Protection system for efficiently neutralizing inorganic sunscreen agent to generate free radicals and application thereof
阅读说明：本技术 一种高效中和无机防晒剂产生自由基的防护体系及其应用 (Protection system for efficiently neutralizing inorganic sunscreen agent to generate free radicals and application thereof ) 是由 左锦辉 刘炎 华陈兴 鲁楠 兰俐 于 2021-01-12 设计创作，主要内容包括：本发明公开一种高效中和无机防晒剂产生自由基的防护体系,测试方法及其应用。所述防护体系包括无机防晒剂(二氧化钛或氧化锌)和抗氧化剂的组合,能够高效地中和无机防晒剂在紫外光照下产生的自由基,实验经1,1-二苯基-2-三硝基苯肼(DPPH)法测定,自由基残余率不超过10％。(The invention discloses a protection system for efficiently neutralizing an inorganic sunscreen agent to generate free radicals, a test method and application thereof. The protective system comprises a combination of an inorganic sun-screening agent (titanium dioxide or zinc oxide) and an antioxidant, and can efficiently neutralize free radicals generated by the inorganic sun-screening agent under ultraviolet illumination, and the residual rate of the free radicals is not more than 10% as determined by a1, 1-diphenyl-2-trinitrophenylhydrazine (DPPH) method in an experiment.)
1. A protection system for neutralizing inorganic sunscreen agents to generate free radicals, wherein the protection system comprises an inorganic sunscreen agent and an antioxidant; the protective system is DPPH free radical clearance rate R measured by measuring the oxidation resistance of an antioxidant by a1, 1-diphenyl-2-trinitrophenylhydrazine (DPPH) method after an inorganic sun-screening agent is irradiated by ultraviolet lightbNot more than 10%.
2. The protection system of claim 1, wherein said protection system has a DPPH radical clearance RbNot more than 5%.
3. The protective system of claim 1, wherein the inorganic sunscreen agent is a nanopowder.
4. The protective system of claim 3 wherein said inorganic sunscreen agent is selected from titanium dioxide powder or zinc oxide powder.
5. The protective system of claim 4, wherein the titanium dioxide powder or zinc oxide powder has an average particle size of between 5 and 100 nanometers.
6. The protective system of claim 1, wherein the antioxidant comprises a fat soluble antioxidant, a water soluble antioxidant, or a alcohol soluble antioxidant.
7. The protective system of claim 1, wherein said antioxidants comprise (-) -epigallocatechin gallate, tocopherols, ferulic acid, emblic leafflower fruit extract, rosmarinic acid, and sodium metabisulfite.
8. The protective system of claim 1, wherein the weight ratio of inorganic sunscreen agent to antioxidant is in the range of 1:10-6-10-1In the meantime.
9. The protective system according to claim 4 or 7, wherein the weight ratio of the titanium dioxide powder to the antioxidant is 1:10-5-10-1To (c) to (d); the antioxidant is selected from tocopherol, Phyllanthus emblica fruit extract or sodium metabisulfite.
10. The protective system according to claim 4 or 7, wherein the weight ratio of the zinc oxide powder to the antioxidant is 1:10-6-10-1To (c) to (d); said antioxidant is selected from (-) -epigallocatechin gallate, an extract of the fruit of Emblica officinalis, rosmarinic acid or pyrogallolSodium sulfite.
11. A method of establishing a protective system according to any one of claims 1 to 10, characterized in that it comprises the steps of: mixing inorganic sunscreen agent with antioxidant, wherein the free radical generated by the inorganic sunscreen agent under ultraviolet irradiation is combined with antioxidant, and then the DPPH free radical clearance rate R obtained by measuring with 1, 1-diphenyl-2-trinitrophenylhydrazine (DPPH) methodbNot more than 10%.
12. The method of claim 11, wherein said DPPH radical clearance R isbThe method comprises the following steps:
(i) the inorganic sun-screening agent generates free radicals through ultraviolet irradiation;
(ii) (ii) combining an antioxidant with the free radicals produced in step (i);
(iii) after DPPH is added, the absorption value B1 is measured at 517 nm; or an absorption B2 at 517nm without DPPH;
(iv) calculation of DPPH radical scavenging Rate Rb＝[1-(B1-B2)/B0]100% of the total weight; wherein B0 is the absorbance at 517nm of a mixture of DPPH and the solvent used in steps (i) to (iii).
13. A method of establishing according to claim 11 or 12, characterized in that said method comprises the steps of:
(1) provides DPPH free radical clearance rate R which is obtained by measuring free radicals generated by titanium dioxide powder or zinc oxide powder through ultraviolet irradiation by a1, 1-diphenyl-2-trinitrophenylhydrazine (DPPH) methoda；
(2) DPPH free radical clearance rate R measured by 1, 1-diphenyl-2-trinitrophenylhydrazine (DPPH) method according to different antioxidantstObtaining a fitted curve according to R on the fitted curveaObtaining the theoretical concentration of each antioxidant;
(3) the DPPH free radical clearance rate is obtained by combining the free radical generated by the titanium dioxide powder or the zinc oxide powder through ultraviolet irradiation with an antioxidant and then measuring the free radical through a1, 1-diphenyl-2-trinitrophenylhydrazine (DPPH) methodRb；
(4) Dividing the theoretical concentration of the antioxidant obtained in the step (2) by the R in the step (3)bThe actual concentration of the antioxidant is not more than 10 percent, and the multiplying power of the antioxidant is obtained;
(5) the magnifications of the respective antioxidants were compared.
14. The method of claim 13, wherein the DPPH radical clearance R isaThe method comprises the following steps:
(a) irradiating titanium dioxide powder or zinc oxide powder by ultraviolet rays to generate free radicals;
(b) after DPPH was added, the absorbance A1 was measured at 517 nm; or the absorbance A2 was measured at 517nm only after the addition of a solvent for DPPH dissolution;
(c) calculation of DPPH radical scavenging Rate Ra＝[1-(A1-A2)/A0]100% of the total weight; wherein A0 is the absorbance at 517nm of DPPH mixed with the solvents used in steps (a) and (b).
15. The method of claim 13, wherein the amount of uv illumination radiation used in steps (1) and (3) is the same.
16. The method of claim 13, wherein the DPPH is used in the same amount in the reaction system in the step (1) and the step (3).
17. Use of a protective system according to any one of claims 1 to 10 in a cosmetic or toiletry product.
18. A cosmetic or care product characterized in that it comprises a protective system according to any one of claims 1 to 10 and a cosmetically acceptable carrier.
19. A process for the preparation of a cosmetic or toiletry product according to claim 18, characterized in that it comprises the steps of: mixing a cosmetically acceptable carrier with a protective system according to any one of claims 1 to 10 to give a cosmetic or care product according to claim 18.
Technical Field
The invention relates to the field of daily chemical industry, in particular to a protective system capable of neutralizing free radicals generated by an inorganic sun-screening agent, and an establishment method and application thereof.
