Antibacterial skin-care cleansing lotion and preparation method thereof

Abstract

The invention discloses an antibacterial skin-care cleansing lotion and a preparation method thereof, and belongs to the technical field of personal care products. The skin cleansing liquid comprises the following core components: a double-embedded tea tree oil microcapsule, wherein the inner layer of the double-embedded tea tree oil microcapsule comprises beta-cyclodextrin inclusion tea tree oil, the outer layer of the double-embedded tea tree oil microcapsule comprises a sodium alginate-chitosan ionic cross-linked membrane, natural antibacterial peptide PA-3, dipotassium glycyrrhizinate, sodium lauroyl sarcosinate, a hyaluronic acid cross-linked polymer and a pH buffer system. The preparation method comprises the following steps: constructing a dual-embedding microcapsule through spray drying-ionic crosslinking to realize slow release of the tea tree oil; the hyaluronic acid three-dimensional network is used for loading PA-3, and protease degradation is resisted; and uniform dispersion of the microcapsules is ensured by adopting biaxial shearing emulsification. The product has the advantages of efficient antibiosis, gradient controlled release, low irritation and thermal stability, and is suitable for daily skin care and cleaning and repairing of sensitive and damaged skin.

Description

Technical Field

[0001] The invention belongs to the technical field of personal care products and discloses an antibacterial soothing cleansing liquid and a preparation method thereof. Background Art

[0002] In the field of antibacterial soothing cleansing liquid, although related products have been widely used in recent years as people's demand for skin health and care has increased, the existing technology still has many shortcomings. Traditional chemical antibacterial agents such as triclosan, although they have significant antibacterial effects, are prone to skin irritation and allergic reactions when used for a long time, and may also increase bacterial resistance, reducing their effectiveness in long-term use. In addition, although single natural antibacterial ingredients such as tea tree oil have natural antibacterial properties, they are difficult to achieve long-term antibacterial effects in products due to their strong volatility and poor stability. Although ordinary moisturizing ingredients can relieve dry skin, they lack the function of promoting wound repair and accelerating epidermal regeneration, and cannot meet the repair needs of damaged skin such as postoperative or acne. Cationic conditioning agents such as polyquaternium salts, although they can provide certain conditioning effects, have a high residual amount, which can easily lead to pore blockage, increase the burden on the skin, and cause more skin problems.

[0003] In view of the above problems, the present invention proposes a novel antibacterial soothing cleansing liquid and a preparation method thereof, aiming to overcome the deficiencies of the prior art and provide a cleansing liquid with slow-release antibacterial, barrier repair and low residue characteristics. The present invention adopts a double embedding technology to encapsulate tea tree oil with the inner layer of β-cyclodextrin, and then uses a sodium alginate-chitosan ion cross-linked composite film as the outer layer, which significantly improves the stability and bioavailability of tea tree oil, and at the same time achieves a long-lasting slow-release antibacterial effect. In addition, the present invention introduces a natural antimicrobial peptide PA-3, which can target and destroy bacterial biofilms, synergize with tea tree oil, and significantly improve the antibacterial efficacy, especially the inhibition rate of common pathogens such as Propionibacterium acnes can reach 99.99%. In terms of soothing and repairing, dipotassium glycyrrhizinate and hyaluronic acid cross-linked polymers are added to the cleansing liquid, which not only provides anti-inflammatory and soothing effects, but also promotes the deep moisturizing and repair functions of the skin and accelerates epidermal regeneration. At the same time, the present invention adopts a low-irritation surfactant system and a non-allergenic preservative design to ensure the safety of the product in human patch tests, with a negative rate of up to 100%.

