Preparation method and application of CS / PVA-AgNPS antibacterial material

Abstract

The invention discloses a preparation method and application of a CS / PVA-AgNPS antibacterial material. The preparation method of the antibacterial material comprises the following steps: preparing a silver nitrate solution; pDDA is added into the silver nitrate solution; dropwise adding a hydrazine hydrate solution into the PDDA-dissolved silver ion solution to obtain a nano-silver suspension, cleaning to obtain an AgNPS solution, centrifuging the AgNPS solution to remove supernatant, and drying to obtain nano-silver particles; adding CS into an acetic acid solution to prepare a solution; completely dissolving PVA and distilled water; the method comprises the following steps: blending a CS solution and a PVA aqueous solution, and heating and stirring to obtain a CS / PVA mixed solution; and adding the nano-silver particles into the CS / PVA mixed solution, and continuously stirring in the adding process to obtain the CS / PVA-AgNPS antibacterial material. The CS / PVA-AgNPS antibacterial material disclosed by the invention can effectively kill microorganisms such as saccharomycetes and molds and prolong the shelf life of flavors and fragrances while the perfuming effect of the flavors and fragrances is not influenced, and has the advantages of low temperature, short time, good effect, no pollution and the like.

Description

Technical Field

[0001] The invention relates to the technical field of tobacco, and in particular to a preparation method and application of a CS / PVA-AgNPS antibacterial material. Background Art

[0002] Cigarette flavoring technology is one of the core technologies of cigarette manufacturers. It can affect and change the quality and style of cigarette products. Due to the limitations of process conditions, flavors and fragrances are inevitably exposed to microorganisms in the air during the production process, especially natural fragrance raw materials. When stored for a long time, the quality of flavors and fragrances is easily affected. Therefore, the quality stability of flavors and fragrances is the focus of tobacco industry research.

[0003] Nano antibacterial materials are new and highly effective sterilization materials that have emerged in recent years. They have the advantages of being resistant to aging, high temperature, corrosion, stable antibacterial properties, and easy to apply on a large scale. As a highly effective sterilization material, nanosilver has been widely studied and applied in the field of drinking water sterilization because of its safety, efficiency, practicality, and recyclability.

[0004] Therefore, the CS / PVA-AgNPS antibacterial film prepared in the present invention can effectively kill microorganisms such as yeast and mold without affecting the flavoring effect of flavors and spices, and extend the shelf life of flavors and spices. It has the advantages of low temperature, short time, good effect, and no pollution. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a preparation method and application of CS / PVA-AgNPS antibacterial material, so as to solve the problem that tobacco flavors and fragrances are easily contaminated by microorganisms during the production and processing. The antibacterial material of the present application can effectively kill microorganisms such as yeast and mold, and extend the shelf life of flavors and fragrances.

[0006] The technical problem to be solved by the present invention is achieved through the following technical solutions:

[0007] A method for preparing a CS / PVA-AgNPS antibacterial material comprises the following steps:

[0008] (1) dissolving silver nitrate in deionized water to prepare a silver nitrate solution; adding polydiallyldimethylammonium chloride (PDDA) dropwise to the silver nitrate solution under stirring, and continuing stirring for 30 minutes;

[0009] (2) slowly dripping the hydrazine hydrate solution into the silver ion solution containing PDDA in step (1), stirring while dripping, reacting at room temperature for 4 hours, to obtain a nanosilver suspension, washing with deionized water to obtain an AgNPS solution, centrifuging the AgNPS solution to remove the supernatant, and vacuum drying to obtain nanosilver particles;

[0010] (3) chitosan (CS) was added to the acetic acid solution to prepare a solution for standby use; PVA was completely dissolved in distilled water and set aside for standby use; the CS solution and the PVA aqueous solution were mixed at a volume ratio of 1:3, heated and stirred at 60° C. for 1 h to obtain a CS / PVA mixed solution;

[0011] (4) Slowly adding the silver nanoparticles into the CS / PVA mixed solution and continuously stirring during the adding process to obtain the CS / PVA-AgNPS antibacterial material.

