A bionic sebum lipidosome, its preparation method, uses and cosmetics

Abstract

The present invention belongs to the field of new daily chemical materials, and discloses a preparation method of bionic sebum liposomes, which comprises the following steps: Step 1: Dissolve hydrogenated lecithin, cholesterol, Limnanthes alba seed oil, and ceramide NP in an organic solvent; the organic solvent includes methanol and dichloromethane; Step 2: Remove the organic solvent from the solution in Step 1 to obtain a lipid film; Step 3: Add butylene glycol and water to hydrate with the lipid film to form a crude liposome suspension; Step 4: Homogenize the crude liposome suspension 4 to 8 times under a pressure of 600-800 bar to obtain liposomes; by controlling the ratio of hydrogenated lecithin, cholesterol, ceramide NP, and Limnanthes alba seed oil, and combining with the thin film hydration method, the liposomes with high expression of barrier proteins can be prepared, which can better repair the skin barrier. At the same time, the present invention also discloses the application of the liposomes and cosmetics.

Description

Technical Field

[0001] The present invention belongs to the field of new daily chemical materials, and particularly relates to a biomimetic sebum liposome, a preparation method, a use thereof, and a cosmetic. Background Art

[0002] The skin is the outermost protective organ of the human body and the first natural barrier against the outside world, playing an important role in defending against external environmental invasions. The functions of the skin barrier are complex and diverse. Medically, according to its functions from the outside to the inside, it can be divided into four categories, namely, microbial barrier, chemical barrier, physical barrier, and immune barrier. These barriers work together to maintain the healthy state of the skin. Among them, the chemical barrier and the physical barrier play a crucial role in combating external irritants (such as microorganisms, toxic substances, ultraviolet rays, etc.) and maintaining the body's moisture and acidity. The chemical barrier is mainly composed of an acidic microenvironment formed by acidic substances and natural moisturizing factors, which can effectively inhibit and kill pathogenic microorganisms. The physical barrier is mainly composed of the stratum corneum and tight junction structures, which play a role in preventing the percutaneous penetration of chemical substances and microorganisms. The stratum corneum is composed of mature keratinocytes and intercellular lipids, which can not only seal and lock water but also resist the invasion of external substances. The adjacent keratinocytes in the granular layer form a tight barrier structure through tight junction proteins, which together with the stratum corneum ensure the function of the physical barrier. In the stratum corneum of healthy skin, keratinocytes and intercellular lipids are arranged in a stable brick-wall structure. Among them, keratinocytes are the "bricks", and intercellular lipids are the "mortar". The orderly and tight combination of the two ensures the integrity of the skin barrier.

[0003] The intercellular lipids in the stratum corneum are mainly composed of about 50% ceramides, 25% cholesterol, and 15% free fatty acids, which are important components for helping keratinocytes adhere tightly and maintaining the skin barrier function. The intercellular lipids are arranged in a liquid crystal ordered structure and form a dense lipid layer by repeating and stacking in a sandwich model, so as to achieve the sealing effect of resisting external stimulus invasion and reducing water loss. The periodic structure can be divided into a short-period phase (SPP) and a long-period phase (LPP). The former has a lamellar thickness of about 6 nm, and the latter has a lamellar thickness of about 13 nm.

[0004] The characteristics of damaged skin epidermal barrier include the reduction in the amount of intercellular lipids in the stratum corneum, the imbalance in proportion, and the destruction of the periodic structure, which exacerbate the invasion of irritants and cause skin sensitivity problems, or accelerate the loss of body moisture and cause skin dryness problems. Supplementing appropriate types and proportions of physiological lipids (such as the above-mentioned ceramides, cholesterol, free fatty acids) has become the main direction for cosmetic products to solve the problem of barrier damage. However, there are few relevant reports and studies on how to solve the skin barrier problem from the dimension of lipid biomimetic structure.