[0004] In summary, the present invention effectively solves the problems of antibacterial ingredient irritation, insufficient stability, limited moisturizing and repairing function, and conditioner residues in the prior art through scientific formula design and process optimization, and provides an efficient, gentle and safe care solution for postoperative or acne skin, demonstrating significant technical advantages and innovation. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides an antibacterial soothing cleansing liquid, comprising the following components in percentage by mass:

[0006] Double-encapsulated tea tree oil microcapsules: 1% to 3%, consisting of an inner layer of β-cyclodextrin encapsulated tea tree oil and an outer layer of sodium alginate-chitosan ion cross-linked composite membrane, wherein the mass ratio of tea tree oil to β-cyclodextrin is 1:3 to 5, and the mass ratio of sodium alginate to chitosan is 2 to 3:1;

[0007] Natural antimicrobial peptide PA-3: 0.1%~0.5%, derived from American cockroach extract, with a molecular weight of 1.2kDa~1.8kDa;

[0008] Dipotassium glycyrrhizinate: 2% to 4%;

[0009] Sodium lauroyl sarcosinate: 3% to 5%;

[0010] Hyaluronic acid cross-linked polymer: 0.5% to 1%, molecular weight of 800 kDa to 1.2 MDa, cross-linking degree of 10% to 15%;

[0011] pH buffer: composed of citric acid and sodium citrate, adjusting the system pH to 5.0-5.5;

[0012] Deionized water: balance.

[0013] Furthermore, under the condition of pH 5.0-5.5, the cumulative release rate of tea tree oil in the double-embedded tea tree oil microcapsules is 40%-50% and the cumulative release rate of PA-3 is 55%-65% within 24 hours.

[0014] Furthermore, the natural antimicrobial peptide PA-3 is prepared by the following steps:

[0015] a. After the American cockroach body is crushed, ultrasonic-assisted extraction is performed using a phosphate buffer solution of pH 7.4, and the supernatant is collected after centrifugation;

[0016] b. Separating low molecular weight components by ultrafiltration membrane;

[0017] c. Purify by cation exchange chromatography and reverse phase high performance liquid chromatography to obtain PA-3 with a purity of ≥95%.

[0018] Furthermore, the hyaluronic acid cross-linked polymer is sodium hyaluronate cross-linked with 1,4-butanediol diglycidyl ether, and its three-dimensional network pore size is 50nm to 100nm, which is used to load and protect PA-3 from protease degradation.

[0019] A method for preparing an antibacterial soothing cleansing liquid comprises the following steps:

[0020] Step 1: Preparation of double-encapsulated tea tree oil microcapsules

[0021] a. Mix tea tree oil and β-cyclodextrin in a mass ratio of 1:3 to 1:5, stir in a water bath at 50°C for 2 hours, and spray dry to obtain a primary inclusion complex;

[0022] b. dispersing the primary inclusion compound in a 2% sodium alginate solution to form a 5% suspension;

[0023] c. adding 1% chitosan acetate solution by mass, the mass ratio of sodium alginate to chitosan is 2-3:1, reacting at 500 rpm with magnetic stirring for 30 minutes, curing by calcium ion cross-linking, and spray drying again to obtain double-embedded microcapsules;

[0024] Step 2: Preparation of PA-3-hyaluronic acid complex

[0025] d. PA-3 and hyaluronic acid cross-linked polymer were mixed at a mass ratio of 1:10 and allowed to stand at 4°C for 12 hours to form a loaded complex;

[0026] Step 3: Gradient controlled release mixing

[0027] e. Add sodium lauroyl sarcosinate to deionized water at 45°C and stir until completely dissolved to form a surfactant base solution;

[0028] f. Add the double-embedded microcapsules to the active base liquid and homogenize and emulsify using a biaxial shear emulsifier for 15 minutes;

[0029] g. The system was cooled to 38 ° C, PA-3-hyaluronic acid complex and dipotassium glycyrrhizinate were added sequentially, and stirred for 20 minutes;

[0030] h. Adjust the pH to 5.0-5.5 with citric acid-sodium citrate buffer, filter and then fill.

[0031] Furthermore, the shear rate of the biaxial shear emulsifier is 10000 s-1 to 12000 s-1, and the shear time is 10 to 15 minutes, so that the microcapsules are evenly dispersed in the system without aggregation.

[0032] Furthermore, the product also includes auxiliary ingredients, and in step three, one or more of the auxiliary ingredients salicylic acid microspheres 0.5% to 2%, Centella asiatica extract 0.1% to 0.5% or panthenol 0.3% to 1% may be added.

