JPH01131666A - Sheet of medical material and treatment of wound with sheet - Google Patents

Abstract

PURPOSE:To provide a sheet of a medical material which is securely adhered to a wound and absorbs an exudate well, by using a fabric and/or non-woven fabric as a constituent of the sheet and by specifying the size and number of pores. CONSTITUTION:Gelatin and/or collagen are mixed with water, kept at a room temperature for 4 hours or longer and then slowly stirred at 30-70 deg.C to be dissolved. The concentration of gelatin and/or collagen in the aqueous solution is preferably 5-35wt.%. A bridging agent, a surfactant or the like is added to the aqueous solution and the solution is then stirred at a high speed for 30 sec-2min. The revolution speed of a stirring wing is preferably 10,000rpm or above. The foamed solution thus prepared is injected into a mold in which a fabric or non-woven fabric is laid, and is then freeze-dried. 50% or more of all the pores in the obtained sheet should be 50-300mum in diameter. Since the sheet obtained can be securely adhered to a wound and absorb an exudate, a large surface of a burn or an abrasion is cured soon with the sheet.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention is a sheet-like medical material made by crosslinking and foaming gelatin and/or collagen, which is reinforced with woven fabric and/or non-woven fabric. Regarding medical materials. The medical material of the present invention is used for applications such as wound surface covering materials.

(Conventional technology and its problems) Gelatin and collagen are materials with excellent biocompatibility, so they can be used as wound covering materials, artificial blood vessels, adhesion prevention membranes,
Hemostatic material 11 It has been used as various medical materials such as artificial ureters.

However, gelatin and collagen have a high solubility in water as they are, and there is a problem that they dissolve in body fluids, blood, exudates, and the like. Furthermore, it is not sufficient in terms of flexibility and strength.

In order to solve these problems, crosslinking using a crosslinking agent and mixing a surfactant and stirring at high speed to foam the foam to form a sponge-like material have been carried out.

However, when attempting to use such medical materials as covering materials for large-area burns and abrasions, various problems have arisen. One such problem is that due to the low adhesion to the wound surface, the medical material falls off from the wound surface before the wound has healed. In addition, there has been a problem that the absorption of exudate from the wound surface is poor, resulting in insufficient healing effects.

(Technical means for solving the problem) The present invention provides: (1) A sheet-like medical material made by adding a crosslinking agent and a surfactant to gelatin and/or collagen and crosslinking and foaming, (a) a woven (b) the number of pores with a diameter of 50 to 300 μm is 50 of the total number of pores;
% or more of the medical material, and (2) a method for treating a wound in which the wound surface is covered with the medical material.

In the medical material of the present invention, if there is no woven fabric or nonwoven fabric, there are problems such as insufficient adhesion to the wound surface and the medical material falling off before the wound has healed.

In addition, when the number of pores with a diameter of 50 to 300 μm is less than 50% of the total number of pores, the adhesion to the wound surface is insufficient and the exudate from the wound surface is not well absorbed, resulting in a poor therapeutic effect. The problem is that it does not increase.

In the present invention, gelatin and collagen that are commonly used for medical purposes can be used as they are or after being modified with pz acid or alkali.

Examples of the material for the woven or nonwoven fabric include, but are not limited to, polyester, polyamide, cellulose, cellulose derivatives, polyvinyl alcohol, and polyacrylonitrile.

As the crosslinking agent, aldehydes, glycidyl ethers, isocyanates, etc. can be used. Examples of aldehydes include formaldehyde, glyoxal, and glutaraldehyde.

Examples of the glycidyl ethers include ethylene propylene diglycidyl ether, glycerol polyglycidyl ether, diglycerol polyglycidyl ether, sorbitol polyglycidyl ether, and ethylene glycol diglycidyl ether. Isocyanates include difunctional ones such as hexamethylene diisocyanate, α-tolidine diisocyanate, tolylene diisocyanate, naphthylene 1,5-diisocyanate, 4,4-diphenylmethane diisocyanate, and triphenylmethane-4,4,4-trisocyanate. Examples include polyfunctional ones such as isocyanates.

The surfactant is coconut oil fatty acid collagen peptide and/or
or a salt thereof is preferable because of its low toxicity and biological irritation.

Next, the method for manufacturing the medical material of the present invention will be explained.

First, gelatin and/or collagen are mixed with water. The concentration of gelatin and/or collagen in the mixture of gelatin and/or collagen with water is preferably 5 to 35% by weight.

When the concentration of gelatin and/or collagen is less than 5% by weight and more than 35% by weight, the diameter is 50-30%.
This is not preferred because it would be difficult to create a medical material in which the number of 0 μm pores is 50% or more of the total number of pores.

After mixing gelatin and/or collagen with water, leave it at room temperature for at least 4 hours at 30-70°C, preferably 30-40°C for gelatin and 20-40°C for collagen.
Stir gently at °C to dissolve gelatin and/or collagen.

Once the gelatin and/or collagen is completely dissolved, the crosslinking agent is added followed by the surfactant.

