Functionalized meso-porous silicon particle, Pickering emulsion and preparation method and application of functionalized meso-porous silicon particle and Pickering emulsion

Abstract

The invention relates to the technical field of Pickering emulsion preparation, and discloses a functionalized mesoporous silicon particle, a Pickering emulsion as well as a preparation method and application of the Pickering emulsion. The functionalized meso-porous silicon particles comprise meso-porous silicon particles and silicon dioxide shell layers coating the surfaces of the meso-porous silicon particles; wherein an ultraviolet filtering agent is loaded in the meso-porous silicon particles. The functionalized meso-porous silicon particle provided by the invention not only reduces free radicals generated by photodegradation of an ultraviolet filtering agent by 89.3%, effectively overcomes the contradiction of'protection-damage 'in traditional ultraviolet protection, but also reduces the wettability of the particle from 114.7 degrees to 89.6 degrees, so that the particle has excellent emulsion stability and ultraviolet shielding function, and meanwhile, the functional meso-porous silicon particle can be applied to the field of ultraviolet protection. The secondary silicon layer packaging also reduces the leakage of the ultraviolet filtering agent; when the functionalized meso-porous silicon particle is used as an emulsifier for preparing a Pickering emulsion carrying a photosensitive active matter, a corresponding ultraviolet filtering agent is matched aiming at a sensitive wave band (UVA or UVB) of the photosensitive active matter, so that customized and high-efficiency light protection is realized.

Description

Technical Field

[0001] This invention relates to the field of Pickering emulsion preparation technology, and particularly to a functionalized mesoporous silica particle, a Pickering emulsion, its preparation method and application. Background Technology

[0002] Photosensitive bioactive substances, such as astaxanthin, resveratrol, and vitamin E, have broad application prospects in pharmaceuticals, functional foods, and cosmetics due to their significant antioxidant, anti-inflammatory, and anti-aging physiological functions. However, these active molecules typically contain a large number of unsaturated bonds, making them highly susceptible to photo-oxidation, isomerization, or degradation under environmental stresses such as light (especially ultraviolet radiation), oxygen, or high temperatures. This leads to a rapid loss of their biological activity, severely limiting their practical application and product stability.

[0003] To enhance the environmental stability of active ingredients, Pickering emulsions, as emulsion systems stabilized by solid particles, are considered ideal carriers for encapsulating and protecting sensitive active ingredients due to their unique interfacial barrier effect and physical isolation capabilities. Functional modification of emulsion particles can further endow emulsions with antioxidant and UV-resistant properties. For example, studies have shown that antioxidants are grafted onto the surface of emulsion particles to achieve oxidative protection against oxidation of active ingredients in the emulsion phase; other researchers have used natural polyphenols with UV absorption capabilities to modify milk proteins, preparing Pickering emulsions with a certain degree of light-shielding function. However, because ultraviolet light (especially UVA, 320-400nm) has strong penetrating power, traditional emulsion interfaces cannot completely block its entry into the oil droplets, causing the encapsulated active ingredients to rapidly deactivate under long-term light exposure. In existing technologies, the ultraviolet absorption bands of natural biomass particles (such as lignin and polyphenol-protein complexes) are mostly concentrated in the UVB region, and their protection effect against UVA is limited. On the other hand, although inorganic ultraviolet shielding particles (such as TiO2) have a broad absorption spectrum, they are prone to generating free radicals under ultraviolet irradiation, which in turn aggravates the degradation of active substances and forms a vicious cycle of "protection-destruction".

[0004] In recent years, although some studies have attempted to improve the UV shielding ability of particles through composite modification, such as grafting poly(N-isopropylacrylamide) onto lignin to prepare light-stable particles, or co-modifying milk proteins with polyphenols and glycosylation, these systems still suffer from problems such as short protection time, incomplete wavelength coverage, and significant free radical side effects. For example, a study reported that a resveratrol Pickering emulsion had a retention rate of only 50% after 3 hours of UV irradiation, while another system using TiO2 nanoparticles had a retention rate of approximately 80% under the same conditions. However, these systems still fall short of the stability requirements for long-term storage and use in actual production.

[0005] Therefore, inventing a Pickering emulsion system that combines efficient UV shielding, free radical suppression, and tunable UV protection is crucial for achieving long-term stability of photosensitive active ingredients. Summary of the Invention

[0006] The present invention aims to at least solve one of the aforementioned technical problems existing in the prior art. Therefore, one object of the present invention is to provide a functionalized mesoporous silicon particle.

[0007] The second objective of this invention is to provide a method for preparing such functionalized mesoporous silicon particles.

[0008] The third objective of this invention is to provide applications for such functionalized mesoporous silicon particles.

[0009] The fourth objective of this invention is to provide a Pickering emulsion.

[0010] The fifth objective of this invention is to provide a method for preparing such a Pickering emulsion.

[0011] The sixth object of the present invention is to provide an application of this Pickering emulsion.

[0012] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A first aspect of the present invention provides a functionalized mesoporous silicon particle, comprising mesoporous silicon particles and a silica shell coating the surface of the mesoporous silicon particles; wherein the mesoporous silicon particles are loaded with an ultraviolet filter.

[0013] In some embodiments of the present invention, the functionalized mesoporous silicon particles comprise the following raw materials: silicon source, alkaline catalyst, ultraviolet filter and cationic surfactant.

[0014] In some embodiments of the present invention, the silicon source is selected from at least one of tetraethyl orthosilicate, methyl orthosilicate, and isopropyl orthosilicate.

[0015] In some preferred embodiments of the present invention, the silicon source is tetraethyl orthosilicate.

[0016] In some embodiments of the present invention, the ultraviolet filter is selected from UVA band filters or UVB band filters.

[0017] In some preferred embodiments of the present invention, the UVA band filter refers to an organic compound capable of selectively absorbing or shielding ultraviolet rays with wavelengths in the range of 320-400nm, and may be selected from at least one of butyl methoxydibenzoylmethane (avobenzone), methyl anthranilate (melardizoline), and ethyl diethylaminohydroxybenzoylbenzoate.

[0018] In some preferred embodiments of the present invention, the UVB band filter refers to an organic compound capable of selectively absorbing or shielding ultraviolet rays with wavelengths in the range of 290-320 nm, and may be selected from at least one of ethylhexyl methoxycinnamate, p-methoxycinnamate esters, camphor derivatives, and benzotriazole ultraviolet absorbers.