[0033] The antibacterial soothing cleansing liquid and its preparation method of the present invention, through scientific formula design and process optimization, realizes the organic combination of the triple effects of efficient antibacterial, soothing repair and low irritation, and embodies significant technical advantages and innovation. In terms of antibacterial performance, this method makes full use of the synergistic effect of double-embedded tea tree oil microcapsules and natural antibacterial peptide PA-3. As a natural antibacterial ingredient, tea tree oil itself has the ability to inhibit the growth of a variety of bacteria, and PA-3 further enhances this effect, especially for common pathogens such as Propionibacterium acnes. The inhibition rate can reach 99.99%, which is significantly better than traditional methods. The realization of this efficient antibacterial effect is attributed to the ability of PA-3 to accurately destroy bacterial biofilms, while tea tree oil plays an auxiliary role by virtue of its natural antibacterial properties. The synergistic effect of the two significantly improves the antibacterial performance of the cleansing liquid.

[0034] In terms of soothing and repairing functions, dipotassium glycyrrhizinate and hyaluronic acid cross-linked polymers are specially added to the cleanser. Dipotassium glycyrrhizinate can effectively relieve skin discomfort with its anti-inflammatory and soothing properties, while hyaluronic acid cross-linked polymers provide deep moisturizing and repairing functions for the skin. This combination of ingredients can not only relieve dry skin and itching, but also promote skin self-repair, keeping the skin hydrated and healthy after cleansing.

[0035] In terms of low irritation, the preparation method strictly selects a low irritation surfactant system and a non-allergenic preservative design. In the human patch test, the cleansing liquid showed extremely high safety, with a negative rate of up to 100%. Compared with the cationic conditioning agents (such as polyquaternium salts) used in traditional methods, the present invention effectively avoids irritation problems by optimizing the formula and process.

[0036] From the perspective of synthesis mechanism, the design of double-encapsulated tea tree oil microcapsules is crucial. The inner layer of β-cyclodextrin can effectively encapsulate tea tree oil, improving its stability and bioavailability; the outer layer of sodium alginate-chitosan ion cross-linked composite membrane further enhances the stability of the microcapsules, allowing them to maintain a high tea tree oil retention rate under high temperature and long-term storage conditions. This double-layer encapsulation structure not only improves the stability of tea tree oil, but also achieves a sustained release effect under suitable pH conditions, further improving the antibacterial efficacy of the product.

[0037] In summary, the method for preparing the antibacterial soothing cleansing liquid of the present invention has built multiple technical barriers in terms of antibacterial efficacy, soothing and repairing function, and product safety through ingredient synergy and process optimization, providing consumers with an efficient, gentle and safe skin care option. DETAILED DESCRIPTION

[0038] 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 combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0039] The following is a detailed description of an antibacterial skin cleansing liquid and a preparation method thereof provided by the present invention through examples.

[0040] Embodiment 1:

[0041] Formula (mass percentage):

[0042] Double-encapsulated tea tree oil microcapsules: 2%;

[0043] Natural antimicrobial peptide PA-3: 0.3%;

[0044] Dipotassium glycyrrhizinate: 3%;

[0045] Sodium lauroyl sarcosinate: 4%;

[0046] Hyaluronic acid cross-linked polymer is sodium hyaluronate cross-linked with 1,4-butanediol diglycidyl ether (cross-linking degree 12%, 1 MDa): 0.8%;

[0047] Phenoxyethanol: 0.5%;

[0048] Citric acid / sodium citrate buffer: adjust pH to 5.3 ± 0.1;

[0049] Deionized water: Make up to 100%.

[0050] Preparation method:

[0051] Step 1: Preparation of double-encapsulated tea tree oil microcapsules

[0052] (1) Primary inclusion:

[0053] Tea tree oil and β-cyclodextrin were mixed in a mass ratio of 1:4, placed in a 50°C constant temperature water bath, and stirred at 500 rpm for 2 hours. Spray drying (inlet air temperature 120°C, outlet air temperature 60°C) was performed to collect the primary inclusion complex.

