CN103990174B - Powerful liquid absorption and drainage dressing, preparation method thereof and liquid absorption and drainage device - Google Patents

Abstract

The invention discloses a powerful liquid absorption and drainage dressing, a preparation method thereof and a liquid absorption and drainage device. The strong liquid absorption and drainage dressing comprises a vertical absorption layer, an intermediate layer and an absorption diffusion layer that are laminated in sequence. The vertical absorption layer consists of Hydrophobic fibers and hydrophilic fibers are made of raw materials, wherein the content of hydrophobic fibers is more than 30% based on the total weight of the vertical absorption layer; the middle layer is made of hydrophilic fibers or absorbent paper; the absorption diffusion The layer is made of hydrophilic fibers and less than 50% hydrophobic fibers based on the total weight of the absorbent distribution layer. The powerful fluid-absorbing and drainage dressing of the present invention can conduct moisture vertically, has high hygroscopicity, and can transmit the exudate containing inflammatory media, including slough, bacteria, matrix metalloproteinases, and biofilms adsorbed in the deep tissue, to promote wound healing.

Description

A strong liquid absorption and drainage dressing, its preparation method and liquid absorption and drainage device

technical field

The invention relates to the technical field of medical materials, in particular to a strong liquid absorption and drainage dressing, a preparation method thereof, and a liquid absorption and drainage device.

Background technique

There are a large amount of exudate, inflammatory mediators, carrion, matrix metalloproteinases and biofilms in traumatized organ tissues from superficial to deep tissues. These substances are intertwined with normal cells, which is the root cause of bacterial growth and difficult wound healing. The current dressing only aims to absorb and lock exudate through the water absorption and swelling of hydrophilic materials, and cannot achieve the purpose of "synchronous adsorption and removal of carrion, deep bacteria, matrix metalloproteinases, biofilm and exudate containing inflammatory mediators" .

At present, the hygroscopicity of the main fibrous wound dressings is generally between 12-20 grams per 100 square centimeters. The grammage of these dressings is generally between 100-150 g/m2, so their hygroscopicity is limited, up to 25 g/100 cm2. Therefore, in the case of more wound secretions, this type of dressing is difficult to cope with, and it is necessary to increase the frequency of dressing changes to meet the requirements of wound care. Clinically, dressings with higher hygroscopicity (eg, greater than 30 g/100 cm2) are desired. More importantly, as long as one area of the current wound dressing absorbs liquid, the liquid will quickly spread to other areas, such as from the wound to the healthy skin around the wound. Healthy skin can be damaged by prolonged maceration with wound exudates.

Current wound dressings are difficult to transfer liquid beyond the dressing, and the dressing can only be replaced when the liquid is saturated. If there is a lot of wound exudate, the dressing needs to be changed frequently, which not only increases the use cost of the patient, but also causes discomfort to the patient and affects wound healing. At the same time, due to the emphasis on absorption and expansion of the existing dressing, the absorbed exudate is locked and accumulated in the dressing and cannot be transferred, which limits its liquid absorption. At the same time, it is impossible to provide occasions for autolysis, enzymatic decomposition, and phagocytic decomposition of large particles of carrion adsorbed into the dressing.

Contents of the invention

In order to overcome the deficiencies in the prior art, the object of the present invention is to provide a strong liquid-absorbing and drainage dressing, which can conduct moisture vertically, has high hygroscopicity, can decompose the large particles of carrion adsorbed therein into small particles, and can absorb liquid Including the adsorbed tissue deep matrix metalloproteinase, biofilm, bacteria, etc. are delivered to promote wound healing.

Another object of the present invention is to provide a preparation method of a strong liquid absorption and drainage dressing, so as to obtain a strong liquid absorption and drainage dressing with high hygroscopicity.

In order to solve the above problems, the technical scheme adopted in the present invention is as follows:

A strong fluid-absorbing and drainage dressing, which includes a vertical absorbing layer, an intermediate layer and an absorbing diffusion layer laminated in sequence, the vertical absorbing layer is made of hydrophobic fibers and hydrophilic fibers, wherein the vertical absorbing layer Based on the total weight, the content of hydrophobic fibers is more than 30%; the middle layer is made of hydrophilic fibers or absorbent paper; the absorption and diffusion layer is made of hydrophilic fibers and less than 50% of hydrophobic Made of fiber.

