Conductive nanofiber aerogel for wound repairing and seepage monitoring, raw materials and preparation method

Abstract

The invention belongs to the technical field of medical wound nursing materials, and discloses a conductive nanofiber aerogel for wound repair and seepage monitoring, a raw material and a preparation method, the conductive nanofiber aerogel comprises a matrix and a conductive material dispersed in the matrix; the preparation method comprises the following steps: mixing and stirring deionized water, methacrylated sodium alginate and EDOT to obtain an emulsion, controlling the EDOT in the emulsion to be oxidized into PEDOT, and removing unreacted EDOT and deionized water to obtain the conductive material. Performing liquid nitrogen freezing and freeze drying on the aqueous dispersion in which the nanofiber (containing the first methylacryloyl polymer) and the conductive material are dispersed and the second methylacryloyl polymer is dissolved at the same time to obtain an intermediate product, and initiating double bonds in methylacryloyl groups contained in the intermediate product to perform cross-linking reaction, so as to obtain the conductive nanofiber. The conductive nanofiber aerogel is obtained. The product provided by the invention has good wound repairing and seepage monitoring performance, and can play a high-efficiency role in the field of high-seepage wound application.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of medical wound care materials, and relates to an electrically conductive nanofiber aerogel for wound repair and exudate monitoring, raw materials and a preparation method. BACKGROUND

[0002] Skin, as the largest organ of the human body, is crucial in defending against pathogen invasion and protecting internal organs. Rapid re-epithelialization of damaged skin to restore its structure and function is particularly critical. Modern wound care theory shows that a moderately moist wound environment can accelerate cell migration and proliferation, promote granulation tissue growth and epithelialization, thereby significantly accelerating the healing process. However, excessive exudate from pressure injuries, venous ulcers, and postoperative wounds can quickly saturate traditional dressings, leading to skin maceration, increased infection risk, increased wound tension, and forced opening of healed or sutured wounds, thereby hindering and delaying the healing process. Therefore, the current clinical care strategy often involves frequent dressing changes to maintain an ideal moist environment for high-exudation wounds. However, this not only increases the cost of medical materials and care, but also causes patients pain from frequent dressing changes. Therefore, to improve the maximum exudate absorption saturation of dressings, the development of wound dressings with self-monitoring exudate level function to accurately determine the dressing change point is expected to minimize medical worker intervention and significantly improve the prognosis of high-exudation wounds.

[0003] Due to the structural advantages of nanofiber aerogels, such as biomimetic extracellular matrix structure and nanofiber capillary wicking effect, they are also widely used in the preparation of wound dressings. Compared to aerogel materials without nanofibers, aerogel materials constructed from biomass nanofibers have stronger liquid absorption capacity and strong designability and functionalization potential. Through modification with conductive materials, they can have electrical conductivity and can achieve self-monitoring of exudate levels, showing great potential in the field of high-exudation wound repair.

[0004] PEDOT (poly 3,4-ethylenedioxythiophene) is a high conductivity, non-toxic conductive polymer, but itself is hydrophobic, usually PSS (polystyrene sulfonic acid) is used as a dopant and dispersant to enable it to be stably dispersed in water, but the introduction of PSS makes the dispersion system acidic, which is not conducive to cell survival and proliferation, and may also trigger an inflammatory response, and PEDOT:PSS lacks crosslinking sites, limiting its firm loading in the bulk structure of fiber aerogel, for example, the patent application with the application publication number CN120118386A discloses a kind of nano-porous aerogel based on carboxymethyl chitosan and its preparation method and application, its preparation method is to mix carboxymethyl chitosan, carboxylated multi-walled carbon nanotube and glutaraldehyde, freeze and freeze-drying to prepare CMC / C-CNT aerogel, then the CMC / C-CNT aerogel is placed in PEDOT:PSS / dimethyl sulfoxide solution Vacuum impregnation and vacuum drying, obtain PEDOT:PSS@CMC / C-CNT conductive aerogel with internal and external double conductive network, however, the PEDOT:PSS conductive material used by it lacks adhesion to the CMC / C-CNT aerogel matrix material.

[0005] Therefore, based on the actual needs of current wound care and the limitations of existing materials, it is necessary to develop a new type of conductive material based on PEDOT. This material should have crosslinking sites to ensure its firm loading in the bulk structure of fiber aerogel; at the same time, it should have excellent water dispersibility and biological safety to meet the actual requirements of wound repair and exudate monitoring. The application of this new type of conductive material in the preparation of conductive nanofiber aerogel for wound repair and exudate monitoring will bring new breakthroughs and hopes for the treatment of high exudation wounds. SUMMARY

[0006] The purpose of the present application is to solve the problems existing in the prior art and provide a conductive nanofiber aerogel for wound repair and exudate monitoring, raw materials and preparation method.

[0007] To achieve the above-mentioned purpose, the technical scheme adopted by the present application is as follows:

[0008] A kind of conductive material, which is a micellar particle with PEDOT as the core and methacrylated sodium alginate as the shell.

[0009] The conductive material of the present application has crosslinking sites, i.e. the exposed methacryl groups in the molecular structure of the methacrylated sodium alginate shell. Under ultraviolet light irradiation, the addition of a photoinitiator (such as Irgacure 2959) can initiate the crosslinking of the double bonds of the methacryl groups, forming a stable crosslinked network.

[0010] The conductive material of the present application has excellent water dispersibility, because the methacrylated sodium alginate shell has hydrophilicity, enabling the micellar particle to be stably dispersed in water.

[0011] The conductive material of the present application has excellent biosafety, because the methylacrylated sodium alginate shell is a derivative of natural sodium alginate, and has excellent biocompatibility and biodegradability.

[0012] The conductive material of the present application has excellent conductive performance, which is mainly attributed to the PEDOT component therein. PEDOT is a conductive polymer with excellent performance, which is formed by oxidative polymerization of EDOT (3,4-ethylenedioxythiophene monomer). PEDOT has a conjugated structure with single and double bonds alternatingly connected, and this unique conjugated polymer main chain provides an effective channel for the migration of electric charges. In the process of p-type doping, positive charge defects that can be delocalized are generated on the chain, and these charge carriers can move along the chain and between chains under the action of an external electric field, thereby endowing the conductive material with excellent conductive performance.

[0013] The present application also provides a method for preparing the conductive material as described above. After mixing and stirring deionized water, methylacrylated sodium alginate and EDOT to obtain an emulsion, the EDOT in the emulsion is controlled to be oxidized into PEDOT, and then dialysis, freezing and freeze-drying are sequentially performed to remove the unreacted EDOT and deionized water therein, so as to obtain the conductive material.

[0014] Compared with the conventional dopant PSS, the methylacrylated sodium alginate is a biocompatible high molecular material obtained by modifying natural sodium alginate through methacrylation, which is beneficial to the survival and proliferation of cells and is not easy to cause inflammatory reactions. In addition, the molecular chain contains a methacryl group and a carboxyl group, wherein the methacryl group has photo-crosslinking activity and can provide crosslinking sites. The carboxyl group can form a negatively charged carboxylate after dissociation, causing PEDOT and methylacrylated sodium alginate to approach each other through electrostatic attraction, thereby forming a preliminary aggregate. This electrostatic interaction is a common driving force in high molecular composite systems. In this case, the hydrophobic conjugated chain of PEDOT is aggregated inside the hydrophilic methylacrylated sodium alginate through π-π interaction, forming a micellar structure, and generating a micellar particle with PEDOT as the core and methylacrylated sodium alginate as the shell.

[0015] As a preferred technical solution:

[0016] The method as described above, the viscosity of the methylacrylated sodium alginate is 300 mPa·s, and the degree of substitution of the methacryl group in the methylacrylated sodium alginate is 40%.

