High-content baicalin nanoemulsion as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of nano materials, and relates to a high-content baicalin nano-emulsion as well as a preparation method and application thereof. The high-content baicalin nano-emulsion is prepared from the following raw materials in percentage by weight. 1%-40% of a radix scutellariae extract; 1%-30% of an emulsifier; 1%-20% of a co-emulsifier; 1%-30% of grease; 0.1%-1% of a preservative; and the balance of water. The O / W baicalin nanoemulsion (with the baicalin content of 1%-15%) prepared by adopting a homogenization-ultrasonic process has the average particle size of 50 nm-100 nm, is good in stability and low in viscosity, is a brown-yellow semitransparent liquid in appearance, and successfully solves the problems of poor water solubility and low bioavailability of baicalin. Compared with the prior art, the high-content baicalin nanoemulsion prepared by the preparation method disclosed by the invention has the advantages that the solubility of the baicalin is remarkably improved, the high-concentration baicalin stably exists in the nanoemulsion, and the high-content baicalin nanoemulsion can be applied to cosmetics and also can be used in medicines for treating skin diseases.

Description

Technical Field

[0001] The invention belongs to the technical field of nano materials, and in particular relates to a high-content baicalin nanoemulsion and a preparation method and application thereof. Background Art

[0002] Scutellaria baicalensis is a traditional Chinese medicine with rich medicinal value. Its main effects include clearing away heat and dampness, purging fire and detoxifying, stopping bleeding, and calming the fetus. Baicalin, as the main active ingredient of Scutellaria baicalensis, is a glycoside compound composed of baicalein and glucuronic acid. It has good antioxidant, antibacterial, and ultraviolet absorption properties. It is often added to whitening cosmetics, acne treatment products, anti-allergic products, and sunscreen products. Therefore, baicalin is also widely used in the cosmetics field.

[0003] Baicalin has poor water solubility and fat solubility due to the presence of glycosyl bonds and internal hydrogen bonds in its molecular structure. This limits the solubility and bioavailability of baicalin in preparations, which in turn affects the efficacy of baicalin. In recent years, the formulation technologies used to improve the bioavailability of baicalin include nanotechnology, phospholipid complexes, solid dispersion technology, inclusion technology or self-emulsification technology. Among them, nanotechnology is to make baicalin into nanosuspensions, nanoemulsions, liposomes or lipid nanoparticles. Nanoemulsion is a colloidal dispersion system in which a liquid phase is dispersed in another immiscible phase in the form of droplets. It is a thermodynamically unstable system with a certain degree of kinetic stability. Its appearance is usually transparent or translucent, with a bluish glow, and a particle size between 10 and 100 nm. Compared with ordinary coarse emulsions, the nanoparticles in nanoemulsions have smaller intermolecular attraction due to their small particles, and are kinetically excellent in resisting particle aggregation and sedimentation. As a drug carrier, it can improve the solubility and stability of poorly soluble drugs.

[0004] At present, in the relevant research on baicalin nanoemulsion at home and abroad, the concentration of baicalin in the prepared nanoemulsion in the open document Development and invivo evaluation of baicalin-loaded W / O nanoemulsion for lymphatic absorption.[J].Pharmaceutical development and technology,2019,24(9):1155-1163 is 9.5 mg / mL; the content of baicalin in the prepared nanoemulsion in the open document Formulation optimization and the absorption mechanisms of nanoemulsion in improving baicalin oral exposure.[J].Drug development and industrial pharmacy,2018,44(2):266-275 is 9.8 mg / mL; the open document Optimization of Quality Attributes and Atomic Force Microscopy Imaging of Reconstituted Nanodroplets in Baicalin Loaded Self-Nanoemulsifying Formulations.[J].Pharmaceutics,2018,10(4):275-275. The content of baicalin in the prepared nanoemulsion is 2.5 mg / mL; the drug loading of baicalin nanoemulsion prepared in the public literature [Chen Liping, Li Xiaofang, He Chunrong, et al. Preparation of baicalin nanoemulsion using tea saponin as emulsifier and its pharmacodynamic study on promoting hair growth in mice [J]. Chinese Herbal Medicine,2023,54(02):561-568] is 1.1 mg / g.

[0005] Patent CN115607510B provides a high-concentration oleanolic acid nanoemulsion composition and a preparation method. The oleanolic acid nanoemulsion composition contains 0.5% to 2% oleanolic acid, 10% to 30% surfactant, 10% to 25% cosurfactant, 1% to 10% terpene-containing essential oil, 0.1% to 1% baicalin, 0.5% to 2% oleuropein, an appropriate amount of additives, and the balance is water. Add the cosurfactant and terpene-containing essential oil to container A, mix and stir evenly; then add the surfactant and mix; then add oleanolic acid and other active ingredients and stir until completely dissolved; add water and additives to container B to obtain an aqueous phase; slowly add the mixture in container A to the aqueous phase in container B while stirring to obtain a primary emulsion; high-speed shear emulsification, and the secondary emulsification is sufficient to obtain. It can be used in the preparation of cosmetics, in the preparation of drugs for treating skin diseases, and can be used for skin, hair and other care. However, the content of baicalin described in the patent is 0.1% to 1%, and the bioavailability of baicalin is still low. Summary of the invention

[0006] The purpose of the present invention is to provide a high-content baicalin nanoemulsion and its preparation method and application in order to overcome the problems existing in the above-mentioned prior art. The content of baicalin in the nanoemulsion prepared by the present invention ranges from 11.05 to 158.20 mg / mL (mass fraction is 1 to 15%), which significantly solves the problem of low bioavailability of baicalin caused by poor water solubility and fat solubility, and high-concentration baicalin exists stably in the nanoemulsion.

[0007] The purpose of the present invention can be achieved by the following technical solutions:

[0008] The present invention provides a high-content baicalin nanoemulsion, wherein the raw materials of the baicalin nanoemulsion include the following components in percentage by weight:

[0009]

[0010] The balance is water.

[0011] Furthermore, the preparation method of the scutellaria baicalensis extract comprises the following steps:

[0012] S1, crushing and sieving the scutellaria baicalensis slices to obtain scutellaria baicalensis powder, then dissolving the scutellaria baicalensis powder in water, stirring evenly and boiling in a boiling water bath, and then extracting baicalin by an ultrasound-flash extraction combined method, first ultrasound, then flash extraction, then cooling the flash-extracted solution to room temperature, centrifuging and collecting the supernatant, and filtering to obtain a baicalin extract;

[0013] S2, stirring and fully mixing the baicalin extract obtained in step S1 with anhydrous ethanol, keeping it still in the dark, collecting the supernatant by centrifugation, removing the ethanol in the supernatant by rotary evaporation, and then freeze-drying the supernatant to obtain the scutellaria baicalensis extract.