The wound contact layer of ordinary hygroscopic dressings is difficult to avoid the problem of liquid lateral conduction. In the present invention, the inventors have found through research that a certain proportion of hydrophobic fibers can slow down or even prevent the lateral diffusion of liquid. Therefore, the vertical absorbent layer is composed of hydrophobic fibers and hydrophilic fibers, which can effectively conduct the wound exudate to the middle layer quickly, and this conduction is almost vertical, that is, there is little or no transverse conduction, so that most The wound secretion is quickly conducted to the middle layer, rather than diffused to the periphery; wherein the content of the hydrophobic fiber is more than 30%, preferably more than 60%, based on the total weight of the vertical absorbent layer. The middle layer adopts hydrophilic fiber or absorbent paper, which can quickly expand the liquid laterally and transfer it to the absorption diffusion layer, so that the super strong liquid absorption and liquid retention ability of the absorption diffusion layer can be fully exerted. The main functions of the absorption and diffusion layer are moisture absorption and moisturizing; the inventor also found that if the absorption and diffusion layer only uses hydrophilic fibers, the moisturizing effect is not ideal, and the use of hydrophobic fibers or the high content of hydrophobic fibers is not conducive to absorption The moisture absorption of the diffusion layer, so the absorption diffusion layer of the present invention adopts hydrophilic fibers and adds a certain amount of hydrophobic fibers to make moisture absorption and moisture retention all reach good results; wherein based on the total weight of the absorption diffusion layer, the amount of hydrophobic fibers The content is 50% or less, preferably 20% or less.

As a preferred solution of the present invention, the grammage of the vertical absorption layer is between 50-350 grams/square meter, the grammage of the middle layer is between 50-150 grams/square meter, and the grammage of the absorption diffusion layer is The gram weight is between 80-400 grams per square meter.

In the present invention, as a preferred solution, in the vertical absorbent layer, the hydrophobic fibers are polyester fibers, polypropylene fibers, nylon fibers, polyethylene fibers, hydrophobic chitosan fibers, polypropylene/hexylene bicomponent fibers, nylon /Ethylene bicomponent fiber, polyester/nylon bicomponent fiber or one or more of them are mixed in any ratio, and the hydrophilic fiber is bamboo charcoal fiber, bamboo fiber, bamboo pulp fiber, activated carbon fiber, viscose fiber, Cotton fiber, hemp fiber, fluff pulp, bacterial cellulose, absorbent acrylic fiber, absorbent polypropylene fiber, lyocell fiber, calcium alginate fiber, absorbent chitosan fiber, carboxymethyl cellulose fiber, carboxyethyl cellulose fiber , acylated chitosan fiber, carboxymethyl chitosan fiber and derivatives thereof (such as treated hydrophilic fibers such as aloe extract, cactus extract, etc.) or two or more are mixed in any ratio.

In the present invention, as a preferred solution, in the middle layer, the hydrophilic fiber is bamboo charcoal fiber, bamboo fiber, bamboo pulp fiber, activated carbon fiber, viscose fiber, cotton fiber, hemp fiber, fluff pulp, lyocell fiber One or more of wood pulp fibers and straw pulp fibers are mixed in any ratio.

In the present invention, as a preferred solution, in the absorption and diffusion layer, the hydrophilic fiber is bamboo charcoal fiber, bamboo fiber, bamboo pulp fiber, activated carbon fiber, viscose fiber, cotton fiber, hemp fiber, fluff pulp, lyocell fiber, superabsorbent cross-linked acrylic fiber, wood pulp fiber, straw pulp fiber or a mixture of two or more, the hydrophobic fiber is polyester fiber, polypropylene fiber, nylon fiber, polyethylene fiber, polypropylene/ethylene two-component fiber, nylon/ethylene bicomponent fiber, polyester/nylon bicomponent fiber or a mixture of two or more.

The vertical absorbing layer of the powerful liquid-absorbing and drainage dressing of the present invention can generally be directly applied to the wound surface. However, for burns, low-osmosis and dry wounds, before using this powerful fluid-absorbing drainage dressing, a layer of anti-adhesion dressing should be applied on the wound, such as: medical sterilized vaseline gauze, which is used to prevent adhesion to the wound and has lubricating properties. , non-stick wound, promote granulation growth, and promote wound healing.

In the present invention, the preparation of a strong fluid-absorbing and drainage dressing can be realized in the following three ways.

The specific steps of the first method are as follows:

1) Make the vertical absorption layer, the middle layer and the absorption diffusion layer respectively;

2) Composite the vertical absorbing layer, intermediate layer and absorbing diffusion layer prepared in step 1) in the order of vertical absorbing layer, intermediate layer and absorbing diffusing layer;

3) The product prepared in step 2) is cut, sterilized and packaged.

The specific steps of the second method are as follows:

1) Make the vertical absorbing layer and the middle layer respectively;

2) Composite the vertical absorbing layer and the intermediate layer prepared in step 1) to obtain a composite layer;

3) directly preparing the absorption diffusion layer on the composite layer in step 2);

4) The product prepared in step 3) is cut, sterilized and packaged.

The specific steps of the third method are as follows:

1) Make the middle layer and the absorption diffusion layer respectively;

2) Composite the intermediate layer and the absorption diffusion layer prepared in step 1) to obtain a composite layer;

3) directly preparing a vertical absorbing layer on the composite layer in step 2);

4) The product prepared in step 3) is cut, sterilized and packaged.

