CN104127335A - Preparation process of easy-clean Pickering emulsion type sunscreen cream containing UV controlled-release medicinal components - Google Patents

Abstract

The invention discloses a preparation process of a Pickering emulsion type sunscreen with UV controlled release of medicinal ingredients and easy to clean. It is prepared by high-speed homogenization, dispersion and emulsification after UV photoresponsive TiO ₂ nanoparticle surfactant, oil phase components and water phase components are blended. First, a TiO ₂ nanoparticle surfactant that stabilizes the Pickering emulsion was prepared by alkyl silane modification, and it was added to the oil phase and mixed with the water phase to emulsify to obtain the target water-in-oil (W/O) emulsion type sunscreen . Nanoparticles have UV photoresponse properties, and after a period of sunlight irradiation, the emulsion can be demulsified and phase-separated and the medicinal ingredients can be released. The method of the invention is simple and convenient, and the obtained product has the characteristics of strong sunscreen effect, light-responsive controlled release of medicinal ingredients, and easy cleaning after a period of sunlight exposure, and has good application prospects in the field of cosmetics industry.

Description

Preparation process of a UV controlled-release medicinal ingredient and easy-to-clean Pickering emulsion type sunscreen

technical field

The invention relates to the field of fine chemicals, especially the field of sunscreen cosmetics. the

Background technique

Sunscreen is known as the "Summer Skin Protector". It can not only effectively isolate ultraviolet rays and prevent the production of melanin and skin cancer, but also has miraculous effects such as sterilization, freckle removal, whitening, and anti-aging. With the development of society and the enhancement of public awareness of sun protection, the characteristics, application and safety of sunscreens have increasingly become the focus of attention. the

In the current daily sunscreens, most of the sunscreens are organic substances such as benzophenone and methoxycinnamate, which have certain toxic side effects and irritation. Inorganic sunscreens containing TiO ₂ nanoparticles have replaced organic sunscreens. become a development trend. At present, sunscreens containing TiO ₂ nanoparticles only use the reflection and scattering effect of TiO ₂ nanoparticles on ultraviolet rays, and organic compounds are inevitably added as surfactants in the preparation process. If you want to get a better sunscreen effect, you must increase the content of _TiO2 nanoparticles or increase the concentration of organic sunscreens. The higher the concentration of organic sunscreen, the heavier the burden on the skin will be, and the increase in TiO ₂ content may affect the stability of the emulsion. The preparation process cannot avoid the toxic side effects and irritation of organic additives (surfactants and organic sunscreens). The inside of the sunscreen paste is in the form of micelles, which is difficult to clean after use and basically does not have the ability to control drug release. Therefore, the sunscreen cosmetics industry urgently needs an inorganic sunscreen that uses only nanoparticles to stabilize the emulsion, which is less irritating to the skin, easy to clean, controllable release of medicinal ingredients, and better sunscreen effect. Inorganic sunscreens that stabilize water-in-oil (W/O) emulsions with UV-responsive _TiO2 particle surfactants can effectively solve the above problems. Compared with the traditional preparation process, TiO ₂ nanoparticles dispersed in the form of wrapped emulsion have good dispersion, are not easy to agglomerate, and have a better sunscreen effect; and the emulsion is photoresponsive. After ultraviolet irradiation, the chemical properties of the particle surface change to cause the emulsion Break the emulsion and release the medicinal ingredients; after the emulsion is broken and phase-separated, the water phase containing the medicinal ingredients contacts the skin and is easy to clean; in addition, the sunscreen formula of the stabilized emulsion with TiO ₂ nanoparticles doped with elements can be used to adapt to different strengths Ultraviolet rays, and control the release of medicinal ingredients, stimulate the ability to clean easily, etc. in different time periods of sunlight exposure. The preparation process will become a new favorite for the preparation of high-efficiency sunscreens due to its advantages of good sunscreen effect, easy cleaning, and controllable release of medicinal ingredients, and it will be a new favorite for the application of Pickering emulsion in biomedicine, cosmetics industry, pharmaceutical engineering and other fields. Provide new ideas.

