Antibacterial shampoo and method for preparing the same

Abstract

This invention relates to the field of shampoo technology, and discloses an antibacterial shampoo and its preparation method. The antibacterial shampoo is prepared from deionized water, disodium ethylenediaminetetraacetate, polyquaternium-10, sodium lauryl ether sulfate aqueous solution, cocamidopropyl betaine aqueous solution, an antibacterial agent, dimethyl silicone oil, phenoxyethanol, sodium chloride, fragrance, and citric acid aqueous solution. The antibacterial agent is obtained by spray drying a mixture of aminated graphene quantum dots, quaternized chitosan powder, modified lithium saponite powder, and deionized water. The modified lithium saponite powder is prepared from lithium saponite powder, deionized water, and a hexadecyltrimethylammonium bromide ethanol solution. The quaternized chitosan powder is prepared from chitosan powder, acetic acid aqueous solution, 2,3-epoxypropyltrimethylammonium chloride aqueous solution, and sodium hydroxide aqueous solution. The aminated graphene quantum dots are prepared from L-histidine, citric acid monohydrate, and deionized water. This invention exhibits excellent antibacterial properties.

Description

Technical Field

[0001] This invention relates to the field of shampoo technology, specifically to an antibacterial shampoo and its preparation method. Background Technology

[0002] Shampoo, also known as hair wash, hair lotion, or hair cream, is the most widely used hair care product and one of the most commonly used hair cosmetics. It is used to cleanse the scalp and hair of bodily oils, sweat, shed scalp cells, as well as external dust, microorganisms, styling product residue, and unpleasant odors, keeping the scalp and hair clean and maintaining their appearance.

[0003] Patent CN110840762A discloses a shampoo containing camellia seed extract and its preparation method. In addition to the conventional shampoo ingredients, the shampoo includes: (A) 10-15% camellia seed extract by weight; (B) 2-3% ethylene glycol laurate by weight; (C) 0.15% cationic guar gum by weight; (D) 1-12% polyglycerol-10 and 0.05-1% polyglycerol ester by weight, wherein the weight ratio of polyglycerol-10 to polyglycerol-6 dioleate is 2-4:1; (E) 1.5-3% sodium citrate by weight; and (F) 40-60% deionized water by weight. However, this existing technology cannot inhibit the excessive reproduction of harmful microorganisms (such as fungi and bacteria), which can easily lead to problems such as increased dandruff and itchy scalp, and cannot guarantee scalp health. Summary of the Invention

[0004] The purpose of this invention is to provide an antibacterial shampoo and its preparation method to solve the problems existing in the prior art.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution: An antibacterial shampoo is prepared from deionized water, disodium ethylenediaminetetraacetate, polyquaternium-10, sodium lauryl ether sulfate aqueous solution, cocamidopropyl betaine aqueous solution, antibacterial agent, dimethyl silicone oil, phenoxyethanol, sodium chloride, fragrance, and citric acid aqueous solution. The antibacterial agent is obtained by spray drying a mixture of aminated graphene quantum dots, quaternized chitosan powder, modified lithium saponite powder, and deionized water. The modified lithium saponite powder is prepared from lithium saponite powder, deionized water, and hexadecyltrimethylammonium bromide ethanol solution. The quaternized chitosan powder is prepared from chitosan powder, acetic acid aqueous solution, 2,3-epoxypropyltrimethylammonium chloride aqueous solution, and sodium hydroxide aqueous solution. The aminated graphene quantum dots are prepared from L-histidine, citric acid monohydrate, and deionized water.

[0006] Furthermore, the degree of deacetylation of the chitosan powder is 85-95%, and the number average molecular weight is 100,000-500,000 Da.

[0007] Furthermore, the mass fraction of the aqueous solution of 2,3-epoxypropyltrimethylammonium chloride is 40-50%.

[0008] Furthermore, the mass fraction of the hexadecyltrimethylammonium bromide ethanol solution is 1-3%.

