Preparation method and application of sodium alginate hydrogel mask with high water content

Abstract

The invention provides a preparation method of a sodium alginate hydrogel mask with high water content, which comprises the following steps: smearing a solution A into a specific shape, then smearing a solution B onto the surface of the solution A with the specific shape, and carrying out cross-linking reaction on the solution A and the solution B to obtain the sodium alginate hydrogel mask with a self-defined shape, the solution A is a sodium alginate solution with the mass concentration range of 1%-7%; the solution B is a calcium ion solution with the concentration range of 100-400 mM, and comprises poloxamer, zinc hyaluronate and carbomer 941. The smooth and transparent wet mask can be rapidly obtained, the use shape and size of the mask are customized, and different whitening, anti-inflammatory and other components can be added according to the skin state. Besides, the mask has the moisturizing rate of 88% or above and the swelling rate of 4100% or above, and the skin moisture can be increased by 32% after the mask is used for 15 minutes, so that the skin water-oil state is improved, and a better using effect is achieved.

Description

Technical Field

[0001] The invention relates to the field of biotechnology, and in particular to a preparation method and application of a sodium alginate hydrogel mask with a high water content. Background Art

[0002] Facial masks are a readily available commodity that is easy to use and has an immediate effect on the skin. Bioactive ingredients with different mechanisms of action are added to facial masks to give them skin-rejuvenating properties, including moisturizers, exfoliants, whitening and herbal ingredients, different types of vitamins, proteins, minerals, growth factors and other substances. The facial masks used are expected to properly and deeply moisturize the skin, remove sebum and rejuvenate the skin.

[0003] Commercially available moisturizing masks are usually paper masks with fixed facial contours, which are directly applied to the face after being combined with mask essence. Although this type of mask provides convenience, it also has some disadvantages. For example, different people have different facial contours and features, and fixed-shape masks may not fit everyone's face perfectly, resulting in some areas not being covered or gaps between the mask and the skin. The size of the mask may not fit everyone's face size, and may not provide adequate coverage for users with larger or smaller faces. In addition, fixed-shape masks may not be suitable for all skin types or facial conditions, such as sensitive skin or users with special care needs. Therefore, it is particularly important to create a mask that has a high moisturizing effect and can be customized in shape and size.

[0004] Hydrogels are three-dimensional polymer networks with extremely high water content and effective moisturizing properties. The hydrophilic base of the hydrogel creates a matrix for the skin that allows active ingredients to enter the skin efficiently. Thermosensitive hydrogels are particularly suitable for localized, controlled and continuous delivery of active compounds based on the fact that thermal stimulation causes changes in the conformation, solubility and hydrophilic / hydrophobic balance of the active compounds. Their formulation and properties can be adjusted according to the release kinetics of the bioactive ingredients; therefore, they are of great significance in skin care and skin treatment as transdermal drug delivery systems.

[0005] Sodium alginate is widely used as a gelling agent because it can form gels with divalent cations such as calcium under mild conditions. Sodium alginate is first dissolved in water to form a solution containing sodium ions and alginate. When a solution containing calcium ions is added to the solution, the calcium ions exchange ions with the carboxyl groups in the alginate, replacing the sodium ions in the alginate. The calcium ions form strong ionic bonds with the carboxyl groups of the alginate, resulting in cross-linking between the sodium alginate molecular chains. This cross-linking rapidly increases the viscosity of the solution and forms a three-dimensional network structure. As more calcium ions bind to the alginate, the three-dimensional network structure formed becomes more stable, eventually forming gel blocks or beads with a certain mechanical strength. However, the sodium alginate gel microspheres may not be sufficiently formed to reach the level of practical use, and the gelation method needs to be further improved. At present, calcium alginate gel has been used in wound dressings, dental impression materials, controlled release drug delivery systems and living cell encapsulation.