[0005] With the development of nanotechnology, the delivery technology of nanocarriers mainly based on liposomes has become an important means to promote the transdermal absorption of drugs and is also a hot spot in cosmetic technology. Liposomes have a liquid crystal structure of phospholipid bilayers. By encapsulating the above-mentioned physiological lipids (ceramide, cholesterol, fatty acid), a composite liquid crystal structure of phospholipid-ceramide-cholesterol-fatty acid is formed, which we believe can be used as a bionic repair method to supplement a structure similar to intercellular lipids.

[0006] CN116251036A discloses a composition for bionic intercellular lipids of keratinocytes and its preparation method, which is composed of the following raw materials in mass percentages: 1% - 10% ceramide mixture, 0.5 - 5% sterol, 0.3 - 3% vegetable oil, 5 - 30% solvent, 5 - 60% cosolvent, 2% - 70% deionized water, 1% - 15% lecithin or its derivatives;

[0007] It prepares bionic intercellular liposomes of keratinocytes by using the above raw materials through a high-throughput parallel droplet microfluidic system.

[0008] In the further research of this project, we believe that the skin barrier repair ability and barrier protein expression ability of bionic sebum liposomes are related to the following three aspects:

[0009] 1. Component bionics, the material selection of the formula should be as similar as possible to intercellular lipids;

[0010] 2. Proportion bionics, the material proportion of the formula should be as similar as possible to intercellular lipids;

[0011] 3. Structure bionics, the liquid crystal structure (such as wall thickness) of the liposome membrane should be as similar as possible to intercellular lipids.

[0012] Therefore, the technical problem to be solved in this project is: how to improve the skin barrier repair ability of bionic sebum liposomes and the expression of barrier proteins. Summary of the Invention

[0013] Aiming at the deficiencies of the prior art, the purpose of the present invention is to provide a bionic sebum liposome. By controlling the ratio of hydrogenated lecithin, cholesterol, ceramide NP, and Limnanthes alba seed oil, and combining with the thin film hydration method, liposomes with high expression of barrier proteins can be prepared, which can better repair the skin barrier.

[0014] Meanwhile, the present invention also discloses the application of this liposome and cosmetics.

[0015] To achieve the purpose of this invention, the present invention adopts the following technical solutions:

[0016] A preparation method of bionic sebum liposomes, comprising the following steps:

[0017] Step 1: Dissolve hydrogenated lecithin, cholesterol, Limnanthes alba seed oil, and ceramide NP in an organic solvent;

[0018] The organic solvent includes methanol and dichloromethane; the volume ratio of methanol to dichloromethane is 3:1.5 - 2.5; the total volume of methanol and dichloromethane is not less than 65% of the volume of the organic solvent;

[0019] Step 2: Remove the organic solvent from the solution in Step 1 to obtain a lipid film;

[0020] Step 3: Add butanediol and water to hydrate with the lipid film to form a crude liposome suspension;

[0021] Step 4: Homogenize the crude liposome suspension 4 - 8 times under a pressure of 600 - 800 bar to obtain liposomes;

[0022] The liposomes contain 4 - 6 wt% of hydrogenated lecithin, 0.4 - 0.6 wt% of cholesterol, 0.2 - 0.4 wt% of Limnanthes alba seed oil, and 0.8 - 1.2 wt% of ceramide NP.

[0023] In some preferred embodiments of the present invention, the volume ratio of methanol to dichloromethane can be selected as 3:1.5, 3:2, or 3:2.5;

[0024] The present invention realizes the bionics of the composition, ratio, and structure of liposomes through the optimization of the liposome formula, ratio, and selection of a suitable liposome preparation process;

[0025] First, this solution selects the ratio of cholesterol to ceramide NP to be close to 1:2, which is the main component of intercellular lipids. For free fatty acids, the present invention only selects Limnanthes alba seed oil. As the only plant oil present in this formula, Limnanthes alba seed oil has strong oxidation stability and is not easily deteriorated. It can enhance the skin barrier, especially for liposomes prepared by the thin - film hydration method, and the function of Limnanthes alba seed oil in repairing the skin barrier is more significant; the selection of the above - mentioned materials and ratios completely mimics intercellular lipids, achieving composition bionics and ratio bionics;