[0017] The mass ratio of EDOT to the methacrylated sodium alginate is 1:0.5-2, which is conducive to achieving a balance between the stability and conductivity of the conductive material and ensuring that the number of exposed methacryl groups is sufficient, and the mass ratio of EDOT to deionized water is 1:50-100; the stirring rate is 8000-15000 rpm, and the time is 10-30 min.

[0018] The method as described above, the control of the oxidation of EDOT to PEDOT in the emulsion refers to adding an oxidizing agent (a persulfate salt, including one of sodium persulfate and ammonium persulfate) to the emulsion, and then stirring the reaction for 24-48 h; the mass ratio of EDOT to the oxidizing agent is 1:0.5-2.5.

[0019] The application also provides a conductive nanofiber aerogel for wound repair and exudate monitoring, which comprises a base body and a conductive material dispersed in the base body.

[0020] The base body is composed of nanofibers and a second methacrylated polymer, the nanofibers contain a first methacrylated polymer, and the nanofibers are staggered and overlapped to form a three-dimensional skeleton, and the overlapping parts are wrapped by the second methacrylated polymer.

[0021] The conductive material, the nanofibers and the second methacrylated polymer are crosslinked with each other to form a stable three-dimensional structure.

[0022] The mass ratio of the nanofibers, the second methacrylated polymer and the conductive material is 10:1-20:5-20.

[0023] The conductive material is one of the conductive materials as described above.

[0024] The conductive material, the second methacrylated polymer and the nanofibers in the base body all contain methacryl groups, and a stable crosslinked network can be formed after the crosslinking reaction of the three, which significantly improves the load stability of the conductive material in the base body.

[0025] If the second methacrylated polymer is not added, the conductive material is more inclined to self-crosslinking than crosslinking with the nanofibers during the crosslinking reaction due to the limited number of methacryl groups in the nanofibers, which is not conducive to improving the load stability of the conductive material in the base body.

[0026] In addition, the mass ratio of the nanofiber, the second methacrylated polymer and the conductive material is 10:1-20:5-20, so as to form an interconnected three-dimensional conductive network in the conductive nanofiber aerogel. If the interconnected three-dimensional conductive network is not formed in the conductive nanofiber aerogel, the initial conductivity is zero. When the wound exudate permeates to a certain critical threshold, the conductive nanofiber aerogel shows measurable conductivity, but the quantitative relationship between the conductivity and the water content below the threshold is not clear, which limits the comprehensiveness of the exudate monitoring. Therefore, constructing a stable interconnected three-dimensional conductive network in the conductive nanofiber aerogel is the key to improving the exudate sensing sensitivity and monitoring accuracy, and is of great significance for developing an efficient wound exudate monitoring system.

[0027] The conductive nanofiber aerogel has a wound repair function, because on the one hand, the raw materials selected by the application have excellent hydrophilicity, and on the other hand, the internal nanofibers of the conductive nanofiber aerogel of the application are staggered and overlapped to form a rich micro-meso-macro pore structure, which is conducive to enhancing the driving action of the capillary force on the rapid transportation of water. The dual action makes the conductive nanofiber aerogel have intrinsic hydrophilicity and excellent liquid absorption performance, and can maintain the moist environment required for wound healing.

[0028] The conductive nanofiber aerogel also has an exudate self-monitoring function, because the excellent hydrophilic performance of the conductive nanofiber aerogel for wound repair and exudate monitoring allows exudate to enter its internal pores. When the conductive nanofiber aerogel absorbs the exudate inward, a new ion migration path is established, which is parallel to the original electronic conductive network, thereby causing the resistance of the conductive nanofiber aerogel to decrease. Therefore, the application can monitor the resistance value of the conductive nanofiber aerogel in real time, and evaluate the wound exudate level according to the functional relationship between the resistance value of the aerogel and the water content.

[0029] As a preferred technical solution:

[0030] The conductive nanofiber aerogel for wound repair and exudate monitoring as described above, the first methacrylated polymer is one or more of methacrylated gelatin, methacrylated silk fibroin, and the substitution degree of the methacryl group in the first methacrylated polymer is 40-90%;

[0031] The second methacrylated polymer is one or more of methacrylated gelatin, methacrylated sodium alginate and methacrylated chitosan, and the substitution degree of the methacryl group in the second methacrylated polymer is 30-90%;

[0032] The first methacrylated polymer and the second methacrylated polymer are both derivatives of natural biopolymers such as gelatin, chitosan and sodium alginate, which have excellent biocompatibility and biodegradability.

[0033] The conductive nanofiber aerogel for wound repair and exudate monitoring has a porosity of ≥98%, a density of ≤20 mg / cm 3 , an electrical conductivity of 0.1-0.2 S / m, a static contact angle of ≤50°, a liquid absorption rate of ≥4000%, and a cell survival rate of ≥90%.

[0034] The application also provides a method for preparing the conductive nanofiber aerogel for wound repair and exudate monitoring, which comprises the following steps: freezing a water dispersion liquid containing nanofibers, a conductive material and a second methacrylated polymer in liquid nitrogen (for 5-30 min) and freeze-drying (the freeze-drying time needs to be determined according to the thickness of the frozen sample, that is, the freeze-drying time needs to be longer when the thickness of the frozen sample is thicker, and the freeze-drying time needs to be relatively shorter when the thickness of the frozen sample is thinner), to obtain an intermediate product, and then initiating a crosslinking reaction of the double bonds in the methacryl groups contained in the intermediate product, to obtain the conductive nanofiber aerogel for wound repair and exudate monitoring.

[0035] During the liquid nitrogen freezing process, the conductive material is pushed and interpenetrated and entangled by the growing ice crystals, and finally forms an interconnected three-dimensional conductive network.

[0036] As a preferred technical solution:

[0037] The method comprises the following steps: the water dispersion liquid is prepared by the following steps: the electrospun nanofiber crosslinked membrane is cut into pieces, mixed with deionized water and homogenized (the homogenization speed is 8000-15000 rpm, the homogenization time is 10-30 min, and the concentration of the system after homogenization is 5-20 mg / mL), then the second methacrylated polymer and the conductive material are mixed and dispersed (for 1-2 h), and the water dispersion liquid is obtained.

[0038] The method comprises the following steps: the electrospun nanofiber crosslinked membrane is prepared by the following steps: the first methacrylated polymer, polylactic acid and a solvent (hexafluoroisopropanol) are stirred and uniformly mixed to prepare a spinning solution, the electrospun nanofiber membrane is prepared by electrospinning, and the electrospun nanofiber membrane is subjected to pre-crosslinking, to obtain the electrospun nanofiber crosslinked membrane.

[0039] The method comprises the following steps: the electrospun nanofiber crosslinked membrane is prepared by the following steps: the first methacrylated polymer, polylactic acid and a solvent (hexafluoroisopropanol) are stirred and uniformly mixed to prepare a spinning solution, the electrospun nanofiber membrane is prepared by electrospinning, and the electrospun nanofiber membrane is subjected to pre-crosslinking, to obtain the electrospun nanofiber crosslinked membrane.

[0040] The process parameters of electrospinning include: the injection speed of the spinning solution is 1-2.5 mL / h, the spinning voltage is 10-20 kV, the receiving distance is 10-20 cm, the ambient temperature is 25±1℃, the ambient relative humidity is 40-70%, and the rotating drum collector rotates at a speed of 200-1000 rpm;

[0041] The pre-crosslinking is performed by immersing the electrospun nanofiber membrane in a photoinitiator solution, and then the electrospun nanofiber membrane is irradiated with ultraviolet light, followed by washing (alternately using ethanol and deionized water) and normal pressure drying;

[0042] The photoinitiator solution is composed of a photoinitiator (such as photoinitiator I2959) and anhydrous ethanol, and the concentration of the photoinitiator solution is 10-20 mg / mL;

[0043] The mass-volume ratio of the electrospun nanofiber membrane to the photoinitiator solution is 1 g:50-200 mL;

[0044] The distance between the ultraviolet light source and the electrospun nanofiber membrane is 5-15 cm;

[0045] The irradiation intensity of the ultraviolet light is 1-10 mW / cm 2 , the irradiation wavelength is 365 nm, and the irradiation time is 10-30 min.