Contents of the invention

In view of the above deficiencies in the prior art, the present invention aims to provide a preparation process for UV controlled-release medicinal ingredients and an easy-to-clean emulsion type sunscreen, so as to overcome the above deficiencies in the prior art. the

The object of the present invention is achieved by the following means. the

A kind of preparation technology of UV controlled-release medicinal composition and easy-to-clean Pickering emulsion type sunscreen, the steps are as follows:

Step 1: Preparation of TiO ₂ Nanoparticle Surfactant

(a) TiO The preparation of _{nanoparticles} : 1) the volume ratio of each component in the reaction solution is butyl titanate: ethanol: deionized water: glacial acetic acid=9:36:12:40, dehydrated alcohol is added titanic acid In the butyl ester, keep stirring until the mixture is uniform; add the mixture of deionized water and glacial acetic acid dropwise into the mixture of ethanol and butyl titanate under stirring, and keep stirring to obtain a transparent sol; 2) make the transparent sol Transfer to a hydrothermal synthesis reaction kettle for constant temperature reaction at 100-150°C, react for 2-3 hours, remove the clear liquid, and obtain a white TiO ₂ precipitate; 3) Wash the white TiO ₂ precipitate with absolute ethanol, collect the precipitate, and then add anhydrous Fully disperse ethanol and dry to obtain TiO ₂ precipitates; 4) After fully grinding the dried TiO ₂ precipitates, place them in a muffle furnace for calcination at 500°C for 30-60 minutes to obtain photoelectrically active TiO ₂ nanoparticles;

(b) Surface modification of _TiO2 nanoparticles: 1) Take the photoelectrically active _TiO2 nanoparticles obtained in step (a) and disperse them ultrasonically for 5-10 minutes; 2) Seal the dispersion liquid and place it under magnetic stirring in the dark After 4 to 8 hours, remove the seal and dry in an oven at 45 to 60°C; 3) Add the dried powder to trimethylchlorosilane or dodecyl trichlorosilane with a volume ratio of 1 to 5%. In the mixture of silane or fluorosilane and cosmetic grade oil phase, ultrasonically disperse for 5 to 10 minutes, and magnetically stir for 8 to 12 hours, during which the oil phase is continuously replenished to maintain the initial liquid level; 4) The above TiO ₂ dispersion is removed from the clear liquid , dry after precipitation; 5) Fully grind the dried precipitate, evenly disperse it in the cosmetic grade oil phase, and irradiate it with UV light for 24 to 32 hours under magnetic stirring state, during which the oil phase is continuously replenished to maintain the initial solution level; 6 ) After the light is finished, leave the suspension, remove the oil phase after high-speed centrifugation at 15000rpm, precipitate and dry, and after fully grinding, it is _TiO2 nanoparticle surfactant;

Step 2: Preparation of oil phase and water phase ingredients

The TiO2 nanoparticle surfactant prepared in the first step is evenly dispersed in the cosmetic grade oil phase, and the mass percentage concentration of the nanoparticle surfactant and the oil phase is between 1% and 3%; and it is directly mixed with the water phase Mixing, the volume ratio of the oil phase and the water phase is between 3:2 and 7;

Step 3: Prepare the milk of Pickering emulsion sunscreen

Ultrasonic disperse the oil-water mixed solution obtained in the second step for 1 to 5 minutes, and then use a high-speed disperser to homogenize and disperse the dispersion at a speed of 1,5000 rpm for 1 to 5 minutes. After the emulsification is complete, add an appropriate amount of auxiliary materials to obtain the target UV Controlled-release medicinal ingredients and easy-to-rinse Pickering lotion-type sunscreen. the

One or more of the following substances are added to the water phase in the second step: medicinal additives, glycerin and vitamin E with a mass percentage of 0.25% to 0.5%. the

