A copper peptide - retinol complex solution and its preparation method and application

Abstract

The present invention relates to a copper peptide - retinol complex solution, a preparation method and an application thereof, belonging to the technical field of skin care active ingredients. The copper peptide - retinol complex solution of the present invention comprises copper peptide and retinol, wherein the retinol is wrapped inside an inclusion body formed by nanometer silk fibroin and a surfactant, and the copper peptide and the retinol coexist in an aqueous phase system without reacting. In the copper peptide - retinol complex solution of the present invention, an inclusion body with a more stable structure is prepared by using nanometer silk fibroin in combination with a surfactant. This stable inclusion body system can provide better protection for the retinol encapsulated therein. After the retinol forms a nano - inclusion body by using the inclusion body, it can be effectively protected in an aqueous phase environment, thereby avoiding its reaction with the copper peptide, realizing the long - term coexistence of the copper peptide and the retinol, and breaking through the compatibility taboos of efficacy skin care products.

Description

Technical Field

[0001] The present invention belongs to the technical field of skin care active ingredients, and particularly relates to a copper tripeptide-retinol complex solution, a preparation method thereof and an application thereof. Background Art

[0002] The aqueous-phase stable dispersion and stable compounding of active ingredients are the core and key to improving the efficacy of efficacy skin care products and the development of new efficacy skin care products, and have become a bottleneck problem in the development of efficacy skin care products. Copper tripeptide and retinol have multiple active effects and are extremely important multifunctional and high-value active ingredients in efficacy skin care products, and have been successfully applied to the development of various products. However, copper tripeptide has poor compatibility and interacts and reacts with various active ingredients, resulting in a reduction or even disappearance of its efficacy. Copper tripeptide and retinol are generally considered to be incompatibilities in efficacy skin care products, and different types of copper tripeptide and retinol raw materials on the existing market cannot be mixed in the same solution system without reacting. A compounding system containing both retinol and copper tripeptide has not been reported.

[0003] As an active ingredient insoluble in water, the emulsification system and liposome system are the main methods to improve its aqueous-phase dispersion. However, the above methods generally require heat treatment, and retinol is a temperature-sensitive active ingredient, and the existing emulsification and liposome systems encapsulating retinol cannot be directly compounded with copper tripeptide. How to improve the preparation method and simultaneously improve the protection of retinol to avoid reacting with copper tripeptide in the aqueous-phase system will provide a new solution for the compounding of various active ingredients and a new efficacy raw material for the development of efficacy skin care products. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the problem that copper tripeptide and retinol cannot coexist in the prior art.

[0005] To solve the above technical problem, the present invention provides a copper tripeptide-retinol complex solution, a preparation method thereof and an application thereof. By improving the encapsulation performance of retinol, the aqueous-phase mixing of copper tripeptide and retinol is realized, and retinol and copper tripeptide in the complex can be proportioned in any ratio, and has the advantages of being stable at room temperature without color change and reducing the irritation of the product.

[0006] The first object of the present invention is to provide a copper tripeptide-retinol complex solution, comprising copper tripeptide and retinol, wherein the retinol is encapsulated inside an inclusion body formed by nanometer silk fibroin and a surfactant, and the copper tripeptide and the retinol coexist and do not react and do not change color in an aqueous-phase system.

[0007] In one embodiment of the present invention, the β-sheet content of the nanofibrillar silk fibroin is higher than 30%; the width is 10 nm - 20 nm, the height is 1 nm - 5 nm, and the length is 20 nm - 2500 nm.

[0008] In one embodiment of the present invention, the hydrophobic chain of the surfactant is a non-isomeric hydrophobic chain. The surfactant can interact with the nanofibrillar silk fibroin. At a suitable temperature, the surfactant is transformed into a liquid state, and through stirring, it is uniformly dispersed and interacts with the nanofibrillar silk fibroin. After the interaction, the surfactant in the mixed system will not return to a solid state at room temperature, which is convenient for adding retinol at room temperature or low temperature to maintain the activity of retinol. After adding liquid retinol, through high-speed stirring or homogenization, a nano-inclusion body in which silk fibroin encapsulates retinol is formed by the interaction of nanofibrillar silk fibroin, surfactant, and retinol. It has excellent structural stability and can be stably dispersed in water. Retinol is fully encapsulated inside the silk fibroin, which can effectively prevent retinol from directly contacting with copper tripeptide in the aqueous solution and avoid its reaction with copper tripeptide, thus solving the problem that copper tripeptide and retinol cannot coexist in the aqueous phase system. The copper tripeptide and retinol inclusion body can be directly mixed in the aqueous phase and can exist stably for a long time, which is convenient for its compounding with other components and product development, and realizes the synergistic effect of retinol and copper tripeptide.

