CN113332039B

CN113332039B - Continuous drainage sugarcane sponge dressing

Info

Publication number: CN113332039B
Application number: CN202110602713.5A
Authority: CN
Inventors: 李颖; 蓝广芊; 谢瑞琪; 胡恩岭; 陆飞; 余堃
Original assignee: Southwest University
Current assignee: Southwest University
Priority date: 2021-05-31
Filing date: 2021-05-31
Publication date: 2022-03-01
Anticipated expiration: 2041-05-31
Also published as: CN113332039A

Abstract

The invention provides a sugarcane sponge dressing with continuous drainage, aiming at the problems that the dressing has limited imbibition capacity, can not continuously absorb exudates, and the exudates are easily burnt by evaporating due to the photothermal effect in the prior art, and the like, natural sugarcane is selected as a raw material to remove lignin, hemicellulose and sugar, so that the sugarcane sponge is obtained; placing the obtained sugarcane sponge in a silver nitrate solution in a dark water bath for 15min to 1h to obtain in-situ reduced sugarcane sponge; and (3) treating the upper surface of the in-situ reduced sugarcane sponge by adopting a material with high photothermal effect or partially carbonizing to enable the upper surface of the original reduced sugarcane sponge to have good photothermal effect, and freezing and drying to obtain the sugarcane sponge dressing. The simulation plant transpiration effect, the continuous drainage wound exudate, has very high security.

Description

Continuous drainage sugarcane sponge dressing

Technical Field

The invention is applied to the technical field of dressings, and particularly relates to a sugarcane sponge dressing for continuous drainage.

Background

Wound exudate is produced in the early stages of wound healing when inflammatory mediators such as histamine and bradykinin increase capillary permeability. However, excessive exudate tends to over-hydrate the wound, inhibit fibroblast proliferation, prolong the inflammatory phase, thereby impeding the healing process and may even cause life-threatening complications leading to increased patient morbidity. In addition, poor exudate management inevitably increases management costs. Therefore, a dressing with intelligent exudate management capability is needed, which can maintain a proper moist environment of the wound surface and promote the healing of the wound surface.

In view of the limited wicking ability of dressings, various techniques have been utilized and pioneering studies have been conducted in order to effectively drain excess exudate. Hydrophobic wound dressing products are used to treat moderate to severe exudate wounds, leading to the accumulation of exudate around the skin, resulting in rewetting and excessive hydration of the wound bed, thereby increasing the risk of infection. In order to solve the rewetting problem, a continuous water-absorbing and draining wound dressing (a self-wicking for drawing out excess biological absorbent around, ADVANCED MATERIALS, 31(5) (2019)), e1804187, comprising a hydrophobic nanofiber array layer and a conventional hydrophilic medical gauze layer, was developed, which, although capable of unidirectional drainage of some excess exudate from the wound bed, did not retain its absorbent capacity when the dressing was saturated with exudate. Thus, the absorption-based removal of excess exudate from a wound is limited by the saturated absorption capacity of the material. Furthermore, since the dressing must be kept small and thin for the convenience of the patient, this inevitably limits the saturated wicking capacity of the dressing. In using these dressings, the nearly saturated dressing must be replaced with a new dressing to remove wound exudate.

In the prior art, a composite material for absorbing and evaporating exudate based on Near Infrared (NIR) response photothermal effect (biological multiplexed biological with a biological micro structure for surrounding addressing, Acta biomaterials, 100(2019) 270-279) has been developed. This material design offers the distinct advantage of constantly draining excess exudate from wet wounds, as it involves evaporation of already absorbed exudate through NIR induced photothermal effects. Unlike the absorption principle of conventional dressings, this strategy relies on osmotic delivery of fluids to remove exudates. NIR-induced exudate evaporation from the dressing matrix keeps the material in an unsaturated state and is able to drain exudate continuously from wet wounds. However, under near infrared radiation, the bulk material exhibits a relatively high temperature (>54 ℃), which may burn surrounding tissue, increasing the risk of apoptosis. While lower temperatures may be safer, moisture evaporation efficiency cannot be assured. Furthermore, these materials are man-made and therefore are often accompanied by complicated preparation procedures and contamination problems, thus greatly limiting their large scale manufacturing using bottom-up synthetic routes. In view of these shortcomings, there is an urgent need to develop a highly effective wound dressing substitute with safety utility for exudate management and promotion of wound healing prepared by a green sustainable process.