[0054] (2) Double-layer coating:

[0055] The primary inclusion complex was dispersed in a 2% sodium alginate solution (mass concentration 5%) and homogenized by ultrasound (power 100 W, time 5 minutes).

[0056] 1% chitosan acetate solution (pH 4.5) was added dropwise to control the mass ratio of sodium alginate to chitosan to be 2.5:1, and stirred at 500 rpm for 30 minutes.

[0057] 0.5% CaCl2 solution was added for cross-linking and curing for 10 minutes, and then spray-dried for a second time to obtain double-embedded microcapsules.

[0058] Detection: Dynamic light scattering (DLS) showed that the microcapsule particle size was 200-500nm, the polydispersity index (PDI) was ≤0.2, and the Zeta potential was +25~+30mV.

[0059] Step 2: Preparation of PA-3-hyaluronic acid complex

[0060] (1) Extraction of natural antimicrobial peptide PA-3:

[0061] After the American cockroach body was crushed, pH 7.4 phosphate buffer (containing 0.1% Triton X-100) was added and ultrasonic extraction (frequency 40 kHz, time 30 minutes) was performed.

[0062] Centrifuge (8000×g, 15 minutes), take the supernatant, and separate the low molecular weight components through a 3 kDa ultrafiltration membrane. Cation exchange chromatography: SP Sepharose FF column, elute with 0-1 M NaCl gradient (flow rate 1 mL / min), and collect the active peak.

[0063] Reverse phase HPLC purification: C18 column, acetonitrile / water (containing 0.1% TFA) gradient elution to obtain PA-3 with a purity of ≥95%.

[0064] (2) Complex construction:

[0065] Sodium hyaluronate (1 MDa) was reacted with a cross-linking agent (cross-linking degree 12%) at pH 8.5 for 24 hours, dialyzed, and then freeze-dried.

[0066] PA-3 and cross-linked hyaluronic acid were mixed in a mass ratio of 1:10 and allowed to stand at 4°C for 12 hours to form a complex.

[0067] Step 3: Gradient controlled release mixing

[0068] (1) Preparation of surfactant base liquid:

[0069] Dissolve sodium lauroyl sarcosinate (4%) in 45°C deionized water and stir until completely transparent.

[0070] (2) Microcapsule emulsification: Add double-embedded microcapsules (2%) and homogenize for 12 minutes using a dual-axis shear emulsifier (main axis 5100 rpm, secondary axis 4900 rpm) at a shear rate of 11000 s-1.

[0071] (3) Addition of active ingredients:

[0072] The temperature was lowered to 38° C., and PA-3-hyaluronic acid complex (0.3%) and dipotassium glycyrrhizinate (3%) were added in sequence, and stirred for 20 minutes.

[0073] (4) pH adjustment and filling: an antibacterial skin cleansing liquid and its preparation method

[0074] The pH of the system was adjusted to 5.3±0.1 with citric acid / sodium citrate buffer, and phenoxyethanol (0.5%) was added. The solution was sterilized through a 0.22 μm filter membrane and aseptically filled.

[0075] Embodiment 2:

[0076] The formula was adjusted by adding salicylic acid microspheres (1%) and replacing part of the deionized water. The rest was the same as in Example 1.

[0077] Embodiment 3:

[0078] The formula was adjusted, the hyaluronic acid cross-linked polymer was increased to 1.2%, and PA-3 was reduced to 0.2%. The rest was the same as in Example 1.

[0079] Comparative Example 1:

[0080] Only β-cyclodextrin was used to encapsulate tea tree oil (without the outer layer of sodium alginate-chitosan), and the rest was the same as in Example 1.

[0081] Comparative Example 2:

[0082] The double-embedded microcapsules were replaced with polyquaternium-7 (1.5%), and the rest was the same as in Example 1.

[0083] Comparative Example 3:

[0084] PA-3 was omitted, and the rest was the same as in Example 1.

[0085] Performance Test:

[0086] Antibacterial rate test:

[0087] Standard: ISO 20743 (thin film method), inoculation volume 1×10 6 CFU / mL, incubated at 37°C for 24 h;

[0088] calculate:

[0089]

[0090] Human patch test negative rate test method:

[0091] Subject screening: healthy adults aged 18-60 years (without active skin diseases, immune diseases or allergies).

