CN118059288A - Janus fiber dressing with unidirectional drainage, photo-thermal evaporation and sterilization functions and preparation method and application thereof - Google Patents

Abstract

The invention relates to a Janus fiber dressing with unidirectional drainage, photo-thermal evaporation and sterilization functions, and a preparation method and application thereof. And dissolving the photothermal reagent and the hydrophilic fiber in a solvent to obtain a spinning solution, depositing the spinning solution on a hydrophobic material by an electrostatic spinning method to obtain a Janus fiber dressing, and drying in vacuum at 90 ℃. The Janus fiber dressing includes a hydrophobic fiber substrate layer and a hydrophilic fiber layer with a photo-thermal agent. Compared with the prior art, the Janus fiber dressing prepared by the invention can drain wound exudate unidirectionally, can generate local high temperature under illumination, has the temperature of more than 55 ℃, and can destroy bacterial morphology and kill bacteria. In addition, evaporation of wound exudate can be enhanced by photothermal effect, so that the dressing is in an unsaturated state, and continuous discharge of seepage is ensured.

Description

A Janus fiber dressing with one-way drainage, photothermal evaporation and sterilization functions and its preparation method and application

Technical Field

The invention relates to the technical field of biomaterials and regenerative medicine, and in particular to a Janus fiber dressing with unidirectional drainage, photothermal evaporation and sterilization functions, and a preparation method and application thereof.

Background technique

Diabetic wound ulcers are common complications of diabetes. These chronic wounds that are difficult to heal may cause prolonged pain, decreased quality of life, and even amputation in severe cases. Generally speaking, excessive tissue exudate and persistent inflammatory response are important reasons that hinder the healing of diabetic wounds. Diabetic wound exudate has a high blood sugar level. This high blood sugar environment creates a favorable microenvironment for bacterial proliferation and aggravates the inflammatory response. Therefore, effective exudate management and reduction of bacterial infection are essential for promoting diabetic wound healing.

In recent years, many hydrophilic dressings with good water absorption and retention capabilities have been developed for wound exudate management, such as gauze, sponges, hydrogels, etc. However, hydrophilic dressings saturated with high-sugar exudate tend to adhere to the wound surface, causing bacterial growth around the wound. When the dressing is changed again, secondary trauma often occurs, greatly increasing the patient's pain.

Therefore, it is necessary to develop a dressing with self-evaporating unidirectional drainage and simultaneously having photothermal evaporation and sterilization capabilities.

Summary of the invention

The purpose of the present invention is to provide a Janus fiber dressing with unidirectional drainage, photothermal evaporation and sterilization functions and its preparation method and application in order to overcome the defects of the above-mentioned prior art. The dressing contains a hydrophobic membrane and a hydrophilic membrane, which can achieve unidirectional drainage of wound exudate and can use photothermal therapy to treat diabetic wounds infected with bacteria.

The purpose of the present invention can be achieved by the following technical solutions:

The present invention provides a method for preparing a Janus fiber dressing with unidirectional drainage, photothermal evaporation and sterilization functions, wherein an ammonia solution is dissolved in an alcohol/water mixture to obtain a mixed solution, a photothermal agent is dissolved in the mixed solution, and nanoparticles of the photothermal agent are obtained after drying;

The nanoparticles and hydrophilic fibers are then dissolved in a solvent to obtain a spinning solution. The hydrophobic fibers are used as a substrate, and the spinning solution is deposited on the hydrophobic fibers by an electrospinning method. After drying, a Janus fiber dressing with unidirectional drainage, photothermal evaporation and sterilization functions is obtained.

Furthermore, the ratio of the added amounts of the photothermal reagent, the hydrophilic fiber and the solvent is (0.02-0.10) mg: (0.1-1.0) g: (3-10) mL; preferably, the ratio of the added amounts of the photothermal reagent, the hydrophilic fiber and the solvent is 0.084 mg: 0.28 g: 3 mL.

Furthermore, in the electrospinning method, the electrospinning voltage is 3-10 kV, the speed is 0.01-0.10 mm·min ^-1 , and the receiving distance is 5-25 cm; preferably, the electrospinning voltage is 8 kV, the speed is 0.04 mm min ^-1 , and the receiving distance is 10 cm.

