Antibacterial real silk fabric and preparation method thereof

Abstract

The present application relates to an antibacterial silk fabric and a preparation method thereof, and belongs to the technical field of functional fabrics. The preparation method comprises the following steps: S1, dispersing a zeolitic imidazolate framework material in a Dioscorea panthaica Palibin extract solution, stirring, centrifuging and drying to obtain a zeolitic imidazolate framework / Dioscorea panthaica Palibin extract; S2, impregnating silk fabric in a finishing liquid of the zeolitic imidazolate framework / Dioscorea panthaica Palibin extract to obtain the antibacterial silk fabric. The condensed tannin compound is encapsulated in the zeolitic imidazolate framework material, and the condensed tannin compound is released from the zeolitic imidazolate framework material under weak acidic conditions to react with the silk fabric. The condensed tannin compound can be combined with the protein in the cells of bacteria through hydrogen bonds, hydrophobic interaction and covalent bonds or by destroying the cell membrane of bacteria, thereby effectively inhibiting the growth of bacteria. Furthermore, the zinc ions released from the SL@ZIF-8 have antibacterial effects, which synergistically enhance the antibacterial performance of the silk fabric.

Description

Technical Field

[0001] This invention belongs to the field of functional fabric technology, and in particular relates to an antibacterial silk fabric and its preparation method. Background Technology

[0002] Silk fibers are widely loved for their comfort and are often used to make summer underwear, bedding, and health care clothing. However, when worn as underwear, they come into direct contact with the skin, making them prone to bacterial growth and potentially affecting human health. Therefore, antibacterial finishing of silk textiles is of great importance. Most antibacterial finishing methods for silk fibers involve post-treatment, using antibacterial agents to treat the silk fibers.

[0003] Chinese invention patent CN 115233445 A discloses a method for visible light catalytic antibacterial and durable finishing of silk. This method uses an antibacterial finishing agent with a phenolic structure and a photografting catalyst. Under visible light irradiation, the photografting catalyst is activated and undergoes a photochemical reaction with the amino acid side groups on the macromolecular chain structure of the silk fiber to form active grafting sites. Subsequently, the phenolic antibacterial finishing agent diffuses and adsorbs to combine with the silk fiber, and undergoes a covalent reaction with the active grafting sites on the silk, completing the covalent grafting finishing of the phenolic antibacterial finishing agent and the silk. However, the silk fabric treated by this method has poor wash resistance.

[0004] Given the above background, it is still very necessary to develop antibacterial silk fabrics with excellent water resistance. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides an antibacterial silk fabric and its preparation method. First, a dioscorea extract is extracted from the tuber of Dioscorea opposita using a water immersion method. Then, condensed tannin compounds in the dioscorea opposita extract are used as antibacterial components, and zeolite imidazole ester framework material is used as a functional carrier for the dioscorea opposita extract to synthesize a nano-antibacterial material (denoted as SL@ZIF). Finally, the silk fabric is treated with an impregnation method for antibacterial finishing.

[0006] The first objective of this invention is to provide a method for preparing antibacterial silk fabric, comprising the following steps:

[0007] S1. The zeolite imidazole ester framework structure material is dispersed in the yam extract solution, and after stirring, centrifugation and drying, the zeolite imidazole ester framework / yam extract is obtained.

[0008] S2. The silk fabric is immersed in a zeolite imidazole ester skeleton / dioscorea extract finishing solution for finishing to obtain the antibacterial silk fabric; the zeolite imidazole ester skeleton / dioscorea extract finishing solution includes the zeolite imidazole ester skeleton / dioscorea extract described in S1 and water.

[0009] In one embodiment of the present invention, in S1, the zeolite imidazolate framework material is selected from one or more of ZIF-67, ZIF-90, and ZIF-8. Metal-organic frameworks (MOFs) are nanoporous materials assembled from zinc ions and organic ligands through coordination covalent bonds. Zeolite imidazolate framework material is a commonly used MOF, composed of zinc ions and ligands, and exhibits good thermal stability, hydrothermal stability, and excellent biocompatibility. Furthermore, zinc ions possess antibacterial properties, thus showing great application potential in fields such as antibacterial textiles and biomedicine.

[0010] In one embodiment of the present invention, in step S1, the preparation of the Dioscorea bulbifera extract specifically includes the following steps: peeling and chopping fresh Dioscorea bulbifera tubers, adding deionized water at a solid-liquid ratio of 1:(2-3), pulverizing into a slurry, and then, under sealed conditions, water bath shaking extraction at 60℃-65℃ for 2-2.5 hours, followed by standing, layering, filtration, and drying. Based on research on Dioscorea bulbifera tuber extract, it can be generally considered that the main components of Dioscorea bulbifera tuber extract are condensed tannin compounds, which are antibacterial active ingredients. Dioscorea bulbifera extract imparts certain antibacterial properties to silk fabrics, mainly because natural condensed tannin compounds can bind to proteins in bacterial cells through hydrogen bonds, hydrophobic interactions, and covalent bonds, or by disrupting the bacterial cell membrane, thereby effectively inhibiting bacterial growth.

