Sodium alginate particle coated with chitosan with micro-nano structure as well as preparation and application of sodium alginate particle

Abstract

The invention belongs to the field of harm-reducing materials for cigarettes, and particularly relates to a sodium alginate particle coated with chitosan with a micro-nano structure as well as preparation and application of the sodium alginate particle. The preparation method comprises the following steps: 1) mixing a chitosan solution with anhydrous calcium chloride to obtain a coagulating bath; 2) dropwise adding a sodium alginate solution into the coagulating bath to obtain hydrogel pellets; and (3) drying the hydrogel beads to obtain the sodium alginate particles coated with the chitosan with the micro-nano structure. The method for preparing the sodium alginate core-shell particles of the chitosan with the micro-nano structure is simple and easy to implement, low in production cost, free of environmental pollution and mild and easy-to-control in condition, the structure of the obtained sodium alginate core-shell particles of the chitosan with the micro-nano structure is adjustable, and the content of phenol and crotonaldehyde in mainstream smoke of cigarettes is effectively reduced.

Description

Technical Field

[0001] The invention belongs to the field of tobacco harm reduction materials, and specifically relates to sodium alginate particles coated with micro-nano structure chitosan, and preparation and application thereof. Background Art

[0002] In addition to tobacco aroma components, there are also a large number of harmful components in cigarette smoke. Effectively retaining the aroma components in cigarette smoke while removing harmful components to the greatest extent is the common pursuit of cigarette manufacturers and cigarette consumers. Studies have shown that some compounds with amino, urea or amide groups have good adsorption effects on carbonyl compounds in smoke. Studies have shown that porous silica gel materials modified with polyethyleneimine and amino-modified activated carbon can remove a large amount of crotonaldehyde in mainstream cigarette smoke. The adsorption of crotonaldehyde conforms to pseudo-second-order kinetics and is affected by intraparticle diffusion. However, polyethyleneimine materials are chemically synthesized materials, and their use in cigarettes is restricted by the list of tobacco licenses. In addition, due to the effect of viscous resistance, the diffusion efficiency of microfluids in micro- and mesoporous channels is low, and the utilization efficiency of amino groups modified in the channels is low. Summary of the invention

[0003] In order to solve the above technical problems, the present invention provides a method for preparing sodium alginate particles coated with micro-nanostructure chitosan, particles produced by the method and applications. The method for preparing sodium alginate core-shell particles of micro-nanostructure chitosan of the present invention has simple and easy steps, low production cost and no environmental pollution. The structure of the obtained sodium alginate core-shell particles of micro-nanostructure chitosan can be adjusted, and the content of phenol and crotonaldehyde in mainstream cigarette smoke is effectively reduced.

[0004] In a first aspect, the present invention provides a method for preparing sodium alginate particles coated with micro-nanostructure chitosan, comprising:

[0005] 1) Mix the chitosan solution with anhydrous calcium chloride to obtain a coagulation bath.

[0006] 2) Adding sodium alginate solution drop by drop into the coagulation bath to obtain hydrogel beads.

[0007] 3) Drying the hydrogel beads to obtain sodium alginate particles coated with micro-nanostructured chitosan.

[0008] The preparation method provided by the present invention is based on the solvent-induced phase separation mechanism to construct a sodium alginate particle coated with chitosan of micro-nano structure. Both chitosan and sodium alginate are natural materials and do not have the safety risk of tobacco materials. Each structural unit of chitosan natural polymer material contains an amino group. The present invention can greatly increase the contact area between chitosan and smoke by constructing a complex micro-nano structure, thereby achieving efficient adsorption of smoke components. The material preparation method is simple, the raw materials are cheap and easy to obtain, the conditions are mild and easy to control, and the surface structure is adjustable, which overcomes the potential safety risks and diffusion resistance of existing amino-modified porous materials.

[0009] Preferably, in step 1), the mass ratio of the chitosan solution to the anhydrous calcium chloride is 95-120 mL: 1 g, preferably 100 mL: 1 g. The above ratio optimizes the stability and cross-linking effect of the coagulation bath and ensures the uniformity and adsorption performance of the micro-nano structure.

[0010] Preferably, in step 1), the preparation of the chitosan solution comprises mixing and stirring chitosan with acetic acid solution to obtain a chitosan solution.

[0011] More preferably, the mass volume ratio of the chitosan to the acetic acid solution is 0.01-2 g:100 mL, preferably 0.5-2 g:100 mL.

[0012] Further preferably, the concentration of the acetic acid solution is 0.05-2 mol / L, preferably 0.1-0.2 mol / L. The preferred mass volume ratio of chitosan to acetic acid solution and the concentration of acetic acid solution of the present invention ensure the appropriate viscosity and solubility of the chitosan solution, facilitate the subsequent solidification and molding process, and ultimately improve the quality and comprehensive performance of the micro-nano structure.