[0026] Secondly, the thin - film hydration method is used to prepare liposomes. Compared with the micro - channel method for preparing liposomes, the method of the present invention has unique advantages. Compared with the micro - channel method, the preparation process of the thin - film hydration method is simple and does not require the additional addition of an oily solvent as an oil - phase medium to dissolve lipophilic solids. Excessive oily amorphous components will affect the formation of liposomes and will transform into oil - in - water emulsions rather than bilayer liposomes. The liposome structure obtained by the thin - film hydration method is more complete. When combined with Limnanthes alba seed oil, it can significantly promote the expression of skin - barrier - related proteins.

[0027] In the above method for preparing the bionic sebum liposome, the organic solvent further contains one or two of chloroform and n-hexane.

[0028] In the above method for preparing the bionic sebum liposome, the organic solvent is composed of methanol, dichloromethane, and n-hexane; the volume ratio of methanol, dichloromethane, and n-hexane is 3:1.5 - 2.5:1 - 2.

[0029] For further demonstration and research on the solution of the present invention, methanol, dichloromethane, and n-hexane were selected as the solvent phase. The three can improve the solubility of liposome raw materials, and n-hexane can improve the tightness of the arrangement of Limnanthes alba seed oil in the film. After preparing the film under reduced pressure, through hydration and multiple high-pressure homogenizations, the prepared film is as thin as about 14 nm, and the diameter of the prepared liposome is about 150 nm. Through multiple high-pressure homogenizations, the diameter of the liposome is reduced on the basis of ensuring the structural integrity of the liposome, which also fully shows that the structure of the film of the present invention is excellent in stability, thereby leading to an improvement in the structural stability of the liposome; the above structural characteristics are similar to those of intercellular lipids, and can achieve bionics as much as possible in terms of structure.

[0030] Meanwhile, through the detection of the expression levels of filaggrin, loricrin, aquaporin, and tight junction protein, it was proved that after adding n-hexane, the expression levels of related proteins can be further improved.

[0031] Through the above optimizations, it is possible to completely simulate intercellular lipids, achieving the purpose of high expression of barrier proteins and better repair of the skin barrier.

[0032] In some preferred embodiments of the present invention, the content of hydrogenated lecithin is 4.0 wt%, 4.1 wt%, 4.2 wt%, 4.3 wt%, 4.4 wt%, 4.5 wt%, 4.6 wt%, 4.7 wt%, 4.8 wt%, 4.9 wt%, 5.0 wt%, 5.1 wt%, 5.2 wt%, 5.3 wt%, 5.4 wt%, 5.5 wt%, 5.6 wt%, 5.7 wt%, 5.8 wt%, 5.9 wt%, or 6.0 wt%;

[0033] In some preferred embodiments of the present invention, the content of cholesterol is 0.4 wt%, 0.5 wt%, or 0.6 wt%;

[0034] In some preferred embodiments of the present invention, the content of Limnanthes alba seed oil is 0.2 wt%, 0.3 wt%, or 0.4 wt%;

[0035] In some preferred embodiments of the present invention, the content of ceramide NP is 0.8 wt%, 0.9 wt%, 1.0 wt%, 1.1 wt%, or 1.2 wt%;

[0036] For every 100 g of liposome solution, the amount of organic solvent used is approximately around 40 - 100 ml, preferably 45 - 55 ml.

[0037] In some preferred embodiments of the present invention, the homogenization pressure can be 600, 650 bar, 700 bar, 750 bar, 800 bar;

[0038] The number of homogenization times can be 4, 5, 6, 7, 8 times;

[0039] In the above - mentioned method for preparing bionic sebum liposomes, the liposomes contain 28 - 32 wt% of butylene glycol.

