KR100722293B1 - Preparation of chito foam dressing for wound repair - Google Patents

Abstract

The present invention relates to a method for producing a chitosan foam dressing material having the effects of wound healing, sterilization, prevention of scar tissue, suppression of scar tissue, wound recovery and the like against burns, trauma, wounds, bedsores and skin diseases.

In the chitosan foam dressing material according to the present invention, no residual acid remains in the manufacturing process, so that the wound healing force is remarkably improved, and unwanted fusion of the wound tissue and the adjacent or surrounding tissues associated with the wound healing can be prevented as much as possible.

Chitosan, Foam Dressing, Wound Healing

Description

Manufacturing method of chitosan foam dressing material {Preparation of chito foam dressing for wound repair}

The present invention relates to a manufacturing method of chitosan foam dressing material, in order to have the effects of wound healing, sterilization, prevention of scar tissue, suppression of scar tissue, wound recovery, etc. for burns, trauma, wounds, bedsores and skin diseases. The present invention relates to a method for preparing chitosan foam dressing material, which is capable of significantly improving wound healing, leaving no residual acid in the preparation, and preventing unwanted fusion of wound tissue and adjacent or surrounding tissues related to wound healing.
Skin is an important organ that occupies the largest area of our body, protecting it from various harmful environments such as microorganisms, ultraviolet rays, and chemicals, and preventing dehydration and regulating body temperature by suppressing water evaporation. F. Be strong in physical stimuli, be elastic, and fully play its role while the human body is sustaining life.
On the other hand, the skin damage is often caused by a variety of causes, such as severe burns, trauma, wounds, bedsores and skin diseases, such as wounds that are not primary suture may leave severe defects inevitable skin transplantation.
Repair of damaged skin tissue is a very important problem and wound healing with appropriate dressing is essential to speed up the healing of wounds and minimize secondary side effects.
On the other hand, chitosan is a kind of polysaccharide that exists in nature. It is a compound obtained by deacetylating chitin contained in the cell walls of microorganisms such as crab, shrimp shell, squid bone, mold and bacteria. It is used in industry. In the past, chitosan was mainly used in the field of wastewater treatment such as flocculants, heavy metal adsorbents, dye wastewater purification agents, and agricultural fields such as soil modifiers, insecticides, plant antiviral agents, and pesticides. The range of food and beverage applications, health and hygiene applications, cosmetic applications, textile-related applications, and pharmaceutical applications is expanding. In particular, the use of chitosan in wound healing agents, artificial skin, embolic materials, blood coagulants, artificial kidney membranes, biodegradable surgical sutures, and antimicrobial materials has been reported since the 1990s.
Korean Unexamined Patent Publication No. 95-18057 describes the preparation of chitosan for in vivo clinical medicine from shrimp shells. Korean Patent Laid-Open Publication No. 91-19731 describes a method for preparing chilin and chitosan for bioclinical use. Japanese Laid-Open Patent Publication No. 56-68200 describes a method of dissociating flake chitin in water with a mixer or the like to prepare a colloidal dispersion, and producing the paper using the chitin dispersion alone. Korean Patent Application Laid-Open No. 98-76411 discloses a wound using gauze prepared by dissolving chitosan, chitin, oligomers thereof or oligosaccharides thereof in a suitable solvent at 0.1 to 3%, immersing in an area, neutralizing, sterile and drying. A method of making a disinfecting plaster is described. Korean Laid-Open Patent Publication No. 98-13801 describes a wound disposable band with a nonwoven fabric impregnated with chitosan.
In addition, a wound coating material related to chitin and chitosan using a nonwoven fabric is used. Due to a problem of the conventional gauze-type dressing material itself, the wound coating material made of chitin and chitosan as a film has no pores. There was a problem that the moisture permeability and the exuding liquid absorption capacity is insufficient, the moisture permeability is low. Therefore, they cannot be used in wounds with a large amount of exudates, and if the water swelling condition persists, the dressing material collapses due to the remaining acid, causing the infection of the normal skin and causing a greater adverse effect on the wound.
In order to solve this problem, Japanese Patent Laid-Open Publication No. 2003-292501, Japanese Patent Registration 10-502665, Korean Utility Model Registration 20-0340228 and the like have the above-mentioned dressing material in an ethanol aqueous solution (ie, a mixture of water and ethanol) or water or a buffer solution. It proposes a process to neutralize and wash with a buffer. However, this method has the disadvantage that the form of the dressing material may be distorted or deformed during the treatment, and the residual acid cannot be completely removed.