[0009] In one embodiment of the present invention, the surfactant is a non-ionic emulsifier.

[0010] In one embodiment of the present invention, the non-ionic emulsifier is selected from one or more of polyglycerol compounds, alkyl glycoside compounds, alkyl polyether compounds, glycerol fatty acid ester compounds, polyethylene glycol fatty acid ester compounds, polysorbate compounds, and sorbitan fatty acid esters. Non-ionic emulsifiers have the characteristics of poor foaming power and unstable foam. In practical applications, they are beneficial to the better formation of the carrier and have good mildness.

[0011] Further, the polyglycerol compounds are selected from one or more of polyglycerol-6 distearate, polyglycerol-6 stearate, polyglycerol-6 behenate, polyglycerol-3 cerotate, polyglycerol-10 laurate, and polyglycerol-3 methyl glucoside distearate.

[0012] Further, the alkyl glycoside compounds are selected from one or more of coco-glucoside, decyl glucoside, and lauryl glucoside.

[0013] Further, the alkyl polyether compounds are selected from one or more of PEG-6 caprylic / capric glycerides, PEG-7 glyceryl cocoate, cetearyl alcohol polyether-20, and cetyl PEG / PPG-10 / 1 dimethicone.

[0014] Furthermore, the glycerol fatty acid ester compounds are selected from one or more of lauroyl glycerol, stearoyl glycerol, and citric acid stearoyl glycerol.

[0015] Furthermore, the polyethylene glycol fatty acid ester compounds are selected from one or more of polyethylene glycol stearate, polyethylene glycol laurate, and polyethylene glycol oleate.

[0016] Furthermore, the polysorbate compounds are selected from one or more of polysorbate 20, polysorbate 60, and polysorbate 80.

[0017] In one embodiment of the present invention, the size of the inclusion body is 20 nm - 2000 nm.

[0018] The second object of the present invention is to provide a method for preparing the copper - peptide - retinol complex solution, comprising the following steps:

[0019] S1. Add water to the nanofibrillar silk fibroin and mix to obtain a nanofibrillar silk fibroin solution / gel with a concentration of 0.2 wt% - 5 wt%.

[0020] S2. Add a surfactant to the nanofibrillar silk fibroin solution / gel obtained in S1, heat and stir to obtain a mixed system; the addition amount of the surfactant is 0.2 wt% - 10 wt% of the nanofibrillar silk fibroin solution / gel.

[0021] S3. Cool down the mixed system obtained in S2, add retinol, and perform stirring or homogenization treatment to form a nano - inclusion body in which the nanofibrillar silk fibroin and the surfactant encapsulate retinol; the concentration of retinol in the nano - inclusion body is 0.1 wt% - 20 wt%.

[0022] S4. Dissolve the nano - inclusion body and copper - peptide obtained in S3 in an aqueous phase system to obtain the copper - peptide - retinol complex solution.

[0023] In one embodiment of the present invention, in S2, the heating temperature is 40°C - 100°C, so that the surfactant melts and turns into a liquid state, forming a liquid mixed system with water - oil phase separation, which is convenient for better interaction of different components.

[0024] In one embodiment of the present invention, in S2, the stirring speed is 40 rpm - 800 rpm, and the time is 1 min - 120 min. Through the stirring treatment, the nanofibrillar silk fibroin and the surfactant fully interact to form a uniform system without stratification and phase separation. Through the interaction, it is possible to avoid the surfactant from solidifying again at low temperature, which is beneficial to the addition of retinol at room temperature / low temperature.

[0025] In one embodiment of the present invention, in S3, the temperature reduction is to 4°C - 35°C. After the temperature reduction, the mixed system remains liquid, and the surfactant does not re-solidify. The temperature reduction can also avoid the destruction of the activity of retinol caused by the temperature when adding retinol.

[0026] In one embodiment of the present invention, in S3, the rotation speed of the stirring is 1000 rpm - 2800 rpm, and the time is 1 min - 120 min.

[0027] In one embodiment of the present invention, in S3, the rotation speed of the homogenization is 2800 rpm - 20000 rpm, and the time is 1 min - 120 min.

[0028] The technical solution of the present invention has the following advantages compared with the prior art:

[0029] (1) In the copper tripeptide - retinol complex solution of the present invention, a more stable inclusion body is prepared by using nano - silk fibroin combined with a surfactant. This stable inclusion body system can provide better protection for the retinol encapsulated therein. After the retinol forms nano - inclusion bodies by using the inclusion bodies, it can be effectively protected in the aqueous phase environment, thereby avoiding its reaction with copper tripeptide, realizing the long - term co - existence of copper tripeptide and retinol, and breaking through the compatibility taboos of efficacy skin care products.

[0030] (2) The copper tripeptide - retinol complex solution of the present invention encapsulates retinol with nano - silk fibroin having excellent biocompatibility, which can effectively reduce the irritation of retinol and has a better use experience. The ratio and concentration of retinol and copper tripeptide can be flexibly adjusted, increasing the flexibility of product formula design.

[0031] (3) The preparation method of the present invention has a simple process, is easy to control, is conducive to large - scale preparation, and has high industrialization potential. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to make the content of the present invention be more clearly understood, the following further details the present invention according to the specific embodiments of the present invention and in combination with the attached drawings, wherein:

[0033] Figure 1 It is the fluorescence microscope and SEM tests of the retinol nano - inclusion body of Test Example 1 of the present invention; wherein, a is the fluorescence microscope, and b is the SEM.

[0034] Figure 2 It is the infrared spectrum diagram of the retinol nano - inclusion body of Test Example 2 of the present invention.

[0035] Figure 3 It is the particle size result of the copper tripeptide - retinol complex solution of Test Example 3 of the present invention.

[0036] Figure 4 The infrared spectrogram of the copper peptide, retinol, and copper peptide-retinol complex solution in Test Example 4 of the present invention.

[0037] Figure 5 The macroscopic diagram of the copper peptide-retinol complex solution in Test Example 5 of the present invention. Detailed implementation manners

[0038] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, so that those skilled in the art can better understand the present invention and be able to implement it, but the specific embodiments cited are not intended to limit the present invention.

[0039] In the present invention, unless otherwise specified, the surfactant with the model of Emulium Mellifera MB used in the examples is purchased from Gattefosse France. Its main components are polyglyceryl-6 distearate, polyglyceryl-3 beeswaxate, jojoba esters, and cetyl alcohol. Among them, polyglyceryl-6 distearate and polyglyceryl-3 beeswaxate are emulsifiers, jojoba esters are humectants, and cetyl alcohol is a stabilizing emulsifier.

[0040] Example 1

[0041] A copper peptide-retinol complex solution, wherein the concentration of the copper peptide is 1 wt%, and the concentration of retinol is 2 wt%.

[0042] Its preparation specifically includes the following steps:

[0043] (1) Prepare a highly β-sheet content nanofibrillar silk fibroin (highly crystalline silk fibroin) with a width of 10 nm - 20 nm, a height of 1 nm - 5 nm, and a length of 2000 nm (β-sheet content is about between 45% - 55%) by the concentration-dilution-temperature cultivation method, add water and mix, and adjust the concentration to 2 wt% to obtain a highly β-sheet content nanofibrillar silk fibroin gel.

[0044] (2) Add the surfactant with the model of Emulium Mellifera MB to the highly β-sheet content nanofibrillar silk fibroin gel in an amount of 4 wt% to obtain a solid-liquid mixture.

[0045] (3) Under the condition that the stirring speed is 40 rpm, heat-treat the solid-liquid mixture with a magnetic heating stirrer, raise the temperature of the solid-liquid mixture to 80 °C to melt the surfactant and transform it into a water-oil phase mixture; then adjust the stirring speed to 200 rpm and stir the water-oil phase mixture for 15 min to fully mix and interact the nanofibrillar silk fibroin and the surfactant, and obtain a homogeneous liquid mixture without phase separation and layering.