[0046] The method as described above, which initiates the crosslinking reaction of the double bond in the methacryl group contained in the intermediate product, is performed by immersing the intermediate product in a photoinitiator solution, irradiating it with ultraviolet light using an ultraviolet light source, and then sequentially performing washing (alternately using ethanol and deionized water), liquid nitrogen freezing, and freeze-drying;

[0047] The photoinitiator solution is composed of a photoinitiator (such as photoinitiator I2959) and anhydrous ethanol, and the concentration of the photoinitiator solution is 1-10 mg / mL;

[0048] The mass-volume ratio of the intermediate product to the photoinitiator solution is 1 g:50-200 mL;

[0049] The distance between the ultraviolet light source and the intermediate product is 5-15 cm;

[0050] The irradiation intensity of the ultraviolet light is 1-10 mW / cm 2 , the irradiation wavelength is 365 nm, and the irradiation time is 10-30 min.

[0051] Advantages:

[0052] (1) The present application uses methacrylated gelatin and polylactic acid as raw materials for composite electrospinning, and the pre-crosslinking process gives the nanofiber membrane strong water stability, avoiding the use of organic solvents (such as tert-butyl alcohol) in the homogenization process; in addition, the residual double bonds on the surface of the nanofiber can also provide crosslinking sites for the formation of nanofiber aerogel.

[0053] (2) The present application introduces a specific proportion of high biocompatibility methacrylated polymer into the fiber dispersion liquid, induces the methacrylated polymer to condense along the long axis of the nanofiber capillary by freeze-drying, and then drives the in-situ gelation of the methacrylated polymer by photo-crosslinking to "bond" the mutually overlapped nanofibers, realizing the controllable formation of nanofiber aerogel without toxic crosslinking agent.

[0054] (3) The methacrylated sodium alginate doped PEDOT conductive material of the present application has excellent photo-crosslinking activity, conductivity, biocompatibility and water dispersibility, and can be loaded into the nanofiber aerogel matrix in-situ by one-step photo-crosslinking as a high-performance conductive material, improving the stability of the conductive material loading and avoiding the cumbersome conductive material modification process. At the same time, the conductive material forms an interconnected conductive network in the nanofiber aerogel, giving the nanofiber aerogel conductivity. In addition, the biocompatibility of the material makes the nanofiber aerogel suitable for medical wound care.

[0055] (4) Based on the intrinsic electronic conductivity and hydrophilic properties of the conductive nanofiber aerogel, when the conductive nanofiber aerogel absorbs exudate inward, a new ion migration path is established, which is parallel to the original PEDOT electronic conductive network, thus leading to a decrease in the resistance of the conductive nanofiber aerogel. By monitoring the resistance value of the conductive nanofiber aerogel in real time and evaluating the wound exudate level according to the functional relationship between the resistance value of the aerogel and the water content, the conductive nanofiber aerogel is endowed with exudate sensing ability.

[0056] (5) The present application selects methacrylated polymer, polylactic acid and EDOT as raw materials, and realizes the synergistic effect among the components through optimized design, avoiding the defects of single material. The designed conductive nanofiber aerogel has high conductivity, excellent hydrophilicity, and also has biocompatibility and exudate monitoring function, which can meet the clinical needs of high exudation wound repair.

[0057] (6) The conductive nanofiber aerogel prepared by the present application for wound repair and exudate monitoring shows good conductivity, hydrophilicity, biocompatibility, and also has the stability of conductive material loading and exudate monitoring performance, which can play an efficient role in the field of high exudation wound application. BRIEF DESCRIPTION OF DRAWINGS

[0058] Figure 1A schematic diagram of the conductive nanofiber aerogel for wound repair and exudate monitoring of the present application;

[0059] Figure 2 A schematic diagram of the conductive nanofiber aerogel for wound repair and exudate monitoring of Example 1 of the present application using mouse fibroblasts (L929) to test the cell survival rate; in the figure, (a) is the live / dead staining image of mouse fibroblasts (L929) in the negative control group, (b) is the live / dead staining image of mouse fibroblasts (L929) in the experimental group, and (c) is the cell survival rate of L929 cells;

[0060] Wherein, 1-nanofiber, 2-second methacrylated polymer, 3-conductive material. DETAILED DESCRIPTION

[0061] The present application will be further described in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present application and not to limit the scope of the present application. In addition, it should be understood that after reading the content taught by the present application, those skilled in the art can make various modifications or changes to the present application, and these equivalent forms also fall within the scope defined by the appended claims of the present application.

[0062] To ensure that the properties of the substances used in each example and comparative example are fully disclosed, the manufacturer and brand of the substance are specified. Other products from other manufacturers and brands that meet the definition of the present application are also feasible.

[0063] The test methods for the relevant performance indicators in each of the following examples and comparative examples are as follows:

[0064] Porosity: the nanofiber aerogel prepared in each example and comparative example is used as a sample, and then the aerogel skeleton density (p 骨架 , g / cm 3 ) and the aerogel density (p, g / cm 3 ) of the sample are obtained, and then the porosity (P, %) of the sample is calculated according to the measured results. The calculation formula of the porosity is: The calculation formula of the aerogel skeleton density is: In the formula, w represents the mass percentage.

[0065] Conductivity: the nanofiber aerogel prepared in each example and comparative example is used as a sample, and then the conductivity of the sample is measured by a digital multimeter (Keithley DMM6500). The specific steps are as follows: first, measure the cross-sectional area (A, m 2) and thickness (L, m), then the double probes of the digital multimeter were connected to the top / bottom surface of the aerogel through conductive silver glue, the aerogel resistance (R, Ω) was measured, and finally the conductivity (K, S / m) was calculated according to the measured data, and the calculation formula was:

[0066] Static contact angle: the nanofiber aerogel prepared in each example and comparative example was taken as a sample, and then the static contact angle of the sample was tested by using a contact angle measuring instrument (Kino SL200B) with 5 μL deionized water droplets.

[0067] Liquid absorption rate: the nanofiber aerogel prepared in each example and comparative example was taken as a sample, and then the sample's adsorption capacity was tested by recording the weight change of the sample before and after soaking in deionized water for a specific time. The specific steps were as follows: first, the weight of the dried sample W1 (unit: g) was measured, then the sample was immersed in deionized water for 10 seconds, removed, and the excess water on the surface of the wet gel was absorbed with filter paper, and then weighed W2 (unit: g), finally the water absorption rate W w (unit: %) was calculated according to the measured data, and the calculation formula was:

[0068] Conductive material firmness: the nanofiber aerogel prepared in each example and comparative example was taken as a sample, and then the sample was placed in a deionized water solution and ultrasonicated (ultrasonic power 100 W) for 30 min, and whether PEDOT was dissolved out was observed.