[0019] In some embodiments of the present invention, the alkaline catalyst is selected from ammonia or organic amines.

[0020] In some preferred embodiments of the present invention, the alkaline catalyst is selected from at least one of ammonia, ethylenediamine, and triethylamine.

[0021] In some more preferred embodiments of the present invention, the alkaline catalyst is ammonia water with a concentration of 20wt%-30wt%.

[0022] In some embodiments of the present invention, the cationic surfactant is selected from at least one of hexadecyltrimethylammonium bromide, hexadecyltrimethylammonium chloride, and tetradecyltrimethylammonium bromide.

[0023] In some preferred embodiments of the present invention, the cationic surfactant is hexadecyltrimethylammonium bromide (CTAB).

[0024] A second aspect of the present invention provides a method for preparing the functionalized mesoporous silicon particles described in the first aspect of the present invention, comprising the following steps: S1. Disperse the ultraviolet filter in a first solvent to form dispersion I, disperse the cationic surfactant in a second solvent to form dispersion II, and mix dispersion I and dispersion II to obtain a mixture; S2. Add silicon source and alkaline catalyst dropwise to the mixture in sequence, react, and obtain mesoporous silicon particles carrying ultraviolet filter. S3. Disperse the ultraviolet-loaded mesoporous silica particles in water to form dispersion III, and add silicon source and alkaline catalyst in sequence to react and obtain the functionalized mesoporous silica particles. Wherein, the first solvent is selected from C1-C4 alkanols; the second solvent is selected from aqueous solutions of C1-C4 alkanols.

[0025] It should be noted that the silicon source and alkaline catalyst used in steps S2 and S3 may be the same or different. Specifically, the silicon source used in steps S2 and S3 is independently selected from at least one of tetraethyl orthosilicate, methyl orthosilicate, and isopropyl orthosilicate; and the alkaline catalyst is independently selected from ammonia or organic amine.

[0026] In some embodiments of the present invention, in step S1, the concentration of the ultraviolet filter in dispersion I is 6-10 mg / L; the concentration of the cationic surfactant in dispersion II is 4-6 mg / L; and the volume ratio of dispersion I to dispersion II in the mixture is (3-5):1.

[0027] In some preferred embodiments of the present invention, in step S1, the concentration of the ultraviolet filter in dispersion I is 7-9 mg / L; the concentration of the cationic surfactant in dispersion II is 4.5-5.5 mg / L; and the volume ratio of dispersion I to dispersion II in the mixture is (3.5-4.5):1.

[0028] In some embodiments of the present invention, in step S1, the mixing process of dispersion I and dispersion II is supplemented by stirring at a speed of 400-600 rpm for a time of 0.8-1.2 h.

[0029] In some preferred embodiments of the present invention, in step S1, the mixing process of dispersion I and dispersion II is supplemented by stirring at a speed of 450-550 rpm for a time of 0.9-1.1 h.

[0030] In some embodiments of the present invention, in step S2, the volume ratio of the silicon source to the alkaline catalyst is (4-6): 1: (52-78).

[0031] In some preferred embodiments of the present invention, in step S2, the volume ratio of the silicon source to the alkaline catalyst is (4.5-5.5): 1: (58-72).

[0032] In some embodiments of the present invention, in step S2, the process of adding the silicon source and the alkaline catalyst is accompanied by stirring, and the stirring speed is 400-600 rpm.

[0033] In some preferred embodiments of the present invention, in step S2, the process of adding silicon source and alkaline catalyst is accompanied by stirring, and the stirring speed is 450-550 rpm.

[0034] In some embodiments of the present invention, in step S2, the reaction process is aided by stirring at a speed of 650-950 rpm for 2-4 hours.

[0035] In some preferred embodiments of the present invention, in step S2, the reaction process is aided by stirring at a speed of 750-850 rpm for 2-3 hours.

[0036] In some embodiments of the present invention, after the reaction is completed in step S2, the solid phase is further separated and collected, washed, and dried to obtain mesoporous silica particles carrying ultraviolet filter.

[0037] In some embodiments of the present invention, in step S3, the concentration of dispersion III is 1.4-2.2 mg / L; the volume ratio of the silicon source and the alkaline catalyst is (1-2):1.

[0038] In some preferred embodiments of the present invention, in step S3, the concentration of dispersion III is 1.6-2.0 mg / L; and the volume ratio of the silicon source and the alkaline catalyst is (1-1.5):1.

[0039] In some embodiments of the present invention, in step S3, the process of adding the silicon source and the alkaline catalyst is accompanied by stirring at a speed of 400-600 rpm.

[0040] In some preferred embodiments of the present invention, in step S3, the process of adding the silicon source and the alkaline catalyst is accompanied by stirring at a speed of 450-550 rpm.

[0041] In some embodiments of the present invention, in step S3, the reaction process is aided by stirring at a speed of 450-750 rpm for 2-4 hours.

[0042] In some preferred embodiments of the present invention, in step S3, the reaction process is aided by stirring at a speed of 550-650 rpm for 2-3 hours.

[0043] In some embodiments of the present invention, step S3, after the reaction is completed, further includes solid-liquid separation to collect the solid phase, washing, and drying to obtain functionalized mesoporous silicon particles.

[0044] In some embodiments of the present invention, in step S3, the solid-liquid separation method includes centrifugation.

[0045] In some embodiments of the present invention, in step S3, the washing includes washing with water and ethanol 2-4 times each.

[0046] In some embodiments of the present invention, in step S3, the drying temperature is 40-45°C and the time is 20-25 hours.

[0047] In some embodiments of the present invention, the volume ratio of C1-C4 alkanol to water in the second solvent is (1-4):1.

[0048] In some preferred embodiments of the present invention, the volume ratio of C1-C4 alkanol to water in the second solvent is (1.5-2):1.

[0049] In some preferred embodiments of the present invention, the first solvent is ethanol; the second solvent is an aqueous solution of ethanol.

[0050] A third aspect of the present invention provides the use of the functionalized mesoporous silica particles described in the first aspect of the present invention as an emulsifier in the preparation of Pickering emulsions.

