An antioxidant broad-spectrum sunscreen film and a method for preparing the same

Abstract

The application relates to an antioxidant broad-spectrum sunscreen film and a preparation method thereof and relates to the technical field of biological materials. TiO2 and a dispersing agent are added into water, and the pH is adjusted to be alkaline; a cerium sulfate solution is added, then heating is carried out, CeO2 is obtained by hydrolysis of the cerium sulfate, and the CeO2 is deposited on the surface of the TiO2, TiO2@CeO2 nanoparticles are obtained; the TiO2@CeO2 nanoparticles, the dispersing agent and dopamine hydrochloride are added into water, the pH is adjusted to be alkaline, then heating is carried out, the dopamine is coated on the surface of the CeO2, and TiO2@CeO2@PDA nanoparticles are obtained; the TiO2@CeO2@PDA nanoparticles, polydimethylsiloxane, fumed silica, water, an emulsifying agent, a thickening agent, a preservative, hydroxyethyl cellulose and a catalyst are added into water, uniform mixing is carried out, vacuum is drawn, and an antioxidant broad-spectrum sunscreen film is obtained. The sunscreen film prepared by the application has strong antioxidant property, good biocompatibility and a broad-spectrum sunscreen effect.

Description

Technical Field

[0001] This invention relates to the field of biomaterials technology, and more specifically, to an antioxidant broad-spectrum sunscreen film and its preparation method. Background Technology

[0002] Excessive exposure to ultraviolet (UV) radiation increases the risk of skin problems such as sunburn, photoaging, and even skin cancer. UV radiation is divided into three ranges: UVC (200-280 nm), UVB (280-320 nm), and UVA (320-400 nm). Short-wave UVB, which penetrates the epidermis, is a major cause of intracellular DNA damage and sunburn; in the dermis, UVA causes oxidative damage and subsequent DNA damage. Notably, both UVB and UVA can produce excessive reactive oxygen species (ROS), leading to gene mutations and tumorigenicity in the skin.

[0003] Compared to protective clothing or parasols, sunscreen is the most common way for individuals to avoid UV-related skin problems. However, it lacks water resistance, making it unsuitable for certain special scenarios and professions. Furthermore, while the main active ingredients in sunscreen formulas are organic absorbers and inorganic filters, inorganic UV filters such as zinc oxide and titanium dioxide, which have photocatalytic effects, can generate reactive oxygen species after UV exposure, posing some potential risks in terms of efficacy and safety. Summary of the Invention

[0004] This invention provides an antioxidant broad-spectrum sunscreen film and its preparation method. TiO2@CeO2@PDA nanoparticles are encapsulated in a polymer film, which not only meets the requirements for antioxidant and broad-spectrum UV protection but also exhibits virtually no skin permeability.

[0005] According to a first aspect of the present invention, a method for preparing an antioxidant broad-spectrum sunscreen film is provided, comprising the following steps:

[0006] (1) Add TiO2 and dispersant to water and adjust the pH to alkaline; add cerium sulfate solution and then heat to hydrolyze cerium sulfate to obtain CeO2 and deposit it on the surface of TiO2 to obtain TiO2@CeO2 nanoparticles;

[0007] (2) Add the TiO2@CeO2 nanoparticles, dispersant and dopamine hydrochloride obtained in step (1) to water, adjust the pH to alkaline, and then heat to make dopamine hydrochloride self-polymerize to obtain dopamine PDA, and coat it on the CeO2 surface to obtain TiO2@CeO2@PDA nanoparticles.

[0008] (3) Add the TiO2@CeO2@PDA nanoparticles, polydimethylsiloxane, fumed silica, water, emulsifier, thickener, preservative, hydroxyethyl cellulose and catalyst obtained in step (2) to water, mix thoroughly, and then vacuum to obtain an antioxidant broad-spectrum sunscreen film.

[0009] Preferably, in step (1), the heating temperature is 57℃-65℃ and the pH is 9-11.

[0010] Preferably, in step (1), the concentration of the cerium sulfate solution is 0.1 to 0.25 mol / L; and the mass ratio of TiO2 to CeO2 in the TiO2@CeO2 nanoparticles is (95 to 110):(0.2 to 0.7).

[0011] Preferably, in step (3), the mass ratio of the TiO2@CeO2@PDA nanoparticles, polydimethylsiloxane, fumed silica, water, emulsifier, thickener, preservative, hydroxyethyl cellulose and catalyst is (100-125):(65-95):(35-45):(160-200):(15-25):(5-20):(5-25):(10-12.5):(5-10).

[0012] Preferably, in step (3), the polydimethylsiloxane comprises a first polydimethylsiloxane, a second polydimethylsiloxane, and a third polydimethylsiloxane; the first and second polydimethylsiloxanes are PDMS1 and PDMS1' containing C=C bonds, respectively, and the third polydimethylsiloxane is PDMS2 containing Si-H; the polydimethylsiloxanes containing C=C bonds and those containing Si-H bonds undergo hydrosilylation addition reaction under the action of a catalyst; the viscosity of PDMS1 is 9-15 Pa. . The C=C bond content is 0.45–0.55 mmoles / g; the viscosity of PDMS1' is 160–180 Pa. . The C=C bond content is 0.01–0.02 mmoles / g; the viscosity of the PDMS2 is 0.04–0.08 Pa. . The Si-H bond content is 4.15–4.55 mmoles / g.

[0013] Preferably, the mass ratio of the first polydimethylsiloxane, the second polydimethylsiloxane, the third polydimethylsiloxane, and fumed silica is (13-18):(3-6):(2-8):(7-9).

[0014] Preferably, the catalyst is a transition metal catalyst;

[0015] Preferably, the catalyst is at least one of a platinum catalyst, a platinum catalyst, and a nickel catalyst.

[0016] Preferably, in step (2), the heating temperature is 48℃-54℃ and the pH is 8-9.5.

[0017] Preferably, the TiO2 has a particle size of 30–50 nm.

[0018] According to another aspect of the present invention, an antioxidant broad-spectrum sunscreen film prepared by any one of the methods is provided.

[0019] In summary, compared with the prior art, the above-described technical solutions conceived by this invention mainly possess the following technical advantages:

[0020] (1) This invention reduces the photocatalytic activity of TiO2 by coating CeO2 on the outside of TiO2; and utilizes the excellent optical and free radical scavenging properties of PDA to coat PDA on the outside of TiO2@CeO2. Due to the synergistