JP6716841B2 - Hemostatic material - Google Patents

Description

The present invention relates to hemostatic material.

As a mechanism for healing the wound of the skin, (1) When the skin is damaged, platelets are collected in the wound and solidify the blood to stop bleeding. (2) Neutrophils and macrophages are collected around the wound, necrotic tissue and bacteria. It is known to phagocytose and remove (3) fibroblasts gather and shrink the wound, and (4) epidermal cells migrate and gather to epithelize the wound.

In order for the wound to heal, it is necessary for various biological cells to gather and work at the wound in this way. Many cytokines, including growth factors, attract cells to the wound to heal the wound. In order to heal wounds quickly, it is important to maintain an environment in which cells collected in the wound by cytokines can be actively activated.

In the past, the idea was to dry the wound in order to heal the wound, but when the wound dries, living cells die and re-epithelialization is unlikely to occur. In order to solve this problem, in recent years, moist wound healing has rapidly spread, and has been widely clinically applied as one of the methods for wound repair. It is known that in this moisturizing therapy, the wound is healed quickly by keeping the site wet by the exudate generated from the wound site and not drying the wound, because active cell division is performed at the wound (non- Patent Document 1). A wound dressing is a member that provides a moist environment by covering a wounded site and promotes wound healing.

Hydrogels, which are widely used as a component of wound dressings, have no antibacterial or hemostatic properties, and are not decomposed by microorganisms even when buried in soil. For this reason, it will be disposed of by incineration or burial, but there is a possibility that dioxin will be generated if the temperature of the combustion furnace drops during incineration. In addition, it is becoming difficult to secure a place of burial when burying, and there is a demand for products that do not generate dioxin due to incineration and have a low environmental burden.

In addition, many tests and inspections have been carried out in actual medical settings for wound repair materials such as sutures and artificial bones made from chitosan. As a result, hemostatic materials and wound dressings made from chitosan are being developed (Patent Documents 1 and 2). Chitosan has an amino group, and depending on conditions, it is positively charged to aggregate blood cells and exhibit a hemostatic effect. Since chitosan also has an antibacterial effect (Non-patent Documents 2 and 3), it has been considered that chitosan is an ideal component of a hemostatic material and a wound dressing material.

Special table 2011-518592 gazette JP, 2013-133287, A

GEORGIA A. KANNON, ALGIN B. GARRETT, Moist Wound Healingwith Occlusive Dressings, Dermatologic Surgery, Volume 21, Issue 7, p. 583-590, July, 1995. Rejane C. Goy, Douglas de Britto, Odilio B. G. Assist, A review of the antimicrobial activity of chitosan Polymers, vol. 19, no. 3, Sao Carlos, 2009 Tsuimin Tsai, Hsiung-FeiChien, Chitosan Augments Photodynamic Inactivation of Gram-Positive and Gram, Negative Bacteria, Aga. 1883-1890

However, since chitosan is an allergen for crustacean allergies, a person with crustacean allergy may have a serious allergic reaction by using a hemostatic material or a wound dressing made from chitosan. Care should be taken when using chitosan-based formulations for wounds when prescribing to persons with crustacean allergies, and if possible a different formulation should be used. However, there is a potential risk of developing allergies because the person being prescribed may not have previously been aware that they have a crustacean allergy. Also, in order to produce a large amount of chitosan, it is difficult to completely remove endotoxin, which is harmful to the human body and is secreted by bacteria, when the chitosan is isolated because the crab shell that is not aseptic is originally used as a raw material. Is. Known pathological conditions caused by endotoxin include lethal shock, fever, activation of complement, activation of leukocytes, and damage to vascular endothelial cells.

On the other hand, the components of wound dressings that are commonly used other than chitosan, such as hydrogel, do not have antibacterial properties or hemostatic properties. Thus, bacterial growth within the coated interior can impede wound healing and cause serious complications.

The present invention has been made in view of such circumstances, and can be safely used for more people, and suppresses bleeding and infection that prevent healing of wounds, and hemostasis that does not easily cause complications. The purpose is to provide wood .

