A melt-blown nonwoven fabric, a method for producing the same, and use thereof

Abstract

The application provides a melt-blown non-woven fabric and a preparation method and application thereof. The first aspect of the application provides a preparation method of a melt-blown non-woven fabric, wherein polypropylene resin is used as a base, nano-silver wires and an electret are added, and then melt extrusion, melt-blown spinning and electret treatment are sequentially performed to obtain an electret melt-blown non-woven fabric; and the electret melt-blown non-woven fabric is subjected to subsequent treatment to obtain a melt-blown non-woven fabric. The melt-blown non-woven fabric provided by the application has good antiviral effect, and the results of multiple complete skin irritation tests show that the skin irritation index of the non-woven fabric is 0, and the skin irritation intensity is non-irritating; in-vitro cytotoxicity test detection shows that the non-woven fabric has no cytotoxicity. Therefore, the melt-blown non-woven fabric provided by the application can be applied to the fields of clothing, medical treatment, industry and the like, and can be particularly applied to the preparation of protective products.

Description

TECHNICAL FIELD

[0001] The present application relates to a melt-blown non-woven fabric and a preparation method and application thereof, and relates to the technical field of melt-blown non-woven fabrics. BACKGROUND

[0002] With the increasing attention to life and health, the demand for antiviral products is gradually increasing, and antiviral non-woven fabrics have become high-end demand products in the industry. The existing antiviral non-woven fabrics are generally woven from antiviral raw silk. Due to the high cost of raw materials and high process requirements, the popularization degree is poor. In addition, the existing antiviral non-woven fabrics also have the problem of unsatisfactory antiviral effect. Therefore, developing a non-woven fabric with good antiviral effect is one of the technical problems to be solved in the field. SUMMARY

[0003] The present application provides a melt-blown non-woven fabric and a preparation method thereof for improving the antiviral effect of non-woven fabrics.

[0004] The present application also provides the application of the above melt-blown non-woven fabric in the preparation of protective products.

[0005] The present application provides a preparation method of a melt-blown non-woven fabric, comprising the following steps:

[0006] After adding nano-silver wires and an electret into the polypropylene resin, melt extrusion treatment is performed to obtain an electret master batch; the electret master batch is melt-blown to form a fiber structure; and the formed fiber structure is subjected to electret treatment to obtain an electret melt-blown non-woven fabric;

[0007] The electret melt-blown non-woven fabric is soaked in acetone, and after soaking for 5-9 days, the electret melt-blown non-woven fabric is taken out and placed in a fat extractor after drying for extraction treatment, and after extraction treatment, an extracted fabric sample is obtained;

[0008] The Co 60～ The extracted fabric sample is irradiated by gamma rays to obtain a radiation fabric sample;

[0009] The radiation fabric sample is placed in a protein solution for padding treatment, the protein solution includes a first protein and a second protein, the first protein has an amino acid sequence as shown in SEQ ID NO: 1, and the second protein has an amino acid sequence as shown in SEQ ID NO: 2, and the melt-blown non-woven fabric is obtained after the treatment.

[0010] In a specific embodiment, the concentration of the first protein in the protein solution is 100nM, and the concentration of the second protein is 100nM.

[0011] In an embodiment, the protein solution further comprises an active ingredient derived from Chinese medicinal materials, wherein the Chinese medicinal materials comprise one or more of rhubarb, Sophora flavescens, Phellodendri, Chinese cork tree, Semen Haloxylon, and Coptis chinensis.

[0012] In an embodiment, the active ingredient derived from Chinese medicinal materials is prepared by the following method:

[0013] The Chinese medicinal materials are crushed, and the crushed Chinese medicinal material powder is placed in a percolation cylinder. The active ingredient in the Chinese medicinal materials is extracted by percolation, and the percolation liquid is collected.

[0014] The percolation liquid is concentrated to obtain the active ingredient derived from Chinese medicinal materials.

[0015] In an embodiment, the concentration of the active ingredient derived from Chinese medicinal materials is 1 g / L.

[0016] In an embodiment, the mass ratio of the polypropylene resin, the nano-silver wire, and the electret is 7:1:1.

[0017] In an embodiment, the dose of the irradiation is 10.98 kGy.

[0018] In an embodiment, during the padding treatment, the bath ratio is 1:50, and the wet pick-up rate is 120%.

[0019] The second aspect of the present application provides a melt-blown non-woven fabric prepared by any of the above-mentioned preparation methods.

[0020] The third aspect of the present application provides the application of the above-mentioned melt-blown non-woven fabric in protective products.