Further, the photothermal reagent includes one of polydopamine (PDA), copper sulfide or indocyanine green; preferably, the photothermal reagent is polydopamine (PDA);

The hydrophilic fiber includes one of polyacrylonitrile (PAN), chitosan, polyvinyl pyrrolidone (PVP), polyvinyl alcohol (PVA) or acetate fiber; preferably, the hydrophilic fiber is polyacrylonitrile (PAN).

Further, the solvent includes one of N-N dimethylformamide (DMF), ethanol, water, dimethyl sulfoxide (DMSO) or tetrahydrofuran (THF); preferably, the solvent is N-N dimethylformamide (DMF);

The hydrophobic fiber includes one of polypropylene (PP), polylactic acid (PLA), polycaprolactone (PCL) or polyurethane (PU); preferably, the hydrophobic fiber is polypropylene (PP).

The present invention also provides a Janus fiber dressing with unidirectional drainage, photothermal evaporation and sterilization functions. The Janus fiber dressing comprises a hydrophobic fiber base layer and a hydrophilic fiber layer with a photothermal agent.

Furthermore, the dressing can achieve a unidirectional drainage function of discharging water from the hydrophobic layer to the hydrophilic layer.

Furthermore, the dressing can generate local high temperature under light, and the local high temperature is greater than 55°C.

Furthermore, the local high temperature can destroy the morphology of bacteria and kill the bacteria, and accelerate the rate of one-way drainage by promoting the evaporation rate.

The present invention also provides an application of a Janus fiber dressing having unidirectional drainage, photothermal evaporation and sterilization functions, wherein the Janus fiber dressing is used for preparing a medicine for promoting wound healing in diabetic patients.

Compared with the prior art, the present invention has the following advantages and beneficial effects:

1. The Janus fiber dressing prepared by the present invention includes hydrophobic and hydrophilic membranes, and can drain wound exudate in one direction.

2. The Janus fiber dressing prepared by the present invention can generate local high temperature under light, the temperature is greater than 55°C, which can destroy the bacterial morphology and kill bacteria. In addition, the evaporation of wound exudate can be enhanced through the photothermal effect, so that the dressing is in an unsaturated state, ensuring the continuous discharge of exudate.

3. The present invention is used to treat bacterially infected diabetic wounds through photothermal therapy. Under 808nm laser irradiation, the polydopamine Janus fiber dressing loaded with photothermal agent can effectively kill bacteria on the wound.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a schematic diagram of Janus fiber dressing's one-way drainage, photothermal evaporation, sterilization, and application in promoting diabetic wound healing

FIG2 is a scanning electron microscope image of a Janus fiber dressing having unidirectional drainage, photothermal evaporation and sterilization functions in Example 1;

FIG3 is a schematic diagram of the unidirectional transport function of the Janus fiber dressing in Experimental Example 1;

FIG4 is a diagram showing the photothermal heating effect of the Janus fiber dressing under 808 nm laser irradiation in Experimental Example 2;

FIG5 is a diagram showing the evaporation effect of the Janus fiber dressing in Experimental Example 3;

FIG6 is a diagram showing the antibacterial effect of the Janus fiber dressing in Experimental Example 4;

FIG. 7 is a diagram showing the therapeutic effect of Application Example 1 on diabetic wounds in mice.

Detailed ways

The specific implementation methods of the present invention are described in detail below through examples. These examples are implemented on the premise of the scheme described in the present invention, and provide detailed implementation methods and specific operating processes, but the protection scope of the present invention is not limited to the following examples.

The present invention is further described below in conjunction with the accompanying drawings and specific embodiments. Any features such as component models, material names, connection structures, preparation methods, materials, structures or composition ratios not clearly described in this technical solution are deemed to be common technical features disclosed in the prior art.

The present invention provides a method for preparing a Janus fiber dressing with unidirectional drainage, photothermal evaporation and sterilization functions, wherein an ammonia solution is dissolved in an alcohol/water mixture to obtain a mixed solution, a photothermal agent is dissolved in the mixed solution, and nanoparticles of the photothermal agent are obtained after drying;

The nanoparticles and hydrophilic fibers are then dissolved in a solvent to obtain a spinning solution. The hydrophobic fibers are used as a substrate, and the spinning solution is deposited on the hydrophobic fibers by an electrospinning method. After drying, a Janus fiber dressing with unidirectional drainage, photothermal evaporation and sterilization functions is obtained.