The medicinal additive is one of the following substances: Astragalus membranaceus, apple polyphenols and Panax notoginseng total saponins. the

The invented product obtained by adopting the method of the invention is easy to clean, has good sun protection effect and obvious effect of controlled release of medicinal ingredients, and has the ability of easy cleaning, stronger sun protection effect and extremely obvious effect of controlled release of medicine than traditional organic sunscreens. The stable W/O emulsion begins to demulsify after about 4 hours of UV irradiation, completely breaks and separates phases in about 12 hours, the oil layer floats up, and the medicinal ingredients are released, and the water layer directly contacts the skin, making it easy to clean. Medicinal ingredients with scavenging free radicals, anti-aging effects, etc. have a good protective effect on the skin. The sunscreen prepared by the preparation process has the above advantages mainly due to the transformation of the surface chemical properties of the _TiO2 nanoparticles caused by UV light irradiation. This transition leads to increased instability of the emulsion, which leads to emulsion breaking and phase separation. During the modification process, the grafted chemical groups of TiO ₂ nanoparticles have affinity for the oil phase, and hydroxyl groups are generated on the surface after UV irradiation, which makes the nanoparticles more hydrophilic, and the instability of the emulsion is aggravated, and finally a stable Pickering emulsion is realized. Demulsification and phase separation.

The accompanying drawings are as follows:

Fig. 1 is a schematic diagram of the working principle of the UV controlled-release medicinal composition of the product of the present invention and the easy-to-clean Pickering emulsion type sunscreen:

The TiO ₂ nanoparticle surfactant-stabilized W/O emulsion type sunscreen prepared in this study, after being excited by ultraviolet rays in the sun, the surface chemical properties of the TiO ₂ nanoparticles will change, eventually leading to emulsion breaking and phase separation, which is suitable for medicinal purposes. ingredients are released. The upper layer is mainly an oil phase, and the lower layer is a water phase in which medicinal substances are dissolved, which directly contacts the skin.

Detailed ways

The implementation of the present invention will be further described below in conjunction with the accompanying drawings. However, it should be emphasized that the following embodiments are only exemplary, and are not intended to limit the scope and application of the present invention. The chemical raw materials and reagents involved in the process steps are commercially available commercially pure. the

Example 1

The first step: TiO ₂ nanoparticle surfactant preparation method

(a) Preparation of _TiO2 nanoparticles: Add 36mL of absolute ethanol to 9mL of butyl titanate and keep stirring to get mixed solution A; add 12mL of deionized water to 40mL of glacial acetic acid and keep stirring to get mixed solution b. Add the mixed solution B dropwise to the stirred mixed solution A to prepare a transparent sol (the sol can be doped with N elements to adjust the light response time and intensity). The transparent sol was transferred to a hydrothermal synthesis reactor for a constant temperature reaction at 150 °C for 2 hours, and the supernatant was removed to obtain a white _TiO2 precipitate. Wash the white _TiO2 precipitate with absolute ethanol, centrifuge at 15,000rpm for 10 minutes at high speed, repeat the above operation 3 times, discard the supernatant, collect the precipitate, add absolute ethanol to fully disperse, place it in an oven at 60°C to dry, and obtain The purer _TiO2 precipitates. The dried TiO ₂ precipitates were fully ground and calcined in a muffle furnace at 500°C for 30 minutes to obtain photoelectrically active TiO ₂ nanoparticles.