Therefore, the dressing has limited application, the volume of the dressing must be kept small and thin, so that the liquid absorption capacity of the dressing is limited, and for wounds with excessive exudate, the dressing cannot continuously absorb exudate after the dressing is saturated by liquid absorption due to limited liquid absorption capacity, the function of adjusting the moist environment of the wound surface is lost, the wound surface is easily overhydrated, and the purpose of promoting wound healing cannot be realized. Even if absorbed exudates in the dressing are evaporated through the photothermal effect, the increased temperature easily causes apoptosis and burns the skin, causing secondary damage to the wound. There is therefore a great need for a dressing which is capable of sustained absorption of wound exudate and which is safe to use.

Disclosure of Invention

Aiming at the problems that the dressing has limited imbibition capacity, can not continuously absorb exudate, can easily burn skin due to photothermal effect evaporation exudate and the like in the prior art, the invention provides the sugarcane sponge dressing which can continuously absorb wound exudate, has safety in use and can continuously drain the wound exudate through the simulated plant transpiration effect.

The technical problem to be solved by the invention is realized by adopting the following technical scheme:

a sugarcane sponge dressing with continuous drainage is characterized in that natural sugarcane is selected as a raw material to remove lignin, hemicellulose and sugar, so that sugarcane sponge is obtained; placing the obtained sugarcane sponge in a silver nitrate solution in a dark water bath for 15min to 1h to obtain in-situ reduced sugarcane sponge; and (3) treating the upper surface of the in-situ reduced sugarcane sponge by adopting a material with high photothermal effect or partially carbonizing to enable the upper surface of the in-situ reduced sugarcane sponge to have good photothermal effect, and freezing and drying to obtain the sugarcane sponge dressing.

Further, the preparation process of the sugarcane sponge comprises the following steps: selecting peeled natural sugarcane as a raw material, placing the peeled natural sugarcane in a mixed solution of sodium hydroxide and sodium sulfite for 8-14 h in a water bath, performing ultrasonic treatment for 20-60 min by using the mixed solution of sodium hydroxide, magnesium sulfate and hydrogen peroxide, and extracting by using an extractor to obtain the sugarcane sponge with lignin, hemicellulose and sugar removed.

Further, the ratio of the natural sugarcane to the mixed solution in the water bath and ultrasonic process is 1 g: 20-50 ml, and making the solution submerge the natural sugarcane.

Further, the temperature of the water bath is 60-95 ℃.

Further, the sodium hydroxide in the water bath process is 0.075-0.3 mol/L, and the sodium sulfite is 0.15-0.6 mol/L.

Further, the sodium hydroxide, the magnesium sulfate and the hydrogen peroxide in the ultrasonic process are respectively 0.01mol/L, 0.12mol/L and 2.7% in volume fraction.

Further, the extraction process of the extractor is as follows: firstly, oil bath boiling is carried out for 4-8 h at 120-180 ℃ by using an alcohol solution with the volume fraction of 60-75% in an extractor, and then boiling is carried out for 4-8 h by using deionized water.

Further, the extractor is a Soxhlet extractor.

Further, the solid-liquid mass ratio of the sugarcane sponge to the silver nitrate is 1: 10-1: 20, and the concentration of the silver nitrate is 0.1-1.0 mg/ml.

Further, the upper surface of the in-situ reduced sugarcane sponge is treated by adopting a material with high photothermal effect, namely, a nano gold rod solution or a graphene solution is sprayed on the upper surface of the in-situ reduced sugarcane sponge by a spray deposition method; the concentration of the nano gold rod solution is 0.1 mg/ml.