[0040] Specifically, the content of each component in the liposomes is: 4 - 6 wt% of hydrogenated lecithin, 0.4 - 0.6 wt% of cholesterol, 0.2 - 0.4 wt% of Limnanthes alba seed oil, 0.8 - 1.2 wt% of ceramide NP, 28 - 32 wt% of butylene glycol, and the balance being water.

[0041] In the above - mentioned method for preparing bionic sebum liposomes, in step 2, in a rotary flask, the organic solvent is removed by rotary evaporation under reduced pressure to form a lipid film.

[0042] In the preliminary experiment of the present invention, it was found that the reduced - pressure parameters have no obvious effect on the product performance, and the reduced - pressure temperature is preferably controlled at 40 - 70 °C.

[0043] In the above - mentioned method for preparing bionic sebum liposomes, in step 3, the duration of hydration is not less than 40 min, preferably 40 - 80 min; in step 3, the optional hydration times are 40 min, 50 min, 60 min, 70 min or 80 min.

[0044] In the above - mentioned method for preparing bionic sebum liposomes, in step 4, the homogenization temperature is 10 - 50 °C.

[0045] In the preliminary experiment of the present invention, it was found that the homogenization temperature has a relatively slight effect on the product, and the optimal temperature is at room temperature or below.

[0046] Meanwhile, the present invention also discloses a kind of bionic sebum liposomes prepared by any of the above - mentioned methods.

[0047] Meanwhile, the present invention also discloses the use of the above - mentioned bionic sebum liposomes in the preparation of cosmetics.

[0048] Finally, the present invention also discloses a kind of cosmetics containing 0.1 - 10 wt% of the above - mentioned bionic sebum liposomes.

[0049] The above bionic sebum liposomes play a role in reconstructing and repairing the skin epidermal barrier in cosmetics, and improve the expression of filaggrin, loricrin, aquaporin 3, and claudin-1.

[0050] The cosmetics are products such as facial care, body care, hair care, etc.

[0051] Compared with the prior art, the present invention has the following beneficial effects:

[0052] The present invention realizes the bionics of the composition, proportion, and structure of liposomes through the optimization of the liposome formula, proportion, and selection of a suitable liposome preparation process;

[0053] First of all, in this scheme, the ratio of cholesterol to ceramide NP is close to 1:2, which is the main component of intercellular lipids. For free fatty acids, only Limnanthes alba seed oil is selected in the present invention. As the only plant oil present in this formula, Limnanthes alba seed oil has strong oxidation stability and is not easily deteriorated. It can enhance the skin barrier. Especially for liposomes prepared by the thin film hydration method, the function of Limnanthes alba seed oil in repairing the skin barrier is more significant; the selection of the above materials and proportions completely mimics intercellular lipids, realizing composition bionics and proportion bionics;

[0054] Secondly, the thin film hydration method is used to prepare liposomes. Compared with the microchannel method for preparing liposomes, the method of the present invention has unique advantages. Compared with the microchannel method, the preparation process of the thin film hydration method is simple and does not require an additional oily solvent as an oil phase medium to dissolve lipophilic solids. Excessive oily amorphous components will affect the formation of liposomes and will transform into oil-in-water emulsions rather than bilayer liposomes. The liposome structure obtained by the thin film hydration method is more complete. When combined with Limnanthes alba seed oil, it can significantly promote the expression of skin barrier-related proteins; through experimental verification, the thin film hydration method of the present invention can prepare liposomes with a wall thickness and diameter closer to those of intercellular lipids, realizing structure bionics.

[0055] For further demonstration and research on the scheme of the present invention, methanol, dichloromethane, and n-hexane are selected as the solvent phase. The three can improve the solubility of liposome raw materials. N-hexane can improve the tight arrangement of Limnanthes alba seed oil in the thin film. After the thin film is prepared under reduced pressure, through hydration and multiple high-pressure homogenizations, the prepared thin film is as thin as about 14 nm, and the diameter of the prepared liposomes is about 150 nm. Through multiple high-pressure homogenizations, on the basis of ensuring the structural integrity of the liposomes, the diameter of the liposomes is reduced, which also fully shows that the structure of the thin film of the present invention has excellent stability, thereby leading to an improvement in the structural stability of the liposomes; the above structural characteristics are similar to those of intercellular lipids, and can achieve bionics as much as possible from the structure.