[0011] In one embodiment of the present invention, in S1, the mass ratio of the zeolite imidazole ester framework material to the dioscorea bulbifera extract is 1:(180-220); the concentration of the dioscorea bulbifera extract solution is 180 mg / mL-220 mg / mL. Due to the high surface area and porosity of the zeolite imidazole ester framework material, the dioscorea bulbifera extract can be adsorbed on the surface of the zeolite imidazole ester framework material. The main principle of surface adsorption is the interaction of van der Waals forces, hydrogen bonds, etc.

[0012] In one embodiment of the present invention, in S1, the stirring speed is 140 rpm-160 rpm and the stirring time is 50 min-70 min.

[0013] In one embodiment of the present invention, in S2, the concentration of the zeolite imidazole ester skeleton / Dioscorea opposita extract finishing solution is 30 g / L-100 g / L, and the pH value is 4-6.

[0014] In one embodiment of the present invention, the pH adjuster is selected from citric acid and / or disodium hydrogen phosphate.

[0015] In one embodiment of the present invention, in S2, the bath ratio of the silk fabric and the zeolite imidazole ester skeleton / dioscorea extract finishing solution is 1:(40-50).

[0016] In one embodiment of the present invention, in S2, the finishing process involves heating to 50°C-90°C at a rate of 1.8°C / min-2.2°C / min and holding at that temperature for 50 min-150 min.

[0017] In one embodiment of the present invention, the multiple interactions between the zeolite imidazole ester skeleton / Dioscorea opposita extract and silk fibers include: first, under weakly acidic conditions, there is an ionic interaction between the partially ionized hydroxyl groups in the condensed tannin compound and the protonated amino groups on the silk fiber; second, the hydroxyl groups on the condensed tannin compound can combine with the amino, amide, carboxyl, and hydroxyl groups on the silk fiber to form hydrogen bonds; third, there is also a van der Waals force between the condensed tannin compound and the silk fiber, especially the nonpolar van der Waals force between the benzene ring in the condensed tannin compound and the aromatic ring containing amino acid residues on the silk fiber; fourth, a small amount of the condensed tannin compound and the silk fiber are combined through covalent bonds, such as the hydroxyl groups in the condensed tannin compound reacting with the amino groups on the silk fiber to form covalent bonds.

[0018] A second objective of this invention is to provide an antibacterial silk fabric prepared by the method described above.

[0019] The antibacterial mechanism of this invention is as follows: condensed tannin compounds with antibacterial activity are encapsulated within a zeolite imidazole ester framework material. When silk fabrics are treated with an antibacterial finish using an impregnation method under weakly acidic conditions, the zeolite imidazole ester framework material releases condensed tannin compounds that react with the silk fabric. These condensed tannin compounds can bind to proteins in bacterial cells through hydrogen bonds, hydrophobic interactions, and covalent bonds, or by disrupting the bacterial cell membrane, thereby effectively inhibiting bacterial growth. Furthermore, the zinc ions released by SL@ZIF-8 have antibacterial effects, synergistically enhancing the antibacterial properties of the silk fabric.

[0020] The technical solution of the present invention has the following advantages compared with the prior art:

[0021] (1) The preparation method of the present invention first extracts Dioscorea opposita extract from the tuber of Dioscorea opposita by water immersion, and then uses the condensed tannins in the Dioscorea opposita extract as antibacterial components and the zeolite imidazole ester framework structure material as the functional carrier of Dioscorea opposita extract to synthesize nano-antibacterial material (denoted as SL@ZIF). The zeolite imidazole ester framework structure material loads condensed tannins by surface adsorption, encapsulating the condensed tannins with antibacterial activity within the zeolite imidazole ester framework structure material; finally, the silk fabric is antibacterially treated by impregnation under weakly acidic conditions. The zeolite imidazole ester framework structure material releases condensed tannins that react with the silk fabric. The condensed tannins can bind with proteins in bacterial cells through hydrogen bonds, hydrophobic interactions and covalent bonds or by destroying the bacterial cell membrane, thereby effectively inhibiting bacterial growth; furthermore, the zinc ions released by SL@ZIF have antibacterial effects, which synergistically enhance the antibacterial properties of the silk fabric. SL@ZIF is applied to silk fabrics through ionic bonds, van der Waals forces, hydrogen bonds, and covalent bonding.

