JPS63115566A - wound dressing - Google Patents

Abstract

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

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a dressing for the purpose of treating burns, external injuries, wounds, etc., and in particular to prevent infection by bacteria on the covering surface and to prevent leakage of body fluids at an early stage. Relating to dressings that indicate treatment.

(Prior Art) A variety of dressings have been developed for use in treating a wide range of skin damage caused by burns, trauma, wounds, etc. These dressings can be broadly classified into the following three types: are categorized. In other words, (1) tissue pieces such as homogeneous split-thickness cortex pieces, heterogeneous skin pieces, and human amniotic membrane; (2) reconstituted biomaterials such as collagen membranes (nonwoven fabrics) and fibrin membranes; (3) silicone membranes and nylon knitted membranes. It is a synthetic polymer material represented by a layered structure.

(Problems to be Solved by the Invention) However, although the tissue piece of (1) is excellent in controlling intemperance and preventing leakage of body fluids, it has a strong immunological rejection reaction and can only be covered for a short period of time. In addition, collagen, which can be stably supplied, is mainly used as the reconstituted biomaterial in (2), but even if the antigenicity can be reduced by enzyme treatment, it is quickly degraded and absorbed in the body, so it does not last long. Furthermore, the synthetic polymer material (3) is non-degradable and absorbable in the living body, so it has low antigenicity (it can be stably supplied and can be sterilized, but it has poor affinity with the living body). It has the disadvantage of being generally low.

In order to improve the drawbacks of these dressings for treating skin defects, the present invention uses polyamino acids with excellent tissue affinity as a microporous membrane layer, thereby improving the absorption of exudate from the wound surface and the formation of M-weave. The core material improves the strength and handling of the dressing, and by impregnating and applying a topical antibacterial agent to the wound side, it effectively prevents infection by bacteria on the wound surface. The present invention relates to a wound dressing material that promotes initial bioadhesion by attaching a scale and a biocompatible material to the wound dressing material and has a treatment promoting effect.

(Means for solving the problem) That is, a core material made of fibers or a metal network is interposed within a microporous membrane layer made of a polyamino acid, and the microporous 1'J! The first invention is a wound dressing formed by impregnating or applying a topical antibacterial agent on at least one layer surface, the wound dressing comprising a microporous membrane layer made of polyamino acids and a network made of fibers or metal within the layer. A wound dressing is formed by impregnating or applying a topical antibacterial agent to at least one layer surface of the microporous membrane layer with a core material interposed therebetween, and further adhering a biocompatible material to the layer surface facing the wound area. 2 invention.

First, the first invention will be explained.

The polyamino acids used in the present invention include the group Pili
Poly-α-amino acids with excellent affinity are preferred, for example,
Poly(T-benzyl-glutamate).

Poly (L-leucine), copoly (L-lysine-L-
leucine), copoly (L-lysine-L-glutamic acid), and the like.

This polyamino acid microporous membrane layer is a sheet-like sponge structure with a thickness of about 1 to 10 nm and has open cells with a pore diameter of 20 μm to 500 μm on the layer surface facing the wound area,
It is preferable that the diameter decreases from the wound side to the other side.

If the pore size is less than 20 μm, tissue penetration and absorption of exudate will be poor, and water vapor permeability, oxygen permeability, etc. will also be poor, which is unfavorable for wound healing.If it is more than 500 μm, adhesion to the wound surface will be poor, Retention of exudate occurs, which is undesirable. Further, if the thickness is outside the above range, penetration into tissue, absorption of exudate, etc. will be poor, or handleability will be poor, which is not preferable. Note that the pore diameter of the surface portion of the microporous membrane layer that is not a wound area is preferably several μm or less in order to prevent bacteria from entering from the outside.

As the core material made of a fiber or metal net, a net made of natural or synthetic fibers or a metal net is used. When covering materials with elasticity,
It is more preferable because it can accommodate the bending of the body and maintains close contact. Such core materials include, for example, polyurethane,
Polyolefin.

A stretchable woven ring made of a mesh made of synthetic fibers such as polyvinyl chloride, polyvinylidene chloride, polyamide, polyester, etc., a mesh made of natural cellulose fibers, a metal mesh made of ultrafine stainless steel filaments, etc. can give. These core materials have functions such as imparting mechanical strength to the present wound dressing material and providing good handling properties even when peeled off after being covered for a certain period of time.

Silver sulfadiazine is also used as a topical antibacterial agent.

Zinc sulfadiazine, cerium sulfadiazine, silver nitrate, gentamicin, and the like are preferably used.

The wound dressing material according to the present invention can be produced by, for example, making a polyamino acid into a solution using a solvent, injecting the solution into a container in which a mesh core material has been stretched to a predetermined height, quenching it, and then freeze-vacuum drying it. A microporous membrane layer of polyamino acid having a core material within the layer is formed by using the method, and then a topical antibacterial agent is suspended on the wound side or the non-wound side of the membrane layer, or on both of these sides. It is formed by impregnating or applying a suspension and freeze-vacuum drying it.