Background
Uv light causes DNA damage to skin cells, broad spectrum sunscreen products refer to sunscreen products that protect against both UVB and UVA, and typically use SPF values to represent the ability to protect against UVB and PA values to represent the ability to protect against UVA. The commonly used inorganic sunscreens are mainly titanium dioxide and zinc oxide, the titanium dioxide mainly provides protection in the UVB band, and the zinc oxide mainly provides protection in the UVA band, however, both titanium dioxide and zinc oxide have photocatalytic ability, i.e. generate free radicals under the irradiation of ultraviolet light. Therefore, the sunscreen agents originally used for protecting the skin may bring certain oxidation pressure under the irradiation of light, accelerate the skin aging, and even destroy the ingredients in the cosmetic formula. In order to weaken free radicals generated by the inorganic sunscreen agent, the outer layer of the common inorganic sunscreen agent is subjected to coating treatment; different coating materials and processes reduce free radicals to different degrees, but complete elimination is difficult to achieve. Furthermore, the smaller the particles of inorganic sunscreen agent, the more time consuming, expensive and difficult it is to achieve a uniform surface coating. How to fully utilize the ultraviolet protection effect of the inorganic sunscreen agent and reduce the free radicals generated by photocatalysis is a difficult problem in the field.
The use of antioxidants in formulations is one way to protect the formulation or reduce skin damage. However, strong antioxidants are generally more unstable (react readily) and tend to discolor upon neutralization of free radicals, e.g., higher concentrations of tocopherol and ascorbic acid can themselves produce significant yellowing upon neutralization of free radicals, which makes the use of antioxidants in cosmetic formulations in sufficient amounts very challenging.
Therefore, there is a strong need in the art to provide a formulation and method for constructing the same that provides the correct antioxidant types and amounts for inorganic sunscreens.
Disclosure of Invention
The invention aims to provide a protective system which can effectively neutralize inorganic sunscreen agent to generate free radicals.
In a first aspect of the present invention there is provided a protection system for neutralizing inorganic sunscreen agents to generate free radicals, the protection system comprising an inorganic sunscreen agent and an antioxidant; the protective system is DPPH free radical clearance rate R measured by measuring the oxidation resistance of an antioxidant by a1, 1-diphenyl-2-trinitrophenylhydrazine (DPPH) method after an inorganic sun-screening agent is irradiated by ultraviolet lightbNot more than 10%.
In another embodiment, the DPPH radical clearance R of the protection systembNot more than 5%.
In another embodiment, the inorganic sunscreen agent is a nanopowder.
In another embodiment, the inorganic sunscreen agent is selected from titanium dioxide powder or zinc oxide powder.
In another embodiment, the titanium dioxide powder or zinc oxide powder has an average particle size of between 5 and 100 nanometers.
In another embodiment, the titanium dioxide powder is MT-10EX, MT-700Z from Tayca, Merck, GermanyT-AVO、T-EASY。
In another embodiment, the zinc oxide powder is HPA 30 available from Loxon (Luxon), MZX-508OTS available from Tayca, SAMT-Z1 available from Sanhao Suzhou (MIYOSHI).
In another embodiment, the antioxidant comprises a fat soluble antioxidant, a water soluble antioxidant, or a alcohol soluble antioxidant.
In another embodiment, the antioxidant comprises (-) -epigallocatechin gallate, tocopherol, ferulic acid, emblic extract, rosmarinic acid, and sodium metabisulfite.
In another embodiment, the weight ratio of the inorganic sunscreen agent to the antioxidant is in the range of 1:10-6-10-1In the meantime.
In another embodiment, the weight ratio of the titanium dioxide powder to the antioxidant is in the range of 1:10-5-10-1To (c) to (d); the antioxidant is selected from tocopherol, Phyllanthus emblica fruit extract or sodium metabisulfite.
In another embodiment, the weight ratio of MT-10EX from Tayca to sodium metabisulfite is in the range of 1: 2.5X 10-3-10-1To (c) to (d); preferably, the weight ratio of MT-10EX to sodium metabisulfite is 1: 2.5X 10-3-5×10-3In the meantime.
In another embodiment, the commercially available product is from Merck, GermanyThe weight ratio of T-AVO to tocopherol or the extract of the emblica officinalis is 1:10-5-10-1To (c) to (d); preferably, the first and second liquid crystal films are made of a polymer,the weight ratio of T-AVO to tocopherol or the extract of the emblica officinalis is 1: 2.5X 10-5-10-4In the meantime.
In another embodiment, the commercially available product is from Merck, GermanyThe weight ratio of T-EASY to tocopherol is 1: 5X10-5-10-1To (c) to (d); or the weight ratio of the sodium pyrosulfite to the sodium pyrosulfite is 1: 500-1-10-1To (c) to (d); preferably, the first and second liquid crystal films are made of a polymer,the weight ratio of T-EASY to tocopherol is 1: 5X10-5-5×10-4To (c) to (d); or the weight ratio of the sodium pyrosulfite to the sodium pyrosulfite is 1:10-3-5×10-3In the meantime.
In another embodiment, the weight ratio of MT-700Z from Tayca to sodium metabisulfite is in the range of 1:10-4-10-1To (c) to (d); or the weight ratio of the extract to the emblic leafflower fruit extract is 1:10-5-10-1To (c) to (d); preferably, the weight ratio of MT-700Z to sodium metabisulfite is in the range of 1: 2.5X 10-4-10-3To (c) to (d); or the weight ratio of the extract to the emblic leafflower fruit extract is 1:10-5-10-4In the meantime.
In another embodiment, the weight ratio of the zinc oxide powder to the antioxidant is in the range of 1:10-6-10-1To (c) to (d); the antioxidant is selected from (-) -epigallocatechin gallate, fructus Phyllanthi extract, rosmarinic acid or sodium pyrosulfite.
In another embodiment, the weight ratio of HPA 30, available from dewon (Luxon), to (-) -epigallocatechin gallate is in the range of 1: 5X10-6-10-1To (c) to (d); or the weight ratio of the extract to the emblic leafflower fruit extract is 1:10-4-10-1To (c) to (d); or the weight ratio of the sodium pyrosulfite to the sodium pyrosulfite is 1:10-3-10-1To (c) to (d); preferably, the weight ratio of HPA 30 to (-) -epigallocatechin gallate is in the range of 1: 5X10-6-5×10-5To (c) to (d); or the weight ratio of the extract to the emblic leafflower fruit extract is 1:10-4-10-3To (c) to (d); or the weight ratio of the sodium pyrosulfite to the sodium pyrosulfite is 1:10-3-5×10-3In the meantime.
In another embodiment, the weight ratio of MZX-508OTS from Tayca to (-) -epigallocatechin gallate is in the range of 1:10-6-10-1To (c) to (d); or the weight ratio of the extract to the emblic leafflower fruit extract is 1:10-4-10-1To (c) to (d); or the weight ratio of the rosmarinic acid to the rosmarinic acid is 1:10-5-10-1To (c) to (d); preferably, the weight ratio of MZX-508OTS to (-) -epigallocatechin gallate is from 1:10-6-10-5To (c) to (d); or the weight ratio of the extract to the emblic leafflower fruit extract is 1:10-4-5×10-4To (c) to (d); or the weight ratio of the rosmarinic acid to the rosmarinic acid is 1:10-5-10-4In the meantime.