[0014] Furthermore, the emulsifier is selected from at least one of Tween 60, Tween 80, Span 80, polyglycerol-10 laurate, sodium lauryl sulfate, lecithin, Tween 20, polyoxyethylene castor oil, polyoxyethylene hydrogenated castor oil or glyceryl monostearate.

[0015] Furthermore, the auxiliary emulsifier is selected from at least one of anhydrous ethanol, 1,2-propylene glycol, PEG-400, glycerol, butylene glycol, and glycerol polyether-26.

[0016] Furthermore, the oil is selected from at least one of isopropyl myristate, caprylic capric triglyceride, C12-15 alcohol benzoate, jojoba seed oil, squalane, dicaprylyl carbonate, isohexadecane, white oil, silicone oil 200, isopropyl palmitate, and the like.

[0017] Furthermore, the preservative is selected from at least one of phenoxyethanol, methylparaben, ethylparaben, p-hydroxyacetophenone, 1,2-hexanediol and 1,2-pentanediol.

[0018] Furthermore, the remaining water is selected from any one of distilled water, purified water or deionized water.

[0019] Furthermore, the particle size of the baicalin nanoemulsion is 50nm to 100nm.

[0020] In another aspect, the present invention also provides a method for preparing any of the above-mentioned high-content baicalin nanoemulsions, comprising the following steps:

[0021] S1, mixing the formulated amount of oil and emulsifier, stirring evenly and heating to 60°C to 90°C to obtain phase A;

[0022] S2, mixing the scutellaria baicalensis extract, the co-emulsifier and water in the formula amount, stirring evenly and heating to 60° C. to 90° C. to obtain phase B;

[0023] S3, slowly adding the phase A to the phase B under homogenization conditions to obtain a mixture after homogenization, cooling the mixture to room temperature under stirring conditions, and then adding a formulated amount of preservatives to the mixture, stirring evenly to obtain a primary emulsion;

[0024] S4, ultrasonically emulsifying the primary emulsion, cooling it to room temperature after sufficient emulsification to obtain a high-content baicalin nanoemulsion, and storing it at room temperature away from light.

[0025] In a third aspect, the present invention also provides a use of any of the above-mentioned high-content baicalin nanoemulsions in the preparation of cosmetics, such as sunscreen, foundation, lotion, skin care essence, emulsion and other cosmetics to absorb ultraviolet rays and resist oxidation.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] (1) The present invention provides a high-content baicalin nanoemulsion and its preparation method and application: first, a baicalin extract is prepared by extraction and freeze-drying, wherein the baicalin content of the baicalin extract is 37.2%, and the baicalin is easily soluble in water. A high-concentration baicalin aqueous solution can be prepared, but the aqueous solution has poor stability and is prone to crystallization when left at room temperature, thus affecting its actual use; the nanoemulsion is a colloidal dispersion system composed of an aqueous phase, an oil phase, an emulsifier, and an emulsifier co-emulsifier, and the droplet size is usually 10 to 100 nm. The particle size of the droplets is extremely small, and its specific surface area is greatly increased, thereby increasing the contact area between the drug and the solvent and promoting the dissolution of the drug; and the surface of the nanoemulsion particles generally carries an electric charge, and these charges will generate electrostatic repulsion, which can prevent the droplets from agglomerating, thereby maintaining the stability of the nanoemulsion; therefore, the present invention prepares a high-content baicalin nanoemulsion (baicalin content is 1% to 15%) by adding the scutellaria extract as the baicalin raw material to the nanoemulsion formula, which significantly improves the solubility of baicalin. The average particle size of the nanoemulsion is 50 to 100nm, and its appearance is a brown-yellow translucent liquid with good stability and low viscosity; the high-content baicalin nanoemulsion of the present invention can be used in cosmetics and can also be used in drugs for treating skin diseases.

[0028] (2) The high-content baicalin nanoemulsion of the present invention is prepared according to the following raw materials in percentage by weight: 1% to 40% of scutellaria extract, 1% to 30% of emulsifier, 1% to 20% of co-emulsifier, 1% to 30% of oil, 0.1% to 1% of preservative, and the rest is deionized water; the scutellaria extract is added to the nanoemulsion formula as the baicalin raw material, and the O / W water-in-oil type baicalin nanoemulsion is prepared by homogenization-ultrasonic process, the average particle size of the baicalin nanoemulsion is between 50 and 100 nm, and the baicalin nanoemulsion has good antioxidant properties and ultraviolet absorption properties and is non-biologically irritating; it can be widely used in the field of cosmetics, such as lotions, skin care essences, lotions, hair growth lotions, hair care essences, etc.; it can also be used in drugs for improving or preventing hair loss, thinning hair, acne, seborrheic dermatitis, folliculitis, skin aging or other unhealthy skin conditions.

[0029] (3) The content of baicalin in the high-content baicalin nanoemulsion of the present invention ranges from 11.05 to 158.20 mg / mL (mass fraction of 1 to 15%), which is significantly better than the existing literature reports, and significantly solves the problem of low bioavailability of baicalin due to its poor water solubility and fat solubility, and high concentrations of baicalin exist stably in the nanoemulsion.

[0030] (4) Patent CN115607510B has a relatively strict restriction on the baicalin content, which is only within the range of 0.1-1%, while the baicalin content of the high-content baicalin nanoemulsion of the present invention is between 1% and 15%, providing a wider content range, which helps to more effectively solve the problem of low bioavailability of baicalin due to poor water solubility and fat solubility. In addition, the method for preparing the scutellaria baicalensis extract adopted by the present invention can obtain an extract with high baicalin content and good water solubility, while patent CN115607510B lacks such preparation advantages; in the preparation of nanoemulsion, the present invention uses ultrasonic crushing technology to prepare baicalin nanoemulsion with small particle size and good stability, which is not only convenient for storage and use, but also simpler to operate and has lower energy consumption than the high-pressure homogenization method in patent CN115607510B. In summary, the present invention has significant advantages in improving the bioavailability of baicalin, optimizing the preparation process and reducing production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 is the standard curve of baicalin;

[0032] Figure 2 This is the appearance of the high-content baicalin nanoemulsion prepared in Example 1;