[0069] Cell survival rate: the nanofiber aerogel prepared in each example and comparative example was taken as a sample, and then mouse fibroblasts (i.e. L929 cells) were used to evaluate the biocompatibility of the nanofiber aerogel, and the specific test process was as follows:

[0070] (a) first sterilize the sample by ultraviolet irradiation for 1 hour, then immerse the sterilized sample in a 37℃ DMEM culture solution for 24 hours to prepare an extraction solution, after the extraction solution is filtered through a 0.22 μm sterile filter, add fetal bovine serum (FBS) (volume concentration of 10%) and penicillin / streptomycin (volume concentration of penicillin is 1%) to prepare a nanofiber aerogel extraction solution with a concentration of 10 mg / mL;

[0071] (b) inoculate L929 fibroblasts into a 24-well plate (1 mL per well) at a density of 2×10 4 cells / mL, and culture at 37℃, 5% CO2 for 12 hours to adhere, then discard the old culture medium, replace it with the nanofiber aerogel extraction solution, and continue to culture for 72 hours;

[0072] (c) The nanofiber aerogel extract after the end of culture was used as the experimental group, and then the cell morphology was observed by Calcein-AM / PI fluorescence staining and fluorescence microscopy. Cells cultured in medium without the addition of the extract were used as the negative control group. Finally, five different fields were randomly selected, and the number of living cells (Q 活 ) and dead cells (Q 死 ) after 72 hours of culture was counted using Image J software, and the survival rate V (%) of L929 cells was calculated according to the formula:

[0073] Example 1

[0074] A method for preparing an electrically conductive nanofiber aerogel for wound repair and exudate monitoring, comprising the following steps:

[0075] (1) Preparation of raw materials;

[0076] Deionized water;

[0077] Methacrylated sodium alginate: The manufacturer is Suzhou Yongqinquan Intelligent Equipment Co., Ltd., the brand is EFL-AlgMA-300k, and the viscosity is 300 mPa·s. The degree of substitution of the methacryl group is 40%;

[0078] EDOT;

[0079] Oxidizing agent: ammonium persulfate;

[0080] First methacrylated polymer: methacrylated gelatin, the manufacturer is Suzhou Yongqinquan Intelligent Equipment Co., Ltd., the product number is EFL-GM-90, and the degree of substitution of the methacryl group is 90%;

[0081] Polylactic acid: The manufacturer is Shanghai Maikelin Biochemical Technology Co., Ltd., and the product number is P875107;

[0082] Solvent: hexafluoroisopropanol;

[0083] Photoinitiator solution A: composed of photoinitiator I2959 and anhydrous ethanol, with a concentration of 15 mg / mL;

[0084] Second methacrylated polymer: methacrylated gelatin, the manufacturer is Suzhou Yongqinquan Intelligent Equipment Co., Ltd., the product number is EFL-GM-90, and the degree of substitution of the methacryl group is 90%;

[0085] Photoinitiator solution B: composed of photoinitiator I2959 and anhydrous ethanol, with a concentration of 5 mg / mL;

[0086] (2) Preparation of conductive material;

[0087] (2.1) mixing deionized water, methacrylated sodium alginate and EDOT and stirring at a speed of 10000 rpm for 20 min to obtain an emulsion; wherein the mass ratio of EDOT to methacrylated sodium alginate is 1:1, and the mass ratio of EDOT to deionized water is 1:65;

[0088] (2.2) adding an oxidizing agent to the emulsion, stirring for 32 h, and then sequentially performing dialysis, freezing and freeze-drying to remove unreacted EDOT and deionized water therein, to obtain the conductive material; wherein the mass ratio of EDOT to the oxidizing agent in the emulsion is 1:2;

[0089] The finally prepared conductive material is a micellar particle with PEDOT as the core and methacrylated sodium alginate as the shell;

[0090] (3) preparing an electrospun nanofiber crosslinked membrane;

[0091] (3.1) mixing the first methacrylated polymer, polylactic acid and a solvent to prepare a spinning solution with a concentration of 120 mg / mL, and preparing an electrospun nanofiber membrane by electrospinning; wherein the mass ratio of the first methacrylated polymer to polylactic acid is 10:10;

[0092] The process parameters of electrospinning include: the injection speed of the spinning solution is 2 mL / h, the spinning voltage is 15 kV, the receiving distance is 15 cm, the environmental temperature is 25°C, the environmental relative humidity is 60%, and the rotating drum collector rotates at a speed of 200 rpm;

[0093] (3.2) immersing the electrospun nanofiber membrane in the photoinitiator solution A, and irradiating it with ultraviolet light source, and then sequentially performing washing and normal pressure drying, to obtain the electrospun nanofiber crosslinked membrane; wherein the mass-volume ratio of the electrospun nanofiber membrane to the photoinitiator solution A is 1 g:100 mL, the distance between the ultraviolet light source and the electrospun nanofiber membrane is 10 cm, the irradiation intensity of the ultraviolet light is 6 mW / cm 2 , the irradiation wavelength is 365 nm, and the irradiation time is 20 min;

[0094] (4) preparing a water dispersion;

[0095] After the electrospun nanofiber crosslinked membrane is cut and mixed with deionized water, the second methacrylated polymer and the conductive material prepared in step (2) are added and dispersed for 1.5 h, to obtain the water dispersion; wherein the homogenization speed is 10000 rpm, the homogenization time is 20 min, the concentration of the system after homogenization is 5 mg / mL, and the mass ratio of the nanofiber, the second methacrylated polymer and the conductive material is 10:10:10;

[0096] (5) freeze the water dispersion in liquid nitrogen and freeze dry to obtain an intermediate product; wherein the freezing time in liquid nitrogen is 30 min;

[0097] (6) immerse the intermediate product in the photoinitiator solution B, and then irradiate it with ultraviolet light, and then sequentially wash, freeze in liquid nitrogen and freeze dry to obtain the electrically conductive nanofiber aerogel for wound repair and exudate monitoring; wherein the mass-volume ratio of the intermediate product to the photoinitiator solution B is 1 g: 100 mL, the distance between the ultraviolet light source and the intermediate product is 10 cm, the irradiation intensity of the ultraviolet light is 6 mW / cm 2 , the irradiation wavelength is 365 nm, the irradiation time is 20 min, and the freezing time in liquid nitrogen is 20 min.

[0098] The electrically conductive nanofiber aerogel for wound repair and exudate monitoring finally prepared comprises a matrix and electrically conductive material 3 dispersed in the matrix;

[0099] The matrix is composed of nanofibers 1 and a second methacrylated polymer 2, the nanofibers contain a first methacrylated polymer, the nanofibers are staggered and overlapped to form a three-dimensional skeleton, and the overlapped parts are wrapped by the second methacrylated polymer;

[0100] The electrically conductive material, the nanofibers and the second methacrylated polymer are crosslinked with each other to form a stable three-dimensional structure;

[0101] The electrically conductive nanofiber aerogel for wound repair and exudate monitoring has a porosity of 99%, a density of 13 mg / cm 3 , a conductivity of 0.12 S / m, a static contact angle of 20°, a liquid absorption rate of 4200%, no electrically conductive material dissolution, and a cell survival rate of 95.1%. The cell survival rate is shown in Figure 2 The results show that the survival rate of L929 cells cultured in the leaching liquor of the electrically conductive nanofiber aerogel for wound repair and exudate monitoring (i.e. the experimental group) has no significant difference from the survival rate of L929 cells cultured in the complete culture medium (i.e. the control group), indicating that the electrically conductive nanofiber aerogel of Example 1 has excellent cell compatibility.

[0102] Comparative Example 1

[0103] A method for preparing an electrically conductive nanofiber aerogel for wound repair and exudate monitoring, which is basically the same as Example 1, except that the methacrylated sodium alginate in steps (1) to (2) is replaced by an equal amount of PSS;

[0104] The finally prepared electrically conductive material is a micellar particle with PEDOT as the core and PSS as the shell.

[0105] The conductive material used in step (4) is prepared in this comparative example.

[0106] The final conductive nanofiber aerogel for wound repair and exudate monitoring is basically the same as in Example 1, except that the conductive material is prepared in this comparative example. Since PSS does not have a methacryl group, it cannot be cross-linked with the nanofiber and the second methacrylated polymer.

[0107] The conductivity of the conductive nanofiber aerogel for wound repair and exudate monitoring is 0.06 S / m, the cell survival rate is 80%, and the conductive material is dissolved out.