[0056] Meanwhile, the detection of the expression levels of filaggrin, loricrin, aquaporin, and tight junction protein proved that the addition of n-hexane could further improve the expression of related proteins.

[0057] Through the above optimization, it is possible to fully simulate intercellular lipids, achieving the goal of high expression of barrier proteins and better repair of the skin barrier. Brief Description of the Drawings

[0058] Figure 1 It is the result graph of the dynamic light scattering (DLS) experiment;

[0059] Figure 2 It is the cryo-transmission electron micrograph of the biomimetic sebum liposome;

[0060] Figure 3 It is the SAXS curve graph of the biomimetic sebum liposomes of Example 1 and Comparative Example 1;

[0061] Figure 4 It is the immunofluorescence image of the barrier protein of the 3D skin model of the biomimetic sebum liposomes of Example 1 and Comparative Example 1. Detailed Embodiments

[0062] The technical solutions of the present invention will be further described below through specific embodiments. Those skilled in the art should understand that the described embodiments are only for helping to understand the present invention and should not be regarded as specific limitations to the present invention.

[0063] Reagents and Instruments

[0064] The reagents used in the experiments include: ceramide NP (purity > 98%, Shanghai Keqin Technology Co., Ltd.); cholesterol (analytical pure, Shanghai Macklin Biochemical Co., Ltd.); Limnanthes Alba (Mead) Benth. seed oil (Elementis Specialties); hydrogenated lecithin (purity > 90%, Lipoid Kosmetik AG); butanediol (purity > 98%, Daicel Corporation); methanol, dichloromethane, n-hexane, and chloroform are all analytical pure;

[0065] The main instruments used in the sample preparation process are: rotary evaporator (IKA Group, Germany) and high-pressure homogenizer (Antros Nano Technology (Suzhou) Co., Ltd.).

[0066] The First Part: Preparation of Liposomes by the Thin Film Hydration Method

[0067] Example 1

[0068] Step 1: Weigh 5 g of hydrogenated lecithin, 0.5 g of cholesterol, 0.3 g of Limnanthes alba seed oil, and 1 g of ceramide NP according to the target formula, place them in 50 ml of an organic solvent (a mixture of methanol and dichloromethane with a volume ratio of 3:2), and use ultrasonic treatment to promote dissolution.

[0069] Step 2: After complete dissolution, transfer the mixture to a rotary flask and evaporate the organic solvent under reduced pressure (pressure: starting from atmospheric pressure and finally reaching 50 mbar; temperature: 65 °C) to form a dry film.

[0070] Step 3: Weigh 30 g of butanediol and 63.2 g of water according to the formula table and add them to the rotary flask, and carry out the hydration process for 60 min.

[0071] Step 4: Use a high-pressure homogenizer to perform normal-temperature homogenization treatment on the hydrated solution at a pressure of 800 bar, and homogenize it cyclically 6 times to finally obtain biomimetic sebum liposomes.

[0072] Examples 2 - 9

[0073] The process steps are the same as those in Example 1, referring to Table 1 for the formula; referring to Table 2 for the process; specifically as follows:

[0074] Table 1 (weight unit: g)

[0075] Hydrogenated lecithin Cholesterol Limnanthes alba seed oil Ceramide NP Butylene glycol Water Example 2 4 0.6 0.2 1.2 28 To 100 Example 3 5.5 0.5 0.25 1.1 29 To 100 Example 4 6 0.4 0.4 0.8 31 To 100 Example 5 4.5 0.45 0.4 0.9 32 To 100 Example 6 5 0.5 0.3 1 30 To 100 Example 7 5 0.5 0.3 1 30 To 100 Example 8 5 0.5 0.3 1 30 To 100 Example 9 5 0.5 0.3 1 30 To 100