[0013] Preferably, in step 2), the concentration of the sodium alginate solution is 12-18 g / L, preferably 15-16 g / L. In the present invention, by optimizing the concentration to obtain a clear and viscous sodium alginate aqueous solution, the sodium alginate particles coated with micro-nanostructure chitosan can be better prepared, especially at 15-16 g / L. This concentration range optimizes the viscosity of sodium alginate, so that it forms more uniform hydrogel spheres in the coagulation bath, ensuring the formation and stability of the micro-nanostructure.

[0014] Preferably, in step 3), the sodium alginate droplets are treated in the coagulation bath for 20 to 40 minutes. The optimal treatment time ensures sufficient reaction, forms a stable micro-nano structure, and further improves the adsorption performance of the material.

[0015] The micro-nanostructured chitosan sodium alginate particles prepared by the method have high-efficiency adsorption performance and good stability, are more suitable for cigarette filter rods and can effectively remove harmful components phenol and crotonaldehyde in mainstream cigarette smoke, and can also improve the safety and taste of cigarettes.

[0016] In a second aspect, the present invention provides sodium alginate particles coated with micro-nanostructure chitosan obtained by the preparation method of sodium alginate particles coated with micro-nanostructure chitosan.

[0017] In a third aspect, the present invention provides the use of the sodium alginate particles coated with micro-nanostructured chitosan obtained by the preparation method or the sodium alginate particles coated with micro-nanostructured chitosan in cigarettes, preferably in cigarette filter rods, and more preferably for removing harmful components phenol and crotonaldehyde in mainstream cigarette smoke.

[0018] In a fourth aspect, the present invention provides a cigarette filter rod, comprising the sodium alginate particles coated with micro-nanostructure chitosan obtained by the preparation method or the sodium alginate particles coated with micro-nanostructure chitosan. The present invention provides a cigarette filter rod comprising the micro-nanostructure chitosan sodium alginate particles, which can not only significantly reduce harmful components in smoke, but also maintain a good smoking experience, providing consumers with a healthier choice.

[0019] The method for preparing sodium alginate core-shell particles of micro-nanostructure chitosan of the present invention has simple and easy steps, low production cost and no environmental pollution. The structure of the obtained sodium alginate core-shell particles of micro-nanostructure chitosan can be adjusted, and the content of phenol and crotonaldehyde in mainstream cigarette smoke can be effectively reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 Fourier transform infrared spectra of particles prepared from five chitosan solutions prepared in Example 1.

[0022] Figure 2 Scanning electron micrographs of particles prepared from five chitosan solutions prepared in Example 1.

[0023] Figure 3 The scanning electron microscope characterization results of the changes in the surface morphology of the particles after different numbers of puffs in Example 2.

[0024] Figure 4These are the scanning electron microscope characterization results of the changes in the surface morphology of the particles before suction, after suction, and after ultrasonic cleaning with methanol after suction in Example 2, and the carbon spectrum results of the surface X-ray photoelectron spectroscopy test. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] In the embodiment of the present invention, the sodium alginate particles coated with micro-nanostructure chitosan are evaluated for adsorbing harmful components of mainstream cigarette smoke by adding the material to a cigarette filter rod and then smoking. The adsorption performance of the material is evaluated by scanning electron microscopy, X-ray photoelectron spectroscopy, and high performance liquid chromatography quantitative analysis.

[0027] In the embodiment of the present invention, the Fourier transform infrared spectrum was measured using a German Bruker VERTEX 70 infrared spectrometer with a wavelength range of 4000-400 cm -1 , attenuated total reflection mode test, cumulative scan 32 times, spectral resolution 4 cm -1 .

[0028] In the embodiment of the present invention, the scanning electron microscope is tested by using a Sigma300 field emission scanning electron microscope produced by Zeiss of Germany; the sample is subjected to gold spraying before the test, and the accelerating voltage is 20 kV.

[0029] In the embodiment of the present invention, the carbon spectrum of the X-ray photoelectron spectroscopy test is tested using an ESCALABXI+ X-ray photoelectron spectrometer produced by ThermoFisher Scientific.

[0030] Example 1

[0031] Weigh 0.3g of sodium alginate and add it to 20ml of deionized water and stir until completely dissolved to obtain a viscous and clear sodium alginate solution. Weigh 0, 0.5g, 1.0g, 1.5g, and 2.0g of chitosan, add them to 100mL of 0.1mol / L acetic acid solution and stir until completely dissolved, add 1g of anhydrous calcium chloride and continue stirring until completely dissolved to obtain 5 coagulation baths. Add the sodium alginate solution drop by drop into the 5 coagulation baths. After the addition is complete, balance in the coagulation bath for 30min to obtain transparent gel balls. Put it in an oven and dry it at 80℃. The 5 dried particles prepared in the 5 coagulation baths prepared with 0, 0.5g, 1.0g, 1.5g, and 2.0g chitosan are named 0 CS, 0.5% CS, 1.0% CS, 1.5% CS, and 2.0% CS.

[0032] The five particles were characterized by Fourier transform infrared spectroscopy. Figure 1 The characteristic infrared absorption band intensity of sodium alginate (1120 cm -1 , 1082 cm -1 、940 cm -1 、818 cm -1 ) gradually weakened with the increase of chitosan concentration in the coagulation bath, indicating that chitosan was successfully coated on the surface of sodium alginate particles.