[0108] Comparing Comparative Example 1 and Example 1, the conductivity and cell survival rate of the conductive nanofiber aerogel prepared in this comparative example are reduced. This is because PSS does not have a methacryl group and cannot be cross-linked with the nanofiber and the second methacrylated polymer, resulting in partial dissolution of the conductive material in step (6) and a decrease in the conductivity of the aerogel system. In addition, the biocompatibility of PSS is not as good as that of methacrylated sodium alginate, which also leads to a decrease in the cell survival rate of the cells cultured with this material.

[0109] Comparative Example 2

[0110] A method for preparing a conductive nanofiber aerogel for wound repair and exudate monitoring is basically the same as in Example 1, except that the first methacrylated polymer in step (3.1) is replaced with an equal amount of polylactic acid.

[0111] The electrospun nanofiber cross-linked membrane used in step (4) is prepared in this comparative example.

[0112] The final conductive nanofiber aerogel for wound repair and exudate monitoring is basically the same as in Example 1, except that the nanofiber does not contain the first methacrylated polymer, and the hydrophobicity of the nanofiber is enhanced, resulting in a decrease in the hydrophilicity of the conductive nanofiber aerogel.

[0113] The density of the conductive nanofiber aerogel for wound repair and exudate monitoring is 25 mg / cm 3 , the static contact angle is 80°, the liquid absorption rate is 3000%, and the cell survival rate is 85%.

[0114] Comparative Example 2 and Example 1 can be compared, the density of the nanofiber aerogel prepared in this comparative example increases, the static contact angle and the liquid absorption performance deteriorate, and the cell survival rate slightly decreases. This is because the first methacrylated polymer is replaced with an equal amount of polylactic acid, and the polylactic acid nanofiber film obtained exhibits strong hydrophobicity. When the polylactic acid nanofiber film is cut and mixed with deionized water to be homogeneous, the hydrophobicity of polylactic acid will seriously affect the stability of the nanofiber dispersion. In the liquid nitrogen freezing step, the nanofiber and water are layered and agglomerated, resulting in an increase in the density of the nanofiber aerogel after freeze-drying. Secondly, the large proportion of hydrophobic polylactic acid nanofiber leads to an increase in the static contact angle and a decrease in the liquid absorption performance of the obtained nanofiber aerogel. In addition, since polylactic acid is also a cell compatible material, lactic acid and other acidic products will be produced after the degradation of polylactic acid, resulting in a decrease in the pH of the leaching solution in the culture medium, and a slight decrease in the cell survival rate.

[0115] Comparative Example 3

[0116] A method for preparing an electrically conductive nanofiber aerogel for wound repair and exudate monitoring, which is basically the same as Example 1, except that the second methacrylated polymer in step (4) is replaced with an equal amount of the conductive material prepared in step (2).

[0117] The final electrically conductive nanofiber aerogel for wound repair and exudate monitoring has a static contact angle of 60°, a liquid absorption rate of 3000%, a cell survival rate of 85%, and a conductive material dissolves out.

[0118] Comparing Comparative Example 3 and Example 1, the static contact angle of the electrically conductive nanofiber aerogel prepared in this comparative example increases, the liquid absorption rate decreases, and the cell survival rate slightly decreases. This is because the second methacrylated polymer has excellent hydrophilic properties, and when it is replaced with an equal amount of the conductive material prepared in step (2), the proportion of methacrylated polymer decreases, resulting in a decrease in hydrophilicity and a decrease in biocompatibility, and a slight decrease in cell survival rate. In addition, the conductive material has sufficient methacryl groups, and the nanofiber has been pre-crosslinked, leaving fewer methacryl groups. If the methacrylated biopolymer used to weld the nanofiber is not added, the conductive material will tend to self-crosslink under the action of the photoinitiator and 365 nm light, rather than crosslinking with the matrix, which is not conducive to the firm loading of the conductive material in the nanofiber aerogel structure.

[0119] Example 2

[0120] A method for preparing an electrically conductive nanofiber aerogel for wound repair and exudate monitoring, the steps are as follows:

[0121] (1) Preparation of raw materials;

[0122] Deionized water;

[0123] Methacrylated sodium alginate: the manufacturer is Suzhou Yongqinquan Intelligent Equipment Co., Ltd., the brand is EFL-AlgMA-300k, the viscosity is 300 mPa·s, and the degree of substitution of the methacryl group is 40%;

[0124] EDOT;

[0125] Oxidant: ammonium persulfate;

[0126] First methacrylated polymer: methacrylated gelatin, the manufacturer is Suzhou Yongqinquan Intelligent Equipment Co., Ltd., the product number is EFL-GM-90, and the degree of substitution of the methacryl group is 90%;

[0127] Polylactic acid: the manufacturer is Shanghai Maikelin Biochemical Technology Co., Ltd., and the product number is P875107;

[0128] Solvent: hexafluoroisopropanol;

[0129] Photoinitiator solution A: composed of photoinitiator I2959 and anhydrous ethanol, and the concentration is 20 mg / mL;

[0130] Second methacrylated polymer: methacrylated gelatin, the manufacturer is Suzhou Yongqinquan Intelligent Equipment Co., Ltd., the product number is EFL-GM-90, and the degree of substitution of the methacryl group is 90%;

[0131] Photoinitiator solution B: composed of photoinitiator I2959 and anhydrous ethanol, and the concentration of the photoinitiator solution is 10 mg / mL;

[0132] (2) Preparing the conductive material;

[0133] (2.1) Mixing deionized water, methacrylated sodium alginate and EDOT and stirring at a speed of 15000 rpm for 30 min to obtain an emulsion; wherein the mass ratio of EDOT to methacrylated sodium alginate is 1:0.5, and the mass ratio of EDOT to deionized water is 1:100;

[0134] (2.2) Adding an oxidant to the emulsion, stirring for 24 h, and then sequentially performing dialysis, freezing and freeze-drying to remove unreacted EDOT and deionized water therein, to obtain the conductive material; wherein the mass ratio of EDOT to the oxidant in the emulsion is 1:2;

[0135] The finally prepared conductive material is a micellar particle with PEDOT as the core and methacrylated sodium alginate as the shell;

[0136] (3) Preparing the electrospun nanofiber crosslinked film;

[0137] (3.1) The first methacrylated polymer, polylactic acid, and solvent are stirred and mixed to prepare a spinning solution with a concentration of 100 mg / mL, and an electrostatic nanofiber membrane is prepared by electrospinning; wherein the mass ratio of the first methacrylated polymer to the polylactic acid is 10:20;

[0138] The process parameters of electrospinning include: the injection speed of the spinning solution is 1 mL / h, the spinning voltage is 10 kV, the receiving distance is 10 cm, the environmental temperature is 24℃, the environmental relative humidity is 40%, and the rotating drum collector rotates at a speed of 500 rpm;

[0139] (3.2) The electrospun nanofiber membrane is immersed in the photoinitiator solution A, and is subjected to ultraviolet light irradiation using an ultraviolet light source, and is then sequentially washed and dried at normal pressure to obtain an electrospun nanofiber crosslinked membrane; wherein the mass-volume ratio of the electrospun nanofiber membrane to the photoinitiator solution A is 1 g:50 mL, the distance between the ultraviolet light source and the electrospun nanofiber membrane is 15 cm, the irradiation intensity of the ultraviolet light irradiation is 1 mW / cm 2 , the irradiation wavelength is 365 nm, and the irradiation time is 10 min;

[0140] (4) Preparation of a water dispersion;

[0141] The electrospun nanofiber crosslinked membrane is cut and mixed with deionized water to obtain a homogeneous mixture, and then the second methacrylated polymer and the conductive material prepared in step (2) are added and mixed and dispersed for 1 h to obtain a water dispersion; wherein the homogenization speed is 15000 rpm, the homogenization time is 30 min, the concentration of the system after homogenization is 5 mg / mL, and the mass ratio of the nanofiber, the second methacrylated polymer, and the conductive material is 10:20:5;

[0142] (5) The water dispersion is subjected to liquid nitrogen freezing and freeze-drying to obtain an intermediate product; wherein the liquid nitrogen freezing time is 30 min;

[0143] (6) The intermediate product is immersed in the photoinitiator solution B, and is subjected to ultraviolet light irradiation using an ultraviolet light source, and is then sequentially washed, subjected to liquid nitrogen freezing, and freeze-dried to obtain a conductive nanofiber aerogel for wound repair and exudate monitoring; wherein the mass-volume ratio of the intermediate product to the photoinitiator solution B is 1 g:200 mL, the distance between the ultraviolet light source and the intermediate product is 5 cm, the irradiation intensity of the ultraviolet light irradiation is 10 mW / cm 2 , the irradiation wavelength is 365 nm, the irradiation time is 30 min, and the liquid nitrogen freezing time is 30 min.