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The present invention remains in the production of chitosan foam dressing material for the effect of wound healing, sterilization, scar tissue prevention, scar tissue suppression, wound recovery, etc. in the treatment of physical trauma including skin damage, surgery and burns, It aims to develop a method that can dramatically improve wound healing without any acid and prevent the unwanted fusion of wound tissue and adjacent or neighboring tissues related to wound healing.

In order to achieve the above object, the present invention is to disperse the chitosan in water and then through the carbon dioxide (CO ₂ ) to dissolve the chitosan to prepare a chitosan aqueous solution, and then mixed with polyethylene glycol, polypropylene glycol, glycerin and the like By freeze-drying this solution, carbon dioxide is removed in the chitosan aqueous solution manufacturing process, and the removal process of a residual acid is unnecessary, and it is related with manufacture of the chitosan home dressing in which no salt remains.

Examples of chitosan used in the present invention include the treatment of α-chitosan or cuttlefish bone obtained by deacetylating chitin obtained by heating shrimp shells and crab shells with caustic soda and treating with hydrochloric acid or the like with caustic soda and hydrochloric acid. The prepared β-chitosan can be used. The chitosan used for this invention can use the thing whose deacetylation degree is 50% or more, and molecular weight 10,000-3,000,000 or so. The concentration of the chitosan aqueous solution is used 0.1 to 20% by weight, preferably 0.5 to 5% by weight. In addition, since the antimicrobial activity and wound healing characteristics of chitosan may vary depending on the molecular weight of chitosan, the low molecular weight chitosan (molecular weight 10,000 to 100,000) and the polymer chitosan may be mixed in consideration of the strength of the dressing material.

In order to prepare the form of the foam dressing of the present invention, that is, the porous sponge form, water-soluble materials such as polyvinyl alcohol, polyvinylpyrrolidone, and the like may be used. These can use 0.5-30 weight% with respect to the whole solution, and it is preferable to use 1-5 weight%.

Glycerol is essentially added to the chitosan solution, preferably 1 to 30% by weight based on the total solution. When added in less than 1% by weight it is difficult to expect the formation of fine pores and increase the tensile strength and elongation, and when it exceeds 30% by weight, the concentration of glycerol is too high to form chitosan foam dressing itself.

In addition, PEG (polyethylene glycol) may be additionally added, and PEG is preferably added at 0.5 to 10% by weight in the total solution, and the molecular weight of PEG used is preferably between 200 and 20,000.

The prepared chitosan solution is placed in a dish of a predetermined shape and size, and freeze-dried to prepare a sponge-like structure in which pores of a predetermined size are formed.

In addition, in order to reinforce the strength of the foam dressing, it is preferable to use a reinforcing material which serves to protect the foam dressing during the wearing period. As such a reinforcing material, for example, polyurethane, polyethylene, polyvinylidene chloride (PVDC), aluminum foil, or the like is appropriately selected, and it is preferable to use it by adhering to the chitosan foam.
Since the chitosan foam dressing of the present invention is free from impurities such as residual acid and chitosan is not present in the salt state, the tensile strength and elongation rate increase dramatically when wet, and have a uniform micropores, so that the wound covering material containing the same is removed from the body. It is excellent in preventing water leakage, absorption of exudates, and prevention of invasion and infection of bacteria from the outside, as well as smooth air flow, so that wound healing and cell differentiation and growth are advantageous.