In order to solve the above-mentioned subject, the 1st mode of the present invention provides a hemostatic material containing cationized cellulose. The reference embodiment of the present invention provides a wound dressing containing as an ingredient a hemostatic material containing cationized cellulose. Also, another reference embodiment of the present invention provides a wound dressing containing cationized cellulose.

Cellulose is a natural compound that plants produce in their bodies by photosynthesis. In recent years, since cellulose can provide an appropriate wound healing environment by absorbing and releasing water, wound dressing materials mainly composed of cellulose such as Dermafill and XCell Cellulose Wound Dressing are commercially available. In addition, wound dressings containing carboxymethyl cellulose, which is a cellulose derivative, have been put to practical use. Unlike chitosan, which causes crustacean allergy, it uses cellulose contained in plants that are ingested daily, and is safer than chitosan from the viewpoint of the possibility of developing allergies. However, although these products have water retention properties, they do not have antibacterial properties or hemostatic properties. Therefore, with a wound dressing material containing cellulose or carboxymethyl cellulose as a main component, complications of internal bacterial growth and bleeding cannot be suppressed when covering the wound.

On the other hand, cationized cellulose has a hemostatic property and an antibacterial property because it has a positively charged functional group unlike cellulose and carboxymethyl cellulose. Hemostasis was examined and confirmed using the activated coagulation time. Regarding antibacterial properties, bacteria that are resident in the skin of medical personnel should be cultured on an agar medium, and a blocking circle should be formed around the filter paper impregnated with gelled cationized cellulose during bacterial culture. It was confirmed that the cationized cellulose has antibacterial properties.

In the present invention, cationized cellulose is contained in the hemostatic material and the wound dressing material that come into direct contact with the wound. This allows the hemostatic material and the wound dressing material to come into direct contact with the bacteria at the wound site, thereby exhibiting antibacterial activity due to the positive charge of the cationized cellulose.

In the present invention, the cationized cellulose has the formula (1):
(In formula (1),
At least one of R ¹ is —R ² —N ⁺ (R ³ )(R ⁴ )(R ⁵ )·X ⁻ ,
Another R ¹ is —H, or —(CH ₂ CH ₂ O) _m —H,
R ² is C _1-6 alkylene, C _2-6 hydroxyalkylene, —(CH ₂ CH ₂ O) ₁ —, or a combination thereof;
l is 1 or 2,
m is 1 or 2,
X ⁻ is an anionic group,
R ³ , R ⁴ , and R ⁵ are C _1-6 alkyl, C _1-6 alkenyl, O—C _1-6 alkyl, C _a Y _b heteroalkyl or heteroalkenyl, and Y is a heteroatom. And when a+b is 4 to 6 and is bonded by a nitrogen atom, a saturated or unsaturated 5-membered ring or 6-membered ring containing the nitrogen atom is formed)
May be

In the present invention, at least one R ¹ is —CH ₂ CH ₂ O—CH ₂ CH(OH)CH ₂ —N ⁺ (R ³ )(R ⁴ )(R ⁵ )·X ⁻ , and R is ³ , R ⁴ and R ⁵ may be a methyl group or an ethyl group. In the present invention, the at least one R ¹ is —CH ₂ CH(OH)CH ₂ N ⁺ (R ³ )(R ⁴ )(R ⁵ )·X ⁻ , and R ³ , R ⁴ , R ⁵ May be a methyl group or an ethyl group. In the present invention, the anionic group may be a halide ion, a phosphoric acid ester group, a carboxyl group, a sulfonic acid group, a sulfuric acid ester group or the like. The halide ion may be fluoride ion, chloride ion, bromide ion, or iodide ion.

With the above structure, cationized cellulose can be obtained more easily.

In the above structure, at least ^one of the other R ¹ may be —(CH ₂ CH ₂ O) _m H.

By setting it as the said structure, the water retention of cationized cellulose can be made higher. As a result, the applicable condition range is expanded, and a wound dressing more suitable for moist treatment can be obtained.