[0021] The melt-blown non-woven fabric provided by the present application has good antiviral effect, and the results of multiple complete skin irritation tests show that the skin irritation index of the non-woven fabric is 0, and the skin irritation intensity is non-irritating. In vitro cytotoxicity test shows that the non-woven fabric has no cytotoxicity. Therefore, the melt-blown non-woven fabric provided by the present application can be applied in the fields of clothing, medical treatment, and industry, and can be particularly applied in the preparation of protective products. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 The structure diagram of the first protein provided by an embodiment of the present application is shown;

[0023] Figure 2 The structure diagram of the second protein provided by an embodiment of the present application is shown;

[0024] Figure 3 The SDS-PAGE diagram of the first protein and the second protein provided by an embodiment of the present application is shown. DETAILED DESCRIPTION

[0025] In order to make the objects, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative effort belong to the scope of protection of the present application.

[0026] The present application provides a preparation method of melt-blown non-woven fabric, comprising the following steps:

[0027] After adding nano-silver wire and electret into polypropylene resin, melt extrusion treatment is carried out to obtain electret master batch; melt-blown spinning is carried out on the electret master batch to form fiber structure; and electret treatment is carried out on the formed fiber structure to obtain electret melt-blown non-woven fabric;

[0028] The electret melt-blown non-woven fabric is soaked in acetone, and after soaking for 5-9 days, the electret melt-blown non-woven fabric is taken out, dried and placed in a fat extractor for extraction treatment, and after extraction treatment, an extracted fabric sample is obtained;

[0029] The extracted fabric sample is irradiated by Co 60 ~γ rays to obtain a radiation fabric sample;

[0030] The radiation fabric sample is placed in a protein solution for padding treatment, the protein solution includes a first protein and a second protein, the first protein has an amino acid sequence as shown in SEQ ID NO: 1, and the second protein has an amino acid sequence as shown in SEQ ID NO: 2, and after the treatment, the melt-blown non-woven fabric is obtained.

[0031] The melt-blown non-woven fabric prepared by the above preparation method has good antiviral effect, and the results of multiple complete skin irritation tests show that the skin irritation index of the non-woven fabric is 0, and the skin irritation intensity is non-irritating; the in vitro cytotoxicity test shows that the non-woven fabric has no cytotoxicity. Therefore, the melt-blown non-woven fabric provided by the present application can be applied in the fields of clothing, medical treatment, industry, etc., and can be particularly applied in the preparation of protective products.

[0032] In a specific embodiment, the preparation method of melt-blown non-woven fabric is described in detail:

[0033] Step 1, an electret melt-blown non-woven fabric is prepared.

[0034] Firstly, the embodiment adds nano silver wire in the preparation process of the electret melt-blown non-woven fabric. The diameter of the nano silver wire is generally less than 100 nm, and the length can reach tens of microns to hundreds of microns. The nano silver wire combines the characteristics of nano materials and elemental silver, has little toxicity to cells, and has high surface activity, surface energy and catalytic performance, which can effectively improve the antibacterial and antiviral performance of the melt-blown non-woven fabric.

[0035] In the specific preparation process, the polypropylene resin, the nano silver wire and the electret agent are added into a high-speed mixer in a mass ratio of 7:1:1, mixed for 1-3 minutes at a speed of 1000-2000 revolutions per minute, to obtain a premix; the premix is input into a twin-screw extruder for melt extrusion treatment, and the temperature of each zone of the screw is 190-230°C, to obtain an electret master batch.

[0036] Further, the electret agent is a mixture of sodium stearate and 4-nitro-N-phenyl phthalimide, and the mass ratio of sodium stearate to 4-nitro-N-phenyl phthalimide is 1:1.

[0037] The electret master batch is input into a melt-blown machine for melt-blown spinning to form a fiber structure, and the formed fiber structure is treated by corona discharge to obtain an electret melt-blown non-woven fabric. The melt-blown spinning and corona discharge can use conventional technical means in the art.

[0038] Step 2, the electret melt-blown non-woven fabric is soaked in acetone, and after soaking for 5-9 days, the electret melt-blown non-woven fabric is taken out, dried and placed in a fat extractor for extraction treatment. After extraction treatment, an extracted fabric sample is obtained.

[0039] The electret melt-blown non-woven fabric obtained in step 1 is soaked in acetone, and after soaking for 5-9 days, the electret melt-blown non-woven fabric is taken out, dried and extracted in a fat extractor with ethanol to extract lipids in the electret melt-blown non-woven fabric. The extraction time can be 60-84 hours. After the extraction is completed, the extracted fabric sample is taken out and dried at 50-60°C to a constant weight.

[0040] Step 3, the extracted fabric sample is irradiated with Co 60 ~γ rays to obtain a radiation fabric sample.

[0041] The extracted fabric sample is irradiated with Co 60 ~γ rays to kill microorganisms in the extracted fabric sample and play a role in disinfection and sterilization. Further, the irradiation dose is 10.98 kGy.

[0042] Step 4, the radiation fabric sample is placed in a protein solution for padding treatment, and the melt-blown non-woven fabric is obtained after the treatment is completed.

[0043] The protein solution comprises a first protein and a second protein, which are respectively designed based on the Omicron antibody JMB2002 and the influenza virus antibody CR9114 as a natural protein backbone, using a ProteinMPNN protein sequence design method based on deep learning to generate antibody variable region sequences that more stably encode their structures, and a single-chain antibody protein is obtained by connecting a heavy chain variable region and a light chain variable region through a connecting peptide.

[0044] Further, in the protein solution, the concentration of the first protein is 100 nM, and the concentration of the second protein is 100 nM.

[0045] Further, the protein solution further comprises an active ingredient derived from a Chinese herbal medicine, and the Chinese herbal medicine comprises one or more of rhubarb, sophora, golden cypress, Chinese gall, coptis.

[0046] Further, the active ingredient derived from the Chinese herbal medicine is prepared by the following preparation method: the Chinese herbal medicine is crushed, and the crushed Chinese herbal medicine powder is placed in a percolation cylinder, and the active ingredient in the Chinese herbal medicine is extracted by percolation method, and the percolate is collected.

[0047] The percolate is concentrated to obtain the active ingredient derived from the Chinese herbal medicine.

[0048] Specifically, during the percolation process, 75% ethanol can be used for percolation treatment of the Chinese herbal medicine powder.

[0049] Specifically, in the protein solution, the concentration of the active ingredient derived from the Chinese herbal medicine is 1 g / L.

[0050] During the padding treatment process, the irradiated cloth sample is immersed in the protein solution for 30 min, the bath ratio is controlled to be 1:50, double immersion and double padding are performed, and the liquid retention rate is 120%, to obtain the cloth sample after padding treatment.

[0051] Finally, the cloth sample after padding treatment is dried, treated with 75% ethanol solution for 30 min, and then dried to constant weight, and placed in a desiccator for 24 h to obtain the melt-blown non-woven fabric.

[0052] The melt-blown non-woven fabric prepared by the above preparation method has good antiviral effect, and the results of multiple complete skin irritation tests show that the skin irritation index of the non-woven fabric is 0, and the skin irritation intensity is non-irritating; the in vitro cytotoxicity test shows that the non-woven fabric has no cytotoxicity. Therefore, the melt-blown non-woven fabric provided by the application can be applied in the fields of clothing, medical treatment, industry, etc., and can be particularly applied in the preparation of protective products.

[0053] The second aspect of the application provides a melt-blown non-woven fabric prepared by any of the above preparation methods.

[0054] Based on the preparation method provided in the first aspect of the present application, the melt-blown non-woven fabric prepared according to the above preparation method has good antiviral effect, and has a skin irritation index of 0, a skin irritation intensity of no irritation, and no cytotoxicity, and can be applied in the fields of clothing, medical treatment, industry, etc., and especially in the preparation of protective products.

[0055] The third aspect of the present application provides the application of the above melt-blown non-woven fabric in protective products.

[0056] Based on the melt-blown non-woven fabric provided in the second aspect of the present application, the protective product prepared therefrom also has antiviral effect, and has no skin irritation and no cytotoxicity.

[0057] The following will be described in detail in combination with specific embodiments:

[0058] Embodiment 1:

[0059] The present embodiment provides a preparation method of a melt-blown non-woven fabric, which specifically comprises the following steps:

[0060] 1. Protein MPNN protein sequence design

[0061] The PDB file of the Omicron antibody JMB2002 with PDB number 7WRV and the PDB file of the influenza virus antibody CR9114 with PDB number 4FQH were downloaded from the PDB protein database (https: / / www.rcsb.org / ), and the two files were respectively imported into the ProteinMPNN module for calculation to obtain the calculated sequences, from which one sequence with a higher score was selected respectively, and the heavy chain variable region and the light chain variable region were cut off, and a designed single-chain antibody scFv was obtained by connecting a connecting peptide (GGGGSGGGGSGGGGS), and was respectively named as a first protein (JMB2002-MPNN-scFv) and a second protein (CR9114-MPNN-scFv), and the protein structure schematic diagram is as shown in Figures 1-2 The amino acid sequences are as shown in SEQ ID NO: 1-2.

[0062] The heavy chain variable region amino acid sequence in JMB2002-MPNN-scFv is:

[0063] SYSLVQSGDVTLAPGGSVSLYCTYQGGSFNNVAFQWVRQPPGGPPEFIGFIIPIENVTRVSPKYEGRVTL SADPSTKRFYFTISNLQPEDTATYYCGISNAYSSGGNDSISVWGQGVQLTVA.

[0064] The amino acid sequence of the light chain variable region in JMB2002-MPNN-scFv is:

[0065] VPTVTQTPASLTAGEGEPVTLNCTSSTPSNRKISWYKQPPGQPPQLIIDSESTLVPGVSPRYSSSGSGKNF TLSISSLLPEDVATYYCRQYDETPLVFGSGTKLTL.

[0066] The amino acid sequence of JMB2002-MPNN-scFv is:

[0067] SYSLVQSGDVTLAPGGSVSLYCTYQGGSFNNVAFQWVRQPPGGPPEFIGFIIPIENVTRVSPKYEGRVTLSADPSTKRFYFTISNLQPEDTATYYCGISNAYSSGGNDSISVWGQGVQLTVAGGGGSGGGGSGGGGSVPTVTQTPASLTAGEGEPVTLNCTSSTPSNRKISWYKQPPGQPPQLIIDSESTLVPGVSPRYSSSGSGKNFTLSISSLLPEDVATYYCRQYDETPLVFGSGTKLTL.

[0068] The nucleotide sequence of the gene encoding JMB2002-MPNN-scFv is:

[0069] Agctatagcctggtgcagagcggcgatgtgaccctggcgccgggcggcagcgtgagcctgtattgcacctatcagggcggcagctttaacaacgtggcgtttcagtgggtgcgccagccgccgggcggcccgccggaatttattggctttattattccgattgaaaacgtgacccgcgtgagcccgaaatatgaaggccgcgtgaccctgagcgcggatccgagcaccaaacgcttttattttaccattagcaacctgcagccggaagataccgcgacctattattgcggcattagcaacgcgtatagcagcggcggcaacgatagcattagcgtgtggggccagggcgtgcagctgaccgtggcgggcggcggcggcagcggcggcggcggcagcggcggcggcggcagcgtgccgaccgtgacccagaccccggcgagcctgaccgcgggcgaaggcgaaccggtgaccctgaactgcaccagcagcaccccgagcaaccgcaaaattagctggtataaacagccgccgggccagccgccgcagctgattattgatagcgaaagcaccctggtgccgggcgtgagcccgcgctatagcagcagcggcagcggcaaaaactttaccctgagcattagcagcctgctgccggaagatgtggcgacctattattgccgccagtatgatgaaaccccgctggtgtttggcagcggcaccaaactgaccctg.

[0070] The heavy chain variable region amino acid sequence of the CR9114-MPNN-scFv is:

[0071] TLQQSGDLYVAPGGSVTITCTSLNGDASKYNISWVRQPPGGPLVWVGSISPVNGVTTYAAEYEGRVTLSYDSTSNTASLTLSDLTPEDTAVYYCGLHLSSNQSSGIVVWGQGTRVVVS.

[0072] The light chain variable region amino acid sequence of the CR9114-MPNN-scFv is:

[0073] LQQPPLVSGRPGETVSISCTGNSNTIGSNPVNWYKQKPGKPPELVVYNNDQRPSWVSSRFSGSQSGTSSTLTISNLRPEDEATYYCSSWDNALNQRVFGNGTHLVV.

[0074] The amino acid sequence of the CR9114-MPNN-scFv is:

[0075] TLQQSGDLYVAPGGSVTITCTSLNGDASKYNISWVRQPPGGPLVWVGSISPVNGVTTYAAEYEGRVTLSYDSTSNTASLTLSDLTPEDTAVYYCGLHLSSNQSSGIVVWGQGTRVVVSGGGGSGGGGSGGGGSGGGGSGGGGSGGGGSGGGGSLQQPPLVSGRPGETVSISCTGNSNTIGSNPVNWYKQKPGKPPELVVYNNDQRPSWVSSRFSGSQSGTSSTLTISNLRPEDEATYYCSSWDNALNQRVFGNGTHLVV.

[0076] The nucleotide sequence of the gene encoding the CR9114-MPNN-scFv is:

[0077] accctgcagcagagcggcgatctgtatgtggcgccgggcggcagcgtgaccattacctgcaccagcctgaacggcgatgcgagcaaatataacattagctgggtgcgccagccgccgggcggcccgctggtgtgggtgggcagcattagcccggtgaacggcgtgaccacctatgcggcggaatatgaaggccgcgtgaccctgagctatgatagcaccagcaacaccgcgagcctgaccctgagcgatctgaccccggaagataccgcggtgtattattgcggcctgcatctgagcagcaaccagagcagcggcattgtggtgtggggccagggcacccgcgtggtggtgagcggcggcggcggcagcggcggcggcggcagcggcggcggcggcagcctgcagcagccgccgctggtgagcggccgcccgggcgaaaccgtgagcattagctgcaccggcaacagcaacaccattggcagcaacccggtgaactggtataaacagaaaccgggcaaaccgccggaactggtggtgtataacaacgatcagcgcccgagctgggtgagcagccgctttagcggcagccagagcggcaccagcagcaccctgaccattagcaacctgcgcccggaagatgaagcgacctattattgcagcagctgggataacgcgctgaaccagcgcgtgtttggcaacggcacccatctggtggtg.