In the present invention, as a preferred solution, during the needling process, the needling density does not exceed 400/square centimeter.

A liquid absorption and drainage device comprises the strong liquid absorption and drainage dressing of the present invention and a fixing device for fixing the strong liquid absorption and drainage dressing on the wound. Wherein the structure of the fixing device is any structure capable of fixing the dressing of the present invention on the wound, such as through bandages, buckles, or stickers.

Compared with the prior art, the beneficial effects of the present invention are:

1. The powerful liquid absorption and drainage dressing of the present invention can be used in multiple stacks, or put together to overlap each other, so that there can be only one or more in direct contact with the wound to be treated; when multiple strong When the suction and drainage dressings are used at the same time, only one of them is in direct contact with the wound, and the secretions and bacteria will move from the strong suction drainage dressing in direct contact with the wound to the other strong suction drainage dressing or its adjacent strong suction drainage dressing by means of capillary action. Drainage dressings in which one superabsorbent drainage dressing is either in direct contact with another superabsorbent drainage dressing in direct contact with the aforementioned wound, or with one or more superabsorbent drainage dressings in between. Contact with the drainage dressing to realize the drainage and transfer of the secretion of the wound surface;

2. The powerful fluid-absorbing and drainage dressing of the present invention can be cut into any shape to fit wounds of different shapes and sizes; it can also be connected with an external exudate drainage bag to drain the deep exudate of the sinus fistula according to clinical needs;

3. The powerful fluid-absorbing and drainage dressing of the present invention can be used to coat many types of wounds, which include but are not limited to burns, infected wounds, traumas, diabetic foot injuries, tumor wounds, fungal wounds, and HIV-related wounds of humans and animals. injury, tenderness, leg ulcer, leprosy injury, amputation wound, chronic wound, radiation injury, firearm injury, metal instrument cut wound and superficial wound; Can be combined with other components to be inserted into deep wounds or incisions for suction and drainage;

4. The powerful liquid-absorbing and drainage dressing of the present invention can not only absorb wound secretions, but also keep secretions, bacteria, carrion, biofilm, matrix metalloproteinase, etc. away from the wound because of the capillary effect in the structure of the strong liquid-absorbing and drainage dressing; The strong suction and drainage dressing can remove necrotic tissue, remove nutrients from biofilm, and reduce harmful cytokines on the wound surface;

5. The strong liquid-absorbing drainage dressing of the present invention can be used to release the stench of the wound; due to the strong adsorption capacity of the strong liquid-absorbing drainage dressing, it can absorb the odor released by the wound and reduce the emission of odor into the air;

6. The powerful liquid-absorbing and drainage dressing of the present invention has a capillary effect, utilizes the negative pressure suction produced by the water potential energy pressure difference at the two ends of the capillary in the fiber to make the secretions discharged through the drainage of the dressing, and realize the transfer adsorption of the secretions, thus being Absorbed liquid can be transferred to a relatively dry material site; in addition, because the outer surface of the vertical absorbent layer is relatively non-adhesive, the superabsorbent drainage dressing can comfortably face the wound when treating the wound;

7. The strong fluid-absorbing and drainage dressing of the present invention can effectively promote the generation of new granulation on the wound surface, reduce edema and eschar, thereby accelerating the healing of the wound surface;

8. The powerful fluid-absorbing and drainage dressing of the present invention can also be used for wiping blood, absorbing exudate, and absorbing body fluids during operations.

The present invention will be described in further detail below in conjunction with the accompanying drawings and specific embodiments.

Description of drawings

Fig. 1 is the structural representation of strong fluid absorption and drainage dressing of the present invention;

Fig. 2 is the change figure of each group's gap area (n=6) in the progressive necrosis inhibition experiment of rat deep second-degree burn wound model;

Fig. 3 is each group's scald wound depth (n=6) change figure in rat deep second degree burn wound model progressive necrosis inhibition experiment;

Fig. 4 is the photomicrograph of group A after silver staining in the deep second degree scald wound of rats inoculated with SA model biofilm inhibition experiment;

Fig. 5 is the photomicrograph of group B after silver staining in the deep second degree scald wound of rats inoculated with SA model biofilm inhibition experiment;

Fig. 6 is the photomicrograph of group C after silver staining in the deep second degree scald wound of rats inoculated with SA model biofilm inhibition experiment;

Figure 7 is the MMP1 determination situation of groups A, B, and C at each time period in the metalloproteinase inhibition experiment of diabetic chronic refractory wound rat model;

Figure 8 shows the measurement of MMP2 in groups A, B, and C at each time period in the metalloproteinase inhibition experiment of rat models of diabetic chronic refractory wounds.

