A w / o / w compound emulsion and a preparation method and application thereof
By using a dual-layer encapsulation technology of hydrophobic bacterial cellulose and cinnamaldehyde, the safety and stability issues of W/O/W composite emulsions have been resolved, achieving longer drug release and antibacterial time, and improving the efficacy and safety of skincare products.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- QILU UNIVERSITY OF TECHNOLOGY (SHANDONG ACADEMY OF SCIENCES)
- Filing Date
- 2023-12-11
- Publication Date
- 2026-06-23
Smart Images
Figure BDA0004599233340000081
Abstract
Description
Technical Field
[0001] This invention relates to the field of composite emulsion technology, and more particularly to a W / O / W composite emulsion, its preparation method, and its application. Background Technology
[0002] The information disclosed in the background section of this invention is intended only to enhance the understanding of the overall background of the invention and is not necessarily to be construed as an admission or in any way implying that such information constitutes prior art known to those skilled in the art.
[0003] Skincare products have become an indispensable part of daily life. People not only pay attention to the effectiveness of skincare products, but also their safety and timeliness. Most products on the market are single-emulsion lotions, which may have a significantly shortened effectiveness due to rapid emulsification during application. In addition, the emulsifiers in these lotions are generally chemically synthesized chemicals, which may more or less affect human skin.
[0004] To address this issue, researchers have attempted to develop W / O / W composite emulsions. These emulsions encapsulate the drug in two ways, protecting the water-soluble drug and significantly extending its release time, resulting in longer-lasting effects. However, current W / O / W composite emulsions still have limitations. For example, they often use traditional chemical emulsifiers like Tween and Span, which have relatively poor safety profiles; and the sustained release of the drug into the aqueous phase is susceptible to bacterial contamination. Therefore, developing W / O / W composite emulsions that offer high safety, long-lasting antibacterial activity, and good stability is a pressing technical challenge. Summary of the Invention
[0005] In view of this, the present invention provides a W / O / W composite emulsion, its preparation method and application. The composite emulsion has good safety and stability, and has a long antibacterial time, a long drug sustained release time, and a longer duration of effectiveness.
[0006] In a first aspect, the present invention provides a method for preparing a W / O / W composite emulsion, comprising the following steps:
[0007] Cinnamaldehyde, hydrophobic bacterial cellulose, and oil are mixed to prepare an oil phase (O); the oil phase is mixed with an aqueous solution of nutrients (W1) and homogenized to prepare a W1 / O promulgated emulsion; the W1 / O promulgated emulsion is mixed with an aqueous solution containing bacterial cellulose (W2) and homogenized to obtain the final product.
[0008] The hydrophobic bacterial cellulose is obtained by hydrophobic modification of bacterial cellulose.
[0009] Preferably, the nutrients include, but are not limited to, one or more of tea polyphenols, sodium hyaluronate, or amino acids, which have anti-aging, allergy-relieving, radiation-protective, moisturizing, and skin-elasticity-enhancing effects. Preferably, the concentration of the nutrients in the aqueous solution is 0.01-0.1%.
[0010] Preferably, the concentration of cinnamaldehyde in the oil phase system (O) is 0.001-0.1%. Cinnamaldehyde has bactericidal, disinfectant, and antiseptic effects, especially against fungi. It has inhibitory effects on Escherichia coli, Bacillus subtilis, Staphylococcus aureus, Staphylococcus albus, Shigella dysenteriae, Salmonella typhi and paratyphi A, Streptococcus pneumoniae, Enterobacter aerogenes, Proteus, Bacillus anthracis, Salmonella enteritidis, and Vibrio cholerae, and has a significant bactericidal effect on Gram-positive bacteria. It can be used to treat various diseases caused by bacterial infections. Cinnamaldehyde is poorly soluble in water and easily oxidized in air. This invention dissolves it in the oil phase and avoids volatilization, discoloration, and oxidation of cinnamaldehyde in air by encapsulating it in an external aqueous phase. At the same time, the slow release of cinnamaldehyde also ensures that the drug is not contaminated by bacteria after slow release, improving the antibacterial properties of the composite emulsion and thus extending the shelf life.
