iohexol, ioversol (ioversol), iobitridol (iobitridol) and biodegradable double structure, characterized in that at least one selected from the group consisting of ytterbium chloride. 3. The method of claim 1 or 2,
The radiopaque material included in the core part or the sheath part is a biodegradable double structure containing 10 to 35 wt% based on the biodegradable double structure. 3. The method of claim 1 or 2,
The material of the biodegradable monofilament is poly-L-lactide, poly-D-lactide, poly-D, L-lactide, polyglycolide, polycaprolactone, poly-L-lactide-co-gla Ecolloid, poly-D-lactide-co-glycolide, poly-D,L-lactide-co-glycolide, poly-L-lactide-co-caprolactone, poly-D-lactide- co-caprolactone, poly-D, L-lactide-co-caprolactone, polyglycolide-co-caprolactone, polydioxanone, polytrimethylene carbonate, polyglycolide-co-dioxanone, polyamide Esters, polypeptides, polyorthoesters, polymaleic acid, polyphosphazenes, polyanhydrides, polysebacic anhydride, polyhydroxyalkanoate, polyhydroxybutyrate, polycyanoacrylate, polydopamine, polygluco Nate, polyhydroxybutyrate, polyanhydride, polyphosphoester, polyalphahydroxy acid, polyethylene glycol, polyvinyl acetate, polyiminocarbonate, polylactic acid, polylactic acid-polyethylene copolymer, polyesteramide, poly At least one biodegradable double structure selected from the group consisting of glycolic acid, cellulose, cellulose acetate butyrate, cellulose triacetate, modified cellulose, and copolymers thereof. 3. The method of claim 1 or 2,
The material of the biodegradable multifilament is poly-L-lactide, poly-D-lactide, poly-D, L-lactide, polyglycolide, polycaprolactone, poly-L-lactide-co-gla Ecolloid, poly-D-lactide-co-glycolide, poly-D,L-lactide-co-glycolide, poly-L-lactide-co-caprolactone, poly-D-lactide- co-caprolactone, poly-D, L-lactide-co-caprolactone, polyglycolide-co-caprolactone, polydioxanone, polytrimethylene carbonate, polyglycolide-co-dioxanone, polyamide Esters, polypeptides, polyorthoesters, polymaleic acid, polyphosphazenes, polyanhydrides, polysebacic anhydride, polyhydroxyalkanoate, polyhydroxybutyrate, polycyanoacrylate, polydopamine, polygluco Nate, polyhydroxybutyrate, polyanhydride, polyphosphoester, polyalphahydroxy acid, polyethylene glycol, polyvinyl acetate, polyiminocarbonate, polylactic acid, polylactic acid-polyethylene copolymer, polyesteramide, poly At least one biodegradable double structure selected from the group consisting of glycolic acid, cellulose, cellulose acetate butyrate, cellulose triacetate, modified cellulose, and copolymers thereof. 3. The method of claim 1 or 2,
The core part or the sheath part biodegradable double structure further comprising a polyoxalate copolymer (PVAX). 11. The method of claim 10,
The polyoxalate copolymer (PVAX) is a biodegradable double structure containing 1 to 20% by weight based on the biodegradable double structure. 3. The method of claim 1 or 2,
The core part or the sheath part is a biodegradable double structure further comprising _{magnesium hydroxide (Mg(OH) 2 ).} 13. The method of claim 12,
The magnesium hydroxide (Mg(OH) ₂ ) is a biodegradable double structure containing 10 to 30% by weight based on the biodegradable double structure.

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