In another embodiment, the weight ratio of SAMT-Z1 to sodium metabisulfite available from suzhou san hao (MIYOSHI) is in the range of 1: 5X10-6-10-1To (c) to (d); preferably, the weight ratio of SAMT-Z1 to sodium metabisulfite is in the range of 1: 5X10-6-10-5In the meantime.
In a second aspect of the present invention, there is provided a method for establishing the protection system provided by the present invention as described above, the method comprising the steps of: mixing inorganic sunscreen agent with antioxidant, wherein the free radical generated by the inorganic sunscreen agent under ultraviolet irradiation is combined with antioxidant, and then the DPPH free radical clearance rate R obtained by measuring with 1, 1-diphenyl-2-trinitrophenylhydrazine (DPPH) methodbNot more than 10%.
In another embodiment, the DPPH radical clearance rate RbThe method comprises the following steps:
(i) the inorganic sun-screening agent generates free radicals through ultraviolet irradiation;
(ii) (ii) combining an antioxidant with the free radicals produced in step (i);
(iii) after DPPH is added, the absorption value B1 is measured at 517 nm; or an absorption B2 at 517nm without DPPH; and
(iv) calculation of DPPH radical scavenging Rate Rb＝[1-(B1-B2)/B0]100% of the total weight; wherein B0 is the absorbance at 517nm of a mixture of DPPH and the solvent used in steps (i) to (iii).
In another embodiment, the method comprises the steps of:
(1) provides DPPH free radical clearance rate R which is obtained by measuring free radicals generated by titanium dioxide powder or zinc oxide powder through ultraviolet irradiation by a1, 1-diphenyl-2-trinitrophenylhydrazine (DPPH) methoda；
(2) DPPH free radical clearance rate R measured by 1, 1-diphenyl-2-trinitrophenylhydrazine (DPPH) method according to different antioxidantstObtaining a fitted curve according to R on the fitted curveaObtaining the theoretical concentration of each antioxidant;
(3) the DPPH free radical clearance rate R is obtained by combining free radicals generated by titanium dioxide powder or zinc oxide powder through ultraviolet irradiation with an antioxidant and then measuring the free radicals through a1, 1-diphenyl-2-trinitrophenylhydrazine (DPPH) methodb；
(4) Subjecting the product obtained in step (2)Theoretical concentration of antioxidant divided by step (3) RbThe actual concentration of the antioxidant is not more than 10 percent, and the multiplying power of the antioxidant is obtained; and
(5) the magnifications of the respective antioxidants were compared.
In another embodiment, the DPPH radical clearance rate RaThe method comprises the following steps:
(a) irradiating titanium dioxide powder or zinc oxide powder by ultraviolet rays to generate free radicals;
(b) after DPPH was added, the absorbance A1 was measured at 517 nm; or the absorbance A2 was measured at 517nm only after the addition of a solvent for DPPH dissolution;
(c) calculation of DPPH radical scavenging Rate Ra＝[1-(A1-A2)/A0]100% of the total weight; wherein A0 is the absorbance at 517nm of DPPH mixed with the solvents used in steps (a) and (b).
In another embodiment, step (1) and step (3) use the same amount of ultraviolet illumination radiation.
In another embodiment, the amount of DPPH used in the reaction system in step (1) and step (3) is the same.
In a third aspect of the invention there is provided the use of a protective system as described above in a cosmetic or toiletry product.
In a fourth aspect of the present invention, there is provided a cosmetic or care product comprising a protective system as provided by the present invention as described above and a cosmetically acceptable carrier.
In a fifth aspect of the present invention, there is provided a process for the preparation of a cosmetic or toiletry product as hereinbefore described provided by the present invention, the process comprising the steps of: the cosmetically acceptable carrier is mixed with the protective system provided by the present invention as described above to give the cosmetic or care product provided by the present invention as described above.
Accordingly, the invention provides a formula with proper antioxidant variety and dosage in inorganic sunscreen and a construction method thereof.
Drawings
FIG. 1 is an exponential fit curve of DPPH radical scavenging rates for 6 antioxidants obtained in the examples; wherein the content of the first and second substances,
a is related to (-) -epigallocatechin gallate(EGCG)B for alpha-tocopherol (VE), C for ferulic acid, D for the extract of the fruit of Phyllanthus emblica (Phyllanthus emblica)(Emblica)E for rosmarinic acid, F for sodium metabisulfite;
x represents the antioxidant concentration (wt%) and Y represents DPPH radical scavenging rate.
FIG. 2 is a DPPH radical scavenging curve obtained by neutralizing the radicals generated by MT-10EX (titanium dioxide powder from Tayca) under UV light with antioxidants of different concentrations and then reacting with DPPH solution; wherein the content of the first and second substances,
a for EGCG, B for alpha-tocopherol (VE), C for ferulic acid, D for Emblica, E for rosmarinic acid, F for sodium metabisulfite;
the abscissa represents the antioxidant concentration (wt%) and the ordinate represents the DPPH radical scavenging rate.
FIG. 3 isA DPPH free radical scavenging rate curve is obtained by carrying out neutralization reaction on free radicals generated by T-AVO (titanium dioxide powder purchased from Merck company of Germany) and antioxidants with different concentrations under the irradiation of UV light and then reacting the free radicals with DPPH solution; wherein the content of the first and second substances,
a for EGCG, B for alpha-tocopherol (VE), C for ferulic acid, D for Emblica, E for rosmarinic acid, F for sodium metabisulfite;
the abscissa represents the antioxidant concentration (wt%) and the ordinate represents the DPPH radical scavenging rate.
FIG. 4 isThe scavenging rate curve of DPPH free radical is obtained by carrying out neutralization reaction on free radical generated by T-EASY (titanium dioxide powder purchased from Merck company, Germany) under UV illumination and antioxidant with different concentrations and then reacting with DPPH solution; wherein the content of the first and second substances,
a for EGCG, B for alpha-tocopherol (VE), C for ferulic acid, D for Emblica, E for rosmarinic acid, F for sodium metabisulfite;
the abscissa represents the antioxidant concentration (wt%) and the ordinate represents the DPPH radical scavenging rate.
FIG. 5 is a graph showing DPPH radical scavenging rate obtained by neutralizing free radicals generated from MT-700Z (titanium dioxide powder available from Tayca) with antioxidants of different concentrations after exposure to UV light, and reacting with DPPH solution; wherein the content of the first and second substances,
a for EGCG, B for alpha-tocopherol (VE), C for ferulic acid, D for Emblica, E for rosmarinic acid, F for sodium metabisulfite;
the abscissa represents the antioxidant concentration (wt%) and the ordinate represents the DPPH radical scavenging rate.
FIG. 6 is a DPPH radical scavenging curve obtained by neutralizing HPA 30 (zinc oxide powder available from Luxon) with antioxidants of different concentrations after radical generation under UV light irradiation, and then reacting with DPPH solution; wherein the content of the first and second substances,
a for EGCG, B for alpha-tocopherol (VE), C for ferulic acid, D for Emblica, E for rosmarinic acid, F for sodium metabisulfite;
the abscissa represents the antioxidant concentration (wt%) and the ordinate represents the DPPH radical scavenging rate.
FIG. 7 is a DPPH radical scavenging curve obtained by neutralizing MZX-508OTS (Zinc oxide powder from Tayca) with antioxidants of different concentrations after free radical generation under UV light irradiation, and then reacting with DPPH solution; wherein the content of the first and second substances,
a for EGCG, B for alpha-tocopherol (VE), C for ferulic acid, D for Emblica, E for rosmarinic acid, F for sodium metabisulfite;
the abscissa represents the antioxidant concentration (wt%) and the ordinate represents the DPPH radical scavenging rate.
FIG. 8 is a DPPH radical scavenging curve obtained by neutralization of free radicals generated by SAMT-Z1 (zinc oxide powder available from MIYOSHI) under UV light with antioxidants of various concentrations, followed by reaction with DPPH solution; wherein the content of the first and second substances,
a for EGCG, B for alpha-tocopherol (VE), C for ferulic acid, D for Emblica, E for rosmarinic acid, F for sodium metabisulfite;
the abscissa represents the antioxidant concentration (wt%) and the ordinate represents the DPPH radical scavenging rate.
Detailed Description
The inventors have conducted extensive systematic screening and testing to find that there is a poor and good match between inorganic sunscreen agents and antioxidants for the photocatalytic generation of free radicals in inorganic sunscreens, i.e., for a particular inorganic sunscreen agent, a strong antioxidant (e.g., a strong DPPH scavenging ability) is generally considered not to be the most suitable, but rather a weaker antioxidant (e.g., a relatively weak DPPH scavenging ability) is generally considered to be unexpectedly effective in neutralizing the free radicals generated thereby. On the basis of this, the present invention has been completed.
To make the features and effects of the present invention comprehensible to those skilled in the art, general description and definitions are made below with reference to terms and expressions mentioned in the specification and claims. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.
"DPPH" refers to 1, 1-diphenyl-2-trinitrophenylhydrazine (1-diphenyl-2-piperidinylhydrazine), a commonly used reagent for testing oxidation resistance (or free radical scavenging).
As used herein, the "1, 1-diphenyl-2-trinitrophenylhydrazine method" or "DPPH method" refers to a commonly used experimental method for assessing the ability of an antioxidant to scavenge free radicals. DPPH has strong absorption at 517nm, and the solution (70% ethanol aqueous solution) is dark purple, and after being combined with electrons provided by free radicals or antioxidants, the solution is colorless or gray yellow, and the fading degree is in quantitative relation with the amount of electrons provided by the free radicals and/or the antioxidants, so that the solution can be quantitatively analyzed by a spectrophotometer.
DPPH is a free radical which can be neutralized by free radicals generated after the titanium dioxide or zinc oxide is irradiated by ultraviolet rays, and can also be reacted by electrons provided by an antioxidant, and both the reactions can shift the color absorption peak of DPPH to cause color change.
As used herein, the term "cosmetically acceptable carrier" refers to a carrier that allows a cosmetic or personal care product to be applied, including various excipients and diluents, which are not themselves essential active ingredients, and which do not have undue toxicity after application. Suitable carriers are well known to those of ordinary skill in the art. A sufficient discussion of cosmetically acceptable excipients can be found in the cosmetic hygiene specifications 2015 edition. Such carriers may include humectants, emulsifiers, thickeners, chelating agents, emollients, and the like in the composition. Such as, but not limited to, butylene glycol, glycerin, betaine, sodium hyaluronate, propylene glycol, glyceryl stearate/PEG-100 stearate, glyceryl stearate, xanthan gum, hydroxyethyl cellulose, carbomer, EDTA-2Na, isocetyl palmitate, isooctyl palmitate, cetostearyl alcohol, dimethicone, and the like.
As used herein, "room temperature" means 15-40 deg.C, preferably 20-30 deg.C.
As used herein, "inorganic sunscreen" refers to a type of sunscreen that is distinguished from chemical sunscreens, and belongs to the class of physical sunscreens, primarily titanium dioxide, zinc oxide, and titanium dioxide-mica, which are used on the skin to provide protection against ultraviolet light.
In one embodiment of the present invention, the inorganic sunscreen agent is titanium dioxide powder (or called nano titanium dioxide) or zinc oxide powder (or called nano zinc oxide); the average particle size of the titanium dioxide powder is 5-100nm, such as, but not limited to, 10-80nm, 20-25nm, and the like; the average particle size of the zinc oxide powder is 20-100nm, such as, but not limited to, 25-35nm, 30-60nm, and the like.
Although numerical ranges and parameters setting forth the broad scope of the invention are approximate, the values set forth in the specific examples are presented as precisely as possible. Any numerical value, however, inherently contains certain standard deviations found in their respective testing measurements. As used herein, "about" generally means that the actual value is within plus or minus 10%, 5%, 1%, or 0.5% of a particular value or range. Alternatively, the term "about" means that the actual value falls within the acceptable standard error of the mean, as considered by those skilled in the art. Except in the experimental examples, or where otherwise expressly indicated, it is to be understood that all ranges, amounts, values and percentages herein used (e.g., to describe amounts of materials, length of time, temperature, operating conditions, quantitative ratios, and the like) are to be modified by the word "about". Accordingly, unless indicated to the contrary, the numerical parameters set forth in the specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained. At the very least, these numerical parameters are to be understood as meaning the number of significant digits recited and the number resulting from applying ordinary carry notation.
All features defined herein as numerical ranges or percentage ranges, such as values, amounts, levels and concentrations, are for brevity and convenience only. Accordingly, the description of numerical ranges or percentage ranges should be considered to cover and specifically disclose all possible subranges and individual numerical values (including integers and fractions) within the range.
Unless defined otherwise herein, the scientific and technical terms used herein have the same meaning as is commonly understood and used by one of ordinary skill in the art. Furthermore, as used herein, the singular tense of a noun, unless otherwise conflicting with context, encompasses the plural form of that noun; the use of plural nouns also covers the singular form of such nouns.
The invention provides a protection system for neutralizing inorganic sunscreen agents to generate free radicals, wherein the protection system comprises nanoscale inorganic sunscreen agents and antioxidants; the antioxidants in the protection system were determined to match the corresponding inorganic sunscreen by DPPH assay.
The present invention can establish the protection system by mixing an inorganic sunscreen agent with an antioxidant, wherein the free radicals generated by ultraviolet irradiation of the inorganic sunscreen agent are combined with the antioxidant and then subjected to the combinationDPPH free radical clearance rate R obtained by DPPH methodbNot more than 10%; preferably not more than 5%.
In particular DPPH radical scavenging ratio RbThe method comprises the following steps:
firstly, the inorganic sun-screening agent generates free radicals through ultraviolet irradiation;
a second step of combining an antioxidant with the free radicals generated in the first step;
thirdly, adding DPPH and measuring an absorption value B1 at 517 nm; or directly measuring the absorption value B2 at 517nm without adding DPPH;
fourthly, calculating the DPPH free radical clearance rate Rb＝[1-(B1-B2)/B0]100% of the total weight; wherein B0 is the absorbance at 517nm of a mixture of DPPH and the solvent used in the first to third steps.
The present invention also allows for better or better matching of the inorganic sunscreen agent to the antioxidant in the protection system to be determined by the following method.
The method can comprise three parts:
the first part is to measure the generation of free radicals of the inorganic sun-screening agent under the irradiation of ultraviolet light and quantify the free radicals through a DPPH experiment;
a second part, measuring the DPPH removing capacity of different antioxidants;
and in the third part, screening the matching condition of the inorganic sunscreen agent and the antioxidant.
In one embodiment of the present invention, the first part is the DPPH radical clearance R obtained by measuring the radicals generated by the inorganic sunscreen agent through ultraviolet irradiation by a DPPH methoda。
In one embodiment of the present invention, the step of the first part may comprise:
firstly, enabling an inorganic sunscreen agent to generate free radicals under ultraviolet irradiation;
secondly, adding DPPH, and measuring the absorption value A1 at 517 nm; or adding a solvent (70% ethanol aqueous solution) for dissolving DPPH instead of DPPH, and measuring the absorption value A2 at 517 nm;
thirdly, obtaining the DPPH free radical clearance rate Ra＝[1-(A1-A2)/A0]100% calculation; wherein A0 is the absorbance at 517nm of DPPH mixed with the solvent used in the two steps.
In one embodiment of the invention, the second fraction is the DPPH radical scavenging ratio R determined by DPPH method on the basis of different antioxidantstObtaining a fitted curve on which R is obtained from the first partaThe theoretical concentration of each antioxidant was obtained.
In one embodiment of the present invention, the step of the second part may comprise:
in the first step, according to different concentrations of antioxidant and DPPH free radical clearance rate R corresponding to the antioxidanttPlotting the DPPH radical clearance R of the antioxidanttA curve;
secondly, calculating the theoretical concentration of antioxidant, namely R, required by the first part to completely remove the free radicals generated by the inorganic sunscreen agent after the ultraviolet irradiation according to the curveaThe corresponding concentration.
In one embodiment of the present invention, the DPPH radical clearance rate RtCan be obtained by the following steps: mixing antioxidant with certain concentration with DPPH-containing solution, and measuring the absorption value T1 at 517 nm; or mixing the antioxidant with solvent (70% ethanol aqueous solution) for dissolving DPPH, measuring the absorption value T2 at 517nm, and calculating DPPH free radical scavenging rate Rt＝[1-(T1-T2)/T0]100% calculation; where T0 is the absorbance at 517nm of a solution containing DPPH mixed with an antioxidant.
In one embodiment of the present invention, the third part is the DPPH radical clearance rate R measured by DPPH method after combining the free radicals generated by the inorganic sunscreen agent through ultraviolet irradiation with the antioxidantbAnd then dividing the theoretical concentration of antioxidant obtained in the second part by RbAnd when the concentration of the antioxidant does not exceed 10%, obtaining the multiplying power of the antioxidant, and finally comparing the multiplying power of the antioxidants to determine the matching condition of the inorganic sunscreen agent and the antioxidant.
In one embodiment of the present invention, the step of the third part may comprise:
firstly, enabling an inorganic sunscreen agent to generate free radicals under ultraviolet irradiation;
a second step of adding an antioxidant to combine with the radical generated in the first step;
thirdly, adding DPPH, and measuring the absorption value B1 at 517 nm; or an absorption B2 at 517nm without DPPH;
the fourth step, based on DPPH radical clearance rate Rb＝[1-(B1-B2)/B0]100% calculation; b0 is the absorbance at 517nm of a mixture of DPPH and the solvent used in the process system;
the fifth step, the theoretical concentration calculated by the second part is divided by the DPPH radical clearance R in the experimentbThe actual concentration of the antioxidant is not more than 10%, and the multiplying power of the antioxidant is obtained;
and sixthly, comparing the multiplying power of each antioxidant.
The method provided by the invention has the advantages that the ultraviolet light source, the light dose and the reaction time used in the first part and the third part are the same. For example, but not limited to, the amount of ultraviolet light irradiation is 7.2KJ, the antioxidant is added in the second step of the third step, the mixture is stirred and mixed, the reaction is carried out for 10 minutes, the DPPH is added in the third step, the mixture is stirred and mixed, and the absorption value B1 is measured after the reaction is carried out for 1 minute.
The DPPH radical scavenging rate data of each antioxidant obtained by ELISACalc software in the second part is subjected to exponential curve fitting, the theoretical concentration comes from the fitting curve, and the DPPH radical scavenging curve and IC of each antioxidant can be calculated through the fitting curve50The value is obtained. IC (integrated circuit)50The value refers to the antioxidant concentration at which DPPH free radical scavenging is 50%. Can pass through comparison IC50The value is evaluated to evaluate the strength of the antioxidant (or free radical scavenging) ability of various antioxidants. In general IC50The smaller, representing a greater ability to scavenge free radicals, theoretically better neutralizes the free radicals generated by the inorganic sunscreen agent.
In a preferred embodiment of the invention, the actual concentration of the third fraction is achieved byDPPH radical clearance rate R obtained after the first to the fifth stepbThe concentration of antioxidant does not exceed 5%.
In the sixth step of the third part, the larger the multiplying factor is, the better the matching of the corresponding antioxidant and the inorganic sunscreen agent is, that is, the more effective the inorganic sunscreen agent can neutralize the free radicals generated under the ultraviolet light.
The antioxidant which is obtained by the method and has the best matching property with a specific nano-scale inorganic sunscreen agent is used to form a protection system for neutralizing the nano-scale inorganic sunscreen agent to generate free radicals with the inorganic sunscreen agent, such as but not limited to a protection system of nano titanium dioxide and sodium metabisulfite, a protection system of nano titanium dioxide and Emblica, a protection system of nano titanium dioxide and tocopherol, a protection system of nano zinc oxide and EGCG, a protection system of nano zinc oxide and Emblica, a protection system of nano zinc oxide and sodium metabisulfite, a protection system of nano zinc oxide and rosmarinic acid and the like.
Tests prove that when the antioxidant is compounded with the inorganic sunscreen agent, the strength of the antioxidant is not absolute, and the antioxidant which is most suitable for the specific inorganic sunscreen agent is the best. Such as but not limited to,
MT-10EX of Tayca (titanium dioxide, aluminum hydroxide, isostearic acid) is suitable for being matched with sodium metabisulfite with weak DPPH scavenging, but not suitable for being matched with ferulic acid with strong DPPH scavenging;
of Merck, GermanyT-AVO is very suitable for Emblica with weak DPPH clearance and is not suitable for matching ferulic acid and rosmarinic acid with strong DPPH clearance;
of Merck, GermanyT-EASY is suitable for removing weak sodium metabisulfite with DPPH and is not suitable for being matched with EGCG with strong DPPH;
MT-700Z from Tayca (titanium dioxide, aluminum hydroxide, stearic acid) is well suited to Emblica and sodium metabisulfite, which have a weak DPPH scavenging potential, but not to ferulic and rosmarinic acids, which have a strong DPPH scavenging potential;
HPA 30 (zinc oxide, triethoxyoctylsilane) from Luxon (luxon) and sodium metabisulfite with a weak DPPH scavenging are suitable (the concentration actually used is only 14.7 of the theoretically estimated concentration-1) But not suitable for being matched with the tocopherol with stronger DPPH clearance (the actually used concentration is only 0.9 of the theoretically calculated concentration-1)；
After the MZX-508OTS (zinc oxide, triethoxyoctylsilane) of Tayca is compounded with EGCG or Emblica or rosmarinic acid, the free radical neutralization efficiency of the three antioxidants is 6-10 times of the theoretical value, the three combinations improve the use efficiency of the antioxidants, reduce the use concentration, and reduce the impact of the antioxidants on a formula stability system while providing the best protection; tayca's MZX-508OTS (Zinc oxide, triethoxyoctylsilane) is well suited with Emblica having a weak DPPH scavenging (the concentration actually used is only 10.1 of the theoretically estimated concentration)-1) The combination with the tocopherol with stronger DPPH clearance shows general (the actually used concentration is only 1.4 of the theoretically estimated concentration)-1)；
SAMT-Z1 (zinc oxide, dimethicone, myristic acid) from sanchi, suzhou (MIYOSHI) is well suited for rosmarinic acid, which has a lower DPPH clearance, than EGCG and ferulic acid, which have a higher DPPH clearance.