[0144] The conductive nanofiber aerogel for wound repair and exudate monitoring finally prepared, as shown in FIG. Figure 1 , includes a base body and a conductive material 3 dispersed in the base body;

[0145] The matrix is composed of nanofibers 1 containing a first methacrylated polymer and a second methacrylated polymer 2, the nanofibers 1 being staggered and overlapping to form a three-dimensional skeleton, the overlapping places being wrapped by the second methacrylated polymer 2;

[0146] The electrically conductive material 3, the nanofibers 1 and the second methacrylated polymer 2 are crosslinked with each other to form a stable three-dimensional structure;

[0147] The electrically conductive nanofiber aerogel for wound repair and exudate monitoring has a porosity of 99%, a density of 15 mg / cm 3 , an electrical conductivity of 0.1 S / m, a static contact angle of 0°, a liquid absorption rate of 4500%, a cell survival rate of 93%, and no dissolution of the electrically conductive material.

[0148] Example 3

[0149] A preparation method of an electrically conductive nanofiber aerogel for wound repair and exudate monitoring, comprising the following steps:

[0150] (1) Preparation of raw materials;

[0151] Deionized water;

[0152] Methacrylated sodium alginate: the manufacturer is Suzhou Yongqinquan Intelligent Equipment Co., Ltd., the brand is EFL-AlgMA-300k, and the viscosity is 300 mPa·s, wherein the degree of substitution of the methacryl group is 40%;

[0153] EDOT;

[0154] Oxidizing agent: sodium persulfate;

[0155] First methacrylated polymer: methacrylated gelatin, the manufacturer is Suzhou Yongqinquan Intelligent Equipment Co., Ltd., the product number is EFL-GM-90, and the degree of substitution of the methacryl group is 90%;

[0156] Polylactic acid: the manufacturer is Shanghai Maikelin Biochemical Technology Co., Ltd., and the product number is P875107;

[0157] Solvent: hexafluoroisopropanol;

[0158] Photoinitiator solution A: composed of photoinitiator I2959 and anhydrous ethanol, the concentration is 10 mg / mL;

[0159] Second methacrylated polymer: methacrylated gelatin, the manufacturer is Suzhou Yongqinquan Intelligent Equipment Co., Ltd., the product number is EFL-GM-90, and the degree of substitution of the methacryl group is 90%;

[0160] Photoinitiator solution B: composed of photoinitiator I2959 and anhydrous ethanol, the concentration of the photoinitiator solution is 1 mg / mL;

[0161] (2) preparing the conductive material;

[0162] (2.1) mixing deionized water, methacrylated sodium alginate and EDOT and stirring at a speed of 8000 rpm for 10 min to obtain an emulsion; wherein the mass ratio of EDOT to methacrylated sodium alginate is 1:2, and the mass ratio of EDOT to deionized water is 1:50;

[0163] (2.2) adding an oxidizing agent to the emulsion, stirring for 48 h, and then sequentially performing dialysis, freezing and freeze-drying to remove unreacted EDOT and deionized water therein, to obtain the conductive material; wherein the mass ratio of EDOT to oxidizing agent in the emulsion is 1:2;

[0164] The finally prepared conductive material is a micellar particle with PEDOT as the core and methacrylated sodium alginate as the shell;

[0165] (3) preparing the electrospun nanofiber crosslinked membrane;

[0166] (3.1) stirring and uniformly mixing the first methacrylated polymer, polylactic acid and solvent to prepare a spinning solution with a concentration of 150 mg / mL, and preparing an electrospun nanofiber membrane by electrospinning; wherein the mass ratio of the first methacrylated polymer to polylactic acid is 10:1;

[0167] The process parameters of electrospinning include: the injection speed of the spinning solution is 2.5 mL / h, the spinning voltage is 20 kV, the receiving distance is 20 cm, the environmental temperature is 26℃, the environmental relative humidity is 70%, and the rotating drum collector rotates at a speed of 1000 rpm;

[0168] (3.2) immersing the electrospun nanofiber membrane in the photoinitiator solution A, and irradiating it with ultraviolet light source, and then sequentially performing washing and normal pressure drying, to obtain the electrospun nanofiber crosslinked membrane; wherein the mass-volume ratio of the electrospun nanofiber membrane to the photoinitiator solution A is 1 g:200 mL, the distance between the ultraviolet light source and the electrospun nanofiber membrane is 5 cm, the irradiation intensity of the ultraviolet light is 10 mW / cm 2 , the irradiation wavelength is 365 nm, and the irradiation time is 30 min;

[0169] (4) preparing the water dispersion;

[0170] The electrospinning nanofiber crosslinked membrane is cut and mixed with deionized water to homogenize, then the second methacrylated polymer and the conductive material prepared in step (2) are added and mixed and dispersed for 2h to obtain a water dispersion; wherein the homogenization speed is 8000rpm, the homogenization time is 10min, the concentration of the system after homogenization is 5mg / mL, and the mass ratio of the nanofiber, the second methacrylated polymer and the conductive material is 10:1:20;

[0171] (5) The water dispersion is frozen in liquid nitrogen and freeze-dried to obtain an intermediate product; wherein the liquid nitrogen freezing time is 30min;

[0172] (6) The intermediate product is soaked in a photoinitiator solution B, then it is irradiated with ultraviolet light, and then it is sequentially washed, frozen in liquid nitrogen and freeze-dried to obtain the conductive nanofiber aerogel for wound repair and exudate monitoring; wherein the mass-volume ratio of the intermediate product to the photoinitiator solution B is 1g:50mL, the distance between the ultraviolet light source and the intermediate product is 15cm, the irradiation intensity of the ultraviolet light is 1mW / cm 2 , the irradiation wavelength is 365nm, the irradiation time is 10min, and the liquid nitrogen freezing time is 10min.

[0173] The finally prepared conductive nanofiber aerogel for wound repair and exudate monitoring comprises a matrix and a conductive material dispersed in the matrix;

[0174] The matrix is composed of nanofibers and a second methacrylated polymer, the nanofibers contain a first methacrylated polymer, the nanofibers are staggered and overlapped to form a three-dimensional skeleton, and the overlapped parts are wrapped by the second methacrylated polymer;

[0175] The conductive material, the nanofibers and the second methacrylated polymer are crosslinked with each other to form a stable three-dimensional structure;

[0176] The porosity of the conductive nanofiber aerogel for wound repair and exudate monitoring is 99%, the density is 12mg / cm 3 , the electrical conductivity is 0.15S / m, the static contact angle is 40°, the liquid absorption rate is 4000%, the cell survival rate is 92%, and there is no conductive material dissolution.

