In 2016, this is very beneficial to isolate the pollution of external moisture impurities, while absorbing the liquid from the wound, keeping the wound in a relatively dry environment and preventing wound infection;
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glasses frames,eyeglass frames,frames for glasses,eyewear frames,optical frames Belieye (Jiangsu) Co.,LTD , https://www.believeglasses.com Principle and application of inorganic antibacterial fiber
The fiber mat prepared by the electrospinning method is formed by disorderly stacking of nano-sized fibers and has a porous structure, so that it has good gas permeability, is favorable for cell respiration, does not cause dry cracking of the wound, and is also a small hole. Structure, preventing bacterial invasion and wound infection. This new nanofiber mat has better ability to maintain moisture and gas exchange balance than traditional gauze and bandages;
Easy to prepare multi-component fiber materials [27]. Any solution can be electrospun under suitable conditions as long as it has a certain conductivity and a suitable viscosity. Therefore, it is possible to mix a plurality of components and to spin a multi-component, different-shaped fiber. The singularity of the composition of traditional materials and the uncontrollability of the morphology;
Versatility. Electrospinning can be used to make materials with different functions into a composite new functional material. The antibacterial material, the tissue repair material, and the like can be coated in the fiber matrix, so that the electrospun single layer or the same fiber felt has functions other than antibacterial, and can reduce the secondary wound caused by frequent dressing replacement. Trauma; it is also possible to combine the antibacterial properties with the sustained release properties of the drug to prepare a drug sustained release material having antibacterial properties;
Biological simulation. Nanofiber mats prepared by electrospinning technology were used to simulate the structure and biological function of extracellular matrix [28]. The electrospinning process causes the different layers of the spun fibers to be arranged in a two-dimensional disorder. When the fiber diameter is between 50 and 500 nm, the fiber mat can simulate the physical structure of the human extracellular matrix. The extracellular matrix is ​​a non-cellular tissue in all tissues that acts as a scaffold during wound healing to promote the formation of new cells. The extracellular matrix has a certain elasticity, and the fiber mat prepared by electrospinning has a certain mechanical strength, and can achieve the flexibility of the extracellular matrix. 3 Electrospinning antibacterial fiber classification According to the composition of antibacterial agent in antibacterial material prepared by electrospinning technology, it can be divided into inorganic antibacterial fiber, natural antibacterial fiber and composite antibacterial fiber.
Inorganic antibacterial fiber In inorganic materials, many metals or their oxides have broad-spectrum antibacterial properties. Inorganic antibacterial agents are widely used due to their long-lasting, washing-resistance, heat-resistance, acid and alkali resistance, bacteria resistance to drug resistance, and non-toxic and harmless to human health. Representative of silver nanoparticles, usually added in an amount of 6% - 8% (mass fraction) to achieve sterilization. There are three main methods for preparing inorganic nanoparticles/polymer fibers by electrospinning technology [29-31]: electrospinning after direct blending, sol-gel electrospinning and precursor in-situ formation. In situ generation method can accurately control the proportion of antibacterial agent added, and avoid the agglomeration of nanoparticles caused by direct blending and the disadvantage of sol-gel-gel ageing.