The ratio of the amount of the photothermal agent, the hydrophilic fiber and the solvent added is (0.02-0.10) mg: (0.1-1.0) g: (3-10) mL. In the electrospinning method, the voltage of the electrospinning is 3-10 kV, the speed is 0.01-0.10 mm min-1, and the receiving distance is 5-25 cm.

The photothermal agent includes one of polydopamine, copper sulfide or indocyanine green; the hydrophilic fiber includes one of polyacrylonitrile (PAN), chitosan, polyvinyl pyrrolidone (PVP), polyvinyl alcohol (PVA) or cellulose acetate. The solvent includes one of N-N dimethylformamide (DMF), ethanol, water, dimethyl sulfoxide (DMSO) or tetrahydrofuran (THF). The hydrophobic fiber includes one of polypropylene (PP), polylactic acid (PLA), polycaprolactone (PCL) or polyurethane (PU).

The present invention also provides a Janus fiber dressing with unidirectional drainage, photothermal evaporation and sterilization functions, the Janus fiber dressing comprising a hydrophobic fiber base layer and a hydrophilic fiber layer with a photothermal agent. The Janus fiber dressing can achieve a unidirectional drainage function of draining water from the hydrophobic layer to the hydrophilic layer; under light, a local high temperature can be generated, the local high temperature is greater than 55°C, which can destroy the bacterial morphology and kill the bacteria, and accelerate the rate of unidirectional drainage by promoting the evaporation rate, as shown in Figure 1.

The present invention also provides an application of a Janus fiber dressing having unidirectional drainage, photothermal evaporation and sterilization functions, wherein the Janus fiber dressing is used for preparing a medicine for promoting wound healing in diabetic patients.

Example 1

This embodiment provides a method for preparing a Janus fiber dressing with unidirectional drainage, photothermal evaporation and sterilization functions, comprising the following steps:

S1: Synthesis of polydopamine nanoparticles (PDA NPs): ethanol and water were mixed (ethanol: water = 20 mL: 45 mL), and then an aqueous ammonia solution (1 mL, 28%-30%) was added to the alcohol/water mixture, stirred at room temperature for 30 min, and finally 130 mg of dopamine hydrochloride was added, stirred and reacted for 30 h to obtain the product. The product was centrifuged, washed three times with a mixed solution of water and ethanol, and vacuum dried at 60° C. overnight to obtain polydopamine (PDA) nanoparticles.

S2: Preparation of PP/PAN _PDA Janus fiber dressing: Janus nanofiber membrane includes two layers of membrane, the outer layer is PAN _PDA fiber membrane, and the inner layer is PP non-woven fabric. 0.28g PAN was dissolved in 3mL DMF to obtain 8wt.% PAN/DMF solution. 0.084g PDA was added to the 8wt.% PAN/DMF solution to prepare spinning solution. PP non-woven fabric was used as the hydrophobic base material, and electrospinning was used to deposit on the PP non-woven fabric, and vacuum dried at 90°C overnight to obtain Janus fiber dressing. Electrospinning parameters: voltage of 8kV, flow rate of 0.04-0.06mm min ^-1 , receiving distance of 10-15cm.

This embodiment also provides a Janus fiber dressing with unidirectional drainage, photothermal evaporation and sterilization functions, and the scanning electron microscope spectrum of the prepared PP/PAN _PDA fiber membrane is shown in Figure 2. As shown in Figure 2a, the diameter of the PP inner layer fiber is (21.741±26)μm, anisotropic, loose and porous. For the PAN _PDA outer layer, the surface of the PAN electrospun fiber without PDA is smooth and the diameter is 104±15nm, as shown in Figure 2b. After the addition of PDA, the fiber surface becomes rougher and the fiber diameter increases to 337nm, as shown in Figure 2c. In addition, all membranes have abundant pore sizes, which is conducive to the discharge of biological fluids, and also proves that the method successfully prepares PP/PAN _PDA fiber membranes with high porosity.