The hemostatic material according to the present invention and the wound dressing material according to the reference embodiment can be safely used by more people and can promote healing of wounds. In addition, compared with the commonly used hydrogel, it works more suppressively against bleeding, infection, etc., so that it is highly safe and the risk of cellulitis, sepsis, etc. can be reduced. Furthermore, compared with chitosan, it is possible to provide a hemostatic material and a wound dressing material that are less likely to cause crustacean allergy.

It is a figure which shows the image of the culture medium which shows the antibacterial property of the cationized cellulose in one Embodiment of this invention. It is a figure which shows the image of another culture medium which shows the antibacterial property of the cationized cellulose in one Embodiment of this invention. It is a figure which shows the image of another culture medium which shows the antibacterial property of the cationized cellulose in one Embodiment of this invention.

Hereinafter, one embodiment of a hemostatic material and a reference embodiment of a wound dressing material according to the present invention will be described. The general formula of cationized cellulose contained in the hemostatic material according to the present embodiment and the wound dressing material according to the reference embodiment is shown below. Any of the hydroxyl groups at the 2-position, 4-position and 6-position of glucose forming cellulose is modified with a cationized functional group.

The cationized cellulose used in the present embodiment can be purchased as a commercial product, or can be synthesized by applying a general synthetic method used for chemical modification of glucan.

(Synthesis example 1)
Synthesis of 2-hydroxy-3-trimethylammoniopropylcellulose chloride In a solution of cellulose (1.0 g) dissolved in 20 mL of 1N sodium hydroxide aqueous solution, 3-chloro-2-hydroxypropyltrimethylammonium chloride (as a cationizing agent ( 2.3 g) is added and the mixture is stirred at 30 to 50°C. The obtained solution is neutralized with 4N acetic acid and then separated with a dialysis membrane using distilled water. The target product can be obtained by freeze-drying the obtained solution.

(Synthesis example 2)
Synthesis of 6-hydroxyethyl-(2-hydroxy-3-trimethylammoniopropyl) cellulose chloride Cellulose (2.0 g) is reacted with ethylene oxide under known conditions to synthesize hydroxyethyl cellulose. Glycidyl trimethyl ammonium chloride (4.5 g) as a cationizing agent is added to a solution of the obtained hydroxyethyl cellulose in 20 mL of a 1N sodium hydroxide aqueous solution, and the mixture is stirred at 30 to 50°C. The obtained solution is neutralized with 4N acetic acid and then separated with a dialysis membrane using distilled water. The target product can be obtained by freeze-drying the obtained solution.

Cationized cellulose having different kinds of substituents can be synthesized in the same manner as in the above-mentioned synthesis example. As the solvent to be used, alcohol such as methanol or ethanol, acetonitrile or the like may be added depending on the solubility of the substrate. The equivalent amount of the cationizing agent to be reacted can be appropriately adjusted depending on the degree of cationization of the desired cationized cellulose.

(Experiment to confirm antibacterial activity of cationized cellulose)
The degree of susceptibility of bacteria to the cationized cellulose according to the present invention was confirmed by the disc method. As one Sunny Foods Petanchek 25 PT4025 standard agar medium was used to culture the bacteria attached to the bare hands of three medical personnel. Bacteria actively forming colonies therein were collected with a sterilized cotton swab, and were evenly applied to three media (medium 1, medium 2, medium 3). As the cationized cellulose, 1 g of hydroxyethyl cellulose hydroxypropyltrimethylammonium chloride ether (Kao Poise C-60H, C-150L) was used, 4 mL of water for injection was added, and the mixture was stirred for 3 minutes. The obtained gelled sample was impregnated in a filter paper and placed on the above medium. After culturing at 37° C. for 48 hours, formation of an inhibition circle was confirmed.