[0076] Table 2 (volume unit: ml; pressure unit: bar; duration unit: min)

[0077] Methanol Dichloromethane n-Hexane Chloroform Homogenization pressure Homogenization times Hydration time Example 2 30 15 0 0 600 8 40 Example 3 30 25 0 0 1000 4 80 Example 4 24 15 11 0 800 6 50 Example 5 22 14 14 0 700 7 60 Example 6 24 17 9 0 900 5 70 Example 7 24 15 0 11 800 6 50 Example 8 22 14 0 14 900 7 60 Example 9 24 17 0 9 1000 8 70

[0078] The second part: Preparation of liposomes using a continuous flow microchannel reactor

[0079] Comparative Example 1

[0080] Liposomes were prepared using a continuous flow microchannel reactor. This multi-channel reactor has two channels, model MF-4V, and the supplier is Microfluidic Technology (Changzhou) Co., Ltd.; the aqueous phase and the oil phase are introduced into each channel. Among them, hydrogenated lecithin is dispersed in water according to the formula table mass and used as the aqueous phase, and ceramide NP, cholesterol, and vegetable oil in the formula table mass are heated to 110 °C for dissolution and then mixed with butanediol and kept at a temperature above 100 °C as the oil phase.

[0081] The total flow rate is set to 10 ml / min, and the mass ratio of the aqueous phase and the oil phase fed is approximately 7:3. The liposome sample is collected at the outlet.

[0082] Liposomes were prepared by the above method;

[0083] Its formula is as shown in Table 3 below:

[0084] Table 3 Formula Table (weight unit: g)

[0085] Hydrogenated lecithin Cholesterol Limnanthes alba seed oil Ceramide NP Butylene glycol Water Comparative Example 1 5 0.5 0.3 1 30 63.2

[0086] Part III Performance Testing

[0087] Dynamic light scattering (DLS): Before testing, first dilute the liposomes with pure water to 1%, then place the diluted solution in the sample cell, and use a Malvern Zetasizer Advance instrument to measure the average particle size (in nanometers) and polydispersity index (PDI) of the liposomes.

[0088] Cryogenic transmission electron microscopy (cryo-TEM): The cryo-TEM experiment was completed on the scientific research platform of the Institute of Biophysics, Chinese Academy of Sciences. First, use a Gatan advanced plasma system (Model 950) to perform glow discharge treatment on the gold mesh (300 mesh 1.2 / 1.3GIG) to enhance its hydrophilicity. Then use a Vitrobot FEI TM to prepare a cryogenic TEM sample, with a loading volume of 3 μL of a 5% mass fraction OriginalSL TM sample solution. After rapid freezing, the sample liquid is transferred to liquid nitrogen for cooling. Finally, use a Gatan 626 cryo-transfer holder to transfer the sample to a Talos L120C 120 kV cryogenic transmission electron microscope for morphological observation.

[0089] Synchrotron radiation X-ray scattering: The small-angle X-ray scattering (SAXS) experiment was completed at the 19U2 Bio-X-ray Small-Angle Scattering Station of the Shanghai Synchrotron Radiation Facility. The X-ray wavelength (λ) is 0.103 nm. By adjusting the distance from the sample to the detector, the scattering vector q covers a certain range, where the scattering vector q = 4πsinθ / λ, and θ is the half-scattering angle. The experiment was carried out at room temperature. A static liquid cell encapsulated with mica flakes was used to load the liposome solution for testing. The optical path length of the liquid cell is 2 mm, and the exposure time for each scattering image is 1 second. By integrating the isotropic two-dimensional scattering pattern along the azimuth angle, a one-dimensional curve of the scattering intensity I(q) versus the scattering vector q is obtained. The final I(q) curve of the sample is obtained by averaging the data of 10 exposures, and the scattering signal of the solvent background is subtracted using Igor Pro Irena SAS software. The data was not corrected for absolute scattering intensity.