[0051] A fourth aspect of the present invention provides a Pickering emulsion comprising an aqueous phase and an oil phase; The oil phase includes photosensitizing active ingredients and C8-C12 fatty acid triglycerides; The aqueous phase comprises the functionalized mesoporous silicon particles described in the first aspect of the present invention and water.

[0052] In some embodiments of the present invention, the volume ratio of the aqueous phase to the oil phase is (1-1.5):1.

[0053] In some preferred embodiments of the present invention, the volume ratio of the aqueous phase to the oil phase is (1-1.3):1.

[0054] In some embodiments of the present invention, the concentration of the photosensitive active ingredient in the oil phase is 0.06-10 mg / mL.

[0055] In some embodiments of the present invention, the photosensitive active material is selected from photosensitive active materials that are easily deactivated in the UVA band or photosensitive active materials that are easily deactivated in the UVB band.

[0056] In some preferred embodiments of the present invention, the UVA band photosensitive active ingredient that is easily deactivated includes at least one of astaxanthin and β-carotene.

[0057] In some preferred embodiments of the present invention, the UVB band photosensitive active ingredient that is easily deactivated includes at least one of resveratrol and vitamin E.

[0058] In some embodiments of the present invention, the C8-C12 fatty acid triglyceride is selected from at least one of caprylic / capric triglyceride and capric triglyceride.

[0059] In some preferred embodiments of the present invention, the C8-C12 fatty acid triglyceride is caprylic / capric triglyceride (GTCC).

[0060] In some embodiments of the present invention, the concentration of the functionalized mesoporous silicon particles in the aqueous phase is 1.0wt%-2.5wt%.

[0061] In some preferred embodiments of the present invention, the concentration of the functionalized mesoporous silicon particles in the aqueous phase is 1.5wt%-2.0wt%.

[0062] The fifth aspect of the present invention provides a method for preparing the Pickering emulsion described in the fourth aspect of the present invention, comprising the following steps: The aqueous phase and the oil phase are mixed to obtain the Pickering emulsion.

[0063] In some embodiments of the present invention, the method for preparing the Pickering emulsion specifically includes the following steps: The photosensitizing active ingredient is ultrasonically dispersed in C8-C12 fatty acid triglycerides to form an oil phase; functionalized mesoporous silica particles are dispersed in water to form an aqueous phase; the aqueous phase and the oil phase are mixed to obtain the Pickering emulsion.

[0064] In some embodiments of the present invention, the ultrasonic dispersion time is 2-5 min, and the mixing time of the aqueous phase and the oil phase is 1-2 min.

[0065] The sixth aspect of the present invention provides the use of the Pickering emulsion described in the fourth aspect of the present invention in the preparation of photostable cosmetics, pharmaceutical preparations or functional foods.

[0066] Compared with the prior art, the beneficial effects of the present invention are: The functionalized mesoporous silica particles provided by this invention load ultraviolet (UV) filters onto the mesoporous silica particles and then encapsulate the UV filter-loaded mesoporous silica particles with a secondary silicon layer. This not only reduces the free radicals generated by the photodegradation of the UV filter by 89.3%, effectively overcoming the "protection-destruction" contradiction in traditional UV protection, but also reduces the wettability of the particles from 114.7° to 89.6°, giving them both excellent emulsification stability and UV shielding function. Simultaneously, the secondary silicon layer encapsulation also reduces UV filter leakage. When these functionalized mesoporous silica particles are used as emulsifiers in the preparation of Pickering emulsions carrying photosensitive active ingredients, customized and highly efficient photoprotection is achieved by matching the appropriate UV filter to the sensitive wavelength band (UVA or UVB) of the photoactive ingredient. The Pickering emulsion preparation process is simple and the raw materials are safe, providing a solution for the long-term stability of various photosensitive active ingredients in cosmetics, pharmaceuticals, and other fields. Attached Figure Description

[0067] Figure 1 TEM images of mesoporous silicon particles (a) in Comparative Example 5, mesoporous silicon particles (b) loaded with avobenzone in Example 1, and functionalized mesoporous silicon particles (c). Figure 2 FTIR images of mesoporous silicon particles (a) in Comparative Example 5, avobenzone and functionalized mesoporous silicon particles in Example 1; Figure 3The UV absorption spectra are for avobenzone, avobenzone-loaded mesoporous silicon particles, functionalized mesoporous silicon particles in Example 1, and mesoporous silicon particles in Comparative Example 5. Figure 4 The results of photocatalytic activity tests on avobenzone and functionalized mesoporous silica particles in Example 2 are shown. Figure 5 The results of the three-phase contact angle test of the functionalized mesoporous silicon particles in Example 2; Figure 6 The emulsion morphology formed by the functionalized mesoporous silica particles in Example 2; Figure 7 The absorption spectra of astaxanthin and vitamin E in the UVA and UVB bands; Figure 8 This is a graph showing the degradation rate of astaxanthin in the UVA and UVB bands. Figure 9 This is a graph showing the degradation rate of vitamin E under UVA and UVB bands. Figure 10 The light absorption characteristics of the emulsion systems stabilized by functionalized mesoporous silica particles in Examples 1 and 3; Figure 11 The photostability of astaxanthin in the emulsion systems stabilized by functionalized mesoporous silica particles in Examples 1 and 3; Figure 12 The photostability of vitamin E in the emulsion systems stabilized by functionalized mesoporous silica particles in Examples 1 and 3; Figure 13 The graph shows the color change of the Pickering emulsion in Example 1 and the oil phase in Comparative Example 1. Figure 14 The graph shows the color changes of the Pickering emulsion in Example 2 and the oil phase in Comparative Example 2. Figure 15 The graph shows the color change of the Pickering emulsion in Example 3 and the oil phase in Comparative Example 3. Figure 16 The graph shows the color change of the Pickering emulsion in Example 4 and the oil phase in Comparative Example 4. Figure 17 The astaxanthin retention rate in the Pickering emulsion loaded with astaxanthin in Example 1 after 10 days of UV irradiation; Figure 18 The free radical scavenging activity of astaxanthin in Pickering emulsion loaded with astaxanthin in Example 1 after 10 days of UV irradiation. Detailed Implementation

[0068] The present invention will be further described in detail below through specific embodiments. Unless otherwise specified, the raw materials, reagents, or apparatus used in the embodiments and comparative examples are all available from conventional commercial sources or can be obtained by existing technical methods. Unless otherwise specified, the test or experimental methods are conventional methods in the art.