[0078] 2. JMB 2002 - MPNN-scFv and CR9114 - MPNN-scFv protein expression, purification and characterization

[0079] 2.1, scFv protein expression: The above-mentioned JMB2002-MPNN-scFv and CR9114-MPNN-scFv gene fragments were cloned into the prokaryotic expression plasmid pET28a (kanamycin resistance, carrying a 6xHis-tag) through enzyme cutting sites Ncol (containing the start codon ATG) and Xhol, and transformed into Rosetta E. coli to obtain recombinant strains. The recombinant strains were plated on LB solid culture medium with kanamycin resistance and incubated at 37°C overnight. Single colonies were picked and inoculated into 10 ml of LB liquid medium containing kanamycin (100 mg / L), and incubated at 220 rpm and 37°C overnight. The next day, 1:100 was transferred to 1000 ml of LB liquid medium containing kanamycin, and incubated until the OD600nm was between 0.6 and 1.0. IPTG was added to different bacterial solutions at a final concentration of 0.5 mmol / L, and the induction temperature was 37°C, with 220 rpm shaking for 3 hours.

[0080] 2.2, purification of scFv protein: The bacterial solution obtained above was centrifuged to collect the bacterial pellet, which was resuspended in Ni-NTA Binding Buffer (pH = 9.0). The resuspended bacterial solution was fully lysed at 4°C for 1.5 hours under ultrasonic conditions at 50% power. The lysed bacterial solution was dissolved in 15 mL of 8 mol / L urea and filtered through a 0.22 μL filter for later use. After filtering the denatured inclusion body protein, the nickel column was placed in a low-temperature shaker at 4°C for 45 minutes to maximize the binding of the nickel column to the expressed protein with a 6xHis-tag. The nickel column was removed and reloaded, and the column was washed with Binding Buffer at a volume of 30 mL. The column was washed several times with washing buffer until the flow-through A280nm was less than 0.01. The optimal elution concentration was screened by using a gradient elution buffer method, i.e., adjusting the concentration of imidazole in the buffer from 100 mmol / L to 200 mmol / L, and then to 500 mmol / L. The breakthrough liquid was collected in a clean centrifuge tube. The optimal elution imidazole concentration was analyzed by SDS-PAGE. All steps in the protein purification process were carried out at 4°C. The scFv protein was then renatured and concentrated: the renaturation buffer was 20 mmol / L phosphate buffer with different concentrations of urea (6 mol / L, 4 mol / L, 2 mol / L, 0 mol / L) at pH = 9.0. After gradient dialysis of the protein with different concentrations of urea, the resulting target protein scFv was dialyzed into phosphate buffer. The target protein was concentrated in an ultrafiltration centrifuge tube at a centrifugal speed of about 3000 rpm. The protein was concentrated to an appropriate volume. The purified scFv was determined for protein concentration using Nanojob, and then stored at -20°C.

[0081] 2.3, scFv protein identification: 10 ug of each of the purified JMB2002-MPNN-scFv and CR9114-MPNN-scFv proteins obtained above were subjected to SDS-PAGE gel electrophoresis, and the results are shown in FIG. 2.3. The JMB2002-MPNN-scFv and CR9114-MPNN-scFv protein bands were single, and the molecular weights were both about 25 kDa. Figure 3

[0082] 3, Extraction of active ingredients from traditional Chinese medicinal materials

[0083] Rhubarb, Sophora flavescens, Phellodendri Cortex, Chinese waxleaf tree bark, Semen Haloxylon, and Coptis chinensis were mixed in a mass ratio of 1:1:1:1:1:1 to obtain mixed traditional Chinese medicinal materials. The mixed traditional Chinese medicinal materials were crushed into coarse powder, 75 g of which was soaked in 150 ml of 75% ethanol for 24 h, 200 ml of 75% ethanol was added for percolation, and the percolate was collected. The percolate was concentrated to 75 ml under a vacuum degree of -0.1 to -0.08 MPa and a temperature of 60°C on a rotary evaporator. Finally, an active ingredient extract of traditional Chinese medicinal materials with a concentration of 1 g / ml was obtained and stored in a refrigerator at 4°C for later use.

[0084] 4, Preparation of a protein solution

[0085] The active ingredient extract of traditional Chinese medicinal materials obtained by the above steps was dissolved in two purified scFv proteins, wherein the concentration of the active ingredient of traditional Chinese medicinal materials was 1 g / ml, and the concentrations of the JMB2002-MPNN-scFv and CR9114-MPNN-scFv proteins were both 100 nM.

[0086] 5, Preparation of melt-blown non-woven fabric

[0087] Sodium stearate and 4-nitro-N-phenyl phthalimide were mixed in a mass ratio of 1:1 to obtain an electret agent. Polypropylene resin, nano-silver wire, and the electret agent were mixed in a mass ratio of 7:1:1 and added to a high-speed mixer for mixing for 1-3 minutes at a speed of 1000-2000 revolutions per minute to obtain a premix. The premix was melt-extruded by a twin-screw extruder, the temperature of each zone of the screw was 190-230°C, and vacuum granulation was performed, thereby obtaining an electret master batch. Then, melt-blown spinning was performed on a melt-blown machine, and corona discharge was used for electretization, thereby obtaining an electret melt-blown non-woven fabric.