[0006] However, how to obtain a mask with high retention rate and high swelling rate while also being able to customize the appearance and provide regional skin care is currently not feasible. Summary of the invention

[0007] The present invention provides a method for preparing a sodium alginate hydrogel mask with a high water content, which utilizes the gelling principle of sodium alginate and calcium ions, and adds components such as zinc hyaluronate, carbomer 941 and poloxamer during the production process, so as to quickly obtain a smooth and transparent mask with a customizable appearance, and can provide regional skin care. In addition, the mask not only has a moisturizing rate of more than 87%, but also can reach a swelling rate of more than 4100%, and can absorb other whitening, anti-inflammatory and other essence components, thereby improving skin moisture and achieving a better use effect.

[0008] On one hand, the present invention provides a method for preparing a sodium alginate hydrogel mask with a high water content, comprising: applying solution A into a specific shape, then applying solution B to the surface of solution A having the specific shape, and obtaining a sodium alginate hydrogel mask with a self-defined shape after a cross-linking reaction between solution A and solution B; solution A is a sodium alginate solution with a mass concentration range of 1%-7%; solution B is a calcium ion solution with a concentration range of 100-400mM, which contains poloxamer, zinc hyaluronate, and carbomer 941.

[0009] In some embodiments, the cross-linking reaction time of solution A and solution B is 10 seconds.

[0010] In some embodiments, the volume ratio of solution A and solution B is 1:2-3:1, including 1:2, 1:1.5, 1:1, 3:2, 2:1, 5:2, 3:1, the more optimal range of volume ratio is 1:1-3:1, and the optimal ratio is 2:1.

[0011] In some embodiments, the sodium alginate concentration of solution A may range from 3% to 6%, with 5% being the most preferred.

[0012] In some embodiments, in the solution B, the concentration of calcium ions ranges from 100mM, 110mM, 120mM, 130mM, 140mM, 150mM, 160mM, 170mM, 180mM, 190mM, 200mM, 210mM, 220mM, 230mM, 240mM, 250mM, 260mM, 270mM, 280mM, 290mM, 300mM, 310mM, 320mM, 330mM, 340mM, 350mM, 360mM, 370mM, 380mM, 390mM, and 400mM, with 200mM being the optimal choice.

[0013] The calcium ion solution is a solution formed by dissolving a soluble calcium salt in sterile water for injection (physiological saline, phosphate buffer solution, etc. may also be used), and the soluble calcium salt includes one or more of calcium chloride, calcium bromide, calcium nitrate, calcium chlorate, etc. Preferably, the soluble calcium salt is calcium chloride.

[0014] In some embodiments, the concentration of carbomer 941 in solution B ranges from 1% to 3%, with the optimal concentration being 2%; the concentration of poloxamer ranges from 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, and 30%, with the optimal concentration being 20%; and the concentration of zinc hyaluronate is 0.2%.

[0015] Zinc hyaluronate is the zinc salt form of hyaluronic acid, which can greatly improve the absorption rate of hyaluronic acid in the human body compared with sodium hyaluronate. Zinc hyaluronate has a strong moisturizing effect and can combine more than 400 times of its own weight of water. In addition, zinc hyaluronate also has antioxidant and soothing effects. A trace amount of zinc hyaluronate (Huaxi Biology) is added to the B component of the present invention. The general amount used in this area is less than 0.5%. Since the absorption rate of the components is not greatly affected within this range, the present invention selects a commonly used antibacterial moisturizing dosage of 0.2%. Carbomer 941 is a polymer commonly used in personal care products and pharmaceutical preparations, which can reduce the loss of moisture and nutrients in the skin, delay skin aging, and has an anti-inflammatory effect, can improve the skin redness and local swelling caused by improper cleaning or inflammatory stimulation, in addition, carbomer 941 also has a bactericidal effect, and can improve the skin redness and local swelling caused by improper cleaning or inflammatory stimulation. Poloxamer is a non-ionic block copolymer widely used in medicine and cosmetics. It can increase skin permeability and promote the absorption of topical medications. Poloxamer hydrogel is temperature-sensitive and can be used to prepare thermosensitive sustained-release and controlled-release preparations, such as long-acting injections and long-acting eye drops.

[0016] In some embodiments, the solution B also includes 1,2-hexanediol and glycerin to further moisturize and preserve, and additional ingredients such as whitening and antioxidant ingredients may be added.

[0017] 1,2-Hexanediol has multiple effects in cosmetics and personal care products. It combines with moisture on the skin to form a molecular film, helps lock moisture, maintain skin moisture level, and has a certain antibacterial effect. The present invention uses 1,2-Hexanediol (Aladdin, H108067) at a common dosage of 3%. Glycerin (propylene glycol) is a polyol widely used in cosmetics and personal care products. It is a powerful moisturizer that helps the skin retain moisture and avoids dryness. In addition, glycerin may have a slight anti-inflammatory effect and help alleviate skin inflammation. Among pharmaceutical excipients, glycerin (Aladdin, G116203) can be applied topically up to 50%. Considering the fluidity and safety of component B, the present invention finally uses 3%.

[0018] Another aspect of the present invention provides the application of the preparation method of the sodium alginate hydrogel mask in the field of skin care and health care.

[0019] The technical solution of the present invention has the following beneficial effects: (1) The sodium alginate facial mask of the present invention can be customized into a clear and smooth gel facial mask of different shapes according to facial needs. (2) The sodium alginate facial mask of the present invention has a swelling rate of more than 4100%, and can absorb more essence to meet the needs of whitening, etc. (3) The sodium alginate facial mask of the present invention has a balanced water content of more than 97% and a 37°C indoor moisturizing rate of more than 88%. (4) The sodium alginate facial mask of the present invention can increase the moisture content of the skin by 32% and has excellent skin moisturizing properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The figure shows the gel formation of sodium alginate gel mask;

[0021] Figure 2 A schematic diagram of a gel mask square is shown (black frame);

[0022] Figure 3 The weight variation curve of the sodium alginate film over time is shown;

[0023] Figure 4 The weight variation curve of the sodium alginate dry film during water absorption is shown;

[0024] Figure 5 The figure shows the comparison of skin moisture changes after applying sodium alginate mask and commercially available mask. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical scheme and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments and drawings. The specific embodiments described herein are only used to explain the present invention and are not intended to constitute any limitation to the present invention. In addition, in the following description, the description of known structures and technologies is omitted to avoid unnecessary confusion of the concepts of the present disclosure. Such structures and technologies are also described in many publications.

[0026] The reagents used in the following examples are as follows: sodium alginate, Aladdin, S100126, viscosity 200±20 mPa.s; calcium chloride, Solebol, G0070; carbomer 941, Xinrunde, cas9003-01-4; poloxamer, Aladdin, P434419; sodium alginate, Aladdin, S100126, viscosity 200±20 mPa.s.

[0027] Unless otherwise specified, all experimental methods were conventional methods.

[0028] Other materials and reagents used, unless otherwise specified, can be obtained from commercial sources.

[0029] Example 1 Exploration of the concentration of sodium alginate in component A of solution

[0030] Prepare a sodium alginate solution with a mass concentration of 0.5%-7% and a 100mM calcium chloride solution respectively. Spread 1mL of the sodium alginate solution on the bottom of a culture dish, add 0.5mL of the calcium chloride solution, stir, and observe the gelation state and gelation time.

[0031] Cross-linking time is the time it takes for the material structure to change, that is, the time it takes to change from a solution state to a sol state. Considering the use scenarios of gel masks, a time shorter than 10 seconds will increase the difficulty of actual use, and a time too long will reduce user satisfaction. Therefore, a gelling time of 10-20 seconds is more conducive to the use of the mask on the skin and meets the needs of users. In addition, 8% sodium alginate is difficult to dissolve, so it will no longer be optimized for use in the future.

[0032] The experimental results are shown in Table 1. Based on the experimental results, it is determined that the optional concentration range of sodium alginate in the final gel mask product is 1%-7%, the suboptimal range is 3%-6%, the more preferred range is 4%-6%, and the optimal range is 5%.