Detailed ways

Example 1

As shown in Figure 1, a strong fluid-absorbing drainage dressing includes:

Vertical absorbent layer 3: containing 65% by weight of polyester fibers with a fiber size of 2.0-2.5 denier and a length of 45-55 mm; 35% by weight of bamboo charcoal fibers with a fiber size of 2.0-2.5 denier and a length of It is 45-55 mm; the two fibers are weighed in proportion and then evenly mixed, then opened, carded, laid and needle-punched into cloth, the needle-punched density is 350/square centimeter; the grammage of the fabric is 250 g/m2;

Middle layer 2: Contains 100% by weight cotton fibers with a fiber size of 1.5-2.5 denier and a length of 25-35 mm; weighed and mixed, then opened, carded, laid and needled into cloth; The grammage of the finished fabric is 80 grams per square meter;

Absorbent diffusion layer 1: Contains 35% by weight of superabsorbent cross-linked acrylic fibers with a denier of 2.0-2.7 and a length of 10-15 mm; 45% by weight of wood pulp fibers with a denier of 2.0-2.5 Denier, 10-15mm in length; Contains 20% by weight of polyester fiber, its fiber denier is 2.0-2.5 denier, and its length is 45-55mm; the three fibers are weighed in proportion and mixed evenly , and then loosened, carded, laid and needle-punched into cloth with a needle-punched density of 350 g/cm2; the grammage of the finished fabric was 320 g/m2; and then the three layers were compounded together by needle-punching ;

The prepared fabric was cut into 10×10 cm, then packaged and sterilized by cobalt 60, and the gram weight of the strong fluid absorption and drainage dressing was 650 g/m2.

Example 2

A super absorbent drainage dressing comprising:

Vertical absorbent layer: 60% by weight of hydrophobic chitosan fibers with a denier of 2.2 and a length of 51 mm; 40% by weight of viscose fibers with a denier of 2.0-2.5 and a length of 45-55 mm; the two fibers are weighed in proportion and then evenly mixed, then opened, carded, laid and needle-punched into cloth. The needle-punched density is 400/square centimeter; the grammage of the finished fabric is 200 grams per square meter;

Middle layer: 30% by weight of viscose fibers with a fiber size of 2.0-2.5 denier and a length of 45-55 mm; 70% by weight of cotton fibers with a fiber size of 1.5-2.5 denier and a length of 25-35mm; the two fibers are weighed in proportion and then evenly mixed, then loosened, carded, laid and needle-punched into cloth; the grammage of the finished fabric is 80 grams per square meter;

Absorption and diffusion layer: Bamboo charcoal fiber containing 35% by weight, whose fiber size is 2.0-2.5 denier, and a length of 45-55 mm; 40% by weight of viscose fiber, whose fiber size is 2.0-2.5 denier, length 45-55 mm; 25% weight polypropylene fiber, the fiber fineness is 2.0-2.5 denier, and the length is 38 mm; the three fibers are weighed in proportion and then mixed evenly, then loosened, carded, laid Netting and needling into cloth, the needling density is 350/square centimeter; the grammage of the finished fabric is 320 grams/square meter;

Lay the vertical absorbing layer, middle layer and absorbing and diffusing layer fabrics on the bottom curtain of the net-laying machine as required, and feed them into the needling machine with a needling frequency of 200/square centimeter to realize the compounding of three-layer fabrics;

The prepared fabric was cut into 10×10 cm, then packaged and sterilized by ethylene oxide, and the grammage of the strong fluid absorption and drainage dressing was 600 g/m2.

Example 3

A super absorbent drainage dressing comprising:

Vertical absorbent layer: 60% by weight polyester fibers with a denier of 2.0-2.5 and a length of 45-55 mm; 40% by weight of cotton fibers with a denier of 1.5-2.5 and a length of 25-35 mm; the two fibers are weighed in proportion and then evenly mixed, then loosened, carded, laid and needled into cloth. The needle density is 350/square centimeter; the grammage of the finished fabric is 250 grams per square meter;

Middle layer: containing 30% by weight of viscose fiber, its fiber fineness is 2.0-2.5 denier, and its length is 45-55 mm; 70% by weight of bamboo fiber, its fiber fineness is 5-6 denier, its length is 80-90 mm; the two fibers are weighed in proportion and then evenly mixed, then loosened, carded, laid and needle-punched into cloth, and the weight of the fabric is 80 grams per square meter;

Absorption and diffusion layer: Bamboo charcoal fiber containing 35% by weight, whose fiber size is 2.0-2.5 denier, and a length of 45-55 mm; 50% by weight of viscose fiber, whose fiber size is 2.0-2.5 denier, and its length 45-55 mm, containing 15% by weight of polyester fiber, the fiber fineness is 2.0-2.5 denier, and the length is 45-55 mm; the three fibers are weighed in proportion and then uniformly mixed, and then loosened. Carding, laying and needling into cloth, the needling density is 350/square centimeter. The grammage of the fabric is 320 grams per square meter;

The vertical absorbing layer, the middle layer and the absorbing and diffusing layer fabrics are stacked together as required, and placed in an oven for hot-melt lamination;

The prepared fabric was cut into 10×10 cm, then packaged and sterilized by ethylene oxide, and the grammage of the strong fluid absorption and drainage dressing was 650 g/m2.