[0088] The electret melt-blown non-woven fabric was cut into a 20 cm*20 cm fabric sample (blank fabric sample). Part of the blank fabric sample was soaked in acetone for one week, dried, and then extracted in a fat extractor with ethanol for 72 h. The extracted fabric sample was dried at 50-60°C to a constant weight, thereby obtaining a purified fabric sample. The purified fabric sample was irradiated with Co 60 -γ rays at a dose of 10.98 kGy, thereby obtaining a radiation fabric sample. ​

[0089] The cloth sample was immersed in the above protein solution for 30 min, bath ratio 1:50, double immersion and double rolling, pick-up rate 120%. After drying the immersed and rolled cloth sample, it was treated with 75% ethanol solution for 30 min, then dried to constant weight, and placed in a desiccator for 24 h to balance. The melt-blown non-woven fabric was obtained.

[0090] (I) The melt-blown non-woven fabric prepared in Example 1 was sent to the Kunming Institute of Zoology, Chinese Academy of Sciences for antibacterial and antiviral detection. The detection method of Escherichia coli and Staphylococcus aureus was according to the oscillation method mentioned in GB / T 20944.3-2008 Part 3, and the detection results are shown in Table 1. The detection method of influenza virus H1N1 was according to ISO 18184:2019, and the detection results are shown in Table 2.

[0091] Table 1

[0092]

[0093]

[0094] Table 2

[0095]

[0096] According to Tables 1-2, the melt-blown non-woven fabric prepared in Example 1 has a high bacteriostatic rate on Escherichia coli and Staphylococcus aureus, and also has a high antiviral activity on influenza virus H1N1.

[0097] (II) The melt-blown non-woven fabric prepared in Example 1 was sent to the Kunming Institute of Zoology, Chinese Academy of Sciences for evaluation of the effect of killing novel coronavirus (SARS-CoV-2).

[0098] 1. Experimental materials:

[0099] Experimental group: non-woven fabric; cells: Vero-E6 cells, preserved in the biosafety level 3 laboratory of the Kunming Institute of Zoology, Chinese Academy of Sciences; virus: novel coronavirus (SARS-CoV-2), preserved in the biosafety level 3 laboratory of the Kunming Institute of Zoology, Chinese Academy of Sciences; DMEM high-sugar culture medium containing 10% or 3% inactivated fetal bovine serum (FBS), 100-200 IU / mL penicillin, and 100-200 μg / mL streptomycin.

[0100] Vero-E6 cells: Vero-E6 cells were cultured in DMEM high glucose complete medium containing 10% fetal bovine serum, and the cells were subcultured once a day before the experiment to make the cells in the logarithmic growth phase. The cells after adding virus and samples were maintained in culture with DMEM high glucose complete medium containing 3% fetal bovine serum. New coronavirus (SARS-CoV-2): Omicron BA.5.

[0101] 2. Experimental steps

[0102] (1) Sterile 96-well culture plates, 2 x 10 4 cells / 100 μL Vero-E6 cells per well, 37°C, 5% CO2 culture for 24 hours;

[0103] (2) Cut the test material to an area of 20 mm x 20 mm, ultraviolet sterilize for 30 min, then cut into 10 mm x 10 mm pieces and place in 6 50 mL sterile centrifuge tubes;

[0104] (3) Add 1 x 10 5 TCID 50 / mL virus solution to the 6 tubes containing the test sample, incubate at room temperature for 30 min and 1 h respectively, set 3 replicates for each time point; at the same time, set a virus solution blank control (without test sample);

[0105] (4) After the specified time, shake and elute the virus particles adsorbed on the test sample;

[0106] (5) Dilute the eluate 10-fold with DMEM medium (containing 2% double antibody and 3% FBS), with 7 dilution levels: original, 10 -1 , 10 -2 … 10 -6 ;

[0107] (6) Discard the cell culture fluid in the 96-well culture plates, add the diluted virus eluate to each well, 100 μL per well, 10 replicates for each dilution;

[0108] (7) Set up cell controls and virus controls at the same time;

[0109] Cell control (NC): add 100 μL DMEM medium (containing 2% double antibody and 3% FBS) per well, 10 replicates, and set up cell controls on each plate. Virus control: 10-fold gradient dilution of virus solution, same dilution gradient as test sample treatment group, 10 replicates for each dilution.

[0110] (8) Incubate in a 37°C, 5% CO2 incubator for 4-6 days;

[0111] (9) Observation of cytopathic effect (CPE) under light microscope. The cells with CPE change were recorded as "+", and the cells without CPE change or normal morphology were recorded as "-".