[0009] A method for preparing an antibacterial shampoo includes the following steps: (1) Add L-histidine, citric acid monohydrate and deionized water to a closed pressure-resistant closed reaction vessel, stir at 300-500 rpm for 20-40 minutes at 25-35℃, then stir at 180-200℃ for 6-8 hours, cool to 25±5℃, centrifuge at 8000-10000 rpm for 20-30 minutes, take the supernatant and freeze dry at -40℃ to -50℃ and vacuum degree below 100Pa for 24-48 hours to obtain amino-based graphene quantum dots; (2) Mix chitosan powder with acetic acid aqueous solution of 1-2% by mass, stir at 400-600 rpm for 2-3 hours at 40-50℃, then add 2,3-epoxypropyltrimethylammonium chloride aqueous solution, adjust the pH value to 8.5-9.0 with sodium hydroxide aqueous solution of 9-11% by mass, and then continue stirring at 70-80℃ for 6-8 hours. Then pour the mixture into 5 times its mass of ethanol aqueous solution of 70-80% by mass to precipitate, filter, wash the precipitate 2-4 times with ethanol aqueous solution of 70-80% by mass, vacuum dry at 45-55℃ for 2-4 hours, grind through 100-200 mesh sieve to obtain quaternized chitosan powder; (3) Lithium saponite powder with a particle size of 20-50 nm is slowly added to deionized water over 20-30 minutes. The mixture is stirred at 800-1000 rpm at 50-60°C for 30-40 minutes. Then, hexadecyltrimethylammonium bromide ethanol solution is slowly added dropwise over 30-60 minutes at 50-60°C and 300-400 rpm. After the addition is complete, the mixture is stirred for 2-3 hours. Then, the mixture is centrifuged at 8000-10000 rpm at 4-10°C for 20-30 minutes. The precipitate is collected and washed with deionized water and ethanol alternately 2-4 times. The mixture is then vacuum dried at 50-60°C for 2-4 hours and ground through a 100-200 mesh sieve to obtain modified lithium saponite powder. (4) Mix the aminated graphene quantum dots, quaternized chitosan powder, modified lithium saponite powder and deionized water, and ultrasonically disperse them at a power of 300-400W for 15-25 minutes. Stir them at a speed of 5000-7000rpm at 50-60℃ for 30-40 minutes. Then spray dry the mixture. The inlet temperature of the spray dryer is 140-150℃ and the outlet temperature is 70-90℃ to obtain the antibacterial agent. (5) Add deionized water and disodium ethylenediaminetetraacetate to a sealed reactor, stir at 50-100 rpm for 20-30 minutes at 75-80℃, cool to 30-35℃, then add polyquaternium-10, a 60-70% sodium lauryl ether sulfate aqueous solution, and a 20-30% cocamidopropyl betaine aqueous solution in sequence, and continue stirring for 20-30 minutes. Then add the antibacterial agent and dimethyl silicone oil in sequence. Stir at 8000-10000 rpm for 10-20 minutes, then add phenoxyethanol, sodium chloride and fragrance, and stir at 200-300 rpm for 30-40 minutes. Adjust the pH value to 5.5-6.0 with a 9-11% citric acid aqueous solution. Finally, degas under a vacuum of -0.05MPa to -0.06MPa and a stirring speed of 30-50 rpm for 15-20 minutes, and discharge to obtain antibacterial shampoo.

[0010] Furthermore, in step (1), the mass ratio of L-histidine, citric acid monohydrate, and deionized water is 1-2:3-4:40-60.

[0011] Furthermore, in step (2), the mass ratio of chitosan powder, acetic acid aqueous solution and 2,3-epoxypropyltrimethylammonium chloride aqueous solution is 5:80-100:10-15.

[0012] Furthermore, in step (3), the mass ratio of lithium saponite powder, deionized water and hexadecyltrimethylammonium bromide ethanol solution is 2:90-110:15-20.