[0022] (2) The preparation method described in this invention uses natural raw materials, is convenient and environmentally friendly. Detailed Implementation

[0023] The present invention will be further described below with reference to specific embodiments, so that those skilled in the art can better understand and implement the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. It should be understood that the specific embodiments are only used to explain the present invention, but the embodiments are not intended to limit the present invention.

[0024] In this invention, unless otherwise stated, the technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0025] In this invention, unless otherwise stated, the term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0026] In this invention, unless otherwise specified, the experimental methods used in the embodiments of this invention are conventional methods, and the materials and reagents used are commercially available unless otherwise specified.

[0027] In this invention, unless otherwise stated, the preparation of the Dioscorea bulbifera extract used in the embodiments of this invention specifically includes the following steps: peeling and chopping the fresh Dioscorea bulbifera tubers, adding deionized water at a solid-liquid ratio of 1:2.5, pulverizing the mixture into a slurry, adding it to a sealed conical flask, and extracting it by shaking in a water bath at 60°C for 2 hours. Then, the liquid is allowed to stand and separate into layers, and after cooling to room temperature, it is filtered and dried.

[0028] In this invention, unless otherwise stated, the preparation of ZIF-8 nanoparticles used in the embodiments of this invention specifically includes the following steps: 1713.54 mg of zinc nitrate hexahydrate and 9852 mg of 2-methylimidazole are dissolved in 240 mL of methanol, and sonicated for 20 min to obtain a clear solution; at room temperature, 20 mL of the methanol solution of zinc nitrate hexahydrate is slowly poured into 20 mL of the methanol solution of 2-methylimidazole, and the reaction is carried out under magnetic stirring for 4 h; the product is collected by centrifugation, washed three times with methanol, and dried under vacuum.

[0029] Example 1

[0030] The antibacterial silk fabric and its preparation method in this embodiment specifically include the following steps:

[0031] S1. Disperse 50 mg of ZIF-8 in 50 mL of 200 mg / mL dioscorea bulbifera extract aqueous solution, and stir magnetically at 150 rpm for 60 min. After centrifugation and drying, SL@ZIF-8 is obtained.

[0032] S2. Disperse SL@ZIF-8 in water to obtain a SL@ZIF-8 finishing solution with a concentration of 30 g / L; immerse the silk fabric in the SL@ZIF-8 finishing solution for finishing, with a bath ratio of 1:50, and adjust the pH of the SL@ZIF-8 finishing solution to 4.5 using a citric acid / disodium hydrogen phosphate buffer solution; heat from 30℃ to 60℃ at a rate of 2℃ / min and hold for 120 min, rinse with deionized water and air dry to obtain an antibacterial silk fabric.

[0033] Example 2

[0034] The antibacterial silk fabric and its preparation method in this embodiment specifically include the following steps:

[0035] S1. Disperse 50 mg of ZIF-8 in 50 mL of 200 mg / mL dioscorea bulbifera extract aqueous solution, and stir magnetically at 150 rpm for 60 min. After centrifugation and drying, SL@ZIF-8 is obtained.

[0036] S2. Disperse SL@ZIF-8 in water to obtain a SL@ZIF-8 finishing solution with a concentration of 100 g / L; immerse the silk fabric in the SL@ZIF-8 finishing solution for finishing, with a liquor ratio of 1:50, and adjust the pH of the SL@ZIF-8 finishing solution to 5 using a citric acid / disodium hydrogen phosphate buffer solution; heat from 30℃ to 70℃ at a rate of 2℃ / min and hold for 100 min, rinse with deionized water and air dry to obtain an antibacterial silk fabric.

[0037] Example 3

[0038] The antibacterial silk fabric and its preparation method in this embodiment specifically include the following steps:

[0039] S1. Disperse 50 mg of ZIF-8 in 50 mL of 200 mg / mL dioscorea bulbifera extract aqueous solution, and stir magnetically at 150 rpm for 60 min. After centrifugation and drying, SL@ZIF-8 is obtained.

[0040] S2. Disperse SL@ZIF-8 in water to obtain an SL@ZIF-8 finishing solution with a concentration of 80 g / L; immerse the silk fabric in the SL@ZIF-8 finishing solution for finishing, with a liquor ratio of 1:50, and adjust the pH of the SL@ZIF-8 finishing solution to 5.5 using a citric acid / disodium hydrogen phosphate buffer solution; heat from 30℃ to 80℃ at a rate of 2℃ / min and hold for 90 min, rinse with deionized water and air dry to obtain an antibacterial silk fabric.