[0033] Table 1: Sodium alginate concentration exploration experiment record

[0034]

[0035] Example 2 Solution B core component concentration exploration test

[0036] The concentrations of carbomer 941, calcium chloride, poloxamer in component B and sodium alginate in component A play an important role in the gel formation rate of the gel mask, so it is necessary to explore their appropriate concentrations through experiments.

[0037] The standard orthogonal table 16.4.4 was used to perform the orthogonal experimental design in Table 2 to prepare calcium ion solution and sodium alginate solution. The sodium alginate solution was prepared by dissolving water, and the other components in the calcium ion solution were glycerol, zinc hyaluronate and 1,2-hexanediol.

[0038] Table 2: Orthogonal experimental design table

[0039]

[0040] Take 2mL of sodium alginate solution and apply it on the skin, with an area of ​​about 6cm*6cm and a thickness of 2mm. Take 1mL of calcium ion solution and spread it on the sodium alginate, observe the gelation time, peeling state and uniform state of each component, and finally determine the parameters of moderate gelation reaction time (10 seconds), easy removal of the mask and smooth and uniform surface.

[0041] According to the test results, the range of sodium alginate in component A is 4%-6%, and the optimal choice is 5%. The range of calcium chloride concentration in component B is 100-400mM, and the optimal choice is 200mM. The range of carbomer 941 concentration in component B is 1%-3%, and the optimal choice is 2%. The range of poloxamer concentration in component B is 10%-30%, and the optimal choice is 20%.

[0042] Example 3 A, B colloid ratio exploration test

[0043] After exploring the optimal range of components A and B, the final exploratory experiment was conducted on the gelling reaction ratio and method. According to the optimal formula of components A and B, components A and B were prepared, and the gelling reaction was carried out at different volume ratios as shown in Table 3. The gelling state and gelling time were observed, and the results are shown in Table 3.

[0044] According to the test results, the ratio of component A to component B is in the range of 1:2-3:1, the better range is 1:1-3:1, and the optimal ratio is 2:1.

[0045] Table 3: A and B group allocation ratio exploration experiment record

[0046]

[0047] Example 4 Preparation of Sodium Alginate Hydrogel Mask

[0048] The component A used in this example is a sodium alginate solution, and the basic solvent is sterile water for injection. 40 mL of sterile water for injection is taken into a 50 mL centrifuge tube, 2 g of sodium alginate is weighed and added to the liquid surface of the centrifuge tube and shaken vigorously to make the sodium alginate evenly distributed, and shaken at room temperature overnight to make it fully swell to obtain a 5% sodium alginate solution.

[0049] The component B used in this embodiment is a calcium ion solution, the basic solvent is a calcium chloride solution and water, and the final concentration of the component formula is shown in Table 4:

[0050] Table 4: Final concentration formula of calcium ion solution

[0051] Serial number Reagents concentration 1 Calcium chloride 200mM 2 Carbomer 941 2%(w / v) 3 Poloxamer 20%(w / v) 4 glycerin 3%(v / v) 5 Zinc Hyaluronate 0.2%(w / v) 7 1,2-Hexanediol 3%(v / v)

[0052] Take 1mL of component A and 0.5mL of component B and add them to a glass bottle. After mixing for 10 seconds, cross-linking occurs and the solution turns into a gel state. Invert the glass bottle and you can see that the gel is adsorbed on the bottom of the bottle without flowing. Figure 1 The film can be completely removed and is smooth, transparent, and has a uniform texture. After the film is removed, no liquid remains at the bottom of the bottle.

[0053] Application of the sodium alginate hydrogel mask prepared in Example 5

[0054] Prepare component A and component B according to the conditions of Example 4, apply 2 mL of component A on the skin, with an area of ​​6 cm*6 cm and a thickness of 2 mm. Spread 1 mL of component B solution on component A, let it stand for 10 seconds, and then peel off the mask completely from the edge to obtain a clear and smooth gel mask.