[0046] (4) Cool the above liquid mixture to 20 °C. No surfactant precipitates. Subsequently, add liquid retinol in an amount of 8 wt%, and stir at a high speed of 1500 rpm for 20 min to obtain a nano-inclusion with a retinol concentration of 8 wt%.

[0047] (5) Dilute the nano-inclusion with water by 1 time to transform it into an aqueous solution of retinol with a concentration of 4 wt%. Dissolve blue copper peptide powder in water to prepare an aqueous solution with a concentration of 2 wt%. Subsequently, mix the retinol and blue copper peptide solutions in a volume ratio of 1:1 to obtain a blue copper peptide-retinol complex solution with a blue copper peptide concentration of 1 wt% and a retinol concentration of 2 wt%.

[0048] Example 2

[0049] A blue copper peptide-retinol complex solution, in which the concentration of blue copper peptide is 4 wt% and the concentration of retinol is 10 wt%;

[0050] Its preparation specifically includes the following steps:

[0051] (1) Prepare nanofibrillar silk fibroin with a high β-sheet content (β-sheet content is about between 45% and 55%) with a width of 10 nm - 20 nm, a height of 1 nm - 5 nm, and a length of 2000 nm by a concentration-dilution-temperature cultivation method. Mix with water, adjust the concentration to 3 wt%, and the nanofibers are in a gel state. Control the length of the nanofibrillar silk fibroin with a high β-sheet content by ultrasonic crushing technology. The ultrasonic power is 100 W and the ultrasonic time is 20 min. The gel turns into a solution to obtain a nanofibrillar silk fibroin solution with a length of 40 nm.

[0052] (2) Add polyglyceryl-10 laurate surfactant to the nanofibrillar silk fibroin solution with a high β-sheet content in an amount of 2 wt% to obtain a solid-liquid mixture.

[0053] (3) Under the condition of a stirring speed of 40 rpm, heat-treat the solid-liquid mixture with a magnetic heating stirrer, raise the temperature of the solid-liquid mixture to 85 °C to melt the surfactant and transform it into a mixture with a water-oil phase; then adjust the stirring speed to 100 rpm and stir the water-oil phase mixture for 60 min to fully mix and interact the nanofibrillar silk fibroin and the surfactant evenly to obtain a homogeneous liquid mixture without phase separation and layering.

[0054] (4) Cool the above liquid mixture to 30 °C. No surfactant precipitates. Subsequently, add liquid retinol in an amount of 10 wt%, and stir at a high speed of 1000 rpm for 30 min to obtain a nano-inclusion with a retinol concentration of 10 wt%.

[0055] (5) Add the copper tripeptide powder directly into the 10 wt% retinol nano-inclusion at a mass ratio of 4 wt%, stir and dissolve to obtain a copper tripeptide-retinol composite solution with a copper tripeptide concentration of 4 wt% and a retinol concentration of 10 wt%.

[0056] Example 3

[0057] A copper tripeptide-retinol composite solution, wherein the concentration of copper tripeptide is 0.2 wt% and the concentration of retinol is 0.2 wt%;

[0058] Its preparation specifically includes the following steps:

[0059] (1) Prepare highly β-sheet content nanofibrillar silk fibroin with a width of 10 nm - 20 nm, a height of 1 nm - 5 nm, and a length of 2000 nm (β-sheet content is about between 45% - 55%) by the concentration-dilution-temperature cultivation method, add water and mix, and adjust the concentration to 2 wt% to obtain a highly β-sheet content nanofibrillar silk fibroin gel.

[0060] (2) Add the surfactant of type Emulium Mellifera MB in an amount of 4 wt% to the highly β-sheet content nanofibrillar silk fibroin to obtain a solid-liquid mixture.