Further, the charcoal burning treatment of the upper surface part of the in-situ reduced sugarcane sponge means that the upper part 1/3-2/3 part of the in-situ reduced sugarcane sponge is burnt to enable the upper part to have a good photo-thermal effect.

Further, the sugarcane sponge dressing is sprayed with a gold nanorod, and then is frozen at-80 ℃ for 24 hours for drying.

According to the method, the natural sugarcane is transversely cut into blocks with the height of 0.5-3 cm before lignin, hemicellulose and sugar are removed.

In the invention, sugar in natural sugarcane is completely removed, and lignin and hemicellulose are removed by 65-90%.

The invention can also select various gramineous plant stems such as corn stalks and the like to replace natural sugarcane.

Compared with the prior art, the invention has the beneficial effects that:

(1) two important porous structures in the stems of gramineous plants such as sugarcane, corn and the like: the vascular bundle and surrounding parenchyma cells, the vascular bundle has super-hydrophilic capillary channels, which is beneficial to the transportation of water and cane sugar, the surrounding parenchyma cells are used as a closed cavity to store cane sugar, and the parenchyma cells account for about 80% of the volume of plant stems. The invention utilizes the hierarchical structure of gramineous plants such as natural sugarcane, corn and the like, utilizes a compact thin-wall cell array to perform heat insulation for near-infrared response induction, and abundant vascular bundles provide a transportation way for excessive exudate.

(2) According to the invention, gold nanorods or graphene are sprayed on the surface of the sugarcane sponge dressing, and the sugarcane has near-infrared response capability due to good biocompatibility and photothermal effect of the gold nanorods and the graphene. Based on the remarkable photothermal effect of the gold nanorods and the graphene, the near-infrared response gold nanorods and the graphene on the sugarcane substrate are used as driving forces to promote the dressing to continuously absorb the exudate from the wound, and then the moisture of the exudate is evaporated. The same effect as the gold nanorods and graphene spraying can be achieved for the partial charcoal burning of the in-situ reduced sugarcane sponges 1/3-2/3, and the good biocompatibility and photo-thermal effect are achieved.

(3) The mechanical property of the sugarcane is reduced by removing most of harder lignin and hemicellulose in the natural sugarcane, so that the sugarcane sponge dressing is soft, and the skin comfort is improved.

Drawings

Fig. 1 is an internal structure diagram and SEM images of a cross section and a longitudinal section of the continuous drainage sugarcane sponge dressing of the present invention.

FIG. 2 is a graph of the infrared thermal imaging temperature rise curve of the upper surface, the lower surface and the side surface of a continuous drainage sugarcane sponge dressing of the invention, which is compared with commercial dressings and sugarcane Sponges (SCF) without nano gold rods.

FIG. 3 is a test chart of hydrophilicity of a continuous drainage sugarcane sponge dressing and natural sugarcane.

FIG. 4 is a water absorption capacity test chart of the sugarcane sponge dressing and natural sugarcane with continuous drainage.

Fig. 5 is a graph comparing the absorption effect of a continuous drainage sugarcane sponge dressing and a commercial dressing according to the invention.

FIG. 6 is an animal experimental picture of the continuous drainage sugarcane sponge dressing, a commercial dressing and a blank group for promoting wound healing.

Detailed Description

The technical solution of the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments. It is to be understood that the following examples are only illustrative and explanatory of the present invention and should not be construed as limiting the scope of the present invention. All the technologies realized based on the above-mentioned contents of the present invention are covered in the protection scope of the present invention.

It should be noted that the terms "upper surface", "upper portion", and the like embodying an orientation in the present invention are based on an orientation or positional relationship in use or in a conventional state, and are merely for convenience of describing the present invention, and do not indicate or imply that a specific orientation is necessary. The upper surface and the upper part of the sugarcane sponge dressing are particularly the surfaces far away from the skin in use.