Example 4

A super absorbent drainage dressing comprising:

Vertical absorbent layer: 70% by weight polypropylene fibers with a denier of 2.0-2.5 and a length of 38 mm; 30% by weight of lyocell fibers with a denier of 1.7 and a length of 51 mm; The two fibers are weighed in proportion and mixed evenly, then loosened, carded and laid;

Middle layer: 30% by weight of viscose fibers with a fiber size of 2.0-2.5 denier and a length of 45-55 mm; 70% by weight of cotton fibers with a fiber size of 1.5-2.5 denier and a length of 25-35 mm, the two fibers are weighed in proportion and then evenly mixed, then loosened, carded, laid and needle-punched into cloth; the grammage of the finished fabric is 80 grams per square meter;

Absorbent diffusion layer: 85% by weight of viscose fibers with a fiber titer of 2.0-2.5 denier and a length of 45-55 mm, containing 15% by weight of polyester fibers with a fiber titer of 2.0-2.5 denier and a length of It is 45-55 mm, and the two fibers are weighed in proportion and mixed evenly, then opened, carded, laid and needle-punched into cloth; the needle-punched density is 350/square centimeter, and the grammage of the fabric is 320 g/m².

When preparing the vertical absorption layer, the middle layer and the absorption and diffusion layer fabric are placed on the bottom curtain of the net lapper in sequence (the absorption and diffusion layer fabric is on the bottom, and the middle layer fabric is on the top), and then the opening, carding and web laying processes are started. The fiber web of the vertical absorbent layer is laid directly on the middle layer (absorbent diffusion layer is at the bottom), and fed into the needle loom together at a frequency of 150/square centimeter, so that the fibers of the vertical absorbent layer are pierced through the middle layer and are always The stabs go outside the absorbent diffusion layer to bond the three layers of fabric together. The average gram weight of the vertical absorbent layer is 300 g/m2;

The prepared fabric was cut into 10×10 cm, then packaged and sterilized by cobalt 60, and the gram weight of the strong fluid absorption and drainage dressing was 700 g/m2.

Detection test

The effects of the powerful fluid-absorbing and drainage dressing of the present invention are tested by using a mouse burn model experiment, and the specific experiments are as follows.

1. Bacterial removal experiment of rat model wound surface after bacterial inoculation after acute injury

1.1 Experimental grouping

Thirty-six SD rats, weighing between 200 and 250 g, were divided into three groups, A, B, and C, with 12 rats in each group. See Table 1 for specific grouping information.

Table 1: Grouping of experimental animals

group deal with Number of animals (only) Number of wounds (pieces) A strong suction drainage dressing 12 12 B plain dressing 12 12 C blank group 12 12

1.2 Experimental steps

1.2.1 Model making: Rats in each group were anesthetized by intraperitoneal injection of 15% chloral hydrate at 2ml/kg. After successful anesthesia, the limbs were fixed on the rat operating table in the prone position, the back body hair was removed with an electric pet shaver, rinsed with clean water, and sterilized with 75% alcohol. For wounds with layered skin defects, rinse with hydrogen peroxide, chlorhexidine, and normal saline locally, disinfect the skin around the wounds with 75% alcohol, and dry them with sterile gauze.

1.2.2 Wound inoculation: use a 1ml syringe to prepare Escherichia coli (EC), Staphylococcus aureus (SA), and Pseudomonas aeruginosa (PSA) suspensions with a concentration of 1×10 ⁹ cfu/ml Drop 0.5ml on the wound and let it distribute naturally. Ten minutes later, fix the powerful fluid-absorbing drainage dressing and the ordinary dressing on the wounds of each group, replace them every 12 hours, and observe after 24 hours.

1.2.3 Wound Bacteria Collection: Dip a sterile cotton swab into a saline solution (in a 5ml sterile saline test tube), roll it from one side of the wound to the other, spread it evenly on the wound once, and immediately put it into a dry sterile In the test tube, put 1ml of sterile normal saline to wash and dilute it, then inoculate it on MH culture dish, and after 24 hours of constant temperature cultivation at 37°C, count the number of colony forming (cfu) on the inoculated culture dish; ), 24 hours later, measure the number of wound EC, SA, and PSA respectively; according to the formula (average bacterial count value after ten minutes - average bacterial count value after 24 hours)/average bacterial count value after ten minutes, calculate A, The removal rates of three different bacteria in groups B and C were compared; all the data were processed with SPSS16.0 statistical software, and the analysis of variance and multiple comparisons between the means of multiple samples were performed respectively, and P<0.05 indicated a significant difference.