[0069] Example 1 In this embodiment, a functionalized mesoporous silica particle is prepared, and a Pickering emulsion is prepared using the functionalized mesoporous silica particle as an emulsifier. The preparation steps of functionalized mesoporous silicon particles are as follows: S11. Disperse avobenzone in ethanol to form dispersion I with a concentration of 8 mg / mL; disperse hexadecyltrimethylammonium bromide in an aqueous ethanol solution (ethanol:water = 2:1, v / v) to form dispersion II with a concentration of 5 mg / mL. S12. Mix dispersion I and dispersion II at a volume ratio of 1:4, and stir at 500 rpm for 1 hour to obtain a mixture. S21. Tetraethyl orthosilicate and 25wt% ammonia water (tetraethyl orthosilicate: ammonia water: mixture = 5: 1: 65, v / v / v) were added dropwise to the mixture at 500 rpm. After the addition was completed, the mixture was stirred at 800 rpm for 3 h, washed and dried to obtain mesoporous silica particles loaded with avobenzone. S31. Avobenzone-loaded mesoporous silica particles were dispersed in water to form a dispersion III with a concentration of 1.82 mg / mL. Tetraethyl orthosilicate and ammonia (25 wt%) were added dropwise to the mixture at a volume ratio of 5:4 at 500 rpm. After the addition was completed, the mixture was stirred at 600 rpm for 3 h. The solid product was collected by centrifugation, washed three times each with deionized water and ethanol, and dried in an oven at 42 ℃ for 24 h to obtain functionalized mesoporous silica particles.

[0070] The preparation steps for the pickingering emulsion are as follows: 1) Astaxanthin was ultrasonically dispersed in caprylic / capric triglyceride for 3 min to obtain an oil phase with an astaxanthin concentration of 0.06 mg / mL; functionalized mesoporous silica particles were dispersed in water to obtain an aqueous phase with a functionalized mesoporous silica particle concentration of 1.5 wt%. 2) Mix the aqueous phase and oil phase at a volume ratio of 6:5 and shake by hand for 1 minute to obtain the Pickering emulsion loaded with astaxanthin.

[0071] Example 2 In this embodiment, a functionalized mesoporous silica particle is prepared, and a Pickering emulsion is prepared using the functionalized mesoporous silica particle as an emulsifier. The preparation steps of functionalized mesoporous silicon particles are as follows: S11. Disperse avobenzone in ethanol to form dispersion I with a concentration of 8 mg / mL; disperse hexadecyltrimethylammonium bromide in an aqueous ethanol solution (ethanol:water = 2:1, v / v) to form dispersion II with a concentration of 5 mg / mL. S12. Mix dispersion I and dispersion II at a volume ratio of 1:4, and stir at 500 rpm for 1 hour to obtain a mixture. S21. At a speed of 500 rpm, tetraethyl orthosilicate and 25 wt% ammonia water were added dropwise to the mixture (tetraethyl orthosilicate: ammonia water: mixture = 5: 1: 65, v / v / v). After the addition was completed, the mixture was stirred at 800 rpm for 3 h, washed and dried to obtain mesoporous silica particles loaded with avobenzone. S31. Avobenzone-loaded mesoporous silica particles were dispersed in water to form a dispersion III with a concentration of 1.82 mg / mL. Tetraethyl orthosilicate and ammonia (25 wt%) were added dropwise to the mixture at a volume ratio of 5:4 at 500 rpm. After the addition was completed, the mixture was stirred at 600 rpm for 3 h. The solid product was collected by centrifugation, washed three times each with deionized water and ethanol, and dried in an oven at 42 ℃ for 24 h to obtain functionalized mesoporous silica particles.

[0072] The preparation steps for the pickingering emulsion are as follows: 1) β-carotene was ultrasonically dispersed in caprylic / capric triglyceride for 3 min to obtain an oil phase with a β-carotene concentration of 0.6 mg / mL; functionalized mesoporous silica particles were dispersed in water to obtain an aqueous phase with a functionalized mesoporous silica particle concentration of 2 wt%. 2) Mix the aqueous phase and oil phase at a volume ratio of 6:5 and shake by hand for 1 minute to obtain a Pickering emulsion loaded with β-carotene.

[0073] Example 3 In this embodiment, a functionalized mesoporous silica particle is prepared, and a Pickering emulsion is prepared using the functionalized mesoporous silica particle as an emulsifier. The preparation steps of functionalized mesoporous silicon particles are as follows: S11. Ethylhexyl methoxycinnamate is dispersed in ethanol to form dispersion I with a concentration of 8 mg / mL; hexadecyltrimethylammonium bromide is dispersed in an aqueous ethanol solution (ethanol: water = 2: 1, v / v) to form dispersion II with a concentration of 5 mg / mL. S12. Mix dispersion I and dispersion II at a volume ratio of 1:4, and stir at 500 rpm for 1 hour to obtain a mixture. S21. At a speed of 500 rpm, tetraethyl orthosilicate and 25 wt% ammonia water were added dropwise to the mixture (tetraethyl orthosilicate: ammonia water: mixture = 5: 1: 65, v / v / v). After the addition was completed, the mixture was stirred at 800 rpm for 3 h, washed and dried to obtain mesoporous silica particles loaded with ethylhexyl methoxycinnamate. S31. Mesoporous silica particles loaded with ethylhexyl methoxycinnamate were dispersed in water to form a dispersion III with a concentration of 1.82 mg / mL. Ethyl orthosilicate and ammonia (25 wt%) were added dropwise to the mixture at a volume ratio of 5:4 at 500 rpm. After the addition was completed, the mixture was stirred at 600 rpm for 3 h. The solid product was collected by centrifugation, washed three times each with deionized water and ethanol, and dried in an oven at 42 ℃ for 24 h to obtain functionalized mesoporous silica particles.

[0074] The preparation steps for the pickingering emulsion are as follows: 1) Vitamin E was ultrasonically dispersed in caprylic / capric triglyceride for 3 min to obtain an oil phase with a vitamin E concentration of 1 mg / mL; functionalized mesoporous silica particles were dispersed in water to obtain an aqueous phase with a functionalized mesoporous silica particle concentration of 1.5 wt%. 2) Mix the aqueous phase and oil phase at a volume ratio of 6:5 and shake by hand for 1 minute to obtain a vitamin E-loaded Pickering emulsion.