[0092] The skin at the test site is intact (no damage or inflammation) and there is no suspicious reaction: negative (sample size: more than 30 people).

[0093] Test material preparation:

[0094] Test substances: stock solutions of Examples and Comparative Examples.

[0095] Carrier selection: non-woven fabric.

[0096] Control settings: negative control, normal saline; positive control: 0.1% sodium dodecyl sulfate (SLS, used to verify the sensitivity of the test).

[0097] Application area: upper back or flexor side of forearm (avoid hair and scars).

[0098] Application method: Load the test substance and control substance onto the patch separately and apply for 48 hours (occlusive application).

[0099]

[0100] Cytotoxicity assay (MTT method):

[0101] Cell culture: Immortalized human keratinocytes (HaCaT) were used and cultured at 37°C and 5% CO2 until the logarithmic growth phase.

[0102] Sample treatment: The product was diluted to the working concentration (5%) and incubated with cells for 24 hours.

[0103] Survival rate determination: Add MTT reagent (0.5 mg / mL), incubate for 4 hours to dissolve the formazan crystals (DMSO), measure the absorbance at 570 nm, and calculate the cell survival rate:

[0104]

[0105] Tea tree oil retention rate (60℃ / 14 days) test:

[0106] The sample was sealed and placed in a 60°C thermostat for 14 days. Take 1 g of the sealed and stored sample, add 5 mL of n-hexane for vortex extraction, centrifuge (5000×g, 10 minutes), and take the supernatant to pass through a 0.22 μm filter membrane. Perform GC analysis (injection port temperature: 250°C; detector temperature: 280°C; column temperature program: 60°C→10°C / min→240°C (maintained for 5 minutes); carrier gas (N2): 1 mL / min; injection volume: 1 μL, split ratio 10:1) Retention rate calculation:

[0107]

[0108] The embodiments and comparative examples were tested repeatedly, and the specific test results are shown in Table 1.

[0109] Table 1 Performance test data of Examples 1 to 3 and Comparative Examples 1 to 3

[0110]

[0111] As shown in Table 1, Example 2 has an antibacterial rate of up to 99.99% against Propionibacterium acnes, while Comparative Example 2 has an antibacterial rate of only 30%. This is due to the synergistic effect of salicylic acid microspheres and PA-3 in Example 2. Salicylic acid can dissolve hair follicle plugs and inhibit sebum secretion, thereby reducing the environment for bacterial growth; at the same time, PA-3 can target and destroy bacterial biofilms, and the dual effects significantly improve the antibacterial effect. In terms of the antibacterial rate of Escherichia coli, Example 1 reached 98%, which is much higher than the 60% of Comparative Example 3. This advantage is due to the outer layer of chitosan (Zeta potential is +25 to +30mV) through electrostatic adsorption, which enhances the penetration and destruction ability of tea tree oil on the cell membrane of Gram-negative bacteria. In the tea tree oil retention rate test, the double-layer embedding structure (inner layer β-cyclodextrin, outer layer sodium alginate-chitosan ion cross-linked composite membrane) used in Example 1 retained tea tree oil at 60°C for 14 days, which was significantly higher than the 68% of the single-layer embedding structure of Comparative Example 1, proving that the outer ion cross-linked membrane can effectively block high-temperature oxidation and protect the stability of tea tree oil. In the human patch test, the negative rate of Examples 1 and 2 reached 100% due to the use of low-irritation surfactant systems and non-allergenic preservative formulas, while the negative rate of Comparative Example 2 was only 82% due to the increased irritation caused by the residual traditional cationic conditioning agents (such as polyquaternium salts). These data fully show that the present invention has built significant technical advantages in antibacterial efficacy, component stability and human safety through the synergistic effect of ingredients and optimized process design, forming multiple technical barriers.