1.3 Bacterial culture results on the wound: Bacteria were collected from the wound, and after inoculation and culture, the number of bacteria in each group was calculated; see Table 2 for the results of analysis and comparison.

Table 2: Comparison of mean removal rates of wound EC, SA, and PSA at 24 hours after injury (%)

group EC SA PSA A 78.82* 76.11* 82.36* B 3.57☆ 3.40☆ 3.77☆ C 1.96 2.01 1.49

*Note: There is a significant difference between group A and group B and C, P<0.05

☆Note: There is no significant difference between group B and group C, P>0.05

The results in Table 2 show that the strong suction and drainage dressing can effectively remove pathogenic bacteria such as EC, PSA, and SA within 24 hours.

2. Inhibition experiment of progressive necrosis in rat deep second-degree burn wound model

2.1 Experimental steps

2.1.1 Model making: The test refers to the copper comb scald model invented by Regas FC and Ehrlich HP. The special copper comb scald device weighs 150g and consists of 4 protruding combs. Each comb is 10mm wide and 20mm long. Contact the skin after heating to form a scald wound; there are 3 concave gaps between the comb teeth, each 5 mm wide and 20 mm long, and do not touch the skin when scalded, and the formed area is called the gap area; the day before the experiment, the back of the rat was pushed with electricity. Cut off the hair and wash with water to avoid skin irritation. Give the animal anesthesia by intraperitoneal injection of 1% pentobarbital sodium at 40 mg/kg according to its body weight, fix it on the animal experiment table, immerse the special copper comb scald device in pre-boiled boiling water (measured water temperature is 100°C), and heat evenly After 5 minutes, dry it; place it on the skin at 0.5cm away from both sides of the midline of the back of the rat successively, without applying any pressure, and the corresponding contact time with the skin is 20s; from this, 4 scald wounds on both sides of the back and their Three unburned interstitial areas in between. A single layer of oiled gauze was given to cover the wound without other treatment; 2 hours after the injury, part of the wound tissue specimen was cut with a scalpel; the specimen was 3×10 mm full-thickness skin tissue including the gap area and the part of the burn area on both sides, which was placed Overnight in 10% paraformaldehyde; remove the specimen and place it in a Leica automatic tissue dehydrator; embedding in paraffin the next day, after cooling and fixing, make 4 μm thick sections and dry; HE staining, dehydration with gradient alcohol, until transparent in xylene , Histological observation after sealing with neutral gum, degeneration and necrosis of the epidermis can be seen, about 2/3 of the collagen in the upper dermis is homogeneously red-stained, and the lower 1/3 can be seen that some small blood vessels are blocked by red blood cells in the lumen, and some cells in the skin appendages have The nuclei are condensed or lysed, which is consistent with the characteristics of deep second-degree burns and scalds.

2.1.2 Grouping experiment: according to the method above, 18 rats were divided into three groups A, B, and C after undergoing deep second-degree burns, with 6 rats in each group. group) and blank (group C), in which group A and group B changed the dressing every 12 hours; after 24 hours and 48 hours, some wound tissue samples were cut out according to the method described in 2.1.1, embedded in paraffin, fixed and sectioned, and stained with HE Post-observation; GraphPad Prism5.0 software was used to conduct statistical analysis on the experimental data, the area of the gap area and the depth of the wound surface were represented by x±s, and the paired t test was used for comparison between the two groups. P<0.05 means significant difference.

2.2 Experimental results

2.2.1 Changes in the wound and interstitial area: General observation of the wound, including the area of hair and interstitial area, whether there are bleeding points or ecchymosis, etc. If there is, it is considered as necrosis. A digital camera was taken vertically at a distance of 20 cm from the wound and saved. A steel ruler was placed next to the wound as a reference. Image pro5.0 image analysis software was used to detect changes in the area of the gap area. The results are shown in Figure 2.

The results in Figure 2 show that after scalding, the area of the interstitial area in groups B and C continued to decrease, the area in group A decreased slightly after 24 hours compared with that after scalding, and the area remained basically unchanged after 48 hours. Compared with groups B and C at two time points , all P<0.05. It shows that the treatment effect of group A is obvious, and the progressive necrosis of the gap area is limited.

2.2.2 Detection of wound depth: put the HE-stained section under an optical microscope to observe the burn wound, use the swelling of keratinocytes, collagen degeneration and homogeneous red staining as indicators to determine the depth of the wound, and use NIF image software to record and save the image, and then use Image Pro5.0 image analysis software was used to calculate the wound depth; 3 slices were observed at each time point in each group, and 5 positions were taken from each slice, and the average value was taken. The results are shown in Figure 3.