(b) Surface modification of TiO ₂ nanoparticles: Pour photoelectrically active TiO ₂ nanoparticles into an appropriate amount of H ₂ O ₂ to ensure that the H ₂ O ₂ solution completely immerses the TiO ₂ nanoparticles, and ultrasonically disperse for 5 minutes . Seal the dispersion liquid, place it under magnetic stirring in the dark for 4 hours, remove the seal and dry it in an oven at 45°C. Add the dried powder into a mixture of 1mL dodecyltrichlorosilane and 20mL n-hexane, ultrasonically disperse for 5 minutes, and then magnetically stir for 12 hours to obtain a modified _TiO2 dispersion. Centrifuge the modified TiO ₂ dispersion at 15,000 rpm for 10 minutes at a high speed, remove the supernatant, and dry the lower layer in an oven at 50°C. Fully grind the dried powder and evenly disperse it in n-hexane, and irradiate it with UV light for 24 hours under magnetic stirring (the wavelength of the ultraviolet lamp is 254nm, the power is 12W, and the distance between the solution and the ultraviolet lamp is 10-15cm). liquid level. After the light is finished, let the suspension remain still, centrifuge at 15,000 rpm for 10 minutes at high speed, remove the upper layer of n-hexane, dry the lower layer of precipitate, and fully grind it to become the TiO ₂ nanoparticle surfactant.

Step 2: Preparation and ratio of oil phase and water phase components

Take 0.09g of TiO ₂ nanoparticle surfactant that has photoresponsive properties and make the emulsion break and phase-separate, and add it into 9mL n-hexane dissolved with an appropriate amount of sunscreen ingredients such as olive oil, and then take an appropriate amount of cosmetic grade astragalus, glycerin, vitamin E, etc. Dissolve in 9 mL of deionized water. The two phases of oil and water are mixed directly.

The third step: the emulsification method for preparing Pickering emulsion sunscreen

Ultrasonic disperse the oil-water mixed solution obtained in the second step for 3 minutes, and then use a portable high-speed disperser to homogenize and disperse the dispersion at a high speed of 1,5000 rpm for 3 minutes. After the emulsification is complete, an appropriate amount of essence, preservatives and other auxiliary materials are added to obtain a UV controlled-release medicinal ingredient and easy-to-clean Pickering emulsion type sunscreen. the

Example 2

The first step: TiO ₂ nanoparticle surfactant preparation method

(a) Preparation of _TiO2 nanoparticles: Add 36mL of absolute ethanol to 9mL of butyl titanate and keep stirring to get mixed solution A; add 12mL of deionized water to 40mL of glacial acetic acid and keep stirring to get mixed solution b. Add the mixed solution B dropwise to the stirred mixed solution A to obtain a transparent sol. The transparent sol was transferred to a hydrothermal synthesis reactor for a constant temperature reaction at 150 °C for 2 hours, and the supernatant was removed to obtain a white _TiO2 precipitate. Wash the white _TiO2 precipitate with absolute ethanol, centrifuge at 15,000rpm for 10 minutes at high speed, repeat the above operation 3 times, discard the supernatant, collect the precipitate, add absolute ethanol to fully disperse, place it in an oven at 60°C to dry, and obtain The purer _TiO2 precipitates. The dried TiO ₂ precipitates were fully ground and calcined in a muffle furnace at 500°C for 30 minutes to obtain photoelectrically active TiO ₂ nanoparticles.

(b) Surface modification of TiO ₂ nanoparticles: Pour photoelectrically active TiO ₂ nanoparticles into an appropriate amount of H ₂ O ₂ to ensure that the H ₂ O ₂ solution completely immerses the TiO ₂ nanoparticles, and ultrasonically disperse for 5 minutes . Seal the dispersion liquid, place it under magnetic stirring in the dark for 4 hours, remove the seal and dry it in an oven at 45°C. The dried powder was added to a mixture of 1mL dodecyltrichlorosilane and 20mL kerosene, ultrasonically dispersed for 5 minutes, and then magnetically stirred for 12 hours to obtain a modified _TiO2 dispersion. Centrifuge the modified TiO ₂ dispersion at 15,000 rpm for 10 minutes at a high speed, remove the supernatant, and dry the lower layer in an oven at 50°C. Fully grind the dried powder and evenly disperse it in kerosene, and irradiate it with UV light for 24 hours under magnetic stirring (the wavelength of the UV lamp is 254nm, the power is 12W, and the distance between the solution and the UV lamp is 10-15cm), and the kerosene is continuously replenished during this period to maintain the initial liquid level . After the light is finished, let the suspension remain still, centrifuge at 15,000 rpm for 10 minutes at high speed, remove the upper layer of kerosene, dry the lower layer of sediment, and fully grind it to become the _TiO2 nanoparticle surfactant.