Example 1:

a sugarcane sponge dressing capable of conducting continuous drainage is characterized in that peeled natural sugarcane is selected as a raw material, the natural sugarcane is transversely cut into blocks with the height of 0.5-3 cm, the sugarcane blocks are placed in a mixed solution composed of 0.075mol/L sodium hydroxide and 0.15mol/L sodium sulfite, and the mixed solution containing the sugarcane blocks is placed in a water bath kettle at 85 ℃ and kept for 12 hours. Then, the sugarcane pieces were taken out and washed with deionized water, and then the sugarcane pieces were placed in a mixed solution composed of 0.01mol/L sodium hydroxide, 0.12mol/L magnesium sulfate and 2.7% by volume hydrogen peroxide for ultrasonic treatment for 45 min. Then taking out the sugarcane blocks, washing with deionized water, then placing the sugarcane blocks in a Soxhlet extractor, placing a flask of the Soxhlet extractor in an oil bath pot, placing an alcohol solution with the volume fraction of 60% in the Soxhlet extractor, setting the temperature of the oil bath pot to be 160 ℃, cooking for 6h with the alcohol solution, replacing the alcohol solution with deionized water, and cooking for 6 h. After the completion, the sugar cane pieces are taken out and washed with deionized water, at which time most of the lignin, hemicellulose and sugar in the sugar cane are removed, and the sugar cane sponge is obtained.

Placing the obtained sugarcane sponges in 0.1mg/ml silver nitrate solution according to the solid-liquid mass ratio of 1:10, and then placing the silver nitrate solution containing the sugarcane blocks in a water bath kettle at 100 ℃ in a dark place for 1 h. And then taking out the sugarcane blocks, wherein the sugarcane blocks are in a slightly black color at the moment to prove that the nano silver is successfully reduced in situ, so as to obtain the in-situ reduced sugarcane sponge.

And spraying the nanogold rod solution on the upper surface of the sugarcane sponge reduced in situ by a spray deposition method, freezing the material at-80 ℃ for 24 hours, and drying to obtain the sugarcane sponge dressing. In the sugarcane sponge, sugar is completely removed, and lignin and hemicellulose are removed by 80%.

Example 2:

a sugarcane sponge dressing capable of conducting continuous drainage is characterized in that peeled natural sugarcane is selected as a raw material, the natural sugarcane is transversely cut into blocks with the height of 0.5-3 cm, the sugarcane blocks are placed in a mixed solution composed of 0.2mol/L sodium hydroxide and 0.3mol/L sodium sulfite, and the mixed solution containing the sugarcane blocks is placed in a water bath kettle at the temperature of 95 ℃ and is kept for 8 hours. Then, the sugarcane pieces were taken out and washed with deionized water, and then the sugarcane pieces were placed in a mixed solution composed of 0.01mol/L sodium hydroxide, 0.12mol/L magnesium sulfate and 2.7% by volume of hydrogen peroxide for 25min by sonication. Then taking out the sugarcane blocks, washing with deionized water, then placing the sugarcane blocks in a Soxhlet extractor, placing a flask of the Soxhlet extractor in an oil bath pot, placing an alcohol solution with the volume fraction of 75% in the Soxhlet extractor, setting the temperature of the oil bath pot to be 130 ℃, cooking for 8h with the alcohol solution, replacing the alcohol solution with the deionized water, and cooking for 8 h. After the completion, the sugar cane pieces are taken out and washed with deionized water, at which time most of the lignin, hemicellulose and sugar in the sugar cane are removed, and the sugar cane sponge is obtained.

Placing the obtained sugarcane sponges in 0.5mg/ml silver nitrate solution according to the solid-liquid mass ratio of 1:15, and then placing the silver nitrate solution containing the sugarcane blocks in a water bath kettle at 100 ℃ in a dark place for 50 min. And then taking out the sugarcane blocks, wherein the sugarcane blocks are in a slightly black color at the moment to prove that the nano silver is successfully reduced in situ, so as to obtain the in-situ reduced sugarcane sponge.