[0061] (3) Under the condition of a stirring speed of 40 rpm, heat-treat the solid-liquid mixture with a magnetic heating stirrer, raise the temperature of the solid-liquid mixture to 80 °C to melt the surfactant and transform it into a mixture with a water-oil phase; then adjust the stirring speed to 80 rpm and stir the water-oil phase mixture for 80 min to fully mix and interact the silk fibroin and the surfactant, and obtain a homogeneous liquid mixture without phase separation or stratification.

[0062] (4) Cool the above liquid mixture to 25 °C without precipitation of the surfactant, then add the liquid retinol in an amount of 6 wt%, and homogenize at a high speed of 10000 rpm for 10 min to obtain a nano-inclusion with a retinol concentration of 6 wt%.

[0063] (5) Dilute the retinol nano-inclusion 10 times with water to transform it into an aqueous retinol solution with a concentration of 0.6 wt%, dissolve the copper tripeptide powder in water to prepare an aqueous solution with a concentration of 0.6 wt%, then mix the retinol and copper tripeptide solutions according to a volume ratio of 1:1, and further dilute with water to obtain a copper tripeptide-retinol composite solution with a copper tripeptide concentration of 0.2 wt% and a retinol concentration of 0.2 wt%.

[0064] Comparative Example 1

[0065] (1) Prepare nanofibrillar silk protein with a high β-sheet content (β-sheet content is about 45%-55%) having a width of 10 nm - 20 nm, a height of 1 nm - 5 nm, and a length of 2000 nm by a concentration-dilution-temperature cultivation method. Add water and mix, and adjust the concentration to 2 wt% to obtain a nanofibrillar silk protein gel with a high β-sheet content.

[0066] (2) Add a surfactant of type Emulium Mellifera MB in an amount of 4 wt% to the nanofibrillar silk protein gel with a high β-sheet content to obtain a solid-liquid mixture.

[0067] (3) Under the condition of a stirring speed of 40 rpm, heat-treat the solid-liquid mixture with a magnetic heating stirrer to raise the temperature of the solid-liquid mixture to 80 °C to melt the surfactant and transform it into a mixture with a water-oil phase; then adjust the stirring speed to 200 rpm and stir the water-oil phase mixture for 15 min to fully mix and interact the nanofibrillar silk protein and the surfactant to obtain a homogeneous liquid mixture without phase separation or stratification.

[0068] (4) Cool the above liquid mixture to 20 °C without precipitation of the surfactant, then add liquid retinol in an amount of 8 wt% and stir at 400 rpm for 20 min to obtain a mixture with a retinol concentration of 8 wt%.

[0069] (5) Dilute the mixture with a retinol concentration of 8 wt% by adding water by 1 time to transform it into an aqueous retinol solution with a concentration of 4 wt%. Dissolve blue copper peptide powder in water to prepare an aqueous solution with a concentration of 2 wt%. Then mix the retinol and blue copper peptide solutions in a volume ratio of 1:1 to obtain a blue copper peptide-retinol complex solution with a blue copper peptide concentration of 1 wt% and a retinol concentration of 2 wt%.

[0070] Compared with Example 1, the blue copper peptide-retinol complex solution has poor stability. After standing for a period of time, retinol precipitates, crystallizes, and stratifies; the blue copper peptide reacts with retinol, and the solution changes from blue to green.

[0071] Test Example 1: Fluorescence microscopy and SEM tests

[0072] The microstructure of the retinol nanoinclusions formed in Example 1 was tested by fluorescence microscopy and SEM, and the results are as Figure 1 shown. Figure 1 The fluorescence microscopy results show that the retinol nanoinclusions can be evenly distributed in water and have a size of less than 1 μm. Subsequently, SEM was used to analyze its morphology in detail, and it was found that it is a nanoparticle with a size between 20 nm - 40 nm, indicating that retinol has been successfully encapsulated to form nanoinclusions.

[0073] Test Example 2: Infrared Spectrum

[0074] Verify whether the retinol in Example 1 is encapsulated in the silk fibroin inclusion body through infrared spectrum. The results are as Figure 2 shown. From Figure 2 the infrared spectrum, the characteristic peaks of high-crystalline silk fibroin and retinol can be seen, indicating that retinol has been successfully encapsulated by silk fibroin.