[0013] Furthermore, in step (4), the mass ratio of aminated graphene quantum dots, quaternized chitosan powder, modified lithium saponite powder and deionized water is 0.5-1:1-2:0.05-0.2:20-30.

[0014] Furthermore, in step (5), the mass ratio of deionized water, disodium EDTA, polyquaternium-10, sodium lauryl ether sulfate aqueous solution, cocamidopropyl betaine aqueous solution, antibacterial agent, dimethyl silicone oil, phenoxyethanol, sodium chloride and fragrance is 650-750:0.5-1.5:0.5-2:120-180:30-70:1-3:10-30:3-7:5-15:0.5-2.

[0015] Compared with the prior art, the beneficial effects achieved by the present invention are: 1. In this invention, L-histidine and citric acid monohydrate are synthesized into aminated graphene quantum dots via a hydrothermal reaction. During this process, citric acid provides a carbon source and is carbonized under high temperature and pressure to form a graphene quantum dot framework. The nitrogen-containing heterocycle and amino group of L-histidine are incorporated into this framework through a reaction, endowing it with abundant amino functional groups on its surface. The amino group of chitosan undergoes a ring-opening reaction with the epoxy group in the 2,3-epoxypropyltrimethylammonium chloride molecule, thereby covalently grafting the quaternary ammonium salt cationic group onto the chitosan molecular chain to obtain quaternized chitosan. The cationic surfactant hexadecyltrimethylammonium bromide modifies lithium saponite through ion exchange and adsorption. The cationic properties of quaternized chitosan and modified lithium saponite in the antibacterial agent adsorb onto the negatively charged microbial cell membrane surface through electrostatic adsorption. The cationic groups of quaternized chitosan cause leakage of cell contents by disrupting the charge balance and permeability of the cell membrane lipid bilayer. The edges of the aminated graphene quantum dots can disrupt the microbial cell membrane structure. Detailed Implementation

[0016] The following embodiments are provided to better understand the present invention and are not limited to the preferred embodiments described. They do not constitute a limitation on the content and scope of protection of the present invention. Any product that is the same as or similar to the present invention, derived by any person under the guidance of the present invention or by combining the features of the present invention with other prior art, falls within the protection scope of the present invention.

[0017] An antibacterial shampoo is prepared from deionized water, disodium ethylenediaminetetraacetate, polyquaternium-10, sodium lauryl ether sulfate aqueous solution, cocamidopropyl betaine aqueous solution, antibacterial agent, dimethyl silicone oil, phenoxyethanol, sodium chloride, fragrance, and citric acid aqueous solution. The antibacterial agent is obtained by spray drying a mixture of aminated graphene quantum dots, quaternized chitosan powder, modified lithium saponite powder, and deionized water. The modified lithium saponite powder is prepared from lithium saponite powder, deionized water, and hexadecyltrimethylammonium bromide ethanol solution. The quaternized chitosan powder is prepared from chitosan powder, acetic acid aqueous solution, 2,3-epoxypropyltrimethylammonium chloride aqueous solution, and sodium hydroxide aqueous solution. The aminated graphene quantum dots are prepared from L-histidine, citric acid monohydrate, and deionized water.

[0018] For experiments not specifically described in the examples, the procedures or conditions should be followed according to the conventional experimental procedures described in the literature in this field. Reagents or instruments whose manufacturers are not specified are all commercially available conventional reagent products.

[0019] Example 1

[0020] (1) L-histidine, citric acid monohydrate and deionized water were added to a closed pressure-resistant closed reaction vessel and stirred at 300 rpm for 20 minutes at 25°C. Then, the mixture was stirred at 180°C for 6 hours. After cooling to 25±5°C, the mixture was centrifuged at 8000 rpm for 20 minutes. The supernatant was then freeze-dried at -40°C and a vacuum of less than 100 Pa for 24 hours to obtain amino-based graphene quantum dots. The mass ratio of L-histidine, citric acid monohydrate and deionized water was 1:3:40.