[0041] Example 4

[0042] The antibacterial silk fabric and its preparation method in this embodiment specifically include the following steps:

[0043] S1. Disperse 50 mg of ZIF-8 in 50 mL of 200 mg / mL dioscorea bulbifera extract aqueous solution, and stir magnetically at 150 rpm for 60 min. After centrifugation and drying, SL@ZIF-8 is obtained.

[0044] S2. Disperse SL@ZIF-8 in water to obtain a SL@ZIF-8 finishing solution with a concentration of 50 g / L; immerse the silk fabric in the SL@ZIF-8 finishing solution for finishing, with a liquor ratio of 1:50, and adjust the pH of the SL@ZIF-8 finishing solution to 4.5 using a citric acid / disodium hydrogen phosphate buffer solution; heat from 30℃ to 90℃ at a rate of 2℃ / min and hold for 70 min, rinse with deionized water and air dry to obtain an antibacterial silk fabric.

[0045] Comparative Example 1

[0046] The process is basically the same as in Example 1, except that ZIF-8 is not added. The specific steps include:

[0047] The silk fabric was treated by immersing it in an aqueous solution of Dioscorea bulbifera extract with a concentration of 200 mg / mL at a liquor ratio of 1:50. The pH of the aqueous solution of Dioscorea bulbifera extract was adjusted to 4.5 using a citric acid / disodium hydrogen phosphate buffer solution. The temperature was increased from 30°C to 60°C at a rate of 2°C / min and held for 120 min. The fabric was then rinsed with deionized water and air-dried to obtain the antibacterial silk fabric.

[0048] Test case

[0049] The antibacterial properties of the antibacterial silk fabrics prepared in Examples 1-4 and Comparative Example 1 were tested:

[0050] Antibacterial properties: The antibacterial rate of antibacterial silk fabrics was tested according to GB / T 20944.3-2008 "Evaluation of antibacterial properties of textiles - Part 3: Vibration method".

[0051] Wash resistance: The wash resistance of antibacterial silk fabrics was tested according to AATCC 124-2006 "Determination of the smoothness of appearance of fabrics after multiple household washes".

[0052] Table 1 shows the relevant properties of the finally measured modified silk fabric:

[0053] Table 1

[0054]

[0055]

[0056] As can be seen from Table 1, the antibacterial silk fabrics of the embodiments have good antibacterial properties and wash resistance. Comparing Example 1 and Comparative Example 1, it can be seen that the method of Example 1 improves the antibacterial rate of the antibacterial silk fabric after 50 washes, and the antibacterial silk fabric has good antibacterial durability.

[0057] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for preparing an antibacterial silk fabric, characterized in that, Includes the following steps: S1. The zeolite imidazole ester framework structural material is dispersed in the yam extract solution, and after stirring, centrifugation and drying, the zeolite imidazole ester framework / yam extract is obtained; the mass ratio of the zeolite imidazole ester framework structural material to the yam extract is 1:(180-220); the concentration of the yam extract solution is 180mg / mL-220mg / mL; the preparation of the yam extract specifically includes the following steps: peeling and chopping the fresh yam tubers, adding deionized water at a solid-liquid ratio of 1:(2-3), pulverizing into a slurry, and then, under sealed conditions, water bath shaking extraction at 60℃-65℃ for 2h-2.5h, followed by standing, layering, filtration and drying; S2. The silk fabric is immersed in a zeolite imidazole ester skeleton / dioscorea extract finishing solution for finishing to obtain the antibacterial silk fabric; the zeolite imidazole ester skeleton / dioscorea extract finishing solution includes the zeolite imidazole ester skeleton / dioscorea extract described in S1 and water; the concentration of the zeolite imidazole ester skeleton / dioscorea extract finishing solution is 30g / L-100g / L, and the pH value is 4-6.

2. The method for preparing antibacterial silk fabric according to claim 1, characterized in that, In S1, the zeolite imidazole ester framework material is selected from one or more of ZIF-67, ZIF-90 and ZIF-8.

3. The method for preparing antibacterial silk fabric according to claim 1, characterized in that, In S1, the stirring speed is 140 rpm-160 rpm, and the stirring time is 50 min-70 min.

4. The method for preparing antibacterial silk fabric according to claim 1, characterized in that, The pH adjuster is selected from citric acid and / or disodium hydrogen phosphate.

5. The method for preparing antibacterial silk fabric according to claim 1, characterized in that, In S2, the bath ratio of the silk fabric and the zeolite imidazole ester skeleton / dioscorea extract finishing solution is 1:(40-50).

6. The method for preparing antibacterial silk fabric according to claim 1, characterized in that, In S2, the finishing process involves heating to 50℃-90℃ at a rate of 1.8℃ / min-2.2℃ / min and holding at that temperature for 50min-150min.

7. Antibacterial silk fabric prepared by the method according to any one of claims 1-6.

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