[0012] Preferably, the above technical solution further includes:

[0013] (5) The CS / PVA-AgNPS antibacterial material was poured into a mold and dried in an oven at 60°C for 5 h to obtain a CS / PVA antibacterial film. The antibacterial film was cut into squares and placed in a double-sided filter interlayer for sterilization of flavors and fragrances.

[0014] Preferably, in the above technical solution, in step (1), the mass ratio of the silver nitrate to the deionized water is 1:1, and the amount of PDDA added does not exceed 2% of the mass of the silver nitrate solution.

[0015] Preferably, in the above technical solution, the concentration of the hydrazine hydrate solution in step (2) is 10%, and the volume ratio of the hydrazine hydrate solution to the silver nitrate solution is 1:2; the centrifugation conditions are: 15000 rpm, 30 min; and the drying conditions are: drying in a vacuum drying oven at 45°C for 2 h.

[0016] Preferably, in the above technical solution, in step (3), the mass fraction of the chitosan (CS) solution is 2%; and the mass ratio of PVA to distilled water is 1:10.

[0017] Preferably, in the above technical solution, in step (4), the mass ratio of nanosilver particles to CS / PVA is 1:4; and the speed of continuous stirring is 600 rpm.

[0018] A sterilization device for tobacco flavors and fragrances comprises a double-sided filter and a CS / PVA-AgNPS antibacterial material layer, wherein the CS / PVA-AgNPS antibacterial material layer is sandwiched between two layers of double-sided filter, and the CS / PVA-AgNPS antibacterial material layer is a square antibacterial film of 8×8 cm.

[0019] Application of CS / PVA-AgNPS antibacterial material in the sterilization of tobacco flavors and fragrances.

[0020] Preferably, in the above technical solution, the application is to sterilize tobacco flavors and fragrances using CS / PVA-AgNPS antibacterial materials, comprising the following steps:

[0021] (1) Pour the CS / PVA-AgNPS antibacterial material into a mold and dry it in an oven at 60 °C for 5 h to obtain a CS / PVA antibacterial film;

[0022] (2) The antibacterial film was cut into 8 × 8 cm squares and placed in a homemade double-sided filter sandwich as a flavor and fragrance sterilization device;

[0023] (3) Place the sterilization device directly into the flavors and spices to be sterilized, stir slowly for 30 minutes, rinse after sterilization, dry at 45°C, and seal for storage.

[0024] The above technical solution of the present invention has the following beneficial effects:

[0025] The CS / PVA-AgNPS antibacterial material of the present application can effectively kill microorganisms such as yeast and mold without affecting the fragrance effect of flavors and spices, and extend the shelf life of flavors and spices. It has the advantages of low temperature, short time, good effect, and no pollution. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

[0027] Figure 1 Schematic diagram of the CS / PVA-AgNPS flavor and fragrance sterilization device.

[0028] Figure 2 This is the microbial status of samples A and B on the 7th day. DETAILED DESCRIPTION

[0029] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that the relative arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present invention unless otherwise specifically stated.

[0030] Unless otherwise specified, the reagents used in this application are all commercially available or obtained through commercial channels, or can be prepared by referring to existing chemical methods.

[0031] Embodiment 1 Sterilization device for tobacco flavors and fragrances

[0032] A sterilization device for tobacco flavors and fragrances comprises a double-sided filter 201 and a CS / PVA-AgNPS antibacterial material layer 202, wherein the CS / PVA-AgNPS antibacterial material layer 202 is sandwiched between two layers of double-sided filter 201, and the CS / PVA-AgNPS antibacterial material layer 202 is a square antibacterial film of 8×8 cm.