[0021] (2) Chitosan powder and acetic acid aqueous solution with a mass fraction of 1% were mixed and stirred at 400 rpm for 2 hours at 40°C. Then, 2,3-epoxypropyltrimethylammonium chloride aqueous solution with a mass fraction of 40% was added. The pH value was adjusted to 8.5 with sodium hydroxide aqueous solution with a mass fraction of 9% and stirred at 70°C for 6 hours. The mixture was then poured into 5 times its mass of 70% ethanol aqueous solution to precipitate. The mixture was filtered and washed twice with 70% ethanol aqueous solution. The precipitate was dried under vacuum at 45°C for 2 hours and ground through a 100-mesh sieve to obtain quaternized chitosan powder. The degree of deacetylation of the chitosan powder was 85% and the number average molecular weight was 100,000 Da. The mass ratio of chitosan powder, acetic acid aqueous solution and 2,3-epoxypropyltrimethylammonium chloride aqueous solution was 5:80:10.

[0022] (3) Lithium saponite powder with a particle size of 20 nm was slowly added to deionized water over 20 minutes. The mixture was stirred at 800 rpm at 50 °C for 30 minutes. Then, a 1% hexadecyltrimethylammonium bromide ethanol solution was slowly added dropwise over 30 minutes at 50 °C and a stirring speed of 300 rpm. After the addition was complete, the mixture was stirred for 2 hours. The mixture was then centrifuged at 8000 rpm at 4 °C for 20 minutes. The precipitate was collected and washed twice with deionized water and ethanol alternately. The mixture was then vacuum dried at 50 °C for 2 hours and ground through a 100-mesh sieve to obtain modified lithium saponite powder. The mass ratio of lithium saponite powder, deionized water and hexadecyltrimethylammonium bromide ethanol solution was 2:90:15.

[0023] (4) Mix the aminated graphene quantum dots, quaternized chitosan powder, modified lithium saponite powder and deionized water, and ultrasonically disperse them at 300W for 15 minutes. Stir them at 5000rpm for 30 minutes at 50℃. Then spray dry the mixture. The inlet temperature of the spray dryer is 140℃ and the outlet temperature is 70℃ to obtain the antibacterial agent. The mass ratio of aminated graphene quantum dots, quaternized chitosan powder, modified lithium saponite powder and deionized water is 0.5:1:0.05:20.

[0024] (5) Add deionized water and disodium ethylenediaminetetraacetate to a closed reaction vessel, stir at 50 rpm for 20 minutes at 75°C, cool down to 30°C, then add polyquaternium-10, 60% sodium lauryl ether sulfate aqueous solution and 20% cocamidopropyl betaine aqueous solution in sequence, and continue stirring for 20 minutes. Add antibacterial agent and dimethyl silicone oil in sequence, stir at 8000 rpm for 10 minutes, then add phenoxyethanol, sodium chloride and fragrance, stir at 200 rpm for 30 minutes, adjust the pH value to 5.5 with 9% citric acid aqueous solution, and finally degas for 15 minutes under a vacuum of -0.05 MPa and a stirring speed of 30 rpm, and discharge the material to obtain antibacterial shampoo. The mass ratio of deionized water, disodium EDTA, polyquaternium-10, sodium lauryl ether sulfate aqueous solution, cocamidopropyl betaine aqueous solution, antibacterial agent, dimethyl silicone oil, phenoxyethanol, sodium chloride and fragrance is 650:0.5:0.5:120:30:1:10:3:5:0.5.

[0025] Example 2

[0026] (1) L-histidine, citric acid monohydrate and deionized water were added to a closed pressure-resistant closed reaction vessel and stirred at 400 rpm for 30 minutes at 30°C. Then, the mixture was stirred at 190°C for 7 hours. After cooling to 25±5°C, the mixture was centrifuged at 9000 rpm for 25 minutes. The supernatant was then freeze-dried at -45°C and a vacuum of less than 100 Pa for 36 hours to obtain amino-based graphene quantum dots. The mass ratio of L-histidine, citric acid monohydrate and deionized water was 1.5:3.5:50.