[0011] Preferably, the concentration of hydrophobic bacterial cellulose in the oil phase system (O) is 0.3-0.5%; and the concentration of bacterial cellulose in the aqueous solution (W2) containing bacterial cellulose is 0.3-0.5%. Bacterial cellulose is a naturally occurring nanostructured polymer material mainly produced by bacteria. It is a linear polymer composed of β-D-glucose linked by β-1,4-glycosidic bonds. These molecular chains contain many hydroxyl groups and are assembled stepwise in a specific manner, exhibiting good biocompatibility and biodegradability. Furthermore, bacterial cellulose has good dispersibility and suspension stability, and a large specific surface area, allowing it to adsorb onto the oil-water interface to form a stable emulsion. The inventors have discovered that hydrophobic bacterial cellulose more readily forms water-in-oil emulsions when stabilizing emulsions. Therefore, this invention uses hydrophilic bacterial cellulose as a water-soluble emulsifier and hydrophobic bacterial cellulose as an oil-soluble emulsifier, replacing traditional emulsifiers such as Tween and Span, thus improving the safety of the composite emulsion.
[0012] Preferably, the hydrophobic bacterial cellulose is obtained by hydrophobic modification of bacterial cellulose with alkoxysilane; the alkoxysilane is selected from any one of methyltrimethoxysilane, dodecyltrimethoxysilane, or propanetrimethoxysilane. Alkoxysilane modification greatly improves the hydrophobicity of cellulose.
[0013] More preferably, the preparation process of the hydrophobic bacterial cellulose is as follows: alkoxysilane is mixed and stirred with bacterial cellulose under acidic conditions to obtain the final product.
[0014] Preferably, the pH value of the acidic condition is 3 to 5; preferably, the mass ratio of the alkoxysilane to bacterial cellulose is 3:1 to 1:3; preferably, the stirring reaction time is 2 to 6 hours.
[0015] Preferably, the oil includes, but is not limited to, fish oil, jojoba oil, olive oil, shea butter, tea seed oil, or almond oil. All oils provided are natural oils with good safety profiles, are non-irritating to the skin, and provide moisturizing and barrier functions.
[0016] Preferably, the volume ratio of the nutrient aqueous solution W1 to the oil phase O is 1:1 to 6; the volume ratio of the total volume of the nutrient aqueous solution W1 and the oil phase O to the volume of the aqueous solution W2 containing bacterial cellulose is (W1+O) / W2 = 1:1 to 6.
[0017] Preferably, the homogenization emulsification time is 1 to 5 minutes.
[0018] Secondly, the present invention provides a W / O / W composite emulsion prepared by the above preparation method.
[0019] Thirdly, the present invention provides the application of the above-mentioned W / O / W composite emulsion in the field of skin care products.
[0020] Compared with the prior art, the present invention has achieved the following beneficial effects:
[0021] (1) The present invention encapsulates the nutrients in a W / O emulsion to achieve the purpose of slow release of nutrients; the secondary encapsulation of the W / O / W composite emulsion further extends the slow release time of the nutrients, and cinnamaldehyde in the oil phase is released outwards at the same time, ensuring that the released nutrients are not contaminated by bacteria, extending the antibacterial time, and thus extending the shelf life of the composite emulsion; in addition, the encapsulation method of the W / O / W composite emulsion protects the nutrients and cinnamaldehyde, which plays an antibacterial role.
[0022] (2) The present invention uses bacterial cellulose as a water-soluble emulsifier to stabilize the O / W2 emulsion and hydrophobic bacterial cellulose as an oil-soluble emulsifier to stabilize the W1 / O emulsion. It has good biocompatibility and safety, and the prepared composite emulsion has good stability.
[0023] (3) The W / O / W composite emulsion preparation method of the present invention is simple to operate, green and pollution-free, and has broad application prospects. Detailed Implementation
[0024] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.