[0112] 3. Result calculation (antiviral effect)

[0113] (1) Calculation of antiviral activity value Mv: Mv = lg(Va / Vb) = lg(Va) - lg(Vb)

[0114] Va: virus titer of virus control

[0115] Vb: average virus titer of virus eluted from the test sample treated pathological fluid after a certain period of time

[0116] (2) Calculation of killing rate: killing rate = (Va-Vb) / Va*100%

[0117] 4. Experimental results

[0118] 4.1. CPE statistical results of each sample

[0119] (1) Sample number: experimental group 0.5h-1

[0120] Table 3

[0121]

[0122] (2) Sample number: experimental group 0.5h-2

[0123] Table 4

[0124]

[0125] (3) Sample number: experimental group 0.5h-3

[0126] Table 5

[0127]

[0128] (4) Sample number: 0.5h-virus control

[0129] Table 6

[0130]

[0131] (5) Sample number: experimental group 1h-1

[0132] Table 7

[0133]

[0134] (6) Sample number: experimental group 1h-2

[0135] Table 8

[0136]

[0137] (7) Sample No.: Experimental group 1h-3

[0138] Table 9

[0139]

[0140] (8) Sample No.: 1h-virus control

[0141] Table 10

[0142]

[0143] 5、The calculation results of virus titers in each sample are shown in Table 11, and the calculation method is according to Reed & Muench.

[0144] Table 11

[0145]

[0146] In Table 11, the calculation of the antiviral activity value Mv is Mv = lg(Va / Vb) = lg(Va)-lg(Vb), and the killing rate = (Va-Vb) / Va*100%; Va: virus titer of virus control; Vb: average virus titer of virus eluted after treating pathological fluid with test sample for a certain time.

[0147] According to Table 11, the melt-blown non-woven fabric provided in Example 1 has a significant killing effect on the novel coronavirus (SARS-CoV-2), with a killing rate of 32.3% after 0.5h and a killing rate of 79.4% after 1h.

[0148] (Three) The prepared sample was sent to the Guangdong Provincial Microorganism Analysis and Detection Center for skin irritation experiment and in vitro cytotoxicity experiment. The skin irritation experiment was carried out according to the second part (2.3.3) of the Disinfection Technical Specification (Ministry of Health 2002 edition), and the in vitro cytotoxicity experiment was carried out according to GB / T 14233.2-2005 (8).

[0149] 3.1, the method of skin irritation experiment includes:

[0150] (1) 24h before the test, the hair on both sides of the New Zealand rabbit's back spine was shaved. The shaving range was about 3cm x 3cm on the left and right sides.

[0151] (2) The next day, the test article was cut into a size of 2.5 cm x 2.5 cm in a transverse manner, and then applied to one side of the skin after being wetted with normal saline. Then, a layer of non-irritating plastic film was covered, and then fixed with non-irritating adhesive tape. The other side was shaved and used as a blank control (the treatment method of the control area was the same as that of the test area, and an equal amount of sterilized normal saline was used). The application time was 4 hours, and after the test was completed, the residual test article was removed with warm water.

[0152] (3) The application was performed once a day for 14 consecutive days. The results were observed and scored 24 hours after each application, and the scoring results are shown in Table 12.

[0153] Table 12

[0154]

[0155] According to Table 12, the melt-blown non-woven fabric provided in Example 1 has a skin irritation index of 0 for New Zealand rabbits, and the skin irritation intensity is non-irritating.

[0156] 3.2, In vitro cytotoxicity experiment

[0157] Cell type: Mouse fibroblast L929, ATCC CCL1 (NCTC clone 929), culture environment: 37.0°C carbon dioxide incubator, 5% CO2. Blank control group: complete culture medium containing 89% RPMI 1640, 10% fetal bovine serum, 1% antibiotic (100 IU / mL penicillin, 100 μg / mL streptomycin). Positive control (5% DMSO): weigh 0.05 mL of DMSO and mix 0.95 mL of complete culture medium for testing. Negative control (high-density polyethylene): weigh 2 g and add 10 mL of complete culture medium and place in a 37.0°C incubator for 24 hours. After sterilization by 0.22 μm filtration, it is used for testing. 5 g / L MTT solution: 0.1 g of MTT powder is dissolved in 20 mL of PBS, and after sterilization by 0.22 μm filtration, it is stored in a -20°C refrigerator.

[0158] Test article preparation: extraction ratio: 0.1 g / mL, take 1.5014 g of sample and add 15 mL of complete culture medium, and extract in a 37.0°C constant temperature incubator for 24 hours. The concentration of the extract is 100%, and it is used as the test article after being diluted with complete culture medium at concentrations of 75%, 50%, and 25%.

[0159] Test method:

[0160] 3.2.1, Cell suspension preparation: the cells that have been cultured for 48-72 hours and are in vigorous growth are digested with a digestion solution, then cell culture solution is added, and the mixture is mixed by pipetting and then counted under a microscope using a hemocytometer.

[0161] 3.2.2, Calculate the relative growth rate (RGR) using the tetrazolium salt (MTT) colorimetric method. Determine the cytotoxicity response according to the RGR grading criteria. The response of the negative control group should be no more than grade 1, and the positive control group should have at least a grade 3 response. If the responses of the negative control group and the positive control group are not as expected, the test should be repeated. The cytotoxicity response grading is shown in Tables 13-14.