Experimental Example 1

This experimental example provides a unidirectional transport performance test of Janus fiber dressings. By dropping droplets on different sides of Janus fiber dressings, the transport behavior of water on them was studied. The dynamic transport process of droplets on PP/PAN _PDA membranes was monitored by a digital camera. When the hydrophilic layer was placed upward, the droplets were on the hydrophilic layer, and the droplets quickly dispersed on the hydrophilic surface while being blocked by the hydrophobic layer, as shown in Figure 3a. In contrast, once the hydrophobic layer was placed upward and in contact with the droplet, the droplet quickly passed through the hydrophilic surface and wetted the hydrophilic surface within 17s, leaving a dry hydrophobic surface, as shown in Figure 3b. In order to investigate the drainage ability of anti-gravity fluids, the hydrophobic layer was placed below and the droplets dripped from below, as shown in Figure 3c. The droplets spontaneously transported across the membrane from the hydrophobic layer to the hydrophilic layer within 22s, realizing the anti-gravity lifting diffusion phenomenon. Therefore, the hydrophilic PAN _PDA layer can act as a self-pump with anti-gravity drainage ability to discharge excess biological fluids.

Experimental Example 2

In this experimental example, the photothermal heating of Janus fiber dressing was tested, and the temperature rise of Janus fiber dressing was measured by thermal imager. PP/PAN _PDA fiber membranes with different PDA contents were soaked in water for 30s, the membranes were irradiated with 808nm near-infrared laser for 15min, and the temperature changes were recorded by thermal imager. PP/PAN _PDA fiber membranes with different PDA contents were irradiated with 808nm near-infrared laser for 15min, and the temperature changes were recorded by thermal imager, as shown in Figure 4a. Then, the PP/PAN _PDA fiber membranes with different PDA contents were soaked in water for 30s and the temperature changes were measured again. The results are shown in Figure 4b. The pure PP/PAN did not show an obvious heating effect, but the temperature rose rapidly after adding PDA, and the temperature could exceed 55°C. Moreover, as the PDA content increased, the equilibrium temperature would also increase, and it also had a photothermal effect after wetting.

Experimental Example 3

This experimental example provides a rate evaluation test for promoting unidirectional drainage of Janus fiber dressings by photothermal effect. A water tank containing 30g of water was placed on the balance, and the PP/PAN _PDA fiber membrane was suspended so that its lower surface was in contact with the water surface. Subsequently, it was not disturbed for a certain period of time to allow the fiber membrane to absorb water to reach equilibrium. Under 808nm laser irradiation, the weight of the water on the balance was recorded for 60min. After 60min of near-infrared light irradiation, the mass change of the PP/PAN _PDA + laser group was the largest, with a mass decrease of 1.3g·cm ^-2 , and the mass of the PP/PAN _PDA group decreased by 0.6g cm ^-2 . The mass decrease of the PP/PAN _PDA + laser group was 2.17 times that of the PP/PAN _PDA group, as shown in Figure 5a. In addition, the evaporation rate value of the PP/PAN _{30% PDA} + laser group was 1.341g cm ^-2 h ^-1 , which was higher than the 0.674gm ^-2 h ^-1 of the PP/PAN _PDA group, as shown in Figure 5b, showing continuous and stable water evaporation.

Experimental Example 4

This experimental example provides an evaluation of the antibacterial properties of Janus fiber dressings. The antibacterial activity of PP/PAN and PP/PAN _PDA fiber membranes against Staphylococcus aureus (ATCC 25923) and Escherichia coli (ATCC 25922) was determined by plate diffusion method. PP/PAN and PP/PAN _PDA fiber membranes (0.5 cm × 0.5 cm) were sterilized with ultraviolet light before testing. Then, PP/PAN and PP/PAN _PDA fiber membranes were immersed in 2 mL of diluted bacterial suspension with a concentration of 2 × 106 CFU mL ^-1 and then incubated in an oscillating incubator for 30 min. Then, PP/PAN and PP/PAN _PDA were irradiated with 808 near-infrared laser (0.2 W cm ^-2 ) for 0, 5, 10, and 15 min, and oscillated in 4 mL PBS (pH = 7.4) to obtain a bacterial suspension. 50 μL of the bacterial suspension was diluted 100 times and evenly applied to a fresh LB agar plate three times and incubated at 37 °C for 18 h. The unirradiated PBS bacterial suspension was used as a blank sample. The results are shown in Figure 6. In the control group and PP/PAN group, there were a large number of live colonies with complete bacterial morphology and smooth surface. In contrast, the number of colonies decreased sharply after illumination, and the bacterial cell membrane shrank or even burst, indicating that PP/PAN _PDA has a photothermal sterilization effect. When the exposure time increased to 15min, the number of colonies was almost zero and the bacteria no longer had a typical morphology.