[0033] Figure 3 This is a transmission electron microscopy image of the high-content baicalin nanoemulsion prepared in Example 1;

[0034] Figure 4 This is the particle size distribution diagram of the high-content baicalin nanoemulsion prepared in Example 1;

[0035] Figure 5 The effects of the high-content baicalin nanoemulsion prepared in Example 1 on the scavenging rates of DPPH and ABTS free radicals, wherein (a) is the effect of the high-content baicalin nanoemulsion prepared in Example 1 on the scavenging rate of DPPH free radicals, and (b) is the effect of the high-content baicalin nanoemulsion prepared in Example 1 on the scavenging rate of ABTS free radicals;

[0036] Figure 6 The ultraviolet absorption curve of the high-content baicalin nanoemulsion prepared in Example 1;

[0037] Figure 7 Figures 2 and 3 show the changes in vascular response after 0.25% saline, 0.1% NaOH solution and the high-content baicalin nanoemulsion prepared in Example 1 contacted CAM (chicken chorioallantoic membrane), wherein (a) shows the changes in vascular response after 0.25% saline contacted CAM, (b) shows the changes in vascular response after 0.1% NaOH solution contacted CAM, and (c) shows the changes in vascular response after the high-content baicalin nanoemulsion prepared in Example 1 contacted CAM. DETAILED DESCRIPTION

[0038] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0039] The present invention provides a high-content baicalin nanoemulsion, the particle size of which is 50nm to 100nm. The raw materials of the baicalin nanoemulsion include the following components in percentage by weight:

[0040]

[0041] The preparation method of the scutellaria baicalensis extract comprises the following steps:

[0042] 1) crushing and sieving the scutellaria baicalensis slices to obtain scutellaria baicalensis powder, then dissolving the scutellaria baicalensis powder in water, stirring evenly and boiling in a boiling water bath, and then extracting baicalin by an ultrasound-flash extraction combined method, first ultrasound, then flash extraction, then cooling the flash extraction solution to room temperature, centrifuging and collecting the supernatant, and filtering to obtain a baicalin extract;

[0043] 2) The baicalin extract obtained in step 1) is stirred and fully mixed with anhydrous ethanol, and after standing in the dark, the supernatant is collected by centrifugation, and then the ethanol in the supernatant is removed by rotary evaporation, and then the supernatant is freeze-dried to obtain the scutellaria baicalensis extract.

[0044] The emulsifier is selected from at least one of Tween 60, Tween 80, Span 80, polyglycerol-10 laurate, sodium lauryl sulfate, lecithin, Tween 20, polyoxyethylene castor oil, polyoxyethylene hydrogenated castor oil or glyceryl monostearate; the auxiliary emulsifier is selected from at least one of anhydrous ethanol, 1,2-propylene glycol, PEG-400, glycerol, butylene glycol, and glyceryl polyether-26; the oil is selected from at least one of isopropyl myristate, caprylic capric triglyceride, C12-15 alcohol benzoate, jojoba seed oil, squalane, dicaprylyl carbonate, isohexadecane, white oil, silicone oil 200, isopropyl palmitate, etc.; the preservative is selected from at least one of phenoxyethanol, methylparaben, ethylparaben, p-hydroxyacetophenone, 1,2-hexanediol, and 1,2-pentanediol; the balance of water is selected from any one of distilled water, purified water, or deionized water.

[0045] The high-content baicalin nanoemulsion is prepared by the following method:

[0046] S1, mixing the formulated amount of oil and emulsifier, stirring evenly and heating to 60°C to 90°C to obtain phase A;

[0047] S2, mixing the scutellaria baicalensis extract, the co-emulsifier and water in the formula amount, stirring evenly and heating to 60° C. to 90° C. to obtain phase B;

[0048] S3, slowly adding the phase A to the phase B under homogenization conditions to obtain a mixture after homogenization, cooling the mixture to room temperature under stirring conditions, and then adding a formulated amount of preservatives to the mixture, stirring evenly to obtain a primary emulsion;

[0049] S4, ultrasonically emulsifying the primary emulsion, cooling it to room temperature after sufficient emulsification to obtain a high-content baicalin nanoemulsion, and storing it at room temperature away from light.

[0050] The obtained high-content baicalin nanoemulsion can be used to prepare cosmetics, such as sunscreen, foundation, lotion, skin care essence, emulsion and other cosmetics, which can absorb ultraviolet rays and resist oxidation.

[0051] Unless otherwise specified, the reagents, methods, instruments and equipment used in the present invention are conventional reagents, methods, instruments and equipment in the art. Unless otherwise specified, the reagents and materials used in the following examples are commercially available.

[0052] Example 1

[0053] This embodiment provides a method for preparing a high-content baicalin nanoemulsion, and the specific steps are as follows:

[0054] ① The scutellaria baicalensis slices were crushed with a grinder and passed through a 75-mesh sieve to obtain scutellaria baicalensis powder. 30 g of scutellaria baicalensis powder was weighed and dissolved in 100 mL of deionized water, and stirred evenly to obtain an aqueous solution of scutellaria baicalensis. The aqueous solution of scutellaria baicalensis was then placed in a boiling water bath and boiled for 20 min. Baicalin was extracted using an ultrasonic-flash extraction combined extraction method, i.e., ultrasonication for 40 min, and then flash extraction was performed twice, each time for 120 s and at a rotation speed of 10000 rpm. The solution after flash extraction was cooled to room temperature, the supernatant was collected by centrifugation, and suction filtration was performed to remove the residue to obtain a baicalin extract.

[0055] ② The baicalin extract obtained in ① was transferred to a beaker and weighed, and 120 mL of anhydrous ethanol (to remove some polysaccharides and impurities) was added under stirring, stirred for 30 minutes, and allowed to stand for 12 hours in the dark, and then the supernatant was collected by centrifugation, and the anhydrous ethanol was removed by rotary evaporation using a rotary evaporator. The baicalin extract after treatment was freeze-dried to obtain the scutellaria baicalensis extract.

[0056] The scutellaria baicalensis extract obtained in ② was used to prepare a high-content baicalin nanoemulsion, and the preparation process was as follows:

[0057] ③ Use an electronic balance to accurately weigh 1.60 g of Tween 80 and 2.00 g of C12-15 alcohol benzoate as raw materials for phase A and place them in a beaker. Stir evenly and heat to 85°C to obtain phase A.

[0058] ④ Use an electronic balance to weigh 5.39 g of Scutellaria baicalensis extract, 1.20 g of 1,2-propylene glycol and 9.71 g of deionized water as phase B raw materials and place them in a beaker. Stir well and heat to 85°C to obtain phase B.