And spraying the graphene solution on the upper surface of the sugarcane sponge reduced in situ by a spray deposition method, freezing the material at-80 ℃ for 24h, and drying to obtain the sugarcane sponge dressing. In the sugarcane sponge, sugar is completely removed, and lignin and hemicellulose are removed by 70%.

Example 3:

a sugarcane sponge dressing capable of conducting continuous drainage is characterized in that peeled natural sugarcane is selected as a raw material, the natural sugarcane is transversely cut into blocks with the height of 0.5-3 cm, the sugarcane blocks are placed in a mixed solution composed of 0.1mol/L sodium hydroxide and 0.5mol/L sodium sulfite, and the mixed solution containing the sugarcane blocks is placed in a water bath kettle at 80 ℃ and kept for 14 hours. Then, the sugarcane pieces were taken out and washed with deionized water, and then the sugarcane pieces were placed in a mixed solution composed of 0.01mol/L sodium hydroxide, 0.12mol/L magnesium sulfate and 2.7% by volume of hydrogen peroxide for 55min by sonication. Then taking out the sugarcane blocks, washing with deionized water, then placing the sugarcane blocks in a Soxhlet extractor, placing a flask of the Soxhlet extractor in an oil bath pot, placing 70% alcohol solution in the Soxhlet extractor, setting the temperature of the oil bath pot to be 180 ℃, cooking for 4h with the alcohol solution, and then replacing the alcohol solution with the deionized water and cooking for 4 h. After the completion, the sugar cane pieces are taken out and washed with deionized water, at which time most of the lignin, hemicellulose and sugar in the sugar cane are removed, and the sugar cane sponge is obtained.

Placing the obtained sugarcane sponges in a silver nitrate solution of 1.0mg/ml according to the solid-liquid mass ratio of 1:20, and then placing the silver nitrate solution containing the sugarcane blocks in a water bath kettle at 100 ℃ to keep away from light for 30 min. And then taking out the sugarcane blocks, wherein the sugarcane blocks are in a slightly black color at the moment to prove that the nano silver is successfully reduced in situ, so as to obtain the in-situ reduced sugarcane sponge.

And (3) burning 1/3-2/3 parts of the obtained in-situ reduced sugarcane sponge by charcoal, freezing the material at-80 ℃ for 24h, and drying to obtain the sugarcane sponge dressing. In the sugarcane sponge, sugar is completely removed, and lignin and hemicellulose are removed by 90%.

Experimental example 1: structural experiment of sugarcane sponge dressing

Referring to the attached figure 1, a structure diagram of the sugarcane sponge dressing obtained in the example 1 of the application after being cut open and SEM images of a cross section and a longitudinal section are shown. From the SEM images, it can be seen that the sugar cane sponge with most of the lignin, hemicellulose and sugar removed retains the structural features of natural sugar cane, the main structures are vascular bundles and parenchyma cells, the vascular bundles are mainly responsible for transporting moisture and sucrose, and the parenchyma cells are mainly responsible for storing sucrose. The vascular bundle also exhibited a hierarchical structure in which a sieve tube with a diameter of 10 μm was used for transportation of sugar and a guide tube with a diameter of 100 μm was used for transportation of water. It can also be seen from fig. 1(a) that dense elliptical pores (3-5 μm in diameter) are uniformly distributed on the inner wall of the sugar cane sponge, which allows water to spread and transfer in the transverse direction, and the pores can block air bubbles, thereby reducing air bubble-induced embolism. The vascular bundles are surrounded by lamellar parenchyma cells, the diameter of the parenchyma cells is 50-200 mu m, the length of the parenchyma cells is 200-400 mu m, and the parenchyma cells are arranged in a honeycomb shape. The vertical walls of the parenchyma cells have a small number of pores that provide a pathway for sucrose to diffuse between the vascular bundle and the parenchyma cells. These small on-wall pores limit the transport of moisture from the vascular bundle to the parenchyma cells, as compared to the dense pores in the vascular bundle. Therefore, the thin-walled cells after the desugarization treatment can be considered as closed cells filled with air. Because the thermal conductivity of static air is very low (0.026W m-1K-1), the parenchyma cells filled with the static air provide effective thermal resistance, so that the upper half part of the sugarcane sponge keeps higher temperature to be beneficial to the evaporation of exudate, and the lower half part in contact with the skin still keeps room temperature, thereby having good use safety.