Claims

1. An antibacterial soothing cleansing liquid, characterized in that: The following components are included in mass percentage: Double-encapsulated tea tree oil microcapsules: 1% to 3%, consisting of an inner layer of β-cyclodextrin encapsulated tea tree oil and an outer layer of sodium alginate-chitosan ion cross-linked composite membrane, wherein the mass ratio of tea tree oil to β-cyclodextrin is 1:3 to 5, and the mass ratio of sodium alginate to chitosan is 2 to 3:1; Natural antimicrobial peptide PA-3: 0.1%~0.5%, derived from American cockroach extract, with a molecular weight of 1.2kDa~1.8kDa; Dipotassium glycyrrhizinate: 2% to 4%; Sodium lauroyl sarcosinate: 3% to 5%; Hyaluronic acid cross-linked polymer: 0.5% to 1%, molecular weight of 800 kDa to 1.2 MDa, cross-linking degree of 10% to 15%; pH buffer: composed of citric acid and sodium citrate, adjusting the system pH to 5.0-5.5; Deionized water: balance.

2. The antibacterial skin cleansing liquid according to claim 1, characterized in that: Under the condition of pH 5.0-5.5, the cumulative release rate of the double-embedded tea tree oil microcapsules in 24 hours is 40%-50%, and the cumulative release rate of PA-3 is 55%-65%.

3. The antibacterial skin cleanser according to claim 1, characterized in that: The natural antimicrobial peptide PA-3 is prepared by the following steps: a. After the American cockroach body is crushed, ultrasonic-assisted extraction is performed using a phosphate buffer solution of pH 7.4, and the supernatant is collected after centrifugation; b. Separating low molecular weight components by ultrafiltration membrane; c. Purify by cation exchange chromatography and reverse phase high performance liquid chromatography to obtain PA-3 with a purity of ≥95%.

4. The antibacterial skin cleanser according to claim 1, characterized in that: The hyaluronic acid cross-linked polymer is sodium hyaluronate cross-linked with 1,4-butanediol diglycidyl ether, and its three-dimensional network pore size is 50nm-100nm, which is used to load and protect PA-3 from protease degradation.

5. A method for preparing the antibacterial soothing cleansing liquid according to any one of claims 1 to 4, characterized in that: The following steps are involved: Step 1: Preparation of double-encapsulated tea tree oil microcapsules a. Mix tea tree oil and β-cyclodextrin in a mass ratio of 1:3 to 1:5, stir in a water bath at 50°C for 2 hours, and spray dry to obtain a primary inclusion complex; b. dispersing the primary inclusion compound in a 2% sodium alginate solution to form a 5% suspension; c. adding 1% chitosan acetate solution by mass, the mass ratio of sodium alginate to chitosan is 2-3:1, reacting at 500 rpm with magnetic stirring for 30 minutes, curing by calcium ion cross-linking, and spray drying again to obtain double-embedded microcapsules; Step 2: Preparation of PA-3-hyaluronic acid complex d. PA-3 and hyaluronic acid cross-linked polymer were mixed at a mass ratio of 1:10 and allowed to stand at 4°C for 12 hours to form a loaded complex; Step 3: Gradient controlled release mixing e. Add sodium lauroyl sarcosinate to deionized water at 45°C and stir until completely dissolved to form a surfactant base solution; f. Add the double-embedded microcapsules to the active base liquid and homogenize and emulsify using a biaxial shear emulsifier for 15 minutes; g. The system was cooled to 38 ° C, PA-3-hyaluronic acid complex and dipotassium glycyrrhizinate were added sequentially, and stirred for 20 minutes; h. Adjust the pH to 5.0-5.5 with citric acid-sodium citrate buffer, filter and then fill.

6. The method for preparing an antibacterial soothing cleansing liquid according to claim 5, characterized in that: The shear rate of the biaxial shear emulsifier is 10000s -1 Up to 12000s -1 The shearing time is 10 to 15 minutes, so that the microcapsules are evenly dispersed in the system without aggregation.

7. The method for preparing an antibacterial soothing cleansing liquid according to claim 5, characterized in that: The product also includes auxiliary ingredients, and in step three, one or more of the auxiliary ingredients salicylic acid microspheres 0.5% to 2%, Centella asiatica extract 0.1% to 0.5% or panthenol 0.3% to 1% may be added.

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