[0059] ⑤ Use a homogenizer to homogenize phase B, slowly add phase A obtained in ③ to phase B under homogenization conditions, and homogenize at 14000 rpm for 3 minutes. After homogenization, a mixture is obtained, and the mixture is cooled to room temperature under stirring, and then 0.10 g of phenoxyethanol is added to the mixture, and the primary emulsion is obtained after stirring.

[0060] ⑥ Place the primary emulsion obtained in ⑤ in an ultrasonic cell disruptor for ultrasonic emulsification for 3 minutes with a power of 300 W. After ultrasonication, cool to room temperature to obtain baicalin nanoemulsion, which is stored at room temperature away from light.

[0061] like Figure 1 As shown, Figure 1 The standard curve of baicalin is as follows: using anhydrous ethanol as solvent, scanning wavelength is 190nm~400nm, and determining the best UV absorption wavelength is 278nm. The linear regression equation is: y=60.6x+0.003, R 2 =0.9996, baicalin has a good linear relationship within 0.004mg / mL to 0.02mg / mL, which can be used to calculate the baicalin content. The baicalin content in the extract is calculated according to the following formula:

[0062]

[0063] Wherein: c is the concentration of the diluted sample (mg / mL); n is the dilution factor; v is the fixed volume of the extract (mL); m is the mass of the weighed baicalin extract (g).

[0064] like Figure 2 As shown, Figure 2 The appearance of the baicalin nanoemulsion prepared in this example is shown in FIG. The baicalin nanoemulsion was diluted and the absorbance value was measured by an ultraviolet spectrophotometer, and the concentration c was obtained by substituting it into the baicalin standard curve formula, and then the baicalin content in the baicalin nanoemulsion of this example was calculated to be 10.24% by the baicalin content calculation formula.

[0065] like Figure 3 As shown, Figure 3 This is a transmission electron microscope image of the baicalin nanoemulsion prepared in this example. It can be seen that the droplets of the baicalin nanoemulsion in this example are spherical and evenly distributed, and the particle edges are clear, indicating that its surface structure is smooth.

[0066] like Figure 4 As shown, Figure 4The particle size distribution diagram of the baicalin nanoemulsion prepared in this example (test method: dilute the sample 100 times with deionized water, take 2 mL of the diluted sample liquid into the sample pool, and use Brookhaven multi-angle particle size and high-sensitivity Zeta potential analyzer Omni to measure at 25°C and a scattering angle of 90°. The measurement result is the average of 3 parallel measurements). Figure 4 It can be seen that the particle size distribution of the nanoemulsion is narrow, indicating that the particles of the nanoemulsion have good uniformity and are evenly distributed; the average particle size of the baicalin nanoemulsion was measured to be 55.58±0.45nm, and the polydispersity index PDI was 0.103±0.046.

[0067] Table 1 Changes in baicalin content in baicalin nanoemulsion after three freeze-thaw cycles

[0068]

[0069] Table 1 shows the change in baicalin content of the baicalin nanoemulsion prepared in this example after three freeze-thaw cycles (placed at a low temperature of -18°C for 24 hours, and then restored at room temperature for 24 hours). As shown in Table 1, there is no obvious change in the baicalin content in the nanoemulsion after three freeze-thaw cycles, and no stratification, precipitation, flocculation, etc. occurs during the freeze-thaw process, indicating that the freeze-thaw stability of the baicalin nanoemulsion in this example is good.

[0070] Table 2 Changes in average particle size, polydispersity index (PDI) and baicalin content of baicalin nanoemulsion after storage for several days at different temperatures

[0071]

[0072]

[0073] Table 2 shows the average particle size, PDI and baicalin content of the baicalin nanoemulsion prepared in this example after storage at 4°C and 25°C for 1d, 3d, 7d, 14d and 30d. As shown in Table 2, the average particle size of the baicalin nanoemulsion at 4°C increased slightly, but the change was not obvious, while the particle size was significantly larger at room temperature 25°C, which may be due to the fact that at a higher temperature, the movement speed of the droplets is accelerated, which increases the probability of collision and polymerization between the droplets, thereby increasing the average particle size of the nanoemulsion. No stratification, precipitation, flocculation and the like occurred during storage at 4°C and 25°C for 30d, indicating that the storage stability of the baicalin nanoemulsion is good.

[0074] The baicalin nanoemulsion prepared in this example was subjected to the following performance tests (antioxidant performance, ultraviolet absorption performance, biofilm irritation):

[0075] (1) Antioxidant performance test

[0076] Experimental methods:

[0077] a. Determination of DPPH free radical scavenging rate

[0078] Preparation of DPPH solution: Weigh 3 mg of DPPH powder using a precision balance, dissolve in 60 mL of anhydrous ethanol, and dissolve and shake evenly by ultrasonic at room temperature. Take the solution to measure the absorbance, dilute it with anhydrous ethanol so that its absorbance value at 517 nm is between 1.2 and 1.3, and store it in a refrigerator at 4°C away from light;

[0079] Preparation of sample and VC solution: Weigh 30 mg of baicalin nanoemulsion and VC respectively, dissolve them in deionized water, and make up to volume in a 10 mL volumetric flask. Then dilute the sample and VC solution to different concentrations (0.01-0.30 mg / mL).

[0080] 1 mL of baicalin nanoemulsion solution of different concentrations was taken, and then 3 mL of DPPH solution was taken into a test tube, mixed evenly, and allowed to stand at room temperature in the dark for 30 min. The absorbance value was measured at 517 nm using an ultraviolet spectrophotometer. L -Ascorbic acid (VC) was used as a positive control, and the free radical scavenging rate was calculated as follows:

[0081]

[0082] Where: A0 is the absorbance value after the sample is replaced by anhydrous ethanol and mixed with DPPH solution; A i1 is the absorbance value after the reaction of samples / VC with different concentrations and DPPH solution; A j2 It is the absorbance value after anhydrous ethanol is used instead of DPPH solution and mixed with sample / VC solution of different concentrations.

[0083] b. Determination of ABTS free radical scavenging rate

[0084] Preparation of ABTS working solution: Use a precision balance to weigh 0.2030g of ABTS powder, add deionized water to the volume in a 50mL volumetric flask, shake thoroughly to obtain solution A, and store in a dark place. Weigh 0.0351g of potassium persulfate, add deionized water to the volume in a 50mL volumetric flask, shake thoroughly to obtain solution B, and store in a dark place. Mix solutions A and B in a volume ratio of 2.5:1 and store in a dark place for 12h. Take the solution to measure the absorbance, dilute it with deionized water so that the absorbance value at 734nm is between 0.7 and 1.0, and obtain the ABTS working solution;

[0085] Preparation of sample and VC solution: Weigh 30 mg of baicalin nanoemulsion and VC respectively, dissolve them in deionized water, and make up to volume in a 10 mL volumetric flask. Then dilute the sample and VC solution to different concentrations (0.005-0.16 mg / mL).

[0086] 1 mL of baicalin nanoemulsion solution of different concentrations was taken, and then 3 mL of ABTS solution was taken into a test tube, mixed evenly, and allowed to stand at room temperature in the dark for 30 min. The absorbance was measured at 734 nm using a UV spectrophotometer, and ascorbic acid (VC) was used as a positive control. The free radical scavenging rate was calculated using the same formula as DPPH.

[0087] The above steps were used to test the effects of baicalin nanoemulsion on the scavenging rates of DPPH and ABTS free radicals, and the scavenging rates of baicalin nanoemulsion and VC on DPPH and ABTS free radicals at the same concentration were compared. Figure 5 As shown, (a) is the effect of the high-content baicalin nanoemulsion prepared in this example on the scavenging rate of DPPH free radicals, and (b) is the effect of the high-content baicalin nanoemulsion prepared in this example on the scavenging rate of ABTS free radicals;

[0088] The scavenging rate of baicalin nanoemulsion for DPPH free radicals is positively correlated with the mass concentration. When the concentration increases to 0.28 mg / mL, the maximum scavenging rate for free radicals is 95.28%, which is close to the scavenging capacity of VC. As the mass concentration of baicalin nanoemulsion increases, the scavenging rate for ABTS free radicals also increases accordingly. When the concentration increases to 0.1 mg / mL, the maximum scavenging rate for free radicals is 94.51%, which is close to the scavenging capacity of VC. Studies have shown that baicalin achieves its antioxidant effect by releasing phenolic hydroxyl hydrogen atoms, and at the same time generates stable semiquinone free radicals, terminating the occurrence of free radical chain reactions, thereby achieving antioxidant effects. The baicalin nanoemulsion of this embodiment has a strong scavenging capacity for both DPPH and ABTS free radicals, indicating that it has good antioxidant properties.

[0089] (2) UV absorption performance test

[0090] Experimental method: Baicalin has absorption properties in the ultraviolet region. The absorption spectrum of the sample was studied using an ultraviolet spectrophotometer in the ultraviolet range of 190-400nm using a quartz cuvette with L=1cm. The sample was diluted 5000 times with deionized water before the test, and the sample absorption curve was recorded to examine the ultraviolet absorption performance of the baicalin nanoemulsion, and the ultraviolet absorption curves of the baicalin nanoemulsion and the blank nanoemulsion (without baicalin) were compared after being diluted 5000 times at 190-400nm.

[0091] Test results such as Figure 6 As shown, Figure 6The ultraviolet absorption curve of the high-content baicalin nanoemulsion prepared in this example; compared with the blank nanoemulsion, the nanoemulsion with baicalin added has better ultraviolet absorption, which is most obvious in the range of 250-350nm (mainly UVB). In addition, the baicalin nanoemulsion also has good absorption performance outside the range of 190-280nm (UVA). The results show that the baicalin nanoemulsion has good absorption and protection performance for both long-wave ultraviolet (UVA) and medium-wave ultraviolet (UVB).

[0092] (3) Biofilm irritation

[0093] Experimental method: Taking advantage of the clear, complete and transparent characteristics of the chorioallantoic membrane vascular system of the incubated chicken embryo in the middle stage, a certain amount of the test substance is brought into contact with the chicken embryo chorioallantoic membrane. After a period of action, the changes in the toxic effects (such as bleeding, coagulation and vascular lysis) on the chorioallantoic membrane are observed. These indicators reflect the changes in the morphological structure, color and permeability of the vascular network around the blood vessels, as well as the phenomena such as the denaturation of the chorioallantoic membrane protein and its degree of damage. Then a score is obtained comprehensively to evaluate the eye irritation of the test substance. Preparation of CAM (chicken embryo chorioallantoic membrane): First, conduct an egg inspection, mark the position of the air chamber on the eggshell surface with a marker, cut the air chamber with a cutting tool, gently peel off the marked eggshell part with tweezers to expose the white egg membrane, use a pipette to drip an appropriate amount of physiological saline to moisten the egg membrane, and carefully remove the inner membrane with tweezers. The endpoint evaluation method was adopted. The CAM was first photographed, and 0.3 mL of negative control (0.25% NaCl saline), positive control (0.1% NaOH solution) and baicalin nanoemulsion were directly applied to the CAM. After 3 minutes of action, the test substances on the CAM membrane were gently rinsed off with saline, and photos were taken to observe the changes in the CAM before and after the addition of the test substances, in order to evaluate the biomembrane irritation of baicalin nanoemulsion.

[0094] Test results such as Figure 7 As shown, Figure 7The diagrams of the changes in vascular response after 0.25% saline, 0.1% NaOH solution and the high-content baicalin nanoemulsion prepared in this embodiment contacted CAM (chicken embryo chorioallantoic membrane), wherein (a) is the diagram of the changes in vascular response after 0.25% saline contacted CAM, (b) is the diagram of the changes in vascular response after 0.1% NaOH solution contacted CAM, and (c) is the diagram of the changes in vascular response after the high-content baicalin nanoemulsion prepared in Example 1 contacted CAM. After 0.25% saline was used to act on CAM (chicken embryo chorioallantoic membrane) for 3 minutes, there was almost no change before and after; after 0.1% NaOH solution was used to act on CAM for 3 minutes, obvious bleeding, coagulation and vascular lysis occurred in CAM, indicating that 0.1% NaOH solution was highly irritating; after baicalin nanoemulsion was directly used for 3 minutes, there was no bleeding, coagulation and vascular lysis in CAM, indicating that the baicalin nanoemulsion of this embodiment was not irritating to biological membranes.

[0095] The above results show that the baicalin nanoemulsion of this example has good freeze-thaw stability, storage stability, antioxidant and UV protection, and has no biofilm irritation. It has broad application prospects in the field of cosmetics production, such as the production of sunscreen, liquid foundation, lotion, skin care essence, emulsion, etc.

[0096] Example 2

[0097] This embodiment provides a method for preparing a high-content baicalin nanoemulsion, and the specific steps are as follows:

[0098] ① The scutellaria baicalensis slices were crushed with a grinder and passed through a 75-mesh sieve to obtain scutellaria baicalensis powder. 30 g of scutellaria baicalensis powder was weighed and dissolved in 100 mL of deionized water, and stirred evenly to obtain an aqueous solution of scutellaria baicalensis. The aqueous solution of scutellaria baicalensis was then placed in a boiling water bath and boiled for 20 min. Baicalin was extracted using an ultrasonic-flash extraction combined extraction method, i.e., ultrasonication for 40 min, and then flash extraction was performed twice, each time for 120 s and at a rotation speed of 10000 rpm. The solution after flash extraction was cooled to room temperature, the supernatant was collected by centrifugation, and suction filtration was performed to remove the residue to obtain a baicalin extract.

[0099] ② The baicalin extract obtained in ① was transferred to a beaker and weighed, and 120 mL of anhydrous ethanol (to remove some polysaccharides and impurities) was added under stirring, stirred for 30 minutes, and allowed to stand for 12 hours in the dark, and then the supernatant was collected by centrifugation, and the anhydrous ethanol was removed by rotary evaporation using a rotary evaporator. The baicalin extract after treatment was freeze-dried to obtain the scutellaria baicalensis extract.

[0100] The scutellaria baicalensis extract obtained in ② was used to prepare a high-content baicalin nanoemulsion, and the preparation process was as follows:

[0101] ③ Use an electronic balance to accurately weigh 1.60 g of Tween 60 and 2.00 g of C12-15 alcohol benzoate as raw materials for phase A and place them in a beaker. Stir evenly and heat to 85°C to obtain phase A.

[0102] ④ Use an electronic balance to weigh 5.39 g of Scutellaria baicalensis extract, 1.20 g of 1,2-propylene glycol and 9.71 g of deionized water as phase B raw materials and place them in a beaker. Stir well and heat to 85°C to obtain phase B.

[0103] ⑤ Use a homogenizer to homogenize phase B, slowly add phase A obtained in ③ to phase B under homogenization conditions, and homogenize at 14000 rpm for 3 minutes. After homogenization, a mixture is obtained, and the mixture is cooled to room temperature under stirring, and then 0.10 g of phenoxyethanol is added to the mixture, and the primary emulsion is obtained after stirring.

[0104] ⑥ Place the primary emulsion obtained in ⑤ in an ultrasonic cell disruptor for ultrasonic emulsification for 3 minutes with a power of 300 W. After ultrasonication, cool to room temperature to obtain baicalin nanoemulsion, which is stored at room temperature away from light.

[0105] Example 3

[0106] This embodiment provides a method for preparing a high-content baicalin nanoemulsion, and the specific steps are as follows:

[0107] ① The scutellaria baicalensis slices were crushed with a grinder and passed through a 75-mesh sieve to obtain scutellaria baicalensis powder. 30 g of scutellaria baicalensis powder was weighed and dissolved in 100 mL of deionized water, and stirred evenly to obtain an aqueous solution of scutellaria baicalensis. The aqueous solution of scutellaria baicalensis was then placed in a boiling water bath and boiled for 20 min. Baicalin was extracted using an ultrasonic-flash extraction combined extraction method, i.e., ultrasonication for 40 min, and then flash extraction was performed twice, each time for 120 s and at a rotation speed of 10000 rpm. The solution after flash extraction was cooled to room temperature, the supernatant was collected by centrifugation, and suction filtration was performed to remove the residue to obtain a baicalin extract.

[0108] ② The baicalin extract obtained in ① was transferred to a beaker and weighed, and 120 mL of anhydrous ethanol (to remove some polysaccharides and impurities) was added under stirring, stirred for 30 minutes, and allowed to stand for 12 hours in the dark, and then the supernatant was collected by centrifugation, and the anhydrous ethanol was removed by rotary evaporation using a rotary evaporator. The baicalin extract after treatment was freeze-dried to obtain the scutellaria baicalensis extract.

[0109] The scutellaria baicalensis extract obtained in ② was used to prepare a high-content baicalin nanoemulsion, and the preparation process was as follows:

[0110] ③ Use an electronic balance to accurately weigh 1.60 g of polyglycerol-10 laurate and 2.00 g of C12-15 alcohol benzoate as raw materials for phase A and place them in a beaker. Stir well and heat to 85°C to obtain phase A.

[0111] ④ Use an electronic balance to weigh 5.39 g of Scutellaria baicalensis extract, 1.20 g of 1,2-propylene glycol and 9.71 g of deionized water as phase B raw materials and place them in a beaker. Stir well and heat to 85°C to obtain phase B.

[0112] ⑤ Use a homogenizer to homogenize phase B, slowly add phase A obtained in ③ to phase B under homogenization conditions, and homogenize at 14000 rpm for 3 minutes. After homogenization, a mixture is obtained, and the mixture is cooled to room temperature under stirring, and then 0.10 g of phenoxyethanol is added to the mixture, and the primary emulsion is obtained after stirring.

[0113] ⑥ Place the primary emulsion obtained in ⑤ in an ultrasonic cell disruptor for ultrasonic emulsification for 3 minutes with a power of 300 W. After ultrasonication, cool to room temperature to obtain baicalin nanoemulsion, which is stored at room temperature away from light.

[0114] Example 4

[0115] This embodiment provides a method for preparing a high-content baicalin nanoemulsion, and the specific steps are as follows:

[0116] ① The scutellaria baicalensis slices were crushed with a grinder and passed through a 75-mesh sieve to obtain scutellaria baicalensis powder. 30 g of scutellaria baicalensis powder was weighed and dissolved in 100 mL of deionized water, and stirred evenly to obtain an aqueous solution of scutellaria baicalensis. The aqueous solution of scutellaria baicalensis was then placed in a boiling water bath and boiled for 20 min. Baicalin was extracted using an ultrasonic-flash extraction combined extraction method, i.e., ultrasonication for 40 min, and then flash extraction was performed twice, each time for 120 s and at a rotation speed of 10000 rpm. The solution after flash extraction was cooled to room temperature, the supernatant was collected by centrifugation, and suction filtration was performed to remove the residue to obtain a baicalin extract.

[0117] ② The baicalin extract obtained in ① was transferred to a beaker and weighed, and 120 mL of anhydrous ethanol (to remove some polysaccharides and impurities) was added under stirring, stirred for 30 minutes, and allowed to stand for 12 hours in the dark, and then the supernatant was collected by centrifugation, and the anhydrous ethanol was removed by rotary evaporation using a rotary evaporator. The baicalin extract after treatment was freeze-dried to obtain the scutellaria baicalensis extract.