The results of the experiment for confirming the antibacterial activity are shown in FIGS. 1A to 1C. In all of Medium 1 (FIG. 1A), Medium 2 (FIG. 1B) and Medium 3 (FIG. 1C), an inhibition circle was observed around the disk impregnated with the cationized cellulose gel. In each figure, the left side shows the result of using the filter paper impregnated with Poise C-60H and the right side with Poise C-150L, and both groups of Poise C-60H and Poise C-150L show equivalent antibacterial properties. ing. As a result of identification, the bacteria that had grown in the medium were Staphylococcus and Bacillus mixed in Medium 1, Bacillus in Medium 2 and Staphylococcus in Medium 3. From this, it was confirmed that the cationized cellulose had antibacterial activity.

(Confirmation of hemostatic properties of cationized cellulose)
The hemostatic properties of the cationized cellulose according to the present invention were confirmed by using a cartridge for blood coagulation measuring device (JMS Co., Ltd.) and comparing the coagulation time with a control substance. The average weight was determined by measuring 10 diatomaceous earths originally enclosed in a blood coagulation measuring apparatus-dedicated cartridge dedicated to the elapsed time timer "Acttester" (manufactured by Quest Medical Co., Ltd.) for measuring coagulation time. Since the average weight of the diatomaceous earth was 0.015 g in the lot used this time, the cationized cellulose (Kao Poise C-60H, C-150L) having the same weight was replaced. 0.7 mL of whole blood was collected from a subject (inventor this time) using an injection needle having an outer diameter of a needle tube of 0.7 to 1.2 mm (22 to 18 G) and a 1 cc syringe. Immediately after the blood collection, 0.7 mL or less of blood was injected into the cartridge dedicated to the blood coagulation measurement device. Before removing the needle from the cartridge, 0.7 mL of air in the cartridge was extracted. After the blood and the blood coagulation promoter were completely mixed, the cartridge was set in the acttest tube holder of the apparatus main body, and the activated coagulation time was measured.

The measurement results are shown in Table 1. Student's t-test was used for the significance test.
From the above results, it could be confirmed that the cationized cellulose has an action of promoting coagulation and stopping hemostasis. In addition, it was confirmed that cationized cellulose has higher hemostatic properties than chitosan, which is widely used for wound dressings.

The inventor of the present application has found that chemical modification of cellulose with a cationized functional group can provide a hemostatic material and a novel wound dressing material having an antibacterial function and a hemostatic function. The benefits of hemostatic and antibacterial functions on wound healing are described below.

(Hemostasis function)
It is arguable that the wound site must be stopped immediately after injury. At present, as a wound dressing material used when there is bleeding at a wound site, a cartostat (registered trademark) containing alginate and a dressing material containing chitosan are the first choices. However, alginate weak hemostatic function compared to chitosan (Syota Suzuki, Kazuhiko Shibata, Randomized Trial comparing New Chitosan-Based Bandage with Kaltostat Hemostatic Dressing to Control Bleeding from Hemodialysis Puncture Site, Nephrol.Dial.Transplant., 2013,28 (Suppl 1), i226-i239.) and chitosan have low water-retaining ability, and thus they are not sufficient as bases for moisturizing treatment. It is known that the coating material using chitosan provided by Hemcon, Inc. of the United States, when applied to a bleeding site, causes the chitosan to attract the red blood cells and platelets in the blood to quickly block the bleeding site and stop the bleeding. .. Such a function is considered to be due to the positive charge of chitosan under some conditions. Therefore, by using cationized cellulose that is always positively charged without being affected by the pH of the surrounding environment as a component of the coating material used in the early stage of injury, a coating material with higher hemostatic function than chitosan can be obtained. Can be provided.

Also, the risk of bleeding remains after transitioning to moist treatment. If the wound is covered with conventionally used hydrogel, Dioactive (registered trademark), etc., when bleeding during sleep, consciousness disorder, etc., bleeding may not be noticed, and as a result, a large amount of blood may be lost. .. In addition, when a hematoma is formed in a closed and moist environment, since there is no antibacterial activity due to immunity in the hematoma, Staphylococcus aureus and the like are explosively increased in a warm and moisturized hematoma. One staphylococcus divides every 26 minutes and can grow to 2 million Staphylococcus aureus after only 10 hours. This enormous amount of bacterial groups represented by Staphylococcus aureus damages human cell groups gathered for wound healing, and has an adverse effect on wound healing. Therefore, eliminating foreign matter such as hematoma on the wound surface is an important factor for early treatment. In addition, the hemostatic function is an effective additional function in wound healing in order to prevent the formation of hematoma which becomes a medium for foreign substances and bacteria after bleeding.