[0027] (2) Chitosan powder and acetic acid aqueous solution with a mass fraction of 1.5% were mixed and stirred at 500 rpm for 2.5 hours at 45°C. Then, 2,3-epoxypropyltrimethylammonium chloride aqueous solution with a mass fraction of 45% was added. The pH value was adjusted to 8.7 with sodium hydroxide aqueous solution with a mass fraction of 10% and stirred at 75°C for 7 hours. The mixture was then poured into 5 times its mass of 75% ethanol aqueous solution to precipitate. The mixture was filtered and washed three times with 75% ethanol aqueous solution. The precipitate was dried under vacuum at 50°C for 3 hours and ground through a 150-mesh sieve to obtain quaternized chitosan powder. The degree of deacetylation of the chitosan powder was 90% and the number average molecular weight was 300,000 Da. The mass ratio of chitosan powder, acetic acid aqueous solution and 2,3-epoxypropyltrimethylammonium chloride aqueous solution was 5:90:12.5.

[0028] (3) Lithium saponite powder with a particle size of 35 nm was slowly added to deionized water over 25 minutes. The mixture was stirred at 900 rpm at 55 °C for 35 minutes. Then, a 2% hexadecyltrimethylammonium bromide ethanol solution was slowly added dropwise over 45 minutes at 55 °C and 350 rpm. After the addition was complete, the mixture was stirred for 2.5 hours. The mixture was then centrifuged at 9000 rpm at 6 °C for 25 minutes. The precipitate was collected and washed three times alternately with deionized water and ethanol. The mixture was then vacuum dried at 55 °C for 3 hours and ground through a 150-mesh sieve to obtain modified lithium saponite powder. The mass ratio of lithium saponite powder, deionized water, and hexadecyltrimethylammonium bromide ethanol solution was 2:100:17.

[0029] (4) Mix the aminated graphene quantum dots, quaternized chitosan powder, modified lithium saponite powder and deionized water, and ultrasonically disperse them at 350W for 20 minutes. Stir them at 6000rpm at 55℃ for 35 minutes. Then spray dry the mixture. The inlet temperature of the spray dryer is 145℃ and the outlet temperature is 80℃ to obtain the antibacterial agent. The mass ratio of aminated graphene quantum dots, quaternized chitosan powder, modified lithium saponite powder and deionized water is 0.75:1.5:0.125:25.

[0030] (5) Add deionized water and disodium ethylenediaminetetraacetate to a closed reaction vessel, stir at 75 rpm for 25 minutes at 77.5℃, cool down to 32.5℃, then add polyquaternium-10, 65% sodium lauryl ether sulfate aqueous solution and 25% cocamidopropyl betaine aqueous solution in sequence, and continue stirring for 25 minutes. Add antibacterial agent and dimethyl silicone oil in sequence, stir at 9000 rpm for 15 minutes, then add phenoxyethanol, sodium chloride and fragrance, stir at 250 rpm for 35 minutes, adjust the pH value to 5.7 with 10% citric acid aqueous solution, and finally degas at -0.055 MPa vacuum and 40 rpm stirring speed for 17.5 minutes, and discharge to obtain antibacterial shampoo. The mass ratio of deionized water, disodium EDTA, polyquaternium-10, sodium lauryl ether sulfate aqueous solution, cocamidopropyl betaine aqueous solution, antibacterial agent, dimethyl silicone oil, phenoxyethanol, sodium chloride and fragrance is 700:1:1.25:150:50:2:20:5:10:1.25.