[0033] Example 2 Preparation of CS / PVA-AgNPS antibacterial material

[0034] (1) Weigh 50 g of silver nitrate and dissolve it in 50 g of deionized water to prepare a silver nitrate solution. Add PDDA dropwise to the silver nitrate solution under stirring. The amount added should not exceed 2% of the mass of the silver nitrate solution. Stir continuously for 30 min for later use.

[0035] (2) Weigh 5 g of hydrazine hydrate, dissolve it in 45 mL of deionized water and slowly drip it into the silver ion solution containing PDDA, stirring while adding, and react at room temperature for 4 hours to obtain a nanosilver suspension, which is washed three times with deionized water to obtain an AgNPS solution; use a high-speed centrifuge to centrifuge the AgNPS solution (speed of 15000 rpm, time of 30 min) to remove the supernatant and then dry it in a vacuum drying oven at 45°C for 2 hours to obtain nanosilver particles.

[0036] (3) Weigh 2 g of chitosan (CS) and add it to an acetic acid solution to prepare a mass fraction of 2% for later use; completely dissolve PVA and distilled water at a mass ratio of 1:10 for later use; blend the CS solution and the PVA aqueous solution at a volume ratio of 1:3, and heat and stir at 60°C for 1 h to obtain a mixed solution.

[0037] (4) Slowly adding the nanosilver particles into the CS / PVA mixed solution to obtain the CS / PVA-AgNPS antibacterial material, the mass ratio of the nanosilver particles to the CS / PVA is 1:4, and continuous stirring is performed during the addition process at a rotation speed of 600 rpm to obtain the CS / PVA-AgNPS antibacterial material.

[0038] Example 3 Sterilization treatment

[0039] A certain amount of CS / PVA-AgNPS antibacterial material was poured into a homemade mold to make a sterilization device, and dried in an oven at 60°C for 5 hours to obtain a CS / PVA antibacterial film. The antibacterial film was cut into 8×8 cm squares and placed in a homemade double-sided filter sandwich as a flavor and fragrance sterilization device.

[0040] The above-mentioned sterilization device of the present application may be the sterilization device of Example 1, and of course may also be a sterilization device with the same or similar functions, and the present application is not limited thereto).

[0041] Application Example 1

[0042] 1. Preparation of apricot extract:

[0043] Weigh 200 g of fresh pitted apricot flesh, cut it into pieces, mix it in a mass ratio of apricot flesh: water = 1:10, perform ultrasonic extraction, and obtain apricot extract after filtering;

[0044] 2. The prepared apricot extract was divided into two parts, one of which was sample A without any sterilizing material, and the other was sample B after being treated with a homemade CS / PVA-AgNPS sterilizing device for 30 minutes.

[0045] 3. The CS / PVA-AgNPS sterilization device can be directly placed in the apricot extract and slowly stirred for 30 minutes. After sterilization, it can be simply rinsed and dried at 45°C and sealed for storage. It has the advantages of high sterilization efficiency, easy use, and reusable.

[0046] 4. Take appropriate amount of samples A and B respectively, seal and store the two groups of samples at room temperature of 25℃, and take samples on the 7th day to determine the total number of colonies according to GB 4789.2-2016 "Determination of total number of colonies in food microbiology examination". The results are shown in Figure 2 .

[0047] 5. Sensory evaluation: Samples A and B were injected into blank cigarettes at a ratio of 0.05% and kept at a constant temperature for 48 hours. Sensory evaluation was performed in comparison with the blank control sample. The evaluation results are shown in Table 1.

[0048] Table 1 Sensory evaluation results

[0049]

[0050] Evaluation results: After sterilization, the sensory effect of apricot extract in cigarettes remained almost unchanged, indicating that sterilization had little effect on the flavor components and met the requirements of consistency evaluation.

[0051] Although the present invention has been disclosed as above by the embodiments, it is not intended to limit the present invention. Any person skilled in the art may make various choices and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention is limited by the claims and their equivalents.