[0075] Example 4 In this embodiment, a functionalized mesoporous silica particle is prepared, and a Pickering emulsion is prepared using the functionalized mesoporous silica particle as an emulsifier. The preparation steps of functionalized mesoporous silicon particles are as follows: S11. Ethylhexyl methoxycinnamate is dispersed in ethanol to form dispersion I with a concentration of 8 mg / mL; hexadecyltrimethylammonium bromide is dispersed in an aqueous ethanol solution (ethanol: water = 2: 1, v / v) to form dispersion II with a concentration of 5 mg / mL. S12. Mix dispersion I and dispersion II at a volume ratio of 1:4, and stir at 500 rpm for 1 hour to obtain a mixture. S21. At a speed of 500 rpm, tetraethyl orthosilicate and 25 wt% ammonia water were added dropwise to the mixture (tetraethyl orthosilicate: ammonia water: mixture = 5: 1: 65, v / v / v). After the addition was completed, the mixture was stirred at 800 rpm for 3 h, washed and dried to obtain mesoporous silica particles loaded with ethylhexyl methoxycinnamate. S31. Mesoporous silica particles loaded with ethylhexyl methoxycinnamate were dispersed in water to form a dispersion III with a concentration of 1.82 mg / mL. Ethyl orthosilicate and ammonia (25 wt%) were added dropwise to the mixture at a volume ratio of 5:4 at 500 rpm. After the addition was completed, the mixture was stirred at 600 rpm for 3 h. The solid product was collected by centrifugation, washed three times each with deionized water and ethanol, and dried in an oven at 42 ℃ for 24 h to obtain functionalized mesoporous silica particles.

[0076] The preparation steps for the pickingering emulsion are as follows: 1) Resveratrol was ultrasonically dispersed in caprylic / capric triglyceride for 3 min to obtain an oil phase with a resveratrol concentration of 10 mg / mL; functionalized mesoporous silica particles were dispersed in water to obtain an aqueous phase with a functionalized mesoporous silica particle concentration of 2 wt%. 2) Mix the aqueous phase and oil phase at a volume ratio of 6:5 and shake by hand for 1 minute to obtain a Pickering emulsion loaded with resveratrol.

[0077] Comparative Example 1 Astaxanthin was ultrasonically dispersed in caprylic / capric triglyceride for 3 minutes to obtain an oil phase with an astaxanthin concentration of 0.06 mg / mL.

[0078] Comparative Example 2 β-carotene was ultrasonically dispersed in caprylic / capric triglyceride for 3 minutes to obtain an oil phase with a β-carotene concentration of 0.6 mg / mL.

[0079] Comparative Example 3 Vitamin E was ultrasonically dispersed in caprylic / capric triglyceride for 3 minutes to obtain an oil phase with a vitamin E concentration of 1 mg / mL.

[0080] Comparative Example 4 Resveratrol was ultrasonically dispersed in caprylic / capric triglyceride for 3 minutes to obtain an oil phase with a resveratrol concentration of 10 mg / mL.

[0081] Comparative Example 5 Hexadecyltrimethylammonium bromide was dispersed in an aqueous ethanol solution (ethanol:water = 2:1, v / v) to form dispersion II with a concentration of 5 mg / mL. Tetraethyl orthosilicate and 25 wt% ammonia water (tetraethyl orthosilicate:ammonia water:dispersion II = 5:1:65, v / v / v) were added dropwise to dispersion II at a volume ratio of 5:1. After the addition was completed, the mixture was stirred at 800 rpm for 3 h, eluted and dried to obtain mesoporous silica particles.

[0082] Material characterization and performance testing: 1. The morphology of the avobenzone-loaded mesoporous silica particles, functionalized mesoporous silica particles, and mesoporous silica particles in Comparative Example 5 was tested. Specifically, the particles were dispersed in anhydrous ethanol and sonicated at 100W for 2 min to obtain sample solutions. The morphological characteristics of the particles were then observed under a transmission electron microscope. Figure 1 The TEM images are of the mesoporous silicon particles (a) in Comparative Example 5, the avobenzone-loaded mesoporous silicon particles (b) and the functionalized mesoporous silicon particles (c) in Example 1. Figure 1 It can be seen that, compared with mesoporous silica particles, the characteristic light and dark contrast of the surface of avobenzone-loaded mesoporous silica particles is significantly reduced, indicating that the UV filter avobenzone molecules have been successfully filled into the mesoporous channels of the particles; the silicon shell layer on the surface of the functionalized mesoporous silica particles can be clearly observed in the TEM image, indicating that the secondary silanization process has successfully formed a silicon dioxide shell layer on the surface of the avobenzone-loaded mesoporous silica particles.

[0083] 2. The mesoporous silica particles loaded with avobenzone in Example 1, the functionalized mesoporous silica particles, and the mesoporous silica particles in Comparative Example 5 were characterized by FITR spectroscopy. The successful loading of the UV filter was observed through characteristic functional groups. Figure 2 The FTIR spectra of the mesoporous silicon particles in Comparative Example 5 (a), avobenzone in Example 1, and functionalized mesoporous silicon particles are obtained from... Figure 2 It can be seen that the FTIR spectrum of the functionalized mesoporous silica particles retains the characteristic absorption peaks of avobenzone and mesoporous silica particles, and the peak position of avobenzone does not shift significantly. This indicates that avobenzone has been successfully loaded into the mesoporous silica particles and exists mainly in the form of physical adsorption / embedding without significant chemical bonding. This is beneficial to maintaining its UV absorption activity, that is, the functionalized mesoporous silica particles have been successfully prepared.