In one embodiment of the invention, the protective system may be chosen in particular from:
(1) MT-10 EX: sodium metabisulfite is 1: 2.5X 10-3-10-1，w/w；
(2)T-AVO: the tocopherol is 1:10-5-10-1，w/w，T-AVO: emblica is 1: 1x10-5-10-1,w/w；
(3)T-EASY: the tocopherol is 1: 5x10-5-10-1Or is orT-EASY: sodium metabisulfite is 1: 500-1-10-1,w/w；
(4) MT-700Z: sodium metabisulfite is 1:10-4-10-1MT-700Z: emblica is 1:10-5-10-1，w/w；
(5) HPA 30, (-) -epigallocatechin gallate (EGCG) is 1: 5x10-6-10-1W/w; HPA 30: emblica is 1:10-4-10-3W/w; HPA 30: sodium metabisulfite is 1:10-3-10-1，w/w；
(6) MZX-508OTS EGCG is 1:10-6-10-1W/w; MZX-508OTS: emblica is 1:10-4-10-1W/w; MZX-508OTS: rosmarinic acid 1:10-5-10-1W/w; or
(7) SAMT-Z1 sodium metabisulfite 1: 5x10-6-10-1，w/w。
The protective system for neutralizing the nano-scale inorganic sunscreen agent to generate free radicals can be used for preparing cosmetics or washing and protecting products. For example, but not limited to, the protective systems provided herein are combined with a cosmetically acceptable carrier to provide a variety of cosmetic or lotion products that can be applied to human skin, including, but not limited to, sun blocks, sun creams, and the like.
In one embodiment of the invention, the dispersion phase containing the nanoscale inorganic sunscreen agent is added to an oil phase formed by some cosmetically acceptable carriers, the mixture phase is obtained by stirring and homogenizing, then an aqueous phase formed by other cosmetically acceptable carriers is added to the mixture phase, and the mixture phase is emulsified to obtain the cosmetic or washing and protecting product which can be applied to human skin.
In some embodiments of the present invention, cosmetically acceptable carriers for forming the aqueous phase include, but are not limited to, glycerin, butylene glycol, water-soluble antioxidants, EDTA-2Na, citric acid, water, and the like.
In some embodiments of the present invention, cosmetically acceptable carriers for forming the oil phase include, but are not limited to, glyceryl stearate/PEG-100 stearate complex, isomeric hexadecanes, isooctyl palmitate, cetostearyl alcohol, dimethicone, petrolatum, shea butter, squalane, lecithin, ethylhexyl methoxycinnamate, ethyl diethylhydroxybenzoylbenzoate, and the like.
In some embodiments of the present invention, cosmetically acceptable carriers for forming the dispersed phase containing nanoscale inorganic sunscreen agents include, but are not limited to, cyclopentadimethylsiloxane, polymethylsilsesquioxane, polydimethylsiloxane, octylmethicone, phenyl trimethicone, trimethylsiloxysilicate, cyclopentadimethylsiloxane, C12-15 alcohol benzoate, talc, styrene/DVB crosspolymer, isododecane, ethanol, and the like.
The theory or mechanism described and disclosed herein, whether correct or incorrect, should not limit the scope of the present invention in any way, i.e., the present disclosure may be practiced without limitation to any particular theory or mechanism.
The features mentioned above with reference to the invention, or the features mentioned with reference to the embodiments, can be combined arbitrarily. All features disclosed in this specification may be combined in any combination, provided that there is no conflict between such features and the combination, and all possible combinations are to be considered within the scope of the present specification. Each feature disclosed in this specification may be replaced by an alternative feature serving the same, equivalent, or similar purpose. Thus, unless expressly stated otherwise, the features disclosed are merely generic examples of equivalent or similar features.
The main advantages of the invention are:
1. by finding out the matching effect between the inorganic sunscreen agent and the antioxidant, the use efficiency of the antioxidant can be improved, the use concentration can be reduced, and the impact of the antioxidant on a formula stability system can be reduced while the optimal protection is provided; for example, tocopherol, typically at a concentration of 0.2%, causes most formulations to yellow over time. In the invention, only tocopherol with extremely low concentration (such as 0.000025-0.0001%) can be used for well neutralizing free radicals generated by the inorganic sunscreen agent under ultraviolet light, thereby being beneficial to avoiding the problem of discoloration of the formula.
2. The present invention challenges the conventional view that the strongest antioxidant capacity is also the best. Tests prove that when the antioxidant is compounded with the inorganic sunscreen agent, the strength of the antioxidant is not absolute, and the antioxidant which is most suitable for the specific inorganic sunscreen agent is the best.
The invention will be further illustrated with reference to the following specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. The experimental procedures, in which specific conditions are not noted in the following examples, are generally carried out according to conventional conditions or according to conditions recommended by the manufacturers. All percentages, ratios, proportions, or parts are by weight unless otherwise specified. The weight volume percentage units in the present invention are well known to those skilled in the art and refer to, for example, the weight of solute in a 100 ml solution. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. In addition, any methods and materials similar or equivalent to those described herein can be used in the methods of the present invention. The preferred embodiments and materials described herein are intended to be exemplary only.
Experimental examples 1 to 7
Laboratory apparatus and device
6 common antioxidants tested in examples 1-7:
inorganic sunscreens referred to in examples 1 to 7:
MT-10EX is a titanium dioxide powder having a mean particle size distribution of 10nm, available from Tayca.
T-AVO is a titanium dioxide powder with an average particle size distribution of 20-25nm, available from Merck, Germany.
T-EASY is a titanium dioxide powder having an average particle size distribution of 20 to 25nm and available from Merck, Germany.
MT-700Z is a titanium dioxide powder having an average particle size distribution of 80nm, available from Tayca.
HPA 30 is a zinc oxide powder with average particle size of 30-60nm, and is available from Luxon.
MZX-508OTS is a zinc oxide powder having an average particle size distribution of 25nm available from Tayca.
SAMT-Z1 is a zinc oxide powder with an average particle size distribution of 35nm, available from Sanhao, Suzhou (MIYOSHI).