(Antibacterial function)
Bacteria that have a short cell division time overwhelm living cells at a growth rate and delay wound healing. 2. Description of the Related Art In recent years, a method has been widely used in which a covering material applied to a wound site is frequently replaced and the wound site is washed each time. This is because the dressing keeps the dressing on the wound site and the dressing seals the wound site, thereby creating an appropriate environment for the bacteria existing in the wound site to grow, and rather delays the healing of the wound site. This is because the problem of being lost has become clear.

The hemostatic material according to the present invention and the wound dressing according to the reference embodiment can solve the above-mentioned problems by containing cationized cellulose having a positive charge. On the cell surface of bacteria near neutrality, the phosphate and carboxyl groups dissociate to carry a negative charge. Electrostatically adsorbed to the cell surface of this bacterium, positively charged cationized cellulose, which is present near the surface where the hemostatic material contacts the wound and near the surface of the wound dressing material, enables efficient bacterial adsorption. Can be captured. Furthermore, by incorporating bacteria captured in the surface of the hemostatic material that contacts the wound or near the surface of the wound dressing material into the hemostatic material and the wound dressing material, the bacteria can be removed from the wound site and the wound healing can be accelerated. ..

Therefore, when bleeding occurs at an early stage of injury, it can be used to stop bleeding, and after bleeding, when performing sealing therapy after washing the wound site, it contains a cationized cellulose having an antibacterial action according to the reference embodiment. The use of such a wound dressing can reduce the adverse effects of bacteria as compared with the conventional method in which the wound therapeutic agent having no antibacterial action is continuously applied. In addition, when using a chitosan preparation, it is necessary to be careful if you have a crustacean allergy, but cationized cellulose is less of a concern and can be safely used by more people.

Further, since cationized cellulose has a high water-retaining ability, it gelates by taking in excess water at the wound site. This makes it possible to maintain an ideal environment in which exudate containing various substances important for wound healing can be left on the surface of the wound while suppressing bacterial growth at the wound site for a long time.

Next, embodiments of the hemostatic material and the wound dressing material containing cationized cellulose will be described.

As the hemostatic material in the present embodiment, cationized cellulose can be gelled. This allows the hemostatic material containing cationized cellulose to be applied directly to the wound site. Even irregular wounds can be reliably brought into contact with the wound surface by using this method. Further, the applied gel is covered with gauze, a film or the like and pressed to stop the bleeding. After confirming hemostasis, it is possible to release the pressure and use the wound dressing as it is.

As the wound dressing material in the reference embodiment, cationized cellulose can be used as a sheet-shaped film. Specifically, cationized cellulose can be once dissolved in a solvent such as water or alcohol to form a gel, and the solvent can be forcibly discharged from the gel to form a film. The thickness, density, etc. of this film can be adjusted according to the purpose of use.

The surface of the wound dressing that contacts the wound may be formed into a film by using cationized cellulose alone or a mixture of cationized cellulose and a base. If a water-soluble adhesive is used for the surface that adheres the wound dressing to the skin, the dried skin does not come into contact with the cationized cellulose in the film, while on the wound surface, exudate from the wound. Due to the dissolution of the water-soluble adhesive, the cationized cellulose can be brought into contact with only the wound surface. On the surface opposite to the contact surface, a film that prevents evaporation of water, or a cloth or non-woven fabric that evaporates water appropriately when a large amount of exudate is used, can be used for reinforcement or performance addition. .. By doing this, the formulation with a waterproof film in the dry state and the formulation with a water-permeable sheet when there is a high possibility that exudate is likely to be peeled off due to waterproofing are used properly according to different wounds. A coating material suitable for the above can be prepared.