Step 2: Preparation and ratio of oil phase and water phase components

Take 0.09 g of TiO ₂ nanoparticle surfactant which has photoresponse characteristics and make the emulsion break and phase-separate, and add it into 9 mL of kerosene dissolved with an appropriate amount of olive oil and other sunscreen ingredients, and then take an appropriate amount of cosmetic grade astragalus, glycerin, vitamin E, etc. in 9 mL of deionized water. The two phases of oil and water are mixed directly.

The third step: the emulsification method for preparing Pickering emulsion sunscreen

Ultrasonic disperse the oil-water mixed solution obtained in the second step for 3 minutes, and then use a portable high-speed disperser to homogenize and disperse the dispersion at a high speed of 1,5000 rpm for 3 minutes. After the emulsification is complete, an appropriate amount of essence, preservatives and other auxiliary materials are added to obtain a UV controlled-release medicinal ingredient and easy-to-clean Pickering emulsion type sunscreen. the

Example 3

The oil phase is replaced with No. 26 white oil of cosmetic grade, and other steps are as described in Example 1 and Example 2. the

After diluting the self-made Pickering emulsion sunscreen and the traditional organic sunscreen to the same multiple, the absorbance was measured respectively. According to the drawn ultraviolet wavelength scanning chart, the self-made Pickering emulsion sunscreen has better sun protection effect than the traditional organic sunscreen. This is because the TiO ₂ nanoparticles in the self-made Pickering emulsion type sunscreen not only reflect and scatter ultraviolet rays, but also have a strong absorption effect on ultraviolet rays. At the same time, the self-made Pickering emulsion sunscreen and the traditional organic sunscreen were applied to the same carrier in equal doses, and the residues were cleaned after equal time and intensity of light, and the cleaning effect of the self-made Pickering emulsion sunscreen was obvious. The main reason is that the content of organic sunscreens, emulsifiers and other organic substances in traditional organic sunscreens is high, while self-made Pickering emulsion sunscreens use TiO ₂ nanoparticle surfactants with sunscreen effects to stabilize the emulsion. After being irradiated by sunlight, TiO ₂ The chemical properties of the surface of the nanoparticles change, which leads to the demulsification and phase separation of the emulsion, the oil phase floats up, and the water phase contacts the skin, which is easy to clean. During the modification process, the grafted chemical groups of TiO ₂ nanoparticles have affinity for the oil phase, and hydroxyl groups are generated on the surface after UV irradiation, which makes the nanoparticles more hydrophilic, and the instability of the emulsion is aggravated, and finally a stable Pickering emulsion is realized. Demulsification and phase separation. Finally, after observing the demulsification and phase separation effect of the self-made Pickering emulsion sunscreen after irradiation, and studying the release of medicinal ingredients with the irradiation time, it was found that the self-made Pickering emulsion sunscreen was completely phase-separated after about 12 hours of irradiation, and the release of medicinal ingredients could be as follows: Up to 90% or more.