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Example 1

5 g of chitosan (molecular weight 150,000) was dispersed in 200 g of water, followed by aeration of carbon dioxide through a nozzle for 3 hours to prepare a chitosan solution, to which 4 g of polyethylene glycol (molecular weight 6000) was added and 2 g of glycerin was added. The slurry solution was poured into a mold having a depth of 3 mm, rapidly cooled to −50 ° C., and lyophilized to prepare a chitosan foam.

Example 2

Chitosan foam was prepared in the same manner as in Example 1 except that 2 g of low molecular weight chitosan (molecular weight 25,000) and 3 g of high molecular weight chitosan (400,000) were dispersed in 200 g of water and the carbon dioxide was aerated for 10 hours through a nozzle.

Example 3

5 g of chitosan (molecular weight 150,000) was dispersed in 200 g of water, followed by aeration of carbon dioxide through a nozzle for 3 hours to prepare a chitosan solution, except that 2 g of polyvinyl alcohol (molecular weight 50,000) was used as in Example 1. Was carried out.

Example 4

In order to improve mechanical strength, an acrylic pressure-sensitive adhesive was applied to the polyurethane film with an adhesive, and the chitosan foam prepared in Example 1 was attached to prepare a chitosan foam dressing material.

Example 5

The same procedure as in Example 4 was carried out except that the chitosan foam prepared in Example 2 was used.

Example 6

When the foams prepared in Examples 1 to 5 were made to have a specimen having a thickness of 2.5 mm and a width of 20 cm 2 to measure the strength with a tissue analyzer, the strength of the Examples 4 and 5 was significantly higher than that of Examples 1 to 3 ( About 3 times).
Example 7 (Wound Healing Experiment)

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 Animals were tested as models to see the wound healing effect of the chitosan foam prepared in Examples 1 and 2. The abdominal wall of the rabbit was made of 12 × 10 mm wounds on the left and right sides, respectively. One side of the suture was closed so that the suture was not exposed in the abdominal cavity while being covered with the chitosan foam and leaving one side as it was.

When the results were observed after 2 weeks and 4 weeks, the shape using the chitosan foam of the present invention was almost maintained, and the scar of the wound was very weak as compared with the case where the chitosan foam was not used.

Example 8 (Wound Healing Experiment)

Experiments were performed in the same manner as in Example 7, using the chitosan foam dressing materials of Examples 4 and 5. As a result, there was no scar by the chitosan foam dressing material, and the scar removal effect was excellent also compared with Example 1, 2.

As a result of using the urethane on the back can be said to be suitable for wound treatment because it can prevent the water evaporation and further improve the physical properties.

According to the manufacturing method of the chitosan foam dressing material according to the present invention, it is not necessary to have a process such as neutralization after manufacturing the chitosan foam, and it is possible to produce pure chitosan foam in which residual acid is not left at all. It is expected to be useful for healing wounds such as burns and wounds and regenerating the skin because it is absorbed properly, has excellent strength, and has antibacterial function.

Claims (4)

 Dispersing chitosan in water and venting carbon dioxide (CO₂) to prepare an aqueous chitosan solution, Mixing at least one of polyethylene glycol, polypropylene glycol and glycerin in the aqueous chitosan solution, mixing at least one of polyvinyl alcohol and polypyrrolidone, and then freeze-drying it to prepare a chitosan foam, and Attaching a reinforcement to the chitosan foam Method for producing a chitosan foam dressing material characterized in that it comprises a. The method of claim 1, The molecular weight of the chitosan is in the range of 10,000 to 3,000,000, A method for producing a chitosan foam dressing material, comprising using chitosan alone in the above range, or by mixing a low molecular weight chitosan having a molecular weight of 10,000 to 100,000 and a higher molecular weight chitosan. The method of claim 1, Method of the chitosan solution, characterized in that the concentration of the chitosan solution is 0.1 to 20% by weight. The method of claim 1, The reinforcing agent for reinforcing the strength of the chitosan foam is a method for producing a chitosan foam dressing material, characterized in that polyurethane, polyethylene, polyvinylidene chloride (PVDC) or aluminum foil.