[0031] Example 3

[0032] (1) L-histidine, citric acid monohydrate and deionized water were added to a closed pressure-resistant closed reaction vessel and stirred at 500 rpm for 40 minutes at 35°C. Then, the mixture was stirred at 200°C for 8 hours. After cooling to 25±5°C, the mixture was centrifuged at 10000 rpm for 30 minutes. The supernatant was then freeze-dried at -50°C and a vacuum of less than 100 Pa for 48 hours to obtain amino-based graphene quantum dots. The mass ratio of L-histidine, citric acid monohydrate and deionized water was 2:4:60.

[0033] (2) Chitosan powder and acetic acid aqueous solution with a mass fraction of 2% were mixed and stirred at 600 rpm for 3 hours at 50°C. Then, 2,3-epoxypropyltrimethylammonium chloride aqueous solution with a mass fraction of 50% was added. The pH value was adjusted to 9.0 with sodium hydroxide aqueous solution with a mass fraction of 11% and stirred at 80°C for 8 hours. The mixture was then poured into 5 times its mass of 80% ethanol aqueous solution to precipitate. The mixture was filtered and washed 4 times with 80% ethanol aqueous solution. The mixture was then vacuum dried at 55°C for 4 hours and ground through a 200-mesh sieve to obtain quaternized chitosan powder. The degree of deacetylation of the chitosan powder was 95% and the number average molecular weight was 500,000 Da. The mass ratio of chitosan powder, acetic acid aqueous solution and 2,3-epoxypropyltrimethylammonium chloride aqueous solution was 5:100:15.

[0034] (3) Lithium saponite powder with a particle size of 50 nm was slowly added to deionized water over 30 minutes. The mixture was stirred at 1000 rpm at 60 °C for 40 minutes. Then, a 3% hexadecyltrimethylammonium bromide ethanol solution was slowly added dropwise over 60 minutes at 60 °C and 400 rpm. After the addition was complete, the mixture was stirred for 3 hours. The mixture was then centrifuged at 10000 rpm at 10 °C for 30 minutes. The precipitate was collected and washed 4 times alternately with deionized water and ethanol. The mixture was then vacuum dried at 60 °C for 4 hours and ground through a 200-mesh sieve to obtain modified lithium saponite powder. The mass ratio of lithium saponite powder, deionized water and hexadecyltrimethylammonium bromide ethanol solution was 2:110:20.

[0035] (4) Mix the aminated graphene quantum dots, quaternized chitosan powder, modified lithium saponite powder and deionized water, and ultrasonically disperse them at 400W for 25 minutes. Stir them at 7000rpm at 60℃ for 40 minutes. Then spray dry the mixture. The inlet temperature of the spray dryer is 150℃ and the outlet temperature is 90℃ to obtain the antibacterial agent. The mass ratio of aminated graphene quantum dots, quaternized chitosan powder, modified lithium saponite powder and deionized water is 1:2:0.2:30.

[0036] (5) Add deionized water and disodium ethylenediaminetetraacetate to a closed reaction vessel, stir at 100 rpm for 30 minutes at 80°C, cool down to 35°C, then add polyquaternium-10, 70% sodium lauryl ether sulfate aqueous solution and 30% cocamidopropyl betaine aqueous solution in sequence, and continue stirring for 30 minutes. Add antibacterial agent and dimethyl silicone oil in sequence, stir at 10000 rpm for 20 minutes, then add phenoxyethanol, sodium chloride and fragrance, stir at 300 rpm for 40 minutes, adjust the pH value to 6.0 with 11% citric acid aqueous solution, and finally degas for 20 minutes under a vacuum of -0.06 MPa and a stirring speed of 50 rpm, and discharge the material to obtain antibacterial shampoo. The mass ratio of deionized water, disodium ethylenediaminetetraacetate, polyquaternium-10, sodium lauryl ether sulfate aqueous solution, cocamidopropyl betaine aqueous solution, antibacterial agent, dimethyl silicone oil, phenoxyethanol, sodium chloride and fragrance is 750:1.5:2:180:70:3:30:7:15:2.