The results in Figure 3 show that the depth of wounds in groups B and C increased to varying degrees after scalding, while the depth of wounds in group A tended to decrease. Compared between groups at each time point, group A had the smallest depth, followed by group B, and group C had the largest depth; compared group A with groups B and C, P<0.05; compared group B with group C, P>0.05. It shows that the treatment in group A is effective and limits the deepening of the wound depth.

3. Inhibition experiment of SA model biofilm inoculation on deep partial degree scald wounds of rats

3.1 Experimental steps:

3.1.1 Model making: 3 SD rats were prepared according to the method of 2.1.1 above to prepare the model of rat deep second-degree scald wound, and then the wound surface was inoculated with SA according to the method of 1.2.1 and 1.2.2 above to make rat deep II degree scald wound model. Inoculated SA model in superficial scald wounds.

3.1.2 Experimental grouping: 3 rats were divided into A, B, C three groups, each group 1, respectively with the strong liquid suction and drainage dressing (A group) of the present invention, common dressing (B group), blank treatment ( Group C), in which dressings were changed every 12 hours in groups A and B; wound tissues of 3×10 mm in size were cut out for inoculation on 7 days, and treated by the following silver staining method for observation. The results are shown in Figure 4-6.

The treatment steps of silver staining method are as follows: ① Rinse with sterilized normal saline several times to remove planktonic bacteria; ② Fix in 25% glutaraldehyde PBS solution for 1 hour; ③ Wash with distilled water for 1 minute; ④ Combine with saturated calcium chloride solution for 15 minutes; ⑤ Wash with distilled water 1 min; ⑥ 5% silver nitrate solution for 15 min; ⑦ 1% hydroquinone solution for 2 min; ⑧ distilled water rinse for 1 min; ⑨ 5% sodium thiosulfate solution for 2 min; ⑩ distilled water rinse for 1 min.

3.2 Experimental results

Figure 4 is an optical microscope photo of group A after silver staining, and scattered black dots or black spots can be seen, without black-stained flocculent film-like objects; Figure 5 is an optical microscope photo of group B after silver staining, in which the black stained part is Cotton-like film-like objects are SA biofilms; Figure 6 is an optical microscope photo of group C after silver staining, and it can be seen that bacteria aggregate into clusters, forming large SA biofilms. The results showed that strong fluid absorption and drainage dressing can significantly inhibit the formation of bacterial biofilm.

4. Metalloproteinase inhibition experiment of rat model of diabetic chronic refractory wound

4.1 Experimental steps

4.1.1 Model making: 3 Wistar rats, weighing 200-250g, fasted for 12 hours before the experiment, and drank water quantitatively; on the day of the experiment, the body weight was weighed, blood was collected from the tail vein and urine was collected, and the basal blood sugar and blood sugar levels were measured by blood glucose meter and test strip method respectively. Urine sugar, and then intraperitoneally inject 3% alloxan at 150 mg/kg body weight; after 1 week, when the blood sugar concentration of the animal is greater than 11mmol/L and the urine sugar is ++++ (>20g/L), the diabetes model can be considered to be replicated successfully . Take 3 above-mentioned artificially replicated diabetic rats, anesthetize with 3% pentobarbital sodium (25mg/kg) intraperitoneal injection, shave the back, and routinely disinfect; A circular hole was made on both sides of the upper spine, deep to the subcutaneous, with a diameter of 1.8cm and a wound area of 2.54cm ² ; after hemostasis, a strong fluid-absorbing drainage dressing (group A), a common dressing (group B), and a blank dressing (group C) were used respectively. ) treatment, wherein group A and group B changed the dressing every 12 hours; animals in each group were fed in a single cage, and water and food were rationed. The food intake, drinking water volume, body weight and urine sugar changes of the animals were measured daily, and the blood sugar was measured once a week; the blood sugar of diabetic animals was maintained between 11 and 16.5 mmol/L by supplementary injection of alloxan or insulin (2u/only) .

4.1.2 Experimental method: 4 × 3 × 3mm granulation tissue was cut from the center of the wound on the 1st, 4th, and 7th day after the wound treatment, and immediately frozen with liquid nitrogen, and transferred to -70°C refrigerator for 2 months after 48 hours; Total RNA was extracted with Trizol kit and stored at -70°C; MMPI and MMP2 were amplified using RT-PCR kit from Promega, and finally the density of each product was measured with a Band-scan scanning system. All products were sequenced. It was confirmed that they were MMP1 and MMP2 respectively; the density value of each index at each time point was represented by X±S, analyzed by unpaired t test, and P<0.05 indicated a significant difference. The results are shown in Figures 7 and 8.