In order to react the gelatin and/or collagen with the crosslinking agent, it is preferred to stir the mixture at high speed. At this time, the mixture foams due to the action of the added surfactant and becomes a gelatin and/or collagen foam.

Stirring is preferably carried out for 20 seconds to 5 minutes, more preferably 30 seconds to 2 minutes. Also, the rotation speed of the stirring blade is 110.
000 rpm or more is preferable. When the stirring time is less than 20 seconds, the crosslinking reaction does not proceed sufficiently, and the foam is easily dissolved in blood, body fluids, or secretions. For this reason, stable therapeutic effects cannot be maintained, which is undesirable. Stirring time is 5
If the temperature exceeds 10 minutes, the crosslinking reaction will proceed too much and the viscosity of the mixture will become too high, resulting in the resulting medical material becoming too hard, resulting in problems of reduced flexibility and secretion absorbability.

The foamed product prepared as described above is poured into a molding machine lined with a woven or nonwoven fabric and freeze-dried to obtain the medical material of the present invention. This medical material is in the form of a sponge sheet.

It is preferable to use the medical material of the present invention for the treatment of large-area burns, abrasions, and other wounds that are slow to heal (there is a high risk of infection and cause great pain to the patient). When used to treat abrasions, it is appropriate to cover the wound surface with this medical material.

The medical material of the present invention includes fibronectin, lysozyme,
Pladiomycin, gatamycin, polymyxin, urokinase, TPASSOD, etc. can also be used by absorbing or supporting them.

(Effects of the Present Invention) The medical material of the present invention has high adhesion to the wound surface and high absorption of secretions, so when used for large-area burns, abrasions, etc., healing is accelerated. It also has the advantage of causing less pain to the patient because it feels soft when applied to the wound surface.

(Example) 2001 d of distilled water was added to 30.0 g of gelatin and left at room temperature for 6 hours, then heated to 40° C. and stirred to dissolve. Furthermore, 2.4 g of ethylene glycol diglycidyl ether as a cross-agent, and 3.4 g of Yashito fatty acid collagen peptide potassium (40% aqueous solution) as a surfactant.
was added and stirred for 1 minute at a rotation speed of 18,500 rpm. The above foam was poured into an acrylic container whose bottom was lined with 30 meshes of polypropylene mesh and a woven polyester cloth was placed on top of the mesh. Further, it was covered with a polypropylene mesh of 30 meshes, covered with an acrylic plate, and gelatin was applied to a thickness of 0.5 mm by applying pressure. After freeze-drying this foam, take it out from the molding machine, peel off the mesh and yew, and then heat it at 120°C for 2 hours.
Time processed.

The obtained sponge sheet-like medical material has a pore diameter of 50~
The number of pores of 300 μm accounted for 90% of the total number of pores, and the average pore diameter was 150 μm.

Male rat (weighing 300 g)
A burn wound was created by applying a 25-diameter glass rod heated to 80°C to the shaved back of the animal for 10 seconds. After 2 hours, the water bottle was peeled off, the previously prepared medical material was attached, and the healing process was observed.

As a result, the medical material of this example well absorbed exudate from the wound surface and had good adhesion to the wound surface, so almost no scab formation was observed on the wound surface, and after 12 days, The wound has completely healed.

Comparative Example 1 A sponge sheet-shaped medical material was prepared in the same manner as in Example except that 0.8 g of coconut oil collagen peptide potassium (40% aqueous solution) was used and the stirring speed was changed to 500 rpm.

In the obtained medical material, the number of pores with a pore diameter in the range of 50 to 300 μm is 30% of the total number of pores, and the average number of pores is 450.
It was μm.

Animal experiments were conducted in the same manner as in Example 1 using this medical material. The exudate from the wound surface was not well absorbed by the medical material and began to seep out to the outside. Adhesion was also poor, and thin scabs were observed on the wound surface.

Healing took 17 days.

(Comparative Example 2) A medical material was produced in the same manner as in the example except that a polyester woven fabric was not used.

In the obtained medical material, the number of pores with a pore diameter in the range of 50 to 300 μm accounts for 95% of the total number of pores, and the average number of pores is 125.
It was μm.

Using this medical material, animal experiments were conducted according to Examples. Although this medical material well absorbed exudate from the wound surface, its adhesion was somewhat poor and it fell off on the 7th day. Formation of a thin skin was observed on the wound surface, and it took 17 days to heal.

Claims (3)

[Claims] (1) Sheet-like medical materials made by adding crosslinking agents and surfactants to gelatin and/or collagen to crosslink and foam: (a) woven fabrics and/or nonwoven fabrics are embedded inside, or one side and (b) the number of pores with a diameter of 50 to 300 μm is 50 of the total number of pores.
% or more. (2) The medical material according to claim 1, wherein the surfactant is a coconut oil fatty acid collagen peptide and/or a salt thereof. (3) A method for treating a wound by covering the wound surface with the above-mentioned medical material.