[0037] Comparative Example 1 The only difference between Comparative Example 1 and Example 1 is that no antibacterial agent was added.

[0038] Comparative Example 2 The only difference between Comparative Example 2 and Example 1 is that it does not contain amino-based graphene quantum dots.

[0039] Comparative Example 3 The only difference between Comparative Example 3 and Example 1 is that modified lithium saponite powder is not added.

[0040] Comparative Example 4 The only difference between Comparative Example 4 and Example 1 is that 2,3-epoxypropyltrimethylammonium chloride aqueous solution was not added, and the pH adjustment step was skipped.

[0041] The antibacterial performance test was conducted in accordance with QB / T2738-2023 "Evaluation Method for Antibacterial and Antimicrobial Effects of Daily Chemical Products". The shampoo sample was diluted 100 times with deionized water as the test solution. Table 1 below shows the performance analysis results of the embodiments and comparative examples of the present invention.

[0042] Table 1

[0043] Experimental data from the examples and comparative examples show that the edges of the amino-based graphene quantum dots of the present invention can disrupt the structure of microbial cell membranes; the quaternary ammonium salt cationic groups of quaternized chitosan are adsorbed onto the negatively charged surface of microbial cells through electrostatic interaction, thereby disrupting cell membrane permeability; the layered structure of the modified lithium saponite powder provides support for the system to prevent particle aggregation and enhance the stability of the shampoo.

[0044] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No markings in the claims should be construed as limiting the scope of the claims.

Claims

1. An antibacterial shampoo, characterized in that, The antibacterial shampoo is prepared from deionized water, disodium ethylenediaminetetraacetate, polyquaternium-10, sodium lauryl ether sulfate aqueous solution, cocamidopropyl betaine aqueous solution, antibacterial agent, dimethyl silicone oil, phenoxyethanol, sodium chloride, fragrance, and citric acid aqueous solution. The antibacterial agent is obtained by spray drying after mixing amino-based graphene quantum dots, quaternized chitosan powder, modified lithium saponite powder, and deionized water. The modified lithium saponite powder is prepared from lithium saponite powder, deionized water, and hexadecyltrimethylammonium bromide ethanol solution. The quaternized chitosan powder is prepared from chitosan powder, acetic acid aqueous solution, 2,3-epoxypropyltrimethylammonium chloride aqueous solution, and sodium hydroxide aqueous solution. The amino-based graphene quantum dots are prepared from L-histidine, citric acid monohydrate, and deionized water.

2. The antibacterial shampoo according to claim 1, characterized in that: The degree of deacetylation of chitosan powder is 85-95%, and the number average molecular weight is 100,000-500,000 Da.

3. The antibacterial shampoo according to claim 1, characterized in that: The mass fraction of the aqueous solution of 2,3-epoxypropyltrimethylammonium chloride is 40-50%.

4. The antibacterial shampoo according to claim 1, characterized in that: The mass fraction of the hexadecyltrimethylammonium bromide ethanol solution is 1-3%.