Next, a second invention related to the present invention will be explained. That is, the present invention relates to a wound dressing formed by adhering a biocompatible material to the layer surface on the wound side of the wound dressing obtained according to the first invention.

Biocompatible materials used in the present invention include fibrinogen, albumin, and γ-globulin.

Serum proteins such as fibronectin and collagen.

Examples include gelatin and mucopolysaccharides. Attaching these biocompatible materials has the effect of promoting initial bioadhesion, preventing accumulation of exudate (body fluid, etc.) between the dressing and the wound surface, and promoting treatment.

Further, as a method of attachment, for example, a solution of the biocompatible material is applied to the layer surface of the wound dressing obtained in the first invention that is on the wound side, and the solution is freeze-vacuum-dried to make it adhere. .

Example 1 A liquid was injected into a 15 cm x 15 cm container in which a nylon net had been stretched at a height of about 1 fl from the bottom. After gelation at room temperature, the surface is dried with hot air at about 50°C, then rapidly cooled to -30°C and freeze-vacuum dried to form a microporous membrane layer with a core material interposed within the layer. A topical antibacterial solution containing 50 μl of sulfadiazine suspended in a benzene solution was applied and impregnated onto the surface of the microporous membrane facing the wound area, and the wound dressing material according to the present invention was obtained by freeze-vacuum drying. . The pore diameter on the wound side of this wound dressing is 100 to 200 μm.
The thickness was approximately two fins at the front and back.

Example 2゜A human fibrinogen aqueous solution (: a degree 1 g/a degree 1
0 ml was applied, rapidly cooled at -20°C, freeze-vacuum dried, and irradiated with ultraviolet rays in a sterile room to form a wound dressing according to the present invention.

The evaluation of the present wound dressings obtained in Examples 1 and 2 was as follows: 6-
The experiment was conducted using 8-week-old rats. A full-thickness skin lesion (3 cm x 2.5 cm) was surgically created on one side of the rat's back, this wound dressing was sutured, gentamicin ointment was applied to the surrounding area, telefabat was sutured, and the lesion was bandaged with an elastic band. This wound dressing was applied to a full-thickness defect in the back skin of a rat.

The covering material obtained in Example 2 was adhered with appropriate strength after being lightly compressed for about one minute, and the covering material did not move during suturing. This is thought to be because fibrinogen present in the lower layer of the sponge changed to fibrin on the wound surface and acted as an adhesive. The covering material obtained in Example 1 also adhered under pressure for several minutes and did not move even when sutured. Also, oozing on the wound surface
Sufficient hemostatic effect was obtained even for bleeding to the extent of bleeding.

Such early adhesion and hemostasis are thought to be effective in preventing blood from forming under the dressing. When the state of the tissue was observed after 4 weeks, new tissue rich in capillaries was observed in the lower part of both the corrugated covering materials obtained in Examples 1 and 2.

This wound dressing is used as it is by applying it to the wound surface. Among wounds, when treating superficial first-degree burns, the dressing is removed when the epidermis formation is completed, while when treating deep first-degree burns and second-degree burns, the covering is protected for a certain period of time and then the dressing is removed. When skin grafting is performed, some of the base material of the wound dressing remains in the newly injected tissue, but since it is made of poly-α-amino acids, fibrinogen, collagen, etc., it is decomposed and absorbed within the tissue. Also,
Fibrinogen is a blood clotting protein, and fibrin is formed by the action of thrombin. Fibrin exhibits excellent adhesion and proliferation properties for fibroblasts. Therefore, by impregnating the wound adhesive layer of the dressing with fibrinogen,
When applied, it exhibits a hemostatic effect, as well as excellent bioadhesion and wound treatment effects.

(Effects of the Invention) As explained above, the wound dressing according to the present invention has the following characteristics.

■ A special structured membrane with a continuously changing pore size controls the insensitivity of thin surfaces through the permeation of water vapor and blocks the intrusion of bacteria from the outside.

■ Topical antibacterial agents inhibit the growth of bacteria present on the wound surface.

■ By making the layer in contact with the wound surface porous, it enables strong biological contact and prevents exudate from accumulating.

■ Promote wound healing by using materials with excellent compatibility with living organisms, such as fibrinogen and collagen.

■ By incorporating a core material, the wound surface is covered and protected for a certain period of time, and then peeled off easily. Upon exfoliation, the base material remaining within the regenerated tissue is biodegraded and absorbed.

Claims (2)

[Claims] (1) A core material made of fiber or metal network is interposed within a microporous membrane layer made of polyamino acids, and a topical antibacterial agent is impregnated or coated on at least one surface of the microporous membrane layer. A wound dressing characterized in that it is formed by: (2) A core material made of fiber or metal network is interposed within the microporous membrane layer made of polyamino acids, and at least one surface of the microporous membrane layer is impregnated or coated with a topical antibacterial agent. A wound dressing material characterized in that it is formed by further adhering a biocompatible material to the layer surface facing the wound side.