[0118] The scutellaria baicalensis extract obtained in ② was used to prepare a high-content baicalin nanoemulsion, and the preparation process was as follows:

[0119] ③ Use an electronic balance to accurately weigh 0.80 g of Tween 80 and 2.00 g of C12-15 alcohol benzoate as raw materials for phase A and place them in a beaker. Stir well and heat to 85°C to obtain phase A.

[0120] ④ Use an electronic balance to weigh 5.39 g of Scutellaria baicalensis extract, 1.20 g of 1,2-propylene glycol and 10.51 g of deionized water as phase B raw materials and place them in a beaker. Stir well and heat to 85°C to obtain phase B.

[0121] ⑤ Use a homogenizer to homogenize phase B, slowly add phase A obtained in ③ to phase B under homogenization conditions, and homogenize at 14000 rpm for 3 minutes. After homogenization, a mixture is obtained, and the mixture is cooled to room temperature under stirring, and then 0.10 g of phenoxyethanol is added to the mixture, and the primary emulsion is obtained after stirring.

[0122] ⑥ Place the primary emulsion obtained in ⑤ in an ultrasonic cell disruptor for ultrasonic emulsification for 3 minutes with a power of 300 W. After ultrasonication, cool to room temperature to obtain baicalin nanoemulsion, which is stored at room temperature away from light.

[0123] Example 5

[0124] This embodiment provides a method for preparing a high-content baicalin nanoemulsion, and the specific steps are as follows:

[0125] ① The scutellaria baicalensis slices were crushed with a grinder and passed through a 75-mesh sieve to obtain scutellaria baicalensis powder. 30 g of scutellaria baicalensis powder was weighed and dissolved in 100 mL of deionized water, and stirred evenly to obtain an aqueous solution of scutellaria baicalensis. The aqueous solution of scutellaria baicalensis was then placed in a boiling water bath and boiled for 20 min. Baicalin was extracted using an ultrasonic-flash extraction combined extraction method, i.e., ultrasonication for 40 min, and then flash extraction was performed twice, each time for 120 s and at a rotation speed of 10000 rpm. The solution after flash extraction was cooled to room temperature, the supernatant was collected by centrifugation, and suction filtration was performed to remove the residue to obtain a baicalin extract.

[0126] ② The baicalin extract obtained in ① was transferred to a beaker and weighed, and 120 mL of anhydrous ethanol (to remove some polysaccharides and impurities) was added under stirring, stirred for 30 minutes, and allowed to stand for 12 hours in the dark, and then the supernatant was collected by centrifugation, and the anhydrous ethanol was removed by rotary evaporation using a rotary evaporator. The baicalin extract after treatment was freeze-dried to obtain the scutellaria baicalensis extract.

[0127] The scutellaria baicalensis extract obtained in ② was used to prepare a high-content baicalin nanoemulsion, and the preparation process was as follows:

[0128] ③ Use an electronic balance to accurately weigh 2.00 g of Tween 80 and 2.00 g of C12-15 alcohol benzoate as raw materials for phase A and place them in a beaker. Stir evenly and heat to 85°C to obtain phase A.

[0129] ④ Use an electronic balance to weigh 5.39 g of Scutellaria baicalensis extract, 1.20 g of 1,2-propylene glycol and 9.31 g of deionized water as phase B raw materials and place them in a beaker. Stir well and heat to 85°C to obtain phase B.

[0130] ⑤ Use a homogenizer to homogenize phase B, slowly add phase A obtained in ③ to phase B under homogenization conditions, and homogenize at 14000 rpm for 3 minutes. After homogenization, a mixture is obtained, and the mixture is cooled to room temperature under stirring, and then 0.10 g of phenoxyethanol is added to the mixture, and the primary emulsion is obtained after stirring.

[0131] ⑥ Place the primary emulsion obtained in ⑤ in an ultrasonic cell disruptor for ultrasonic emulsification for 3 minutes with a power of 300 W. After ultrasonication, cool to room temperature to obtain baicalin nanoemulsion, which is stored at room temperature away from light.

[0132] Example 6

[0133] This embodiment provides a method for preparing a high-content baicalin nanoemulsion, and the specific steps are as follows:

[0134] ① The scutellaria baicalensis slices were crushed with a grinder and passed through a 75-mesh sieve to obtain scutellaria baicalensis powder. 30 g of scutellaria baicalensis powder was weighed and dissolved in 100 mL of deionized water, and stirred evenly to obtain an aqueous solution of scutellaria baicalensis. The aqueous solution of scutellaria baicalensis was then placed in a boiling water bath and boiled for 20 min. Baicalin was extracted using an ultrasonic-flash extraction combined extraction method, i.e., ultrasonication for 40 min, and then flash extraction was performed twice, each time for 120 s and at a rotation speed of 10000 rpm. The solution after flash extraction was cooled to room temperature, the supernatant was collected by centrifugation, and suction filtration was performed to remove the residue to obtain a baicalin extract.

[0135] ② The baicalin extract obtained in ① was transferred to a beaker and weighed, and 120 mL of anhydrous ethanol (to remove some polysaccharides and impurities) was added under stirring, stirred for 30 minutes, and allowed to stand for 12 hours in the dark, and then the supernatant was collected by centrifugation, and the anhydrous ethanol was removed by rotary evaporation using a rotary evaporator. The baicalin extract after treatment was freeze-dried to obtain the scutellaria baicalensis extract.

[0136] The scutellaria baicalensis extract obtained in ② was used to prepare a high-content baicalin nanoemulsion, and the preparation process was as follows:

[0137] ③ Use an electronic balance to accurately weigh 1.60 g of Tween 80 and 2.00 g of C12-15 alcohol benzoate as raw materials for phase A and place them in a beaker. Stir evenly and heat to 85°C to obtain phase A.

[0138] ④ Use an electronic balance to weigh 0.54 g of Scutellaria baicalensis extract, 1.20 g of 1,2-propylene glycol and 14.66 g of deionized water as phase B raw materials and place them in a beaker. Stir well and heat to 85°C to obtain phase B.

[0139] ⑤ Use a homogenizer to homogenize phase B, slowly add phase A obtained in ③ to phase B under homogenization conditions, and homogenize at 14000 rpm for 3 minutes. After homogenization, a mixture is obtained, and the mixture is cooled to room temperature under stirring, and then 0.10 g of phenoxyethanol is added to the mixture, and the primary emulsion is obtained after stirring.