5. A method for preparing an antibacterial shampoo, applied to the antibacterial shampoo according to any one of claims 1-4, characterized in that, Includes the following steps: (1) Add L-histidine, citric acid monohydrate and deionized water to a closed pressure-resistant closed reaction vessel, stir at 300-500 rpm for 20-40 minutes at 25-35℃, then stir at 180-200℃ for 6-8 hours, cool to 25±5℃, centrifuge at 8000-10000 rpm for 20-30 minutes, take the supernatant and freeze dry at -40℃ to -50℃ and vacuum degree below 100Pa for 24-48 hours to obtain amino-based graphene quantum dots; (2) Mix chitosan powder with acetic acid aqueous solution of 1-2% by mass, stir at 400-600 rpm for 2-3 hours at 40-50℃, then add 2,3-epoxypropyltrimethylammonium chloride aqueous solution, adjust the pH value to 8.5-9.0 with sodium hydroxide aqueous solution of 9-11% by mass, and then continue stirring at 70-80℃ for 6-8 hours. Then pour the mixture into 5 times its mass of ethanol aqueous solution of 70-80% by mass to precipitate, filter, wash the precipitate 2-4 times with ethanol aqueous solution of 70-80% by mass, vacuum dry at 45-55℃ for 2-4 hours, grind through 100-200 mesh sieve to obtain quaternized chitosan powder; (3) Lithium saponite powder with a particle size of 20-50 nm is slowly added to deionized water over 20-30 minutes. The mixture is stirred at 800-1000 rpm at 50-60°C for 30-40 minutes. Then, hexadecyltrimethylammonium bromide ethanol solution is slowly added dropwise over 30-60 minutes at 50-60°C and 300-400 rpm. After the addition is complete, the mixture is stirred for 2-3 hours. Then, the mixture is centrifuged at 8000-10000 rpm at 4-10°C for 20-30 minutes. The precipitate is collected and washed with deionized water and ethanol alternately 2-4 times. The mixture is then vacuum dried at 50-60°C for 2-4 hours and ground through a 100-200 mesh sieve to obtain modified lithium saponite powder. (4) Mix the aminated graphene quantum dots, quaternized chitosan powder, modified lithium saponite powder and deionized water, and ultrasonically disperse them at a power of 300-400W for 15-25 minutes. Stir them at a speed of 5000-7000rpm at 50-60℃ for 30-40 minutes. Then spray dry the mixture. The inlet temperature of the spray dryer is 140-150℃ and the outlet temperature is 70-90℃ to obtain the antibacterial agent. (5) Add deionized water and disodium ethylenediaminetetraacetate to a sealed reactor, stir at 50-100 rpm for 20-30 minutes at 75-80℃, cool to 30-35℃, then add polyquaternium-10, a 60-70% sodium lauryl ether sulfate aqueous solution, and a 20-30% cocamidopropyl betaine aqueous solution in sequence, and continue stirring for 20-30 minutes. Then add the antibacterial agent and dimethyl silicone oil in sequence. Stir at 8000-10000 rpm for 10-20 minutes, then add phenoxyethanol, sodium chloride and fragrance, and stir at 200-300 rpm for 30-40 minutes. Adjust the pH value to 5.5-6.0 with a 9-11% citric acid aqueous solution. Finally, degas under a vacuum of -0.05MPa to -0.06MPa and a stirring speed of 30-50 rpm for 15-20 minutes, and discharge to obtain antibacterial shampoo.

6. The method for preparing an antibacterial shampoo according to claim 5, characterized in that: In step (1), the mass ratio of L-histidine, citric acid monohydrate and deionized water is 1-2:3-4:40-60.

7. The method for preparing an antibacterial shampoo according to claim 5, characterized in that: In step (2), the mass ratio of chitosan powder, acetic acid aqueous solution and 2,3-epoxypropyltrimethylammonium chloride aqueous solution is 5:80-100:10-15.

8. The method for preparing an antibacterial shampoo according to claim 5, characterized in that: In step (3), the mass ratio of lithium saponite powder, deionized water and hexadecyltrimethylammonium bromide ethanol solution is 2:90-110:15-20.

9. The method for preparing an antibacterial shampoo according to claim 5, characterized in that: In step (4), the mass ratio of aminated graphene quantum dots, quaternized chitosan powder, modified lithium saponite powder and deionized water is 0.5-1:1-2:0.05-0.2:20-30.

10. The method for preparing an antibacterial shampoo according to claim 5, characterized in that: In step (5), the mass ratio of deionized water, disodium ethylenediaminetetraacetate, polyquaternium-10, sodium lauryl ether sulfate aqueous solution, cocamidopropyl betaine aqueous solution, antibacterial agent, dimethyl silicone oil, phenoxyethanol, sodium chloride and fragrance is 650-750:0.5-1.5:0.5-2:120-180:30-70:1-3:10-30:3-7:5-15:0.5-2.

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