[0025] It should be noted that the concentration of the substances described in this invention refers to the mass fraction of the corresponding substance in the corresponding system, that is, the number of grams of the substance in 100g of solution; for example, a concentration of 0.1% for hydrophobic bacterial cellulose and a concentration of 0.001% for cinnamaldehyde means that 100g of oil phase contains 0.1g of hydrophobic bacterial cellulose emulsifier and 0.001g of cinnamaldehyde. This invention does not impose any special restrictions on the source of raw materials; commercially available products well known to those skilled in the art can be used. This invention does not impose any special restrictions on the equipment used for homogenization and emulsification; equipment commonly used in the art can be used.
[0026] The technical solution of the present invention will be further described below with reference to specific embodiments.
[0027] Example 1
[0028] Hydrophobic bacterial cellulose was prepared by mixing methyltrimethylsilane solution with dry bacterial cellulose at a mass ratio of 1:1 and stirring for 4 hours.
[0029] Jojoba oil, cinnamaldehyde, and hydrophobic bacterial cellulose were used as the oil phase, with cinnamaldehyde concentration of 0.01% and hydrophobic bacterial cellulose concentration of 0.3%. The oil phase was mixed with a mixed aqueous solution of tea polyphenols, sodium hyaluronate, and amino acids with a total concentration of 0.05% and homogenized for 3 min. Then, it was homogenized and emulsified with a bacterial cellulose aqueous solution with a concentration of 0.3% for 3 min to obtain a W / O / W composite emulsion. The volume ratio of the aqueous solution of tea polyphenols, sodium hyaluronate, and amino acids (W1), oil phase (O), and aqueous solution containing bacterial cellulose (W2) was: W1:O = 1:4 and (W1+O) / W2 = 1:4.
[0030] Example 2
[0031] Hydrophobic bacterial cellulose was prepared by mixing methyltrimethylsilane solution with dry bacterial cellulose at a mass ratio of 1:2 and stirring for 5 hours.
[0032] Jojoba oil, cinnamaldehyde, and hydrophobic bacterial cellulose were used as the oil phase, with cinnamaldehyde concentration of 0.05% and hydrophobic bacterial cellulose concentration of 0.4%. The oil phase was mixed with a mixed aqueous solution of tea polyphenols, sodium hyaluronate, and amino acids with a total concentration of 0.07% and homogenized for 1 min. Then, it was homogenized with a bacterial cellulose aqueous solution with a concentration of 0.4% and homogenized for 1 min to obtain a W / O / W composite emulsion. The volume ratio of the aqueous solution of tea polyphenols, sodium hyaluronate, and amino acids (W1), oil phase (O), and aqueous solution containing bacterial cellulose (W2) was: W1:O = 1:4 and (W1+O) / W2 = 1:6.
[0033] Example 3
[0034] Hydrophobic bacterial cellulose was prepared by mixing methyltrimethylsilane solution with dry bacterial cellulose at a mass ratio of 1:3 and stirring for 6 hours.
[0035] Fish oil, cinnamaldehyde, and hydrophobic bacterial cellulose were used as the oil phase, with cinnamaldehyde concentration of 0.1% and hydrophobic bacterial cellulose concentration of 0.5%. The oil phase was mixed with a mixed aqueous solution of tea polyphenols, sodium hyaluronate, and amino acids with a total concentration of 0.1% and homogenized for 5 min. Then, it was homogenized and emulsified with a bacterial cellulose aqueous solution with a concentration of 0.5% for 5 min to obtain a W / O / W composite emulsion. The volume ratio of the nutrient aqueous solution W1, the oil phase O, and the aqueous solution containing bacterial cellulose W2 was: W1:O = 1:6, (W1+O) / W2 = 1:6.
[0036] Comparative Example 1
[0037] Compared with Example 3, the difference is that this comparative example directly uses Span 80 and Tween 60 to stabilize the emulsion; specifically, Span 80 is used instead of hydrophobic bacterial cellulose to stabilize the W1 / O colostrum, and Tween 60 is used instead of bacterial cellulose to stabilize the (W1 / O) / W2 composite emulsion; the concentration of Span 80 in the oil phase is 5%, and the concentration of Tween 60 in the Tween 60 aqueous solution is 5%.
[0038] Comparative Example 2
[0039] The difference between this example and Example 3 is that cinnamaldehyde was not added to the oil phase of this comparative example.