The experimental steps are as follows:
measuring the generation of free radicals of an inorganic sunscreen agent under the irradiation of ultraviolet light, and quantifying by a DPPH (double priming ph) experiment;
taking 5g of 6% inorganic sunscreen agent dispersion slurry (preparation method comprises weighing inorganic sunscreen agent according to 6% of main active ingredient of inorganic sunscreen agent, dispersing in propylene glycol, homogenizing at 4000r/min for 10min), placing in 30ml glass bottle, and irradiating with ultraviolet for 15 min; adding 5g of 0.016% DPPH solution (70% ethanol aqueous solution as solvent), magnetically stirring for 1min (1000Mot), centrifuging the reacted solution for 5min
(4000r/min), taking the supernatant and measuring the absorbance at 517nm to obtain A1.
The DPPH solution was replaced by an equal mass of 70% aqueous ethanol solution in the above procedure to obtain a 2.
A0 is formulated by the following equation: absorbance of A0 ═ 0.008% DPPH solution (5g propylene glycol +5g 0.016% DPPH solution)
Inorganic sunscreens generate free radicals under Ultraviolet (UV) light, according to DPPH radical clearance Ra＝[1-(A1-A2)/A0]100% calculation.
Second, measure the DPPH removing ability of different antioxidants
Since these 6 antioxidants are both water-soluble and oil-soluble, it is difficult to dissolve them with water, ethanol or propylene glycol alone, and it is necessary to find a solvent in which these antioxidants are well soluble, and after investigation, a mixed solvent (propylene glycol: 70% ethanol in water 1:2) can well dissolve 1% of the 6 antioxidants used in the present invention.
Preparing 0.016% DPPH solution (the concentration is 0.008% after dilution) by using a mixed solvent (propylene glycol: 70% ethanol aqueous solution is 1:2), mixing the DPPH solution with a series of antioxidant solutions with concentration gradients (prepared by using the mixed solvent), uniformly mixing the DPPH solution and the antioxidant solutions according to the ratio of 5g to 5g, magnetically stirring the mixture for 1min (1000Mot), standing the mixture for reaction for 30min in a dark place, and testing the absorbance at 517nm, wherein the absorbance is marked as T1;
absorbance of 5g of 0.016% DPPH solution +5g of mixed solution T0
Absorbance of the mixed solution of 5g antioxidant solution and 5g T2
DPPH radical scavenging Rate Rt＝[1-(T1-T2)/T0]*100％
The DPPH free radical scavenging rate data of each sample is subjected to exponential curve fitting by using ELISACalc software, and the DPPH free radical scavenging curves and ICs of 6 antioxidants are calculated50Values, as shown in the table below, are fitted to the graph shown in FIG. 1.
DPPH free radical IC50Clearing capability ordering: EGCG>Ferula asafoetidaAcid(s)>Rosmarinic acid>VE>Emblica>Sodium metabisulfite.
Thirdly, screening the optimal combination of inorganic sunscreen agent and antioxidant
Taking 5g of 6% inorganic sunscreen agent dispersion slurry (preparation method: according to the main active ingredient of the inorganic sunscreen agent being 6%, weighing the inorganic sunscreen agent, dispersing in propylene glycol, homogenizing at 4000r/min for 10min), placing in a 30ml glass bottle, irradiating with ultraviolet light with the same radiation amount as the first part for 15min, then adding 2.5g of antioxidant solution with certain concentration (solvent is 70% ethanol water solution), magnetically stirring for 10min (1000Mot), then adding 7.5g of 0.016% DPPH solution (solvent is 70% ethanol water solution), magnetically stirring for 1min (1000Mot), then taking the reacted solution, centrifuging for 5min (4000r/min), taking the supernatant, and measuring the absorbance at 517nm to obtain B1.
B1 ═ absorbance (5g of 6% inorganic sunscreen slurry +2.5g of antioxidant solution +7.5g of 0.016% DPPH solution)
Without DPPH added in the above procedure, B2:
b2 ═ absorbance (5g of 6% inorganic sunscreen syrup +2.5g of antioxidant solution +7.5g of 70% aqueous ethanol solution)
B0 is formulated by the following formula:
b0 ═ 0.008% DPPH solution (5g propylene glycol +2.5g 70% aqueous ethanol +7.5g 0.016% DPPH solution)
DPPH radical scavenging Rate Rb＝[1-(B1-B2)/B0]*100％
Investigating the matching of specific inorganic sunscreens with the respective antioxidants
The DPPH clearance data obtained by adding antioxidants of different types and concentrations to eliminate free radicals generated by inorganic sunscreens under ultraviolet irradiation and then reacting with DPPH solution are shown in FIGS. 2-8.
Consideration of the ratio of the minimum concentration of antioxidant to the theoretical concentration required to completely neutralize the free radicals generated by inorganic sunscreens
The ratio between the "complete neutralization" (DPPH clearance controlled within 5%) of the inorganic sunscreen to free radical generation, the minimum concentration required for each antioxidant, and the theoretical concentration of each antioxidant as calculated from its DPPH clearance curve is shown in the table below.
Remarking: IC (integrated circuit)XMeans the estimated concentration of free radicals generated by completely neutralizing a certain inorganic sunscreen agent
Fifthly, respectively matching with corresponding inorganic sunscreen agents
(I) antioxidant matching MT-10EX
MT-10EX is titanium dioxide powder, which is surface treated with aluminum hydroxide and isostearic acid to obtain particle diameter of 10nm, and free radicals generated by MT-10EX under ultraviolet irradiation are neutralized with sodium pyrosulfite to obtain concentration of 5.4 of the estimated concentration-1It can be seen that MT-10EX has good adaptability to sodium metabisulfite. The invention is proved by experiments that when the antioxidant is compounded with the inorganic sunscreen agent, the antioxidant with the strongest inoxidizability is the best, the antioxidant which is most suitable for the specific inorganic sunscreen agent is the best, the proper antioxidant, namely sodium metabisulfite, is selected to neutralize free radicals generated by MT-10EX due to illumination, the use efficiency of the oxidant is improved, the use concentration is reduced, and the impact of some strong antioxidants (such as tocopherol and ascorbic acid) on a formula stability system can be avoided or reduced while the optimal protection is provided.
(II) andT-AVO matched antioxidants
T-AVO is titanium dioxide powder, which is surface treated with silica and has average particle size distribution of 20-25nm, neutralizing with Emblica or tocopherolThe concentration of the free radicals generated by the T-AVO under the ultraviolet irradiation actually required is only 4.5 of the estimated concentration respectively-1，2.5-1It is shown thatT-AVO has good adaptability with Emblica and tocopherol. Experiments prove that when the inorganic sunscreen agent is compounded with the inorganic sunscreen agent, the free radicals generated by the inorganic sunscreen agent under ultraviolet irradiation can be completely neutralized only by using the tocopherol with extremely low addition amount; it was also found that Emblica was able to neutralize efficientlyThe free radicals generated by T-AVO under UV illumination, both of which facilitate the development of more efficient and stable formulations.