Experimental example 2: photothermal effect experiment of sugarcane sponge dressing

The sugarcane sponge prepared in the embodiment 1 of the invention is directly loaded with the nanogold rods without carrying out in-situ reduction of the nanogold to obtain the sugarcane sponge dressing (Au @ SCF), the sugarcane Sponge (SCF) obtained in the embodiment 1 of the invention without loading the nanogold rods and a common commercial dressing, infrared laser with the power of 3W is used for irradiating the surface of the dressing, and the temperature rise condition of the material is observed from different angles through a TESTO865 infrared thermal imager, which is shown in an attached figure 2. As can be seen from FIG. 2A, the temperature of the sugarcane sponge dressing (Au @ SCF) material with the nanogold rod coating is obviously increased, while the temperature of the in-situ reduced sugarcane Sponge (SCF) material without the nanogold rod coating is basically kept at room temperature under the irradiation of the infrared laser. Namely, the nano gold rod endows the material with good photo-thermal effect, and the nano gold rod coating can heat the dressing under the irradiation of infrared laser. As shown in fig. 2B, under the same nanogold rod coating and the same infrared laser irradiation conditions, the lower surface of the sugarcane sponge dressing (Au @ SCF) is substantially kept at room temperature, the upper and lower surfaces of the sugarcane sponge dressing (Au @ SCF) show a large temperature difference (25 ℃), while the temperature difference of the upper and lower surfaces of the commercial dressing is not significant, and the upper and lower surfaces both have a significant temperature rise. I.e. the sugarcane sponge dressing (Au @ SCF) showed better thermal insulation compared to the commercial dressing. As can be seen from fig. 2C, the side surface of the sugarcane sponge dressing (Au @ SCF) is also basically maintained at room temperature, and the sugarcane sponge dressing (Au @ SCF) is obtained by loading the nano-gold rod on the upper surface of the dressing, so that the temperature of the sugarcane sponge dressing (Au @ SCF) is raised mainly by loading the nano-gold rod coating on the upper surface, the temperature raising region is concentrated on the nano-gold rod coating (upper surface), the temperature is not easy to pass through the material, and the sugarcane sponge has good heat insulation performance. The temperature rise of the commercial dressing is not only shown on the upper surface of the material, but also penetrates through the material to reach the lower surface of the material, although the commercial dressing has a good photothermal effect, the commercial dressing has no heat insulation performance, the skin is easily burnt while excessive moisture is evaporated, the skin is damaged, and the wound is not easy to heal. Thus, the sugarcane sponge dressing (Au @ SCF) of the invention has better photothermal effect and heat insulation performance, can promote the evaporation of redundant moisture stored in the dressing, and can protect the skin contact layer from being burnt.

Experimental example 3: water absorption performance experiment of sugarcane sponge dressing

The sugarcane sponge dressing (Au @ SCF) and the natural sugarcane (SS) are obtained by directly loading the nanogold rods without carrying out in-situ reduction on the sugarcane sponge without carrying out nano silver in the embodiment 1 of the invention, and the hydrophilicity is measured by a contact angle measuring instrument, as can be seen from the attached drawing 3, the sugarcane sponge dressing (Au @ SCF) and the natural sugarcane (SS) both show good hydrophilicity, and the sugarcane sponge dressing (Au @ SCF) has better hydrophilicity than the natural sugarcane (SS) due to the removal of lignin.