[0040] Comparative Example 3
[0041] The difference between this comparative example and Example 3 is that only W1 / O colostrum was prepared.
[0042] Specifically, a methyltrimethylsilane solution was mixed with bacterial cellulose at a mass ratio of 1:1 after being dried, and the mixture was stirred for 4 hours to prepare hydrophobic bacterial cellulose.
[0043] Jojoba oil, cinnamaldehyde, and hydrophobic bacterial cellulose were used as the oil phase, with cinnamaldehyde concentration of 0.01% and hydrophobic bacterial cellulose concentration of 0.3%. The oil phase was mixed with aqueous solutions of tea polyphenols, sodium hyaluronate, and amino acids, each at a concentration of 0.05%, and homogenized and emulsified for 3 min. The volume ratio of the aqueous solution of tea polyphenols, sodium hyaluronate, and amino acids (W1) to the oil phase (O) was W1:O = 1:4.
[0044] Comparative Example 4
[0045] Hydrophobic bacterial cellulose was prepared by mixing methyltrimethylsilane solution with dry bacterial cellulose at a mass ratio of 3:1 and stirring for 2 hours.
[0046] Fish oil, cinnamaldehyde, and hydrophobic bacterial cellulose were used as the oil phase, with cinnamaldehyde concentration of 0.001% and hydrophobic bacterial cellulose concentration of 0.1%. The oil phase was mixed with a mixed aqueous solution of tea polyphenols, sodium hyaluronate, and amino acids with a total concentration of 0.01% and homogenized for 1 min. Then, it was homogenized with a bacterial cellulose aqueous solution with a concentration of 0.1% and homogenized for 1 min to obtain a W / O / W composite emulsion. The volume ratio of the aqueous solution of tea polyphenols, sodium hyaluronate, and amino acids (W1), the oil phase (O), and the aqueous solution containing bacterial cellulose (W2) was: W1:O = 1:1 and (W1+O) / W2 = 1:1.
[0047] Comparative Example 5
[0048] Hydrophobic bacterial cellulose was prepared by mixing methyltrimethylsilane solution with dry bacterial cellulose at a mass ratio of 2:1 and stirring for 3 hours.
[0049] Fish oil, cinnamaldehyde, and hydrophobic bacterial cellulose were used as the oil phase, with cinnamaldehyde concentration of 0.005% and hydrophobic bacterial cellulose concentration of 0.2%. The oil phase was mixed with a mixed aqueous solution of tea polyphenols, sodium hyaluronate, and amino acids with a total concentration of 0.03% and homogenized for 2 min. Then, it was homogenized with a bacterial cellulose aqueous solution with a concentration of 0.2% and homogenized for 3 min to obtain a W / O / W composite emulsion. The volume ratio of the aqueous solution of tea polyphenols, sodium hyaluronate, and amino acids (W1), oil phase (O), and aqueous solution containing bacterial cellulose (W2) was: W1:O = 1:2 and (W1+O) / W2 = 1:2.
[0050] Test case
[0051] The stability, safety, and time-dependent properties of the emulsions prepared in Examples 1-5 and Comparative Examples 1-3 of this invention were tested. The test methods are as follows, and the test results are shown in Table 1.
[0052] Stability: Stability was tested by test tube settling and centrifugation. Settling method: The layering of different emulsions was observed after 31 days. Centrifugation stability was mainly tested by centrifugation at 4000 r / min for 10 min using a centrifugation stability tester (LUM GmbH Justus-von-Liebig-Str), and the layering of the emulsions after centrifugation was observed.
[0053] Safety: The antibacterial activity against Staphylococcus aureus and Escherichia coli was tested, and the diameter of the inhibition zone in the culture dish was observed after 24 hours.
[0054] Timeliness: After 31 days, the concentration of nutrients in the external water phase is measured. The longer the time for the drug concentration in the external water phase to increase, the better.