Claims

1. A method for preparing a CS / PVA-AgNPS antibacterial material, characterized in that: The following steps are involved: (1) dissolving silver nitrate in deionized water to prepare a silver nitrate solution; adding polydiallyldimethylammonium chloride (PDDA) dropwise to the silver nitrate solution under stirring, and continuing stirring for 30 minutes; (2) slowly dripping the hydrazine hydrate solution into the silver ion solution containing PDDA in step (1), stirring while dripping, reacting at room temperature for 4 hours, to obtain a nanosilver suspension, washing with deionized water to obtain an AgNPS solution, centrifuging the AgNPS solution to remove the supernatant, and vacuum drying to obtain nanosilver particles; (3) chitosan (CS) was added to the acetic acid solution to prepare a solution for standby use; PVA was completely dissolved in distilled water and set aside for standby use; the CS solution and the PVA aqueous solution were mixed at a volume ratio of 1:3, heated and stirred at 60° C. for 1 h to obtain a CS / PVA mixed solution; (4) Slowly adding the silver nanoparticles into the CS / PVA mixed solution and continuously stirring during the adding process to obtain the CS / PVA-AgNPS antibacterial material.

2. The method for preparing the CS / PVA-AgNPS antibacterial material according to claim 1, characterized in that: Also includes: (5) The CS / PVA-AgNPS antibacterial material was poured into a mold and dried in an oven at 60°C for 5 h to obtain a CS / PVA antibacterial film. The antibacterial film was cut into squares and placed in a double-sided filter interlayer for sterilization of flavors and fragrances.

3. The method for preparing the CS / PVA-AgNPS antibacterial material according to claim 1, characterized in that: In step (1), the mass ratio of the silver nitrate to the deionized water is 1:1, and the amount of PDDA added does not exceed 2% of the mass of the silver nitrate solution.

4. The method for preparing the CS / PVA-AgNPS antibacterial material according to claim 1, characterized in that: The concentration of the hydrazine hydrate solution in step (2) is 10%, and the volume ratio of the hydrazine hydrate solution to the silver nitrate solution is 1:2; the centrifugal conditions are: 15000rpm, 30min; and the drying conditions are: drying in a vacuum drying oven at 45°C for 2h.

5. The method for preparing the CS / PVA-AgNPS antibacterial material according to claim 1, characterized in that: In step (3), the mass fraction of the chitosan (CS) solution is 2%; the mass ratio of PVA to distilled water is 1:

10.

6. The method for preparing the CS / PVA-AgNPS antibacterial material according to claim 1, characterized in that: In step (4), the mass ratio of nanosilver particles to CS / PVA is 1:4; and the speed of continuous stirring is 600 rpm.

7. A sterilization device for tobacco flavors and fragrances, characterized in that: The invention comprises a double-sided filter (201) and a CS / PVA-AgNPS antibacterial material layer (202), wherein the CS / PVA-AgNPS antibacterial material layer (202) is sandwiched between two layers of double-sided filter (201), and the CS / PVA-AgNPS antibacterial material layer (202) is a square antibacterial film of 8×8 cm.

8. Use of the CS / PVA-AgNPS antibacterial material according to any one of claims 1 to 6 in sterilizing tobacco flavors and fragrances.

9. The use according to claim 8, characterized in that: The application is to sterilize tobacco flavors and fragrances using CS / PVA-AgNPS antibacterial materials, comprising the following steps: (1) Pour the CS / PVA-AgNPS antibacterial material into a mold and dry it in an oven at 60 °C for 5 h to obtain a CS / PVA antibacterial film; (2) The antibacterial film was cut into 8 × 8 cm squares and placed in a homemade double-sided filter sandwich as a flavor and fragrance sterilization device; (3) Place the sterilization device directly into the flavors and spices to be sterilized, stir slowly for 30 minutes, rinse after sterilization, dry at 45°C, and seal for storage.

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