(III) andT-EASY matched antioxidants
T-EASY is a titanium dioxide powder, which is surface-treated with silica and cetyl phosphate with average particle size distribution of 20-25nm, and neutralized with sodium pyrosulfite or tocopherolThe concentration of the free radicals generated by T-EASY under UV illumination actually required is only 3.2 of the estimated concentration-1，3.4-1It is shown thatT-EASY has good adaptability with sodium pyrosulfite and tocopherol. The invention is proved by tests that when the sunscreen composition is compounded with inorganic sunscreen agent, the sunscreen composition can be prepared by only using very low addition amount of tocopherolCompletely neutralize free radicals generated by the inorganic sunscreen agent under ultraviolet illumination. At the same time, it was found that sodium metabisulfite can be efficiently neutralizedFree radicals generated by T-EASY under ultraviolet illumination are both convenient for developing more effective and stable formulations.
(IV) antioxidant matching MT-700Z
MT-700Z is a titanium dioxide powder, which is surface-treated with aluminum hydroxide and stearic acid, has an average particle size distribution of 80nm, and free radicals generated by MT-700Z under ultraviolet irradiation are neutralized with sodium metabisulfite or Emblica, and the actually required concentrations are only 3.2 of the estimated concentrations-1，2.7-1It can be seen that MT-700Z has good compatibility with sodium metabisulfite and Emblica. The invention is proved by tests that when the antioxidant is compounded with inorganic sunscreen, the antioxidant with the strongest oxidation resistance is always the best, the antioxidant which is most suitable for a specific inorganic sunscreen is the best, the proper antioxidant, namely sodium metabisulfite or Emblica, is selected to neutralize free radicals generated by MT-700Z due to illumination, the use efficiency of the oxidant is improved, the use concentration is reduced, and the impact of some strong antioxidants (such as ascorbic acid) on a formula stability system can be avoided or reduced while the optimal protection is provided.
(V) antioxidant matching HPA 30
HPA 30 is a zinc oxide powder, surface-treated with triethoxyoctylsilane, has particle diameter of 30-60nm, and is prepared by neutralizing free radicals generated by HPA 30 under ultraviolet irradiation with EGCG, Emblica and sodium metabisulfite to obtain the concentration of 2.9-1，4.9-1,14.7-1It can be seen that HPA 30 has good compatibility with these 3 antioxidants. The invention proves through tests that when the antioxidant with the strongest oxidation resistance is compounded with the inorganic sunscreen agent, the antioxidant with the strongest oxidation resistance is always the best, the antioxidant which is most suitable for the specific inorganic sunscreen agent is the best, and the proper antioxidant (EGCG or Emblica or sodium metabisulfite) is selected to neutralize free radicals generated by HPA 30 due to ultraviolet irradiationThe use efficiency of the oxidant is improved, the use concentration is reduced, and the impact of some strong antioxidants (such as ascorbic acid) on a formula stability system can be avoided or reduced while the optimal protection is provided.
(VI) antioxidant matching with MZX-508OTS
MZX-508OTS is a kind of zinc oxide powder, surface treated with triethoxy octyl silane, the average particle size distribution is 25nm, EGCG or Emblica or rosmarinic acid is used to neutralize free radical produced by MZX-508OTS under ultraviolet irradiation, the actually required concentration is only 6.2 of the estimated concentration respectively-1，6.9-1,10.1-1It can be seen that MZX-508OTS has good compatibility with these 3 antioxidants. The invention is proved by tests that when the antioxidant is compounded with inorganic sunscreen, the antioxidant with the strongest oxidation resistance is always the best, the antioxidant which is most suitable for the specific inorganic sunscreen is the best, and the proper antioxidant-EGCG or Emblica or rosmarinic acid is selected to neutralize free radicals generated by MZX-508OTS due to ultraviolet irradiation, so that the use efficiency of the oxidant is improved, the use concentration is reduced, and the impact of some strong antioxidants (such as ascorbic acid) on a formula stability system can be avoided or reduced while the optimal protection is provided.
(VII) antioxidant matched with SAMT-Z1
SAMT-Z1 is a zinc oxide powder, which is surface-treated with polydimethylsiloxane and myristic acid to have a particle size of 35nm, and free radicals generated by SAMT-Z1 under ultraviolet irradiation are neutralized with rosmarinic acid, and the concentration actually required is only 12.5 of the estimated concentration-1It can be seen that SAMT-Z1 has good compatibility with rosmarinic acid. The invention is proved by tests that when the antioxidant is compounded with inorganic sunscreen agent, the antioxidant with strongest inoxidizability is always best, the antioxidant which is most suitable for specific inorganic sunscreen agent is best, the proper antioxidant, namely rosmarinic acid is selected to neutralize free radical generated by SAMT-Z1 due to ultraviolet irradiation, the use efficiency of the oxidant is improved, the use concentration is reduced, and the optimal protection is provided, and simultaneously, the phenomenon that some strong antioxidants (such as ascorbic acid) bring to a formula stability system can be avoided or reducedThe impact of (2).
Use examples 1 to 7
Sun-proof emulsion shaking one (W/O type)
Remarking: humuls _ ETE is a compounded emulsifier which comprises dipotassium distearate hectorite, silica dimethyl silylate, cyclopentadimethylsiloxane, polydimethylsiloxane, sunflower (Helianthus Annuus) seed oil, cetyl PEG/PPH-10/1 polydimethylsiloxane, lauryl PEG-9 polydimethylsiloxyethyl polydimethylsiloxane, PEG-10 polydimethylsiloxane, stearic acid, hydrogenated vegetable oil
MZX-508OTS is used for zinc oxide without special indication, MT-10EX is used for titanium dioxide
Preparation process
1. Heating phase A to 85 deg.C, stirring for dissolving, cooling to 60 deg.C
2. And (4) adding the raw materials of the phase B into the phase A in sequence, and stirring and homogenizing uniformly.
3. And (3) dissolving the phase C, uniformly stirring, slowly adding the phase C while stirring A, B mixed phase, slowly adding the phase C, completely adding the phase C, homogenizing for 5 minutes, and finishing the preparation, wherein the appearance of the product is light yellow emulsion.
Use examples 8 to 14
100% physical sunscreen
Remarking: humuls _ ETE is a compounded emulsifier which comprises dipotassium distearate hectorite, silica dimethyl silylate, cyclopentadimethylsiloxane, polydimethylsiloxane, sunflower (Helianthus Annuus) seed oil, cetyl PEG/PPH-10/1 polydimethylsiloxane, lauryl PEG-9 polydimethylsiloxyethyl polydimethylsiloxane, PEG-10 polydimethylsiloxane, stearic acid, hydrogenated vegetable oil
MZX-508OTS is used for zinc oxide without special indication, MT-10EX is used for titanium dioxide
Preparation process
1. Heating phase A to 85 deg.C, stirring for dissolving, cooling to 60 deg.C
2. And (4) adding the raw materials of the phase B into the phase A in sequence, and stirring and homogenizing uniformly.
3. And (3) dissolving the phase C, uniformly stirring, slowly adding the phase C while stirring A, B mixed phase, slowly adding the phase C, completely adding the phase C, homogenizing for 5 minutes, and finishing the preparation, wherein the appearance of the product is white emulsion.
The foregoing is merely a preferred embodiment of the invention and is not intended to limit the scope of the invention, which is defined by the claims appended hereto, and any other technical entity or method that is encompassed by the claims as broadly defined herein, or equivalent variations thereof, is contemplated as being encompassed by the claims.
- 上一篇：一种医用注射器针头装配设备
- 下一篇：一种光彩洁面膏及其制备方法