[0162] Table 13 Cytotoxicity Response Grading (Tetrazolium Salt (MTT) Colorimetric Method)

[0163] Grade Relative growth rate, % 0 ≥100 1 80～99 2 50～79 3 30～49 4 0～29

[0164] Table 14 Cytotoxicity Response Grading (Microscopic Observation Method)

[0165] Grade Extent of reaction Reaction observed 0 None Normal cell morphology, well attached, with discrete granules in cytoplasm; no cell lysis 1 Very slight Up to 20% of cells rounded, loosely attached, no cytoplasmic granules; occasional cell lysis 2 Slight Up to 50% of cells rounded and contracted, no cytoplasmic granules; obvious cell lysis and intercellular space 3 Moderate Up to 70% of cells rounded or lysed 4 Severe Almost complete destruction of cell layer

[0166] 3.2.2, Result determination: In the case of expected responses of the negative control and the positive control, analyze and determine the degree of cytotoxicity response of the test product, and the evaluation results are shown in Tables 15-17.

[0167] Table 15 Post-intervention Cell Morphology Observation Record

[0168]

[0169]

[0170] Table 16 Post-intervention Cell Survival Rate Measured at 570 nm

[0171]

[0172] Table 17 Post-intervention Cell Survival Rate Measured at 630 nm

[0173]

[0174] According to Tables 15-17, the cell survival rate of the 100% concentration group measured at 570 nm is 84.13%, and the cytotoxicity response is less than or equal to grade 2. The cell survival rate of the 100% concentration group measured at 630 nm is 83.15%, and the cytotoxicity response is less than or equal to grade 2. It is shown that the melt-blown non-woven fabric provided in Example 1 has no cytotoxicity.

[0175] According to the above detection results, the killing rate of the melt-blown non-woven fabric prepared in the embodiment to Omicron is 79.4%, the antiviral activity rate to the influenza virus H1N1 can reach 85.38%, and the bacteriostatic rates to Escherichia coli and Staphylococcus aureus are both 99%. Moreover, the skin irritation index of the melt-blown non-woven fabric prepared is 0, the skin irritation intensity is non-irritating, and the in-vitro cytotoxicity test result is non-cytotoxic. Therefore, the melt-blown non-woven fabric provided by the application can be applied in the fields of clothing, medical treatment, industry, etc., and can be especially applied in the preparation of protective products.

[0176] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement to part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for preparing meltblown nonwoven fabric, characterized in that, Includes the following steps: Nano-silver wires and electret agents are added to polypropylene resin and then melt-extruded to obtain electret masterbatch; the electret masterbatch is melt-blown spun to form a fiber structure; and the formed fiber structure is electret-treated to obtain electret meltblown nonwoven fabric. The electret meltblown nonwoven fabric was soaked in acetone for 5 to 9 days. After soaking, the electret meltblown nonwoven fabric was taken out, dried, and placed in a fat extractor for extraction. After extraction, an extracted fabric sample was obtained. Co 60~ The extracted fabric sample was irradiated with gamma rays to obtain a radiated fabric sample. The radiation fabric sample is immersed in a protein solution for padding treatment. The protein solution includes a first protein and a second protein. The first protein has an amino acid sequence as shown in SEQ ID NO:1, and the second protein has an amino acid sequence as shown in SEQ ID NO:

2. After the treatment, the meltblown nonwoven fabric is obtained.

2. The preparation method according to claim 1, characterized in that, In the protein solution, the concentration of the first protein is 100 nM, and the concentration of the second protein is 100 nM.

3. The preparation method according to claim 1, characterized in that, The protein solution also includes active ingredients derived from traditional Chinese medicinal materials, including one or more of rhubarb, sophora flavescens, phellodendron bark, nepeta bark, kochia fruit, and coptis.

4. The preparation method according to claim 3, characterized in that, The active ingredients derived from traditional Chinese medicinal materials are prepared using the following method: The Chinese medicinal materials are pulverized, and the pulverized Chinese medicinal material powder is placed in a percolation cylinder. The active ingredients in the Chinese medicinal materials are extracted by percolation, and the percolate is collected. The percolate was concentrated to obtain the active ingredients derived from the traditional Chinese medicine.

5. The preparation method according to claim 4, characterized in that, The concentration of the active ingredient derived from the Chinese medicinal materials is 1 g / L.

6. The preparation method according to any one of claims 1 to 5, characterized in that, The mass ratio of the polypropylene resin, silver nanowires, and electret agent is 7:1:

1.

7. The preparation method according to any one of claims 1 to 5, characterized in that, The irradiation dose was 10.98 kGy.

8. The preparation method according to any one of claims 1 to 5, characterized in that, During the padding process, the liquor ratio is 1:50 and the liquid carryover rate is 120%.

9. A meltblown nonwoven fabric, characterized in that, It is prepared by the preparation method according to any one of claims 1 to 8.

10. The application of the meltblown nonwoven fabric according to claim 9 in protective products.

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