[0033] The characterization results of the five particles by scanning electron microscopy are shown in Figure 2 The chitosan microstructure on the particle surface exhibits obvious micro-nano wrinkled structures, and the micro-nano structures tend to be richer with the increase of chitosan concentration in the coagulation bath.

[0034] Example 2

[0035] A 1.0% CS sample was prepared according to the method of Example 1. Seven portions of 20 mg of dried particles were weighed and added to filter rods of a certain brand of cigarettes. A syringe was used to simulate puffing to obtain particle samples after different numbers of puffs. The particles after 7 puffs were ultrasonically cleaned 3 times with anhydrous methanol.

[0036] Figure 3 The morphological changes of particles after different numbers of puffs of cigarettes. As the number of puffs increases, the micro-nano structure of the particle surface gradually changes, indicating that the particles can effectively adsorb the mainstream smoke of cigarettes during the entire puffing process.

[0037] Figure 4The scanning electron microscope images of the particles before puffing, after 7 puffs, and after cleaning, and the carbon element spectrum characterized by X-ray photoelectron spectroscopy. After cleaning, the micro-nano structure of the particles is retained to a certain extent, indicating that physical adsorption is an important form of particle adsorption of mainstream cigarette smoke. At the same time, the characterization results of carbon elements by X-ray photoelectron spectroscopy show that the chemical environment of carbon elements has changed significantly, which to a certain extent indicates that the surface functional groups of the particles have chemically adsorbed the mainstream smoke components.

[0038] Example 3

[0039] The 0CS and 1.0% CS samples were prepared according to the method of Example 1. 20 mg of sample particles were weighed and added to a cigarette filter rod with a tar content of 5 mg of a certain brand. A linear smoking machine (SM450, Cerulean, UK) was used to perform a cigarette smoking test to capture the total particulate matter in the mainstream smoke. The contents of phenol and crotonaldehyde in the mainstream smoke were quantitatively analyzed according to the tobacco industry standards YC / T 254 and YC / T 255. The phenol and crotonaldehyde in the mainstream smoke of the cigarette with the 0CS sample added were 7.41 μg / cig and 12.35 μg / cig, respectively, and the phenol and crotonaldehyde in the mainstream smoke of the cigarette with the 1.0% CS sample added were 6.79 μg / cig and 11.17 μg / cig, respectively.

[0040] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing sodium alginate particles coated with micro-nanostructure chitosan, characterized in that: include: 1) mixing the chitosan solution with anhydrous calcium chloride to obtain a coagulation bath; 2) dripping the sodium alginate solution into the coagulation bath drop by drop to obtain hydrogel beads; 3) Drying the hydrogel beads to obtain sodium alginate particles coated with micro-nanostructured chitosan.

2. The method for preparing sodium alginate particles coated with micro-nanostructure chitosan according to claim 1, characterized in that: In step 1), the mass ratio of the chitosan solution to the anhydrous calcium chloride is 95-120 mL: 1 g.

3. The method for preparing sodium alginate particles coated with micro-nanostructure chitosan according to claim 2, characterized in that: In step 1), the preparation of the chitosan solution includes mixing and stirring chitosan and acetic acid solution to obtain a chitosan solution.

4. The method for preparing sodium alginate particles coated with micro-nanostructure chitosan according to claim 3, characterized in that: The mass volume ratio of the chitosan to the acetic acid solution is 0.01-2 g:100 mL.

5. The method for preparing sodium alginate particles coated with micro-nanostructure chitosan according to claim 4, characterized in that: The concentration of the acetic acid solution is 0.05-2 mol / L, preferably 0.1-0.2 mol / L.

6. The method for preparing sodium alginate particles coated with micro-nanostructure chitosan according to any one of claims 1 to 5, characterized in that: In step 2), the concentration of the sodium alginate solution is 12-18 g / L.

7. The method for preparing sodium alginate particles coated with micro-nanostructure chitosan according to any one of claims 1 to 6, characterized in that: In step 3), the sodium alginate droplets are equilibrated in the coagulation bath for 20 to 40 minutes.

8. Sodium alginate particles coated with micro-nanostructure chitosan obtained by the method for preparing sodium alginate particles coated with micro-nanostructure chitosan according to any one of claims 1 to 7.

9. Use of the sodium alginate particles coated with micro-nanostructure chitosan obtained by the preparation method according to any one of claims 1 to 7 or the sodium alginate particles coated with micro-nanostructure chitosan according to claim 8 in cigarettes, preferably in cigarette filter rods, more preferably for removing harmful components phenol and crotonaldehyde in mainstream cigarette smoke.

10. A cigarette filter rod, characterized in that: The invention comprises the sodium alginate particles coated with micro-nanostructure chitosan obtained by the preparation method according to any one of claims 1 to 7 or the sodium alginate particles coated with micro-nanostructure chitosan according to claim 8.

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