[0084] 3. The ultraviolet light absorption properties of avobenzone, avobenzone-loaded mesoporous silica particles, functionalized mesoporous silica particles in Example 1, and mesoporous silica particles in Comparative Example 5 were determined. Specifically, the mass of avobenzone and mesoporous silica particles was controlled to be 2.1% and 97.9% of the functionalized mesoporous silica particles, respectively. The samples were dispersed in a 50% (v / v) propylene glycol solution. 3 mL of the dispersion was placed in an ultraviolet spectrophotometer, and its absorbance in the wavelength range of 280-400 nm was measured. Figure 3 The images show the UV absorption spectra of avobenzone, avobenzone-loaded mesoporous silicon particles, functionalized mesoporous silicon particles from Example 1, and mesoporous silicon particles from Comparative Example 5. Figure 3It can be seen that in the characteristic absorption band of avobenzone (UVA region, 320-400nm), the functionalized mesoporous silicon particles prepared in Example 1 exhibit significant absorption, and the intensity is higher than that of pure avobenzone and avobenzone-loaded mesoporous silicon particles, while the mesoporous silicon particles have almost no absorption. This indicates that the loading and encapsulation process did not destroy the UV absorption function of avobenzone, and the functionalized mesoporous silicon particles have strong absorption capacity in the UVA band, showing enhanced UV protection and ROS suppression potential. Furthermore, the UV light absorption performance of the functionalized mesoporous silicon particles is superior to that of avobenzone-loaded mesoporous silicon particles. The presence of avobenzone indicates that after being coated with a silica shell, the particles form a complete core-shell structure, with changes in their size, morphology, and refractive index. This significantly enhances the particles' ability to scatter ultraviolet light. Furthermore, the silica shell firmly encapsulates avobenzone within the mesopores, forming a physical barrier that effectively prevents the leakage of active molecules in the measurement medium. In contrast, mesoporous silica particles loaded with avobenzone undergo only one loading process, and some avobenzone molecules may be physically adsorbed on the particle surface or in shallow pores. During sample preparation or spectral measurement, these molecules are prone to dissociation, dissolution, or loss, resulting in lower measured absorbance.

[0085] 4. The photocatalytic activity of avobenzone and functionalized mesoporous silica particles in Example 2 was evaluated by measuring the degree of degradation of methylene blue dye in aqueous suspension. Specifically, 0.1 wt% of avobenzone and functionalized mesoporous silica particles were mixed and dispersed with 5 mg / L of methylene blue aqueous solution, respectively. After 3 days of ultraviolet irradiation, the photocatalytic degradation degree of methylene blue (maximum absorption wavelength λmax = 664 nm) was measured using a UV-Vis spectrophotometer. All solutions were centrifuged before measurement to completely remove particles. Figure 4 The photocatalytic activity test results of avobenzone and functionalized mesoporous silica particles in Example 2 are from... Figure 4 It can be seen that, under the same treatment conditions, the treatment group with added avobenzone degraded 3.52 mg / L of methylene blue through photocatalysis, while the treatment group with added functionalized mesoporous silica particles degraded only 0.376 mg / L of methylene blue. This indicates that the loading of mesoporous silica particles and the coating of silica shell reduced the photocatalytic activity of avobenzone by 89.3%. In other words, the functionalized mesoporous silica particles provided by this invention can greatly inhibit the free radicals generated by the photodegradation of UV filters themselves, thus solving the contradiction of "protection-destruction" in traditional UV protection.

[0086] 5. The functionalized mesoporous silica particles prepared in Example 2 were subjected to three-phase contact angle testing and emulsion morphology characterization. Specifically, the functionalized mesoporous silica particles were uniformly dispersed in a hexane solution. The dispersed solution was dropped onto a glass slide. After the hexane evaporated, a particle layer uniformly covering the glass slide was obtained. The particle layer was then placed in caprylic / capric triglyceride, and deionized water was dropped onto the glass slide. The three-phase contact angle of the particles was measured. The functionalized mesoporous silica particles were hand-shaken into an emulsion according to a certain oil-water ratio and particle concentration. The morphology of the resulting emulsion was observed under a microscope. Figure 5 The three-phase contact angle test results of the functionalized mesoporous silicon particles in Example 2 are from... Figure 5 It can be seen that the three-phase contact angle of the functionalized mesoporous silicon particles prepared in Example 2 is 89.6°, indicating that the particles provided by the present invention, which are encapsulated in a silica shell, have near-moderate wettability and can be stably adsorbed at the oil-water interface, which is an ideal property for Pickering emulsifiers.

[0087] Figure 6 The emulsion morphology formed by the functionalized mesoporous silica particles in Example 2 is as follows: Figure 6 It can be seen that the functionalized mesoporous silica particles prepared in Example 2 can form uniform emulsion droplets with a size of about 180 μm, indicating that the functionalized mesoporous silica particles provided by the present invention can successfully prepare stable Pickering emulsions with uniform appearance and droplet size, which have the basic form for practical application.

[0088] 6. Photodegradation Characteristics Test of Photosensitive Active Compounds: The ethanol solutions of photosensitive model substances (astaxanthin and vitamin E) were scanned using a UV-Vis spectrophotometer to determine their absorbance characteristics in the UVA (320-400 nm) and UVB (280-320 nm) bands. Subsequently, astaxanthin and vitamin E caprylic / capric triglyceride oil solutions (both at a concentration of 0.06 mg / mL) were subjected to UVA and UVB irradiation, respectively. Samples were taken periodically, and the changes in absorbance values ​​in the corresponding bands were measured to monitor and compare the photodegradation rates of the two active compounds under UVA and UVB irradiation. Figure 7 The absorption spectra of astaxanthin and vitamin E in the UVA and UVB bands are given by [the relevant data]. Figure 7 It can be seen that different substances have great differences in ultraviolet absorption in the 280-400nm wavelength range. Astaxanthin mainly has a large absorbance value in the UVA band, while vitamin E mainly has a large absorbance value in the UVB band.

[0089] Figure 8 This is a graph showing the degradation rate of astaxanthin under UVA and UVB bands. Figure 9This is a graph showing the degradation rate of vitamin E in the UVA and UVB bands, from... Figure 8 and Figure 9 It is known that astaxanthin degrades faster in the UVA band and vitamin E degrades faster in the UVB band. This means that photosensitive active substances are more likely to degrade in bands with higher absorbance values. Therefore, it is necessary to use UV filters that are specifically matched to different bands.