[0055] Use absorbent paper to absorb excess moisture on the surface, place it on a balance and weigh it, and record the initial weight of the membrane. Spread the membrane flat in a culture dish and place it in a 60°C forced air drying oven. Measure the weight every 5 minutes until the weight remains stable, and record the weight change of the membrane. Soak the dried membrane in 25°C saline, take it out at different time points, use absorbent paper to absorb excess moisture on the surface, and then weigh it, and record the weight change of the membrane. Use Graphdprism to statistically analyze the weight change of the membrane. The weight change of the gel mask in the drying oven over time is shown in the figure. Figure 3 As shown in Figure 2, after 2 hours, the weight of the membrane remained stable, and the texture of the final membrane was similar to hard plastic. Figure 4 As shown, after 45 minutes, the weight of the film remained stable, indicating that the mask has good water-locking and water-absorbing properties. It can lock facial moisture during actual use, while absorbing more facial essence, moisturizing the skin and providing higher vitality for skin cells.

[0056] Example 6 Swelling rate test

[0057] According to the conditions and method of Example 4, a clear and smooth gel mask was obtained, and four parallel groups were set up in each group.

[0058] Use absorbent paper to absorb excess moisture on the surface, place it on a balance and weigh it, and record the initial weight of the membrane m0. Spread the membrane flat in a culture dish and place it in a 60°C forced air drying oven. Measure the weight every 10 minutes until the weight remains stable, and record the dry weight of the membrane m1. Soak the dried membrane in 25°C saline for 10 minutes, use absorbent paper to absorb excess moisture on the surface and weigh it, and record the saturated weight of the membrane m2. Spread the saturated membrane flat in a culture dish and place it in a 37°C constant temperature box. After 30 minutes, take it out and measure the weight of the mask m3. Calculate the swelling rate, equilibrium water content and moisturizing rate of the sodium alginate gel mask according to the following formulas:

[0059] Swelling rate = (saturated weight m2-dry weight m1) / dry weight m1*100%

[0060] Equilibrium moisture content = (saturated weight m2-dry weight m1) / saturated weight m2*100%

[0061] Moisture retention rate = 100 - water loss rate = 100 - [(saturated weight m2-m3) / saturated weight m2*100%]

[0062] The experimental results are shown in Table 5. The sodium alginate mask has a swelling rate of more than 4100%, a balanced water content of more than 97% and a moisturizing property of more than 88%. In subsequent use, it can not only achieve a high moisturizing effect, but also absorb more essence to meet the needs of whitening.

[0063] Table 5: Gel mask quality changes and analysis results

[0064] Group 1 2 3 4 Dish weight 9.645 9.935 9.833 8.282 Membrane weight m0 0.396 0.407 0.425 0.402 Membrane + dish 10.041 10.342 10.258 8.684 10min 9.865 10.287 9.998 8.605 20min 9.784 10.225 9.962 8.594 30min 9.731 10.067 9.935 8.421 40min 9.659 9.948 9.849 8.297 Membrane dry weight m1 0.014 0.013 0.016 0.015 Saturated weight m2 0.632 0.657 0.696 0.640 37℃Weight m3 0.561 0.585 0.637 0.594 Swelling rate (%) 4414.29 4953.85 4250.00 4166.67 Equilibrium moisture content (%) 97.78 98.02 97.70 97.66 Moisture retention after 30 minutes (%) 88.77 89.04 91.52 92.81

[0065] Example 7 Skin Test

[0066] 30 healthy female volunteers aged 20-35 were selected and randomly divided into two groups (no other cosmetics were used 72 hours before the experiment), 15 people in each group, and tried the gel mask obtained in Example 3 and the commercially available moisturizing mask respectively. The volunteers rested for 30 minutes in a room at 26°C and 50% relative humidity. The skin moisture and oil content were measured using a skin tester, and the initial state was recorded. The sodium alginate mask and the commercially available moisturizing mask samples were covered on the inner side of the right forearm of the volunteers. The gel mask was removed after 15 minutes, and the skin moisture and oil content were measured using a skin tester after 15 minutes, 30 minutes, 60 minutes and 120 minutes, respectively. The skin tester was used to measure the skin moisture and oil content, and the test was repeated 3 times each time to obtain the detection average value.