[0177] Example 4

[0178] A preparation method of a conductive nanofiber aerogel for wound repair and exudate monitoring, the steps are as follows:

[0179] (1) Preparation of raw materials;

[0180] Deionized water;

[0181] Methacrylated sodium alginate: the manufacturer is Suzhou Yongqinquan Intelligent Equipment Co., Ltd., the brand is EFL-AlgMA-300k, and the viscosity is 300 mPa·s, wherein the degree of substitution of the methacryl group is 40%;

[0182] EDOT;

[0183] Oxidizing agent: ammonium persulfate;

[0184] First methacrylated polymer: methacrylated silk fibroin, the manufacturer is Suzhou Yongqinquan Intelligent Equipment Co., Ltd., the product number is EFL-SilMA-001, and the degree of substitution of the methacryl group is 40%;

[0185] Polylactic acid: the manufacturer is Shanghai Maikelin Biochemical Technology Co., Ltd., and the product number is P875107;

[0186] Solvent: hexafluoroisopropanol;

[0187] Photoinitiator solution A: composed of photoinitiator I2959 and anhydrous ethanol, and the concentration is 15 mg / mL;

[0188] Second methacrylated polymer: methacrylated chitosan, the manufacturer is Suzhou Yongqinquan Intelligent Equipment Co., Ltd., the brand is EFL-S-CSMA-100k, and the degree of substitution of the methacryl group is 30%;

[0189] Photoinitiator solution B: composed of photoinitiator I2959 and anhydrous ethanol, and the concentration of the photoinitiator solution is 5 mg / mL;

[0190] (2) Preparing the conductive material;

[0191] (2.1) Mixing deionized water, methacrylated sodium alginate and EDOT and stirring at a speed of 8000 rpm for 10 min to obtain an emulsion; wherein the mass ratio of EDOT to methacrylated sodium alginate is 1:2, and the mass ratio of EDOT to deionized water is 1:50;

[0192] (2.2) After adding the oxidizing agent to the emulsion, stirring for 48 h, and then sequentially performing dialysis, freezing and freeze-drying to remove the unreacted EDOT and deionized water therein, the conductive material is obtained; wherein the mass ratio of EDOT to oxidizing agent in the emulsion is 1:0.5;

[0193] The finally prepared conductive material is a micellar particle with PEDOT as the core and methacrylated sodium alginate as the shell;

[0194] (3) Preparing the electrospun nanofiber crosslinked film;

[0195] (3.1) The first methacrylated polymer, polylactic acid, and solvent are stirred and mixed to prepare a spinning solution with a concentration of 120 mg / mL, and an electrostatic nanofiber membrane is prepared by electrospinning; wherein the mass ratio of the first methacrylated polymer to the polylactic acid is 10:10;

[0196] The process parameters of electrospinning include: the injection speed of the spinning solution is 2 mL / h, the spinning voltage is 15 kV, the receiving distance is 15 cm, the environmental temperature is 25℃, the environmental relative humidity is 60%, and the rotating drum collector rotates at a speed of 200 rpm;

[0197] (3.2) The electrospun nanofiber membrane is immersed in the photoinitiator solution A, and is subjected to ultraviolet light irradiation using an ultraviolet light source, and is then sequentially washed and dried at normal pressure to obtain an electrospun nanofiber crosslinked membrane; wherein the mass-volume ratio of the electrospun nanofiber membrane to the photoinitiator solution A is 1 g:100 mL, the distance between the ultraviolet light source and the electrospun nanofiber membrane is 10 cm, the irradiation intensity of the ultraviolet light irradiation is 6 mW / cm 2 , the irradiation wavelength is 365 nm, and the irradiation time is 20 min;

[0198] (4) A water dispersion is prepared;

[0199] The electrospun nanofiber crosslinked membrane is cut and mixed with deionized water to obtain a homogeneous mixture, and then the second methacrylated polymer and the conductive material prepared in step (2) are added and mixed and dispersed for 1.5 h to obtain a water dispersion; wherein the homogenization speed is 10,000 rpm, the homogenization time is 20 min, the concentration of the system after homogenization is 10 mg / mL, and the mass ratio of the nanofiber, the second methacrylated polymer, and the conductive material is 10:10:10;

[0200] (5) The water dispersion is subjected to liquid nitrogen freezing and freeze-drying to obtain an intermediate product; wherein the liquid nitrogen freezing time is 15 min;

[0201] (6) The intermediate product is immersed in the photoinitiator solution B, and is subjected to ultraviolet light irradiation using an ultraviolet light source, and is then sequentially washed, subjected to liquid nitrogen freezing, and freeze-dried to obtain a conductive nanofiber aerogel for wound repair and exudate monitoring; wherein the mass-volume ratio of the intermediate product to the photoinitiator solution B is 1 g:100 mL, the distance between the ultraviolet light source and the intermediate product is 10 cm, the irradiation intensity of the ultraviolet light irradiation is 6 mW / cm 2 , the irradiation wavelength is 365 nm, the irradiation time is 20 min, and the liquid nitrogen freezing time is 20 min.

[0202] The conductive nanofiber aerogel for wound repair and exudate monitoring finally prepared includes a base body and a conductive material dispersed in the base body;

[0203] The base is composed of nanofibers and a second methacrylated polymer, the nanofibers containing a first methacrylated polymer, the nanofibers being staggered and lapped to form a three-dimensional skeleton, the lapped places being wrapped by the second methacrylated polymer;

[0204] The electrically conductive material, the nanofibers and the second methacrylated polymer are crosslinked with each other to form a stable three-dimensional structure;

[0205] The porosity of the electrically conductive nanofiber aerogel for wound repair and exudate monitoring is 98.5%, the density is 18 mg / cm 3 , the conductivity is 0.18 S / m, the static contact angle is 30°, the liquid absorption rate is 4100%, the cell survival rate is 90%, and there is no dissolution of the electrically conductive material.

[0206] Example 5

[0207] A preparation method of an electrically conductive nanofiber aerogel for wound repair and exudate monitoring, the steps being as follows:

[0208] (1) Preparation of raw materials;

[0209] Deionized water;

[0210] Methacrylated sodium alginate: the manufacturer is Suzhou Yongqinquan Intelligent Equipment Co., Ltd., the brand is EFL-AlgMA-300k, and the viscosity is 300 mPa·s, wherein the degree of substitution of the methacryl group is 40%;

[0211] EDOT;

[0212] Oxidant: ammonium persulfate;

[0213] First methacrylated polymer: methacrylated gelatin, the manufacturer is Suzhou Yongqinquan Intelligent Equipment Co., Ltd., the product number is EFL-GM-60, and the degree of substitution of the methacryl group is 60%;

[0214] Polylactic acid: the manufacturer is Shanghai Maikelin Biochemical Technology Co., Ltd., and the product number is P875107;

[0215] Solvent: hexafluoroisopropanol;

[0216] Photoinitiator solution A: composed of photoinitiator I2959 and anhydrous ethanol, the concentration being 15 mg / mL;

[0217] Second methacrylated polymer: methacrylated sodium alginate, the manufacturer is Suzhou Yongqinquan Intelligent Equipment Co., Ltd., the brand is EFL-AlgMA-300k, and the degree of substitution of the methacryl group is 40%;

[0218] Photoinitiator solution B: composed of photoinitiator I2959 and anhydrous ethanol, the concentration of the photoinitiator solution is 5 mg / mL;

[0219] (2) preparing the conductive material;

[0220] (2.1) mixing deionized water, methacrylated sodium alginate and EDOT and stirring at a speed of 15000 rpm for 30 min to obtain an emulsion; wherein the mass ratio of EDOT to methacrylated sodium alginate is 1:0.5, and the mass ratio of EDOT to deionized water is 1:100;

[0221] (2.2) adding an oxidizing agent to the emulsion, stirring for 24 h, and then sequentially performing dialysis, freezing and freeze-drying to remove unreacted EDOT and deionized water therein, to obtain the conductive material; wherein the mass ratio of EDOT to oxidizing agent in the emulsion is 1:2.5;

[0222] The finally prepared conductive material is a micellar particle with PEDOT as the core and methacrylated sodium alginate as the shell;

[0223] (3) preparing the electrospun nanofiber crosslinked membrane;