[0075] Test Example 3: Particle Size Test

[0076] After retinol prepared by other methods is mixed with copper tripeptide, a reaction will occur, resulting in color change and size change. Particle size test is a simple method to identify whether a reaction has occurred. The results are as Figure 3 shown. From Figure 3 it can be seen that after the retinol inclusion body in Example 1 is mixed with copper tripeptide, the particle size of the mixture is similar to that of retinol alone, indicating that retinol has not reacted with copper tripeptide.

[0077] Test Example 4: Infrared Test of Copper Tripeptide-Retinol Complex Solution

[0078] Usually, after copper tripeptide and retinol react, there may be changes in the characteristic peaks of the infrared spectrum. Perform an infrared test on the copper tripeptide-retinol complex solution prepared in Example 1. The results are as Figure 4 shown. From Figure 4 it can be seen that the infrared spectrum in the copper tripeptide-retinol complex solution can coincide with the characteristic spectra of copper tripeptide and retinol alone, indicating that no chemical change has occurred after mixing.

[0079] Test Example 5: Color Change

[0080] Color change is the most direct way to identify whether a reaction has occurred. In other systems, when retinol and copper tripeptide react, the color turns green. The macroscopic picture of the copper tripeptide-retinol complex solution in Example 1 is as Figure 5 shown. From Figure 5 it can be seen that the copper tripeptide-retinol complex solution in Example 1 still maintains the blue color of copper tripeptide, proving that it has not reacted with retinol.

[0081] Test Example 6: Stability Performance

[0082] After the copper tripeptide-retinol complex solution in Example 1 is placed at room temperature for 2 weeks, the complex solution still remains blue without reaction and stratification, proving that retinol has been successfully and completely encapsulated inside the nano-inclusion body and exists stably, thus avoiding its reaction with copper tripeptide and realizing the long-term coexistence of copper tripeptide and retinol.

[0083] Obviously, the above embodiments are merely examples for clear illustration and are not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to enumerate all implementation manners here. And the obvious changes or modifications derived therefrom still fall within the protection scope of the present invention.

Claims

1. A copper peptide - retinol complex solution, characterized in that, It includes copper tripeptide and retinol. The retinol is encapsulated inside an inclusion body formed by nanosized silk fibroin and a surfactant. The copper tripeptide and the retinol coexist in an aqueous phase system without reacting. The β-sheet content of the nanosized silk fibroin is higher than 30%. Its width is 10 nm - 20 nm, height is 1 nm - 5 nm, and length is 20 nm - 2500 nm. The surfactant is selected from one or more of polyglycerol compounds, alkyl glycoside compounds, alkyl polyether compounds, glycerol fatty acid ester compounds, polyethylene glycol fatty acid ester compounds, polysorbate compounds, and sorbitan fatty acid esters. The preparation method of the copper tripeptide - retinol composite solution includes the following steps. S1. Add water to the nanosized silk fibroin and mix to obtain a nanosized silk fibroin solution / gel with a concentration of 0.2 wt% - 5 wt%. S2. Add a surfactant to the nanosized silk fibroin solution / gel obtained in S1, heat and stir to obtain a mixed system. The addition amount of the surfactant is 0.2 wt% - 10 wt% of the nanosized silk fibroin solution / gel. The heating temperature is 40°C - 100°C. The stirring speed is 40 rpm - 800 rpm, and the time is 1 min - 120 min. S3. Cool down the mixed system obtained in S2, add retinol, and perform stirring or homogenization treatment to form a nanoinclusion body in which the nanosized silk fibroin and the surfactant encapsulate retinol. The concentration of retinol in the nanoinclusion body is 0.1 wt% - 20 wt%. The stirring speed is 1000 rpm - 2800 rpm, and the time is 1 min - 120 min. The homogenization speed is 2800 rpm - 20000 rpm, and the time is 1 min - 120 min. S4. Dissolve the nanoinclusion body obtained in S3 and copper tripeptide in an aqueous phase system to obtain the copper tripeptide - retinol composite solution.

2. The copper peptide - retinol complex solution according to claim 1, wherein The size of the inclusion body is 20 nm - 2000 nm.

3. The preparation method of the copper peptide - retinol complex solution according to claim 1, wherein In S3, the cooling is to cool down to 4°C - 35°C.

Images