Further, as the wound dressing material in the reference embodiment, the obtained cationized cellulose can be gelled and contained in the wound dressing material. Cationized cellulose has a higher water retention capacity than chitosan. Therefore, when cationized cellulose is formed into a sheet or gel and applied to the wound site, and a pad having water absorbency is applied on top of it, excess water can be applied to the pad even when a large amount of exudate is generated from the wound site. It is possible to appropriately maintain the moist environment of the wound site as an environment necessary for healing by absorbing the humor.

Further, as described above, cationized cellulose has antibacterial properties. Therefore, even under the condition of directly contacting the wound site as a film or gel, it is possible to maintain an antibacterial environment more suitable for healing until wound healing. A film having air permeability may be used in place of the waterproof film in case of further exudation liquid.

With the shape as described above, the user can easily apply the wound dressing according to the reference embodiment to the wound site. Further, by mixing or adsorbing cationized cellulose with a cloth or a non-woven cloth, it can be used as a hemostatic gauze.

As the wound dressing in the reference embodiment, cationized cellulose is gelled and applied to the wound site, and then the applied part can be covered with a water-permeable or waterproof sheet, if necessary. It may be one. With such a shape, even when the wound site has a complicated shape such as a cut or deep pressure sore, it can be easily applied to the site.

In addition, there are cases in which wounds are accompanied by a large amount of exudate or in which hemostasis is difficult. In order to deal with such a wound, the wound dressing in the reference embodiment can be made into a powder by adding an appropriate base to cationized cellulose or performing a treatment such as spray drying or freeze drying. .. When there is a large amount of bleeding or exudate from the wound site, sprinkle the powder on the wound site to cover it, and then cover it with gauze, a waterproof film, a water absorbent sheet or the like. With such a shape, it is easy to use as a hemostatic material at an early stage of injury, and the wound dressing according to the reference embodiment can be applied to a wound site of various shapes with a high degree of freedom.

According to the present invention , by chemically modifying cellulose with a cationized functional group to give it a positive charge, bacterial growth that hinders wound healing is suppressed, and antibacterial properties are higher than those conventionally used. An excellent hemostatic material and a wound dressing material can be provided.

Moreover, according to the reference embodiment, the use of cationized cellulose having a positive charge can provide a wound dressing having a higher hemostatic effect.

Claims (5)

A hemostatic material containing cationized cellulose for stopping bleeding . The cationized cellulose has the formula (1):
(In formula (1),
At least one of R ¹ is —R ² —N ⁺ (R ³ )(R ⁴ )(R ⁵ )·X ⁻ ,
Another R ¹ is —H, or —(CH ₂ CH ₂ O) _m —H,
R ² is C _1-6 alkylene, C _2-6 hydroxyalkylene, —(CH ₂ CH ₂ O) ₁ —, or a combination thereof;
l is 1 or 2,
m is 1 or 2,
X ⁻ is an anionic group,
R ³ , R ⁴ , and R ⁵ are C _1-6 alkyl, C _1-6 alkenyl, O—C _1-6 alkyl, C _a Y _b heteroalkyl or heteroalkenyl, and Y is a heteroatom. And when a+b is 4 to 6 and is bonded by a nitrogen atom, a saturated or unsaturated 5-membered ring or 6-membered ring containing the nitrogen atom is formed)
The hemostatic material according to claim 1. The at least one R ¹ in the formula (1) is —CH ₂ CH ₂ O—CH ₂ CH(OH)CH ₂ —N ⁺ (R ³ )(R ⁴ )(R ⁵ )·X ⁻ , The hemostatic material according to claim 2, wherein R ³ , R ⁴ , and R ⁵ are methyl groups or ethyl groups. The at least one R ¹ in the formula (1) is —CH ₂ CH(OH)CH ₂ N ⁺ (R ³ )(R ⁴ )(R ⁵ )·X ⁻ , and R ³ , R ⁴ , R The hemostatic material according to claim 2, wherein ⁵ is a methyl group or an ethyl group. The hemostatic material according to claim 3 or 4, wherein at least ^one of the other R ¹ is —(CH ₂ CH ₂ O) _m H.