Application Example 1

This application example provides an evaluation of the ability of Janus fiber dressing to heal diabetic wounds. Using diabetic wound mice as a model, a circular wound with a diameter of 10 mm was made on the back of each diabetic mouse, and 50 μL (108 CFU mL ^-1 ) of Staphylococcus aureus solution was inoculated to establish an infected wound model. The Janus fiber dressing was applied to the wound of the mouse, and the mouse was treated with photothermal therapy on days 0, 3, and 7. The observation and recording were performed for 18 days. On the 18th day, the wound healing rate of the experimental group was higher than 90%, as shown in Figure 7.

The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the protection scope of the present invention.

Claims (10)

1. A preparation method of Janus fiber dressing with unidirectional drainage, photo-thermal evaporation and sterilization functions is characterized in that ammonia water solution is dissolved in alcohol/water mixture to obtain mixed solution, photo-thermal reagent is dissolved in the mixed solution, and nano particles of the photo-thermal reagent are obtained after drying;

And dissolving the nano particles and the hydrophilic fibers in a solvent to obtain a spinning solution, taking the hydrophobic fibers as a substrate, depositing the spinning solution on the hydrophobic fibers by an electrostatic spinning method, and drying to obtain the Janus fiber dressing with unidirectional drainage, photo-thermal evaporation and sterilization functions.

2. The method for preparing a Janus fiber dressing with unidirectional drainage, photo-thermal evaporation and sterilization functions according to claim 1, wherein the ratio of the addition amounts of photo-thermal agent, hydrophilic fiber and solvent is (0.02-0.10) mg: (0.1-1.0) g (3-10) mL.

3. The preparation method of Janus fiber dressing with unidirectional drainage, photo-thermal evaporation and sterilization functions according to claim 1, wherein the voltage of electrostatic spinning in the electrostatic spinning method is 3-10kV, the speed is 0.01-0.10 mm min ^-1, and the receiving distance is 5-25 cm.

4. The method for preparing the Janus fiber dressing with unidirectional drainage, photo-thermal evaporation and sterilization functions according to claim 1, wherein the photo-thermal reagent comprises one of polydopamine, copper sulfide or indocyanine green;

the hydrophilic fiber comprises one of polyacrylonitrile, chitosan, polyvinylpyrrolidone, polyvinyl alcohol or acetate fiber.

5. The method for preparing a Janus fiber dressing with unidirectional drainage, photo-thermal evaporation and sterilization functions according to claim 1, wherein the solvent comprises one of N-N dimethylformamide, ethanol, water, dimethyl sulfoxide or tetrahydrofuran;

The hydrophobic fiber comprises one of polypropylene, polylactic acid, polycaprolactone, or polyurethane.

6. A Janus fiber dressing having unidirectional drainage, photo-thermal evaporation and sterilization functions according to any of claims 1-5, wherein the Janus fiber dressing comprises a hydrophobic fiber substrate layer and a hydrophilic fiber layer with photo-thermal agents.

7. The Janus fiber dressing with unidirectional drainage, photo-thermal evaporation and sterilization functions according to claim 6, wherein the dressing is capable of achieving a unidirectional drainage function of draining water from a hydrophobic layer to a hydrophilic layer.

8. The Janus fiber dressing with unidirectional drainage, photo-thermal evaporation and sterilization functions according to claim 6, wherein the dressing can generate local high temperature under illumination, and the local high temperature is Wen Dayu ℃.

9. The Janus fiber dressing with unidirectional drainage, photo-thermal evaporation and sterilization functions of claim 8, wherein the localized high temperature is capable of destroying bacterial morphology and killing bacteria and accelerating the rate of unidirectional drainage by promoting the evaporation rate.

10. Use of a Janus fiber dressing having unidirectional drainage, photo-thermal evaporation and sterilization functions according to claim 6, for the preparation of a medicament for promoting wound healing in diabetics.