[0140] ⑥ Place the primary emulsion obtained in ⑤ in an ultrasonic cell disruptor for ultrasonic emulsification for 3 minutes with a power of 300 W. After ultrasonication, cool to room temperature to obtain baicalin nanoemulsion, which is stored at room temperature away from light.

[0141] Example 7

[0142] This embodiment provides a method for preparing a high-content baicalin nanoemulsion, and the specific steps are as follows:

[0143] ① The scutellaria baicalensis slices were crushed with a grinder and passed through a 75-mesh sieve to obtain scutellaria baicalensis powder. 30 g of scutellaria baicalensis powder was weighed and dissolved in 100 mL of deionized water, and stirred evenly to obtain an aqueous solution of scutellaria baicalensis. The aqueous solution of scutellaria baicalensis was then placed in a boiling water bath and boiled for 20 min. Baicalin was extracted using an ultrasonic-flash extraction combined extraction method, i.e., ultrasonication for 40 min, and then flash extraction was performed twice, each time for 120 s and at a rotation speed of 10000 rpm. The solution after flash extraction was cooled to room temperature, the supernatant was collected by centrifugation, and suction filtration was performed to remove the residue to obtain a baicalin extract.

[0144] ② The baicalin extract obtained in ① was transferred to a beaker and weighed, and 120 mL of anhydrous ethanol (to remove some polysaccharides and impurities) was added under stirring, stirred for 30 minutes, and allowed to stand for 12 hours in the dark, and then the supernatant was collected by centrifugation, and the anhydrous ethanol was removed by rotary evaporation using a rotary evaporator. The baicalin extract after treatment was freeze-dried to obtain the scutellaria baicalensis extract.

[0145] The scutellaria baicalensis extract obtained in ② was used to prepare a high-content baicalin nanoemulsion, and the preparation process was as follows:

[0146] ③ Use an electronic balance to accurately weigh 1.60 g of Tween 80 and 2.00 g of C12-15 alcohol benzoate as raw materials for phase A and place them in a beaker. Stir evenly and heat to 85°C to obtain phase A.

[0147] ④ Use an electronic balance to weigh 8.02 g of Scutellaria baicalensis extract, 1.20 g of 1,2-propylene glycol and 7.08 g of deionized water as phase B raw materials and place them in a beaker. Stir well and heat to 85°C to obtain phase B.

[0148] ⑤ Use a homogenizer to homogenize phase B, slowly add phase A obtained in ③ to phase B under homogenization conditions, and homogenize at 14000 rpm for 3 minutes. After homogenization, a mixture is obtained, and the mixture is cooled to room temperature under stirring, and then 0.10 g of phenoxyethanol is added to the mixture, and the primary emulsion is obtained after stirring.

[0149] ⑥ Place the primary emulsion obtained in ⑤ in an ultrasonic cell disruptor for ultrasonic emulsification for 3 minutes with a power of 300 W. After ultrasonication, cool to room temperature to obtain baicalin nanoemulsion, which is stored at room temperature away from light.

[0150] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A high-content baicalin nanoemulsion, characterized in that: The raw materials of the baicalin nanoemulsion include the following components in percentage by weight: The balance is water.

2. The high-content baicalin nanoemulsion according to claim 1, characterized in that: The preparation method of the scutellaria baicalensis extract comprises the following steps: S1, crushing and sieving the scutellaria baicalensis slices to obtain scutellaria baicalensis powder, then dissolving the scutellaria baicalensis powder in water, stirring evenly and boiling in a boiling water bath, then extracting baicalin by an ultrasound-flash extraction combined method, cooling the flash-extracted solution to room temperature, collecting the supernatant by centrifugation, and filtering to obtain a baicalin extract; S2, stirring and fully mixing the baicalin extract obtained in step S1 with anhydrous ethanol, keeping it still in the dark, collecting the supernatant by centrifugation, removing the ethanol in the supernatant by rotary evaporation, and then freeze-drying the supernatant to obtain the scutellaria baicalensis extract.

3. The high-content baicalin nanoemulsion according to claim 1, characterized in that: The emulsifier is selected from at least one of Tween 60, Tween 80, Span 80, polyglycerol-10 laurate, sodium lauryl sulfate, lecithin, Tween 20, polyoxyethylene castor oil, polyoxyethylene hydrogenated castor oil or glyceryl monostearate.

4. The high-content baicalin nanoemulsion according to claim 1, characterized in that: The auxiliary emulsifier is selected from at least one of anhydrous ethanol, 1,2-propylene glycol, PEG-400, glycerol, butylene glycol, and glycerol polyether-26.

5. The high-content baicalin nanoemulsion according to claim 1, characterized in that: The oil is selected from at least one of isopropyl myristate, caprylic capric triglyceride, C12-15 alcohol benzoate, jojoba seed oil, squalane, dicaprylyl carbonate, isohexadecane, white oil, silicone oil 200, isopropyl palmitate and the like.

6. The high-content baicalin nanoemulsion according to claim 1, characterized in that: The preservative is selected from at least one of phenoxyethanol, methylparaben, ethylparaben, p-hydroxyacetophenone, 1,2-hexanediol and 1,2-pentanediol.

7. The high-content baicalin nanoemulsion according to claim 1, characterized in that: The remaining amount of water is selected from any one of distilled water, purified water or deionized water.

8. The high-content baicalin nanoemulsion according to claim 1, characterized in that: The particle size of the baicalin nanoemulsion is 50nm-100nm.

9. A method for preparing a high-content baicalin nanoemulsion according to any one of claims 1 to 8, characterized in that: The steps include: S1, mixing the formulated amount of oil and emulsifier, stirring evenly and heating to 60°C to 90°C to obtain phase A; S2, mixing the scutellaria baicalensis extract, the co-emulsifier and water in the formula amount, stirring evenly and heating to 60° C. to 90° C. to obtain phase B; S3, slowly adding the phase A to the phase B under homogenization conditions to obtain a mixture after homogenization, cooling the mixture to room temperature under stirring conditions, and then adding a formulated amount of preservatives to the mixture, stirring evenly to obtain a primary emulsion; S4, ultrasonically emulsifying the primary emulsion, cooling it to room temperature after sufficient emulsification to obtain a high-content baicalin nanoemulsion, and storing it at room temperature away from light.

10. Use of the high-content baicalin nanoemulsion according to any one of claims 1 to 8 in the preparation of cosmetics.

Images