[0090] 7. The UV protection performance of the functionalized mesoporous silica particle-stabilized emulsion systems prepared in Example 1 (loaded with avobenzone) and Example 3 (loaded with ethylhexyl methoxycinnamate) against photosensitive actives with different light absorption characteristics was evaluated: Astaxanthin, which is sensitive to the UVA band, and vitamin E, which is sensitive to the UVB band, were used as model substances. The model substances were encapsulated in emulsion droplets and irradiated with ultraviolet light to induce photodegradation. The mesoporous silica particle-stabilized emulsion system in Example 1 was denoted as APEs, and the mesoporous silica particle-stabilized emulsion system in Example 3 was denoted as OPEs. Figure 10 The light absorption characteristics of the emulsion systems stabilized by functionalized mesoporous silica particles in Examples 1 and 3 are derived from... Figure 10 It is known that the emulsion system stabilized by functionalized mesoporous silica particles loaded with avobenzone (UVA band filter) has strong absorption in the UVA region, while the emulsion system stabilized by functionalized mesoporous silica particles loaded with ethylhexyl methoxycinnamate (UVB band filter) has strong absorption in the UVB region. This indicates that by changing the type of filter loaded on the particles, the UV absorption characteristics of the entire emulsion system can be customized, realizing the ability to construct protective bands on demand.

[0091] 8. Photostability test of photosensitive active substances: The functionalized mesoporous silica particles prepared in Examples 1 and 3 were dispersed in water to obtain an aqueous phase with a functionalized mesoporous silica particle concentration of 1.5 wt%. Astaxanthin and vitamin E were ultrasonically dispersed in caprylic / capric triglycerides for 3 min to obtain an astaxanthin oil phase and a vitamin E oil phase with a concentration of 0.06 mg / mL. The aqueous and oil phases were combined in pairs and manually shaken for 1 min at a volume ratio of 6:5 to obtain four Pickering emulsions. The emulsion containing astaxanthin was placed in a 365 nm ultraviolet radiation chamber, and the emulsion containing vitamin E was placed in a 313 nm ultraviolet radiation chamber. After 240 h, their color changes were tested to measure the photostability of the samples. Figure 11 The photostability of astaxanthin in the emulsion systems stabilized by functionalized mesoporous silica particles in Examples 1 and 3 is demonstrated. Figure 12 To ensure the photostability of vitamin E in the emulsion systems stabilized by functionalized mesoporous silica particles in Examples 1 and 3, [the following text is incomplete and requires further context: "from..."] Figure 11 and 12It can be seen that astaxanthin exhibits better stability in the functionalized mesoporous silica particle-stabilized emulsion system (APEs) supported by avobenzone (UVA band filter) in Example 1, with a 240-hour UV treatment retention rate of 94%, significantly higher than the stability (49%) in the functionalized mesoporous silica particle-stabilized emulsion system (OPEs) supported by ethylhexyl methoxycinnamate (UVB band filter) in Example 3. Furthermore, the protection efficiency of the OPEs system for vitamin E (91%) is significantly better than that of the APEs system (56.7%). This indicates that the functionalized mesoporous silica particle-stabilized emulsion system (OPEs) supported by UVB band filter can effectively shield UVB radiation and is suitable for protecting photosensitive active materials that are sensitive to UVB. The functionalized mesoporous silica particle-stabilized emulsion system (APEs) supported by UVA band filter, by blocking UVA, is more suitable for protecting photosensitive active materials that are susceptible to UVA degradation.

[0092] Furthermore, the Pickering emulsions prepared in Examples 1 and 2, and the oil phases prepared in Comparative Examples 1 and 2 were placed in an ultraviolet radiation chamber (365 nm). The Pickering emulsions prepared in Examples 3 and 4, and the oil phases prepared in Comparative Examples 3 and 4 were placed in an ultraviolet radiation chamber (313 nm) for a period of time, and their color changes were observed to measure the photostability of the samples. Figure 13 The graphs show the color changes of the Pickering emulsion in Example 1 and the oil phase in Comparative Example 1. Figure 14 The graphs show the color changes of the Pickering emulsion in Example 2 and the oil phase in Comparative Example 2. Figure 15 The graphs show the color changes of the Pickering emulsion in Example 3 and the oil phase in Comparative Example 3. Figure 16 The graphs show the color changes of the Pickering emulsion in Example 4 and the oil phase in Comparative Example 4. Figure 13-16 It can be seen that after ultraviolet radiation, the color change of the Pickering emulsion in Examples 1-4 was not obvious, while the color of the oil phase containing photosensitive active ingredients in Comparative Examples 1-4 all changed significantly. This indicates that the functionalized mesoporous silica particles provided by the present invention, as emulsifiers, played a role in resisting ultraviolet radiation in the Pickering emulsion, thereby protecting the photosensitive active ingredients from ultraviolet degradation and improving their photostability.

[0093] 9. Quantitative determination of photosensitivity of photosensitizing active substances: Preparation of DPPH standard solution: Weigh 0.0100g of analytical grade DPPH powder, add a small amount of anhydrous ethanol to dissolve it, transfer it to a 100mL volumetric flask, and dilute to the mark with anhydrous ethanol to obtain a DPPH standard ethanol solution with a concentration of 0.25mmol / L. Store at 4℃ for later use. Preparation of an astaxanthin-loaded emulsion stabilized by primary silanized mesoporous silica particles: Avobenzone was dispersed in ethanol to form dispersion I with a concentration of 8 mg / mL; hexadecyltrimethylammonium bromide was dispersed in an aqueous ethanol solution (ethanol:water = 2:1, v / v) to form dispersion II with a concentration of 5 mg / mL; dispersion I and dispersion II were mixed at a volume ratio of 1:4 and stirred at 500 rpm for 1 h to obtain a mixture; under the condition of 500 rpm, tetraethyl orthosilicate and 25 wt% ammonia solution were added dropwise to the mixture sequentially (tetraethyl orthosilicate:ammonia solution:mixture = 5:1:1). 65, v / v / v), after the addition was completed, the mixture was stirred at 800 rpm for 3 h, eluted and dried to obtain primary silanized mesoporous silica particles loaded with avobenzone; using these primary silanized mesoporous silica particles loaded with avobenzone as an emulsifier, they were dispersed in water at a concentration of 1.5 wt% to form an aqueous phase; astaxanthin was ultrasonically dispersed in caprylic / capric triglyceride for 3 min to obtain an oil phase with an astaxanthin concentration of 0.06 mg / mL; the aqueous phase and oil phase were mixed at a volume ratio of 6:5 and shaken by hand for 1 min to obtain an emulsion of primary silanized mesoporous silica particles stable with astaxanthin; The astaxanthin-loaded emulsion stabilized by the mesoporous silica particles stabilized by the above-mentioned one-time silanization was taken. The astaxanthin-loaded Pickering emulsion prepared in Example 1 was taken as the functionalized mesoporous silica particle-stabilized astaxanthin-loaded emulsion, and the free astaxanthin solution was used as a control. The three were placed in 20 mL screw-top glass bottles and irradiated in a darkroom UV analyzer (365 nm) to induce photodegradation. At specific time points after irradiation (days 1-10), 5 mL of Pickering emulsion samples were taken, centrifuged (10000 rpm, 5 min) to break the emulsion, and the oil phase containing astaxanthin was separated. The absorbance of astaxanthin was measured at a wavelength of 480 nm using a UV-Vis spectrophotometer, and the absorbance of DPPH was measured at a wavelength of 517 nm. The stability of astaxanthin was evaluated by calculating its retention rate and relative antioxidant rate in different systems. The calculation formula is as follows: Astaxanthin retention rate (%) = A n / A 0×100%(1) Free radical scavenging activity (%) = [ B 0-( B 1- B 2)] / B 0×100(2) Free radical scavenging rate (%) = R n / R 0×100%(3) In equation (1), A 0 represents the absorbance of astaxanthin before it has undergone ultraviolet radiation treatment; An The absorbance of astaxanthin after n days of ultraviolet radiation treatment; In equation (2), B 0 was the control group, and the absorbance was measured after incubation of 2.8 mL of ethanol and 1.2 mL of DPPH solution for 30 min. B 1 is the sample group, and the absorbance value of 0.01g sample solution mixed with 2.8mL ethanol and 1.2mL DPPH ethanol solution and incubated for 30min is recorded. B 2 represents the absorbance of a sample blank, obtained by mixing 0.01g of sample solution with 4mL of ethanol solution and incubating for 30min. In equation (3), R 0 represents the free radical scavenging activity of astaxanthin without UV radiation treatment. R n The free radical scavenging activity of astaxanthin after n days of ultraviolet radiation treatment.