In addition, sections with the same diameter and height were placed in 15ml of blue ink for the sugarcane sponge dressing (Au @ SCF) and natural sugarcane (SS), respectively, and the absorption of the blue ink by the materials was observed. Referring to fig. 4, it can be seen that the rate of absorption of blue ink by the sugarcane sponge dressing (Au @ SCF) is faster, and that within 10s the tip of the sugarcane sponge dressing (Au @ SCF) is already full of ink, while the natural sugarcane (SS) absorbs only approximately 1/3 a. Therefore, compared with natural sugarcane (SS), the sugarcane sponge dressing (Au @ SCF) has higher water absorption speed due to the removal of lignin, and can quickly and timely absorb exudate of wounds.

Experimental example 4: experiment of management ability of sugarcane sponge dressing on exudate

The method comprises the steps of shaving the back of a New Zealand white rabbit, cutting two wounds with the same diameter of 2cm, dripping staphylococcus aureus bacteria liquid (1 multiplied by 107CFU,200 mu L) marked by a red fluorescent agent into the wounds, then respectively selecting the sugarcane sponge dressing (Ag @ Au @ SCF) and the commercially available hydrophilic dressing prepared in the embodiment 1 of the invention, covering the wounds with the sugarcane sponge dressing (Ag @ Au @ SCF) and the commercially available hydrophilic dressing for 1min, taking down the dressings, and shooting the fluorescence intensity under an ultraviolet lamp before and after the dressings are taken down.

FIG. 5 is a fluorescence photograph of the dressing after it is removed, showing that the sugarcane sponge dressing (Ag @ Au @ SCF) group has weak fluorescence intensity after the dressing covers the wound and is removed, which indicates that most of the exudate is absorbed by the dressing, and the function of the dressing for adjusting the moist microenvironment of the wound is good. The fluorescence intensity of the commercially available hydrophilic dressing is still very strong, the absorption capacity of visible exudates is small, and the wound is in a humid environment for a long time, so that the recovery of the wound is not facilitated.

Experimental example 5: wound healing promotion experiment of sugarcane sponge dressing

The method comprises the steps of shaving the backs of anesthetized New Zealand white rabbits, cutting three wounds with the same diameter of 2cm, dripping staphylococcus aureus bacterial liquid (1 multiplied by 107CFU,200 mu L) on the surfaces of the wounds, sticking commercially available woundplasts for 24 hours, respectively selecting the sugarcane sponge dressing (Ag @ Au @ SCF) and the commercially available commercial dressing prepared in the embodiment 1 of the invention, respectively covering the wounds with the sugarcane sponge dressing (Ag @ Au @ SCF) and the commercially available commercial dressing, and leaving the last wound untreated. Dorsal wounds were examined daily and photographs were taken on

days

3, 7, 11 and 15 of the healing period.

Referring to fig. 6, photographs of three wounds at

days

0, 3, 7, 11 and 15 respectively show that the wound healing degree after 15 days with the application of the sugarcane sponge dressing (Ag @ Au @ SCF) is the best, with a healing rate of 94%; commercial dressings also have a certain degree of wound healing, with a healing rate of nearly 88.1%, and untreated wounds scab with a poor healing rate of only 84.6%.