[0067] The skin measurement results of the sodium alginate mask are shown in Table 6, and the skin measurement results of the commercially available mask are shown in Table 7.

[0068] The moisture change rate of the sodium alginate mask and the commercially available mask 15 minutes and 120 minutes after application was statistically analyzed. 15 minutes after application, the moisture content of the sodium alginate mask group increased by 32.36±3.17%, and the moisture content of the commercially available mask increased by 18.51±1.24%. The T test was performed using Graphd Prism, and the P value between the two groups was 0.002, indicating a significant difference. 120 minutes after the mask was removed, the moisture content of the sodium alginate mask group increased by 14.25±2.21%, and the moisture content of the commercially available mask increased by 4.44±0.71%. The P value between the two groups was 0.0014, indicating a significant difference. The results are as follows Figure 5 As shown, the moisturizing effect of sodium alginate mask on the skin is significantly higher than that of commercially available moisturizing masks.

[0069] Table 6: Changes in skin moisture and oil content of volunteers wearing sodium alginate mask at different times

[0070]

[0071] Table 7: Changes in skin moisture and oil content of volunteers using commercially available moisturizing masks at different times

[0072]

[0073]

[0074] Although the present invention has been described in detail above with general descriptions and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements may be made thereto based on the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all fall within the scope of protection claimed by the present invention.

Claims

1. A method for preparing a sodium alginate hydrogel mask with a high water content, comprising: Solution A is applied into a specific shape, and then solution B is applied to the surface of solution A with a specific shape. After the cross-linking reaction between solution A and solution B, a sodium alginate hydrogel mask with a self-defined shape can be obtained; the solution A is a sodium alginate solution with a mass concentration range of 1%-7%; the solution B is a calcium ion solution with a concentration range of 100-400 mM, which contains poloxamer, zinc hyaluronate, and carbomer 941.

2. The method for preparing the sodium alginate hydrogel facial mask according to claim 1, characterized in that: The volume ratio of solution A to solution B is 1:2-3:

1.

3. The method for preparing the sodium alginate hydrogel facial mask according to claim 2, characterized in that: The cross-linking reaction time of the solution A and the solution B is 8-12 seconds.

4. The method for preparing the sodium alginate hydrogel facial mask according to claim 3, characterized in that: The mass concentration of sodium alginate in the solution A is in the range of 3% to 6%.

5. The method for preparing the sodium alginate hydrogel facial mask according to claim 1, characterized in that: The concentration range of the calcium ion solution is 200 mM.

6. The method for preparing the sodium alginate hydrogel facial mask according to claim 5, characterized in that: The mass concentration of carbomer 941 in the solution B is in the range of 1%-3%, the mass concentration of poloxamer is in the range of 10%-30%, and the mass concentration of zinc hyaluronate is 0.2%.

7. The method for preparing the sodium alginate hydrogel facial mask according to claim 6, characterized in that: In the solution B, the mass concentration of carbomer 941 is 2%, the mass concentration of poloxamer is 20%, and the mass concentration of zinc hyaluronate is 0.2%.

8. The method for preparing the sodium alginate hydrogel facial mask according to claim 7, characterized in that: The solution B also includes 1,2-hexanediol and glycerol.

9. The method for preparing the sodium alginate hydrogel facial mask according to claim 8, characterized in that: The volume ratio of solution A to solution B is 2:1; the mass concentration of sodium alginate in solution A is 5%, the concentration of calcium ions in solution B is 200 mM, the mass concentration of carbomer 941 is 2%, the mass concentration of poloxamer is 20%, the mass concentration of zinc hyaluronate is 0.2%, the volume ratio of 1,2-hexanediol is 3%, and the volume ratio of glycerol is 3%.

10. Application of the preparation method of the sodium alginate hydrogel mask according to any one of claims 1 to 9 in the field of skin care and health care.

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