The self-made Pickering emulsion sunscreen obtained by the present invention will become the new darling of the preparation of high-efficiency sunscreen by virtue of its good sunscreen effect, easy cleaning, and controllable release of medicinal ingredients, and it will become a new favorite for the Pickering emulsion in the biomedical, cosmetics industries, Applications in pharmaceutical engineering and other fields provide new ideas. the

Claims (4)

1. A kind of preparation technology of UV controlled-release medicinal composition and easy-to-clean Pickering emulsion type sunscreen, the steps are as follows: Step 1: Preparation of TiO ₂ Nanoparticle Surfactant (a) TiO The preparation of _{nanoparticles} : 1) the volume ratio of each component in the reaction solution is butyl titanate: ethanol: deionized water: glacial acetic acid=9:36:12:40, dehydrated alcohol is added titanic acid In the butyl ester, keep stirring until the mixture is uniform; add the mixture of deionized water and glacial acetic acid dropwise into the mixture of ethanol and butyl titanate under stirring, and keep stirring to obtain a transparent sol; 2) make the transparent sol Transfer to a hydrothermal synthesis reaction kettle for constant temperature reaction at 100-150°C, react for 2-3 hours, remove the clear liquid, and obtain a white TiO ₂ precipitate; 3) Wash the white TiO ₂ precipitate with absolute ethanol, collect the precipitate, and then add anhydrous Fully disperse ethanol and dry to obtain TiO ₂ precipitates; 4) After fully grinding the dried TiO ₂ precipitates, place them in a muffle furnace for calcination at 500°C for 30-60 minutes to obtain photoelectrically active TiO ₂ nanoparticles; (b) Surface modification of _TiO2 nanoparticles: 1) Take the photoelectrically active _TiO2 nanoparticles obtained in step (a) and disperse them ultrasonically for 5-10 minutes; 2) Seal the dispersion liquid and place it under magnetic stirring in the dark After 4 to 8 hours, remove the seal and dry in an oven at 45 to 60°C; 3) Add the dried powder to trimethylchlorosilane or dodecyltrichlorohydrin with a volume ratio of 1 to 5%. In the mixture of silane or fluorosilane and cosmetic grade oil phase, ultrasonically disperse for 5 to 10 minutes, and magnetically stir for 8 to 12 hours, during which the oil phase is continuously replenished to maintain the initial liquid level; 4) The above TiO ₂ dispersion is removed from the clear liquid , dry after precipitation; 5) Fully grind the dried precipitate, evenly disperse it in the cosmetic grade oil phase, and irradiate it with UV light for 24 to 32 hours under magnetic stirring state, during which the oil phase is continuously replenished to maintain the initial solution level; 6 ) After the light is finished, leave the suspension, remove the oil phase after high-speed centrifugation at 15000rpm, precipitate and dry, and after fully grinding, it is _TiO2 nanoparticle surfactant; Step 2: Preparation of oil phase and water phase ingredients The _{TiO2nanoparticle} surfactant prepared in the first step is evenly dispersed in the cosmetic grade oil phase, the mass percent concentration of the nanoparticle surfactant and the oil phase is between 1% and 3%; and it is mixed with the water phase Mix directly, the volume ratio of oil phase and water phase is between 3:2~7; Step 3: Prepare the milk of Pickering emulsion sunscreen Ultrasonic disperse the oil-water mixed solution obtained in the second step for 1 to 5 minutes, and then use a high-speed disperser to homogenize and disperse the dispersion at a speed of 1,5000 rpm for 1 to 5 minutes. After the emulsification is complete, add an appropriate amount of auxiliary materials to obtain the target UV Controlled-release medicinal ingredients and easy-to-rinse Pickering lotion-type sunscreen. 2. the preparation technology of UV controlled-release medicinal composition according to claim 1 and easy-to-clean Pickering emulsion type sunscreen, it is characterized in that, in the oil phase in the second step, an appropriate amount of olive oil is added. 3. The preparation process of UV controlled release medicinal composition according to claim 1 and easy to clean Pickering emulsion type sunscreen, it is characterized in that, in the water phase in the second step, one or more of the following substances are added : The mass percentage is 0.25%～0.5% medicinal additives, glycerin, vitamin E. 4. The preparation process of the UV controlled-release medicinal composition according to claim 2 and the easy-to-clean Pickering emulsion sunscreen, wherein the medicinal additive is one of the following substances: astragalus, apple polyphenols, Panax notoginseng saponins.