[0090] Barrier protein content detection based on a 3D epidermal model

[0091] ​A 3D epidermal model was stimulated with 0.1 wt.% sodium lauryl sulfate (SLS) to simulate barrier-damaged skin. The skin model was transferred to a 6-well plate (pre-added with 0.9 mL of EpiGrowth culture medium), and 25 μL of 0.1% SLS solution was added to each sample group and incubated for 30 min. Then, 12.5 μL of 5% liposome sample working solution was added to the surface of the model. After spreading evenly, it was placed in an incubator at 37°C and 5% CO2 for 24 h. After that, the residual test substances on the surface of the model were washed with sterile PBS solution, and the residual liquid inside and outside the model was wiped off with a sterile cotton swab. The model ring for tissue morphology detection was cut and removed, and fixed with 4% paraformaldehyde for 24 h. Immunofluorescence detection of barrier proteins and calculation of relative content were performed on the extracted model rings to evaluate the skin repair efficacy of each sample. The test results are shown in Table 4 and Figure 4 , Figure 4 is the immunofluorescence image of barrier proteins of the 3D skin model.

[0092] The sample of Example 1 after dilution was detected by dynamic light scattering (DLS) experiment. From the results of the dynamic light scattering particle size distribution, the average particle size of the liposome was 170.2 nm, and the PDI was 0.02, indicating good uniform dispersion.

[0093] It can be observed by cryo-transmission electron microscopy that the liposome structure prepared by the formulation and process of Example 1 is a large unilamellar liposome with only a single-layer membrane. The cryo-transmission electron microscopy shows that the particle size of the liposome is about 171 nm, which is consistent with the DLS particle size result (170.2 nm).

[0094] Comparing the SAXS data of the biomimetic sebum liposomes prepared with different process parameters, it can be seen that there is only one large broad peak in the scattering curves of Example 1 and Comparative Example 1, indicating that a single-layer liposome structure is formed, which is consistent with the results of cryo-transmission electron microscopy. The q value at the lowest point of the scattering intensity of Example 1 is higher than that of Comparative Example 1, indicating that the lipid layer thickness of Example 1 is thinner than that of Comparative Example 1; the subsequent broad peak is more obvious and has a higher intensity, indicating that the scattering contrast between the lipid layer and the solvent of Example 1 is large. This high scattering contrast may be due to the denser lipid layer, and the smaller full width at half maximum indicates that the lipid layer thickness is more uniform.

[0095] Table 4 Test Results

[0096]

[0097] Result Analysis:

[0098] 1. By comparing Examples 1-9 with Comparative Example 1, it can be seen that the biomimetic sebum liposomes composed of hydrogenated lecithin, ceramide NP, cholesterol, and Limnanthes alba seed oil prepared by the thin film hydration method are smaller in particle size and lipid layer thickness than those prepared by the microchannel method, indicating that different preparation processes will affect the structural parameters of the formed liposomes. At this ratio (4-6 wt% hydrogenated lecithin, 0.4-0.6 wt% cholesterol, 0.2-0.4 wt% Limnanthes alba seed oil, 0.8-1.2 wt% ceramide NP), the biomimetic sebum liposomes obtained by the thin film hydration method have a smaller particle size and a lipid layer thickness closer to the liquid crystal thickness of the intercellular lipids of the stratum corneum, with a structural biomimetic feature, so the expression level of barrier proteins is higher.