4.2 Experimental results

Figure 7 and Figure 8 show the measurement of MMP1 and MMP2 in groups A, B, and C at different time periods. The results show that strong fluid-absorbing and drainage dressings can significantly reduce MMP1 and MMP2 in diabetic chronic wounds. Compared with P<0.05, there was a significant difference.

To sum up, the powerful fluid-absorbing and drainage dressing of the present invention can remove most of the germs, carrion, biofilm and matrix metalloproteinases on the wound surface.

The above-mentioned embodiment is only a preferred embodiment of the present invention, and cannot be used to limit the protection scope of the present invention. Any insubstantial changes and substitutions made by those skilled in the art on the basis of the present invention belong to the scope of the present invention. Scope of protection claimed.

Claims (5)

1. a strong liquid-absorbing and drainage dressing is characterized in that it comprises a vertical absorbing layer, an intermediate layer and an absorbing diffusion layer fitted successively, and the vertical absorbing layer is made of hydrophobic fibers and hydrophilic fibers, wherein Based on the total weight of the vertical absorption layer, the content of hydrophobic fibers is more than 30%; the middle layer is made of hydrophilic fibers or absorbent paper; the absorption diffusion layer is made of hydrophilic fibers and absorbs the total weight of the diffusion layer The weight of the vertical absorbent layer is between 50-350 grams/square meter, the weight of the middle layer is between 50-150 grams/square meter, and the absorbent The gram weight of the diffusion layer is between 80-400 grams per square meter; In the vertical absorption layer, the hydrophobic fiber is polyester fiber, polypropylene fiber, nylon fiber, polyethylene fiber, hydrophobic chitosan fiber, polypropylene/hexylene bicomponent fiber, nylon/ethylene bicomponent fiber, polyester/ One or more than two kinds of nylon bicomponent fibers are mixed in any ratio, and the hydrophilic fibers are bamboo charcoal fiber, bamboo fiber, bamboo pulp fiber, activated carbon fiber, viscose fiber, cotton fiber, hemp fiber, fluff pulp, bacteria Cellulose, water-absorbing acrylic fiber, water-absorbing polypropylene fiber, lyocell fiber, calcium alginate fiber, water-absorbing chitosan fiber, carboxymethyl cellulose fiber, carboxyethyl cellulose fiber, acylated chitosan fiber, carboxymethyl One or more of chitosan fibers and derivatives thereof are mixed in any ratio; In the middle layer, the hydrophilic fiber is bamboo charcoal fiber, bamboo fiber, bamboo pulp fiber, activated carbon fiber, viscose fiber, cotton fiber, hemp fiber, fluff pulp, lyocell fiber, wood pulp fiber, straw pulp fiber Mix one or more than two kinds in any ratio; In the absorption diffusion layer, the hydrophilic fiber is bamboo charcoal fiber, bamboo fiber, bamboo pulp fiber, activated carbon fiber, viscose fiber, cotton fiber, hemp fiber, fluff pulp, lyocell fiber, superabsorbent cross-linked acrylic fiber, wood One or more kinds of pulp fiber and straw pulp fiber are mixed, and the hydrophobic fiber is polyester fiber, polypropylene fiber, nylon fiber, polyethylene fiber, polypropylene/ethylene bicomponent fiber, nylon/ethylene bicomponent fiber , Polyester/Nylon bicomponent fibers or a mixture of two or more. 2. The powerful liquid-absorbing and drainage dressing as claimed in claim 1, is characterized in that, it is prepared by the following steps: 1) Make the vertical absorption layer, the middle layer and the absorption diffusion layer respectively; 2) Composite the vertical absorbing layer, intermediate layer and absorbing diffusion layer prepared in step 1) in the order of vertical absorbing layer, intermediate layer and absorbing diffusing layer; 3) The product prepared in step 2) is cut, sterilized and packaged. 3. The powerful fluid-absorbing and drainage dressing according to claim 1, characterized in that, it is prepared through the following steps: 1) Make the vertical absorbing layer and the middle layer respectively; 2) Composite the vertical absorbing layer and the intermediate layer prepared in step 1) to obtain a composite layer; 3) directly preparing the absorption diffusion layer on the composite layer in step 2); 4) The product prepared in step 3) is cut, sterilized and packaged. 4. The powerful fluid-absorbing and drainage dressing according to claim 1, characterized in that it is prepared through the following steps: 1) Make the middle layer and the absorption diffusion layer respectively; 2) Composite the intermediate layer and the absorption diffusion layer prepared in step 1) to obtain a composite layer; 3) directly preparing a vertical absorbing layer on the composite layer in step 2); 4) The product prepared in step 3) is cut, sterilized and packaged. 5. A liquid absorption and drainage device, characterized in that it comprises the powerful liquid absorption and drainage dressing according to claim 1 and a fixing device for fixing the strong liquid absorption and drainage dressing on the wound.