[0055] Table 1. Emulsion property determination of Examples 1-5 and Comparative Examples 1-3
[0056]
[0057] As shown in Table 1, the modification conditions in Example 1 were optimal. When bacterial cellulose was used as an emulsifier, it exhibited good stability, comparable to that of Comparative Example 1 using Span 80 and Tween 60 as emulsifiers, while requiring a lower dosage and demonstrating higher safety. When the volume ratio of the nutrient aqueous solution W1, oil phase O, and bacterial cellulose-containing aqueous solution W2 was W1:O = 1:4 and (W1:O) / W2 = 1:4, the emulsion exhibited both good stability and excellent drug release. A comparison of Examples 2, 3, and Example 1 shows that increasing the amount of bacterial cellulose did not significantly improve the antibacterial effect. This may be because the higher amount of bacterial cellulose hindered the release of the nutrient aqueous solution and cinnamaldehyde. In summary, Examples 1-3 all demonstrated good emulsion stability and good antibacterial properties.
[0058] As can be seen from the comparison between Example 1 and Comparative Example 2, the addition of cinnamaldehyde significantly improves the resistance of the emulsion to bacteria, which will greatly extend the shelf life of the emulsion.
[0059] A comparison of Example 1 and Comparative Example 3 reveals that the antibacterial time of the W / O / W composite emulsion is significantly longer than that of the W / O primary emulsion. This may be because some cinnamaldehyde evaporates or oxidizes with the air when the oil phase of the W / O primary emulsion comes into contact with air, which greatly diminishes the antibacterial effect of cinnamaldehyde. The W / O / W composite emulsion solves this problem through double-layer encapsulation, extending the product's shelf life.
[0060] The comparison between Example 1 and Comparative Examples 4 and 5 of the present invention reveals that when the concentration of hydrophobic bacterial cellulose and bacterial cellulose is less than 0.3%, the emulsion has poor stability and low practicality.
[0061] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. A method for preparing a W / O / W composite emulsion, characterized in that, Includes the following steps: Cinnamaldehyde, hydrophobic bacterial cellulose, and oil are mixed to prepare an oil phase; the oil phase is then mixed with an aqueous solution of nutrients and homogenized to prepare a W1 / O pre-emulsion; the W1 / O pre-emulsion is then mixed with an aqueous solution W2 containing bacterial cellulose and homogenized to obtain the final product; the hydrophobic bacterial cellulose is obtained by hydrophobic modification of bacterial cellulose with alkoxysilane; the alkoxysilane is selected from any one of methyltrimethoxysilane, dodecyltrimethoxysilane, or propanetrimethoxysilane; the mass ratio of the alkoxysilane to bacterial cellulose is 3:1 to 1:3; the preparation process of the hydrophobic bacterial cellulose is as follows: alkoxysilane and bacterial cellulose are mixed and stirred under acidic conditions to obtain the final product; In the oil phase, the concentration of cinnamaldehyde is 0.001~0.1%, and the concentration of hydrophobic bacterial cellulose is 0.3~0.5%. The oil includes fish oil or jojoba oil; The volume ratio of the nutrient aqueous solution W1 to the oil phase O is W1:O 1:4; the volume ratio of the total volume of the nutrient aqueous solution W1 and the oil phase O to the volume of the aqueous solution W2 containing bacterial cellulose is (W1+O) / W2 = 1:4 or 1:
6.
2. The preparation method according to claim 1, characterized in that, The nutrients include one or more of tea polyphenols, sodium hyaluronate, or amino acids, and the concentration of the nutrients in the aqueous solution is 0.01-0.1%.
3. The preparation method according to claim 1, characterized in that, The concentration of bacterial cellulose in the aqueous solution containing bacterial cellulose is 0.3-0.5%.
4. The preparation method according to claim 1, characterized in that, The homogenization emulsification time is 1-5 minutes.
5. The preparation method according to claim 1, characterized in that, The pH value of the acidic conditions is 3 to 5.
6. The preparation method according to claim 1, characterized in that, The stirring reaction time is 2-6 hours.
7. The W / O / W composite emulsion prepared by the preparation method according to any one of claims 1-6.
8. The application of the W / O / W composite emulsion according to claim 7 in the preparation of skin care products.
Citation Information
Patent Citations
CN113197855A
CN117164925A