The silver acetate/PVA polymer fiber membrane was prepared by electrospinning method, and then the silver-coated fiber membrane was obtained by ultraviolet irradiation. The fiber membrane with a silver content of 5% was obtained by turbidity analysis (average particle diameter d=15.2 nm). The antibacterial property of the fiber membrane is less than that of the silver content of 1% (d = 12.8 nm), indicating that the smaller the silver particles in the fiber membrane, the easier it is to be freed from the fiber membrane, moving in the solution, and improving the sterilization efficiency. This method also proves that the in-situ method can avoid the agglomeration of nanoparticles. Wang Linfei et al [33] in the polyacrylonitrile solution, first using tea polyphenols as a reducing agent, the in-situ reduction method was used to prepare nano-silver particle precursors; then PAN spinning fibers with Ag nanoparticles were prepared by electrospinning technique. In Figures 2a and 2c, it can be observed that the Ag nanoparticles supported on the PAN nanofibers are spherical and have good dispersibility, and the average particle size is about 4.27 nm. In the microbial antibacterial experiment, the bacteriostatic bands of Escherichia coli and Staphylococcus aureus were 2.8 and 3.1 mm, respectively. According to the evaluation criteria of antimicrobial properties, Ag nanoparticles/PAN nanofibers have better antibacterial effects. DUAN et al [34] using polycaprolactone as a solvent, silver-doped zirconium phosphate AgZ (Ag0.16Na0.84Zr2(PO4)3) as a solute, electrospinning, the obtained fiber has excellent antibacterial properties, microorganisms Antibacterial tests showed that the inhibition rate against Staphylococcus aureus reached 99.27%, and that of E. coli reached 98.44%, which had a high antibacterial rate; in the skin fibroblast culture test, fibroblasts could Normal adsorption and proliferation on the fiber mat containing nano-AgZ, which proves that the nano-AgZ electrospun antibacterial fiber felt has good biocompatibility. With the development of inorganic antibacterial agents, TiO2 has received extensive attention and research. TiO2 can decompose bacteria and pollutants under photocatalytic conditions, and it is chemically stable, safe and non-toxic. It has become one of the most promising green nano-antibacterial materials with great development value. HEM et al [35] directly added P25 (80% anatase, 20% rutile ore) to nylon - 6 spinning solution, and prepared TiO2 -containing nylon - 6 nanometer antibacterial fiber by electrospinning. WU et al [36] studied the preparation of biocompatible fiber membranes with antibacterial properties by adding pre-prepared TiO2NPs to polylactic acid-glycolic acid (PLGA) electrospinning solution. The inorganic antibacterial fiber material prepared by the electrospinning technology can avoid the agglomeration of the nanoparticles by using the in-situ method, improve the dispersibility of the nanoparticles, and promote the interaction of the nanoparticles with the cells during the antibacterial action, thereby killing the bacteria. Or inhibit the effect of bacterial reproduction. However, the electrospinning technology is easy to introduce impurities, including reducing agents, surfactants that are not modified on the surface of the nanoparticles, and reaction by-product impurities, thereby affecting the antibacterial properties and even impairing the antibacterial properties.
The application of natural antibacterial fiber electrospinning in natural polymer materials has been limited by the polymer polyelectrolyte effect, so the research in this field has limitations. At present, the natural polymers that can be used in the electrospinning method to prepare fibers mainly include polysaccharide biopolymers and protein biopolymers, while the antibacterial effects are mainly polysaccharide polymer materials. In the research work of preparing natural antibacterial fiber membrane, chitosan is mainly represented. Chitosan is prepared by reprocessing of chitin. Its molecular structure is linear macromolecule, which has biocompatibility, antibacterial property and gas permeability. And biodegradable, modified chitosan also has amphiphilic properties. Based on these characteristics, chitosan has been a hotspot in the research of scholars [37-38], but the application of chitosan in electrospinning technology has been limited by the solubility of chitosan, a single chitosan for static electricity. Spinning has strict requirements on solvents. VRIEZE et al. first electrospin a single chitosan under the conditions of acetic acid [39] or trifluoroacetic acid [40-41]. The electrospun fibers obtained by this method have Antibacterial effect. Under the problem of single chitosan solubility problem, the researchers used chitosan derivative-quaternary ammonium chitosan as the electrospinning solute. The quaternary ammonium chitosan has good solubility and also has better antibacterial properties than chitosan [42]. Electrospinning is carried out using water or PVP as a solvent, and the obtained fiber felt is against Staphylococcus aureus and Escherichia coli has an antibacterial effect. A collagen/chitosan electrospun nanofiber membrane for wound dressing is prepared by electrospinning, which has no effect on the growth of fibroblasts. The fiber membrane shows no cytotoxicity. It has good in vitro biocompatibility; animal experiments show better wound healing than commercial collagen sponge dressings. Due to the inherent biological properties of natural materials, it has an irreplaceable role in the biocompatibility and degradability of antibacterial fibers. Therefore, electrospinning natural antibacterial fibers have become a research hotspot, and also occupy a certain proportion in industrial production. However, natural antibacterial agents have poor heat resistance, short potency, and are generally biomacromolecules with high relative molecular mass [45], and their solubility in electrospinning solution is a need to be solved. The problem. There are few types of highly effective antibacterial natural antibacterial agents available at present, and new and highly effective antibacterial agents are found in the development direction of the field GwKb9FzTx 
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