[0094] Figure 17 The astaxanthin retention rate in the Pickering emulsion loaded with astaxanthin in Example 1 after 10 days of UV irradiation. Figure 18 To demonstrate the free radical scavenging activity of astaxanthin in Pickering emulsion loaded with astaxanthin after 10 days of UV irradiation, as in Example 1, the following was determined: Figure 17 and Figure 18 It can be seen that in the emulsion protected by functionalized mesoporous silica particles in Example 1, the astaxanthin retention rate is >94% and the free radical scavenging activity is >80% after 10 days of UV irradiation. In the emulsion protected by mesoporous silica particles with single silanization, the astaxanthin retention rate is about 70% after 10 days of UV irradiation, while the retention rate and free radical scavenging activity of free astaxanthin are both 0% after 10 days of UV irradiation. This indicates that when the functionalized mesoporous silica particles provided by the present invention are used as emulsifiers in Pickering emulsions, they can not only prevent the loss of the content of the encapsulated active ingredients, but also maintain their biological activity (antioxidant properties) under long-term severe light irradiation.

Claims

1. A functionalized mesoporous silicon particle, characterized in that, It includes mesoporous silicon particles and a silica shell coating the surface of the mesoporous silicon particles; wherein, the mesoporous silicon particles are loaded with an ultraviolet filter.

2. The functionalized mesoporous silicon particles according to claim 1, characterized in that, The functionalized mesoporous silicon particles comprise the following raw materials: silicon source, alkaline catalyst, ultraviolet filter, and cationic surfactant.

3. The functionalized mesoporous silicon particles according to claim 2, characterized in that, The ultraviolet filter is selected from UVA band filter or UVB band filter; And / or, the alkaline catalyst is selected from ammonia or organic amines; And / or, the cationic surfactant is selected from at least one of hexadecyltrimethylammonium bromide, hexadecyltrimethylammonium chloride, and tetradecyltrimethylammonium bromide.

4. The method for preparing functionalized mesoporous silicon particles according to claim 2 or 3, characterized in that, Includes the following steps: S1. Disperse the ultraviolet filter in a first solvent to form dispersion I, disperse the cationic surfactant in a second solvent to form dispersion II, and mix dispersion I and dispersion II to obtain a mixture; S2. Add silicon source and alkaline catalyst dropwise to the mixture in sequence, react, and obtain mesoporous silicon particles carrying ultraviolet filter. S3. Disperse the ultraviolet-loaded mesoporous silica particles in water to form dispersion III, and add silicon source and alkaline catalyst in sequence to react and obtain the functionalized mesoporous silica particles. Wherein, the first solvent is selected from C1-C4 alkanols; the second solvent is selected from aqueous solutions of C1-C4 alkanols.

5. The method for preparing functionalized mesoporous silicon particles according to claim 4, characterized in that, In step S1, the concentration of the ultraviolet filter in dispersion I is 6-10 mg / L; the concentration of the cationic surfactant in dispersion II is 4-6 mg / L; and the volume ratio of dispersion I to dispersion II in the mixture is (3-5):

1. And / or, in step S2, the volume ratio of the silicon source, alkaline catalyst and mixture is (4-6): 1: (52-78); And / or, in step S3, the concentration of dispersion III is 1.4-2.2 mg / L; the volume ratio of the silicon source and the alkaline catalyst is (1-2):

1.

6. The use of the functionalized mesoporous silica particles according to any one of claims 1-3 as an emulsifier in the preparation of Pickering emulsions.

7. A Pickering emulsion, characterized in that, Includes aqueous phase and oil phase; The oil phase includes photosensitizing active ingredients and C8-C12 fatty acid triglycerides; The aqueous phase comprises the functionalized mesoporous silicon particles as described in any one of claims 1-3 and water.

8. The Pickering emulsion according to claim 7, characterized in that, The volume ratio of the aqueous phase to the oil phase is (1-1.5):1; And / or, the concentration of the photosensitive active ingredient in the oil phase is 0.06-10 mg / mL; And / or, the concentration of the functionalized mesoporous silicon particles in the aqueous phase is 1wt%-2.5wt%.

9. The method for preparing the Pickering emulsion according to claim 7 or 8, characterized in that, Includes the following steps: The aqueous phase and the oil phase are mixed to obtain the Pickering emulsion.

10. The use of the Pickering emulsion according to claim 7 or 8 in the preparation of photostable cosmetics, pharmaceutical preparations or functional foods.

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