[0224] (3.1) stirring and uniformly mixing the first methacrylated polymer, polylactic acid and solvent to prepare a spinning solution with a concentration of 120 mg / mL, and preparing an electrospun nanofiber membrane by electrospinning; wherein the mass ratio of the first methacrylated polymer to polylactic acid is 10:10;

[0225] The process parameters of electrospinning include: the injection speed of the spinning solution is 2 mL / h, the spinning voltage is 15 kV, the receiving distance is 15 cm, the environmental temperature is 25℃, the environmental relative humidity is 60%, and the rotating drum collector rotates at a speed of 200 rpm;

[0226] (3.2) immersing the electrospun nanofiber membrane in the photoinitiator solution A, and irradiating it with ultraviolet light source, and then sequentially performing washing and normal pressure drying, to obtain the electrospun nanofiber crosslinked membrane; wherein the mass-volume ratio of the electrospun nanofiber membrane to the photoinitiator solution A is 1 g:100 mL, the distance between the ultraviolet light source and the electrospun nanofiber membrane is 10 cm, the irradiation intensity of the ultraviolet light is 6 mW / cm 2 , the irradiation wavelength is 365 nm, and the irradiation time is 20 min;

[0227] (4) preparing the water dispersion;

[0228] The electrospinning nanofiber crosslinked membrane is cut and mixed with deionized water to homogenize, then the second methacrylated polymer and the conductive material prepared in step (2) are added and mixed and dispersed for 1.5 h to obtain a water dispersion; wherein the homogenization speed is 10000 rpm, the homogenization time is 20 min, the concentration of the system after homogenization is 20 mg / mL, and the mass ratio of the nanofiber, the second methacrylated polymer and the conductive material is 10:10:10;

[0229] (5) The water dispersion is frozen in liquid nitrogen and freeze-dried to obtain an intermediate product; wherein the liquid nitrogen freezing time is 5 min;

[0230] (6) The intermediate product is soaked in a photoinitiator solution B, then subjected to ultraviolet light irradiation using an ultraviolet light source, and then sequentially subjected to washing, liquid nitrogen freezing and freeze-drying to obtain the conductive nanofiber aerogel for wound repair and exudate monitoring; wherein the mass-to-volume ratio of the intermediate product to the photoinitiator solution B is 1 g:100 mL, the distance between the ultraviolet light source and the intermediate product is 10 cm, the irradiation intensity of the ultraviolet light is 6 mW / cm 2 , the irradiation wavelength is 365 nm, the irradiation time is 20 min, and the liquid nitrogen freezing time is 20 min.

[0231] The finally prepared conductive nanofiber aerogel for wound repair and exudate monitoring comprises a matrix and a conductive material dispersed in the matrix;

[0232] The matrix is composed of nanofibers and a second methacrylated polymer, the nanofibers contain a first methacrylated polymer, the nanofibers are staggered and lapped to form a three-dimensional skeleton, and the lapped parts are wrapped by the second methacrylated polymer;

[0233] The conductive material, the nanofiber and the second methacrylated polymer are crosslinked with each other to form a stable three-dimensional structure;

[0234] The porosity of the conductive nanofiber aerogel for wound repair and exudate monitoring is 98%, the density is 20 mg / cm 3 , the electrical conductivity is 0.2 S / m, the static contact angle is 0°, the liquid absorption rate is 4500%, the cell survival rate is 90%, and there is no conductive material elution.

Claims

1. A conductive material, characterized in that, These are micelle particles with PEDOT as the core and sodium methacryloyl alginate as the shell.

2. A method for preparing a conductive material as described in claim 1, characterized in that, Deionized water, sodium methacrylamide alginate, and EDOT are mixed and stirred to obtain an emulsion. The EDOT in the emulsion is controlled to oxidize to PEDOT. Then, the unreacted EDOT and deionized water are removed to obtain the conductive material.

3. The method according to claim 2, characterized in that, The viscosity of sodium methacryloylated alginate is 300 mPa·s, and the degree of substitution of the methacryloyl group in sodium methacryloylated alginate is 40%; the mass ratio of EDOT to sodium methacryloylated alginate is 1:0.5-2; the stirring speed is 8000-15000 rpm, and the stirring time is 10-30 min.

4. The method according to claim 2, characterized in that, Controlling the oxidation of EDOT to PEDOT in the emulsion refers to adding an oxidant to the emulsion and stirring the reaction for 24-48 hours; the mass ratio of EDOT to oxidant is 1:0.5-2.

5.

5. A conductive nanofiber aerogel for wound repair and exudation monitoring, characterized in that, Includes the matrix and conductive materials dispersed in the matrix; The matrix is ​​composed of nanofibers and a second methacrylamide polymer. The nanofibers contain the first methacrylamide polymer and are interwoven to form a three-dimensional skeleton. The overlapping parts are wrapped by the second methacrylamide polymer. The conductive material, nanofibers, and dimethacrylamide polymer cross-link with each other to form a stable three-dimensional structure; The mass ratio of nanofibers, dimethacrylamide polymer, and conductive material is 10:1-20:5-20; The conductive material is the conductive material as described in claim 1.

6. The conductive nanofiber aerogel for wound repair and exudation monitoring according to claim 5, characterized in that, The first methacrylamide polymer is one or more of methacrylamide gelatin and methacrylamide silk fibroin. The degree of substitution of the methacryloyl group in the first methacryloyl polymer is 40-90%; The second methacrylamide polymer is one or more of methacrylamide gelatin, methacrylamide sodium alginate, and methacrylamide chitosan, and the degree of substitution of the methacrylamide group in the second methacrylamide polymer is 30-90%.

7. A conductive nanofiber aerogel for wound repair and exudation monitoring according to claim 5 or 6, characterized in that, Conductive nanofiber aerogels for wound repair and exudation monitoring have a porosity ≥98% and a density ≤20 mg / cm³. 3 The conductivity is 0.1-0.2 S / m, the static contact angle is ≤50°, the liquid absorption rate is ≥4000%, and the cell viability is ≥90%.

8. A method for preparing a conductive nanofiber aerogel for wound repair and exudation monitoring as described in any one of claims 5 to 7, characterized in that, First, an aqueous dispersion containing nanofibers, conductive materials, and a second methacrylamide polymer was dissolved and then subjected to liquid nitrogen freezing and freeze-drying to obtain an intermediate product. Then, a cross-linking reaction was initiated in the double bonds of the methacrylamide groups contained in the intermediate product to obtain a conductive nanofiber aerogel for wound repair and exudation monitoring.

9. The method according to claim 8, characterized in that, The preparation process of the aqueous dispersion is as follows: the electrospun nanofiber crosslinked membrane is cut into pieces and mixed with deionized water and homogenized. Then, the second methacrylamide polymer and conductive material are added to it and mixed and dispersed to obtain the aqueous dispersion. The preparation process of the electrospun nanofiber crosslinked membrane is as follows: the first methacryloyl polymer, polylactic acid and solvent are stirred and mixed to prepare the spinning solution, and the electrospun nanofiber membrane is prepared by electrospinning. The electrospun nanofiber membrane is then pre-crosslinked to obtain the electrospun nanofiber crosslinked membrane.

10. The method according to claim 8, characterized in that, The process of initiating a cross-linking reaction of the double bonds in the methacryloyl group contained in the intermediate product refers to: immersing the intermediate product in a photoinitiator solution, irradiating it with ultraviolet light using an ultraviolet light source, and then sequentially washing, freezing in liquid nitrogen, and freeze-drying it. The concentration of the photoinitiator solution is 1-10 mg / mL; The mass-to-volume ratio of the intermediate product to the photoinitiator solution was 1 g: 50-200 mL; The distance between the ultraviolet light source and the intermediate product is 5-15 cm; The intensity of ultraviolet light irradiation is 1-10 mW / cm². 2 The irradiation wavelength is 365nm and the irradiation time is 10-30min.

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