In conclusion, compared with the existing commercial dressing, the sugarcane sponge dressing has good water absorption capacity, can rapidly absorb the exudate of the wound, enables the wound to be kept relatively dry, has good photothermal effect on the surface of the dressing due to the loading of the nano gold rod, is beneficial to the evaporation of the exudate absorbed by the dressing due to the temperature rise of the surface under infrared irradiation, is not loaded with materials with good photothermal effect such as the nano gold rod and the like on the lower part of the dressing, has the heat insulation performance of natural sugarcane, keeps the contact part of the dressing and the skin at room temperature, has good heat insulation performance, ensures that the exudate rapidly absorbed by the dressing is evaporated from the upper surface of the dressing, ensures that the dressing can still keep the room temperature on the premise of keeping the good absorption performance for a long time, avoids the phenomenon of skin burn caused by the temperature rise of the dressing, the healing capacity of the wound is improved. Most lignin, hemicellulose and sugar in the natural sugarcane have been got rid of to sugarcane sponge dressing, and the getting rid of lignin, hemicellulose etc. that the texture is harder makes sugarcane sponge dressing softer, has increased the comfort level of skin, and the getting rid of lignin makes the absorbing water speed of dressing faster simultaneously, more is favorable to near wound skin to keep dry. The removal of sugar and the like avoids the defects that the dressing is easy to absorb moisture and breed bacteria and the like, and ensures that the parenchyma cells form closed cells filled with air, the static air has low heat conduction coefficient, the heat-resistant effect of the parenchyma cells is better, and the dressing has better heat-insulating property.

The above description is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above-described embodiments. It will be understood by those skilled in the art that various changes, substitutions of equivalents, and alterations can be made without departing from the spirit and scope of the invention.

Claims

1. The utility model provides a sugarcane sponge dressing of continuous drainage which characterized in that: selecting natural sugarcane as a raw material to remove lignin, hemicellulose and sugar to obtain sugarcane sponge; placing the obtained sugarcane sponge in a silver nitrate solution in a dark water bath for 15min to 1h to obtain in-situ reduced sugarcane sponge; and (3) treating the upper surface of the in-situ reduced sugarcane sponge by adopting a material with high photothermal effect or partially carbonizing to enable the upper surface of the in-situ reduced sugarcane sponge to have good photothermal effect, and freezing and drying to obtain the sugarcane sponge dressing.

2. A continuous drainage sugarcane sponge dressing as claimed in claim 1, characterized in that: the preparation process of the sugarcane sponge comprises the following steps: selecting peeled natural sugarcane as a raw material, placing the peeled natural sugarcane in a mixed solution of sodium hydroxide and sodium sulfite for 8-14 h in a water bath, performing ultrasonic treatment for 20-60 min by using the mixed solution of sodium hydroxide, magnesium sulfate and hydrogen peroxide, and extracting by using an extractor to obtain the sugarcane sponge with lignin, hemicellulose and sugar removed.

3. A continuous drainage sugarcane sponge dressing as claimed in claim 2, characterized in that: the sodium hydroxide in the water bath process is 0.075-0.3 mol/L, and the sodium sulfite is 0.15-0.6 mol/L.

4. A continuous drainage sugarcane sponge dressing as claimed in claim 2, characterized in that: in the ultrasonic process, the sodium hydroxide is 0.01mol/L, the magnesium sulfate is 0.12mol/L, and the volume fraction of the hydrogen peroxide is 2.7%.

5. A continuous drainage sugarcane sponge dressing as claimed in claim 2, characterized in that: the extraction process of the extractor is as follows: firstly, oil bath boiling is carried out for 4-8 h at 120-180 ℃ by using an alcohol solution with the volume fraction of 60-75% in an extractor, and then boiling is carried out for 4-8 h by using deionized water.

6. A continuous drainage sugarcane sponge dressing as claimed in claim 1, characterized in that: the solid-liquid mass ratio of the sugarcane sponge to the silver nitrate is 1: 10-1: 20, and the concentration of the silver nitrate is 0.1-1.0 mg/ml.

7. A continuous drainage sugarcane sponge dressing as claimed in claim 1, characterized in that: the upper surface of the in-situ reduced sugarcane sponge is treated by adopting a material with high photothermal effect, namely, a nano gold rod solution or a graphene solution is sprayed on the upper surface of the in-situ reduced sugarcane sponge by a spray deposition method; the concentration of the nano gold rod solution is 0.1 mg/ml.

8. A continuous drainage sugarcane sponge dressing as claimed in claim 7, wherein: after the sugarcane sponge dressing is sprayed with the gold nanorods, the sugarcane sponge dressing is frozen at minus 80 ℃ for 24 hours and dried.