[0099] 2. By comparing Examples 1-3 with Examples 4-6, it can be seen that when n-hexane is added as an organic solvent, after evaporating the solvent to form a thin film and hydrating and homogenizing to obtain liposomes, the particle size and lipid layer thickness of the obtained liposomes are smaller than those without n-hexane, indicating that the structure of liposomes can be improved by screening appropriate solvent types. It is speculated that n-hexane, as a short-chain alkane, can promote the close and orderly arrangement between lipids during the formation of the thin film, thus obtaining a structure with a smaller lipid layer thickness. When the lipid arrangement is more compact and the thickness is closer to the thickness of the intercellular lipids of the skin, the expression level of barrier proteins in the sample group is higher, further indicating that the structural biomimicry can improve the skin repair effect.

[0100] 3. When other types of organic solvents are added, such as chloroform compared in Examples 7-9 of the present invention, the structure of the obtained liposomes and the expression level of barrier proteins have no obvious difference from those of Example 1, and even slightly worse. It shows that different solvents have different effects on the structure formation of liposomes, and better skin barrier repair effects can only be obtained when the lipid structure is more compact and the thickness is close to the liquid crystal thickness of the skin lipids;

[0101] From Examples 7-9, it can be seen that when the homogenization pressure and the number of times increase, the wall thickness, diameter, and protein expression are slightly improved, indicating that under the homogenization parameters of the present invention, significantly increasing the homogenization pressure and the number of times will not have a decisive impact on the product performance; however, if homogenization is not carried out, through the previous research of the present invention, it is found that its wall thickness and diameter will increase significantly.

[0102] Part Four Application Formulations

[0103] The formulation of the water-in-oil essence milk can refer to Table 5, the formulation of the oil-in-water cream can refer to Table 6, and the formulation of the essence water can refer to Table 7;

[0104] Table 5 Formulation of Water-in-Oil Essence Milk

[0105]

[0106]

[0107] Table 6 Oil-in-Water Cream Formula

[0108]

[0109]

[0110]

[0111] Table 7 Essence Water Formula

[0112]

[0113] The obtained bionic sebum liposomes have good solubility and can be applied to cosmetic products of different dosage forms.

[0114] The applicant declares that the process method of the present invention is illustrated by the above embodiments, but the present invention is not limited to the above process steps, which does not mean that the present invention must rely on the above process steps to be implemented. Those skilled in the art should understand that any improvement of the present invention, the equivalent substitution of the raw materials selected for the present invention, the addition of auxiliary components, the selection of specific methods, etc. all fall within the protection scope and the disclosure scope of the present invention.

Claims

1. A method for preparing a bionic sebum liposome, characterized in that: The steps include: Step 1: dissolving hydrogenated lecithin, cholesterol, meadowfoam seed oil, and ceramide NP in an organic solvent; Step 2: removing the organic solvent from the solution of step 1 to obtain a lipid film; Step 3: adding butanediol and water to hydrate the lipid film to form a crude liposome suspension; Step 4: homogenizing the crude liposome suspension at a pressure of 600-800 bar for 4-8 times to obtain liposomes; The liposome contains 4.5-6wt% hydrogenated lecithin, 0.4-0.5wt% cholesterol, 0.3-0.4wt% meadowfoam seed oil, and 0.8-1wt% ceramide NP; The organic solvent consists of methanol, dichloromethane and n-hexane; the volume ratio of the methanol, dichloromethane and n-hexane is 3:1.5-2.5:1-2, and the liposome contains 30-32wt% of butanediol.

2. The method for preparing biomimetic sebum liposomes according to claim 1, characterized in that: In the step 2, the organic solvent is removed by vacuum rotary evaporation in a rotating flask to form a lipid film.

3. The method for preparing the biomimetic sebum liposome according to claim 1, characterized in that: In step 3, the hydration time is not less than 40 minutes.

4. The method for preparing biomimetic sebum liposomes according to claim 1, characterized in that: In step 4, the homogenization temperature is 10-50°C.

5. A bionic sebum liposome, characterized in that: The method is prepared by any one of claims 1 to 4.

6. Use of the bionic sebum liposome as claimed in claim 5 in preparing cosmetics.

7. A cosmetic, characterized in that: Containing 0.1-10wt% of the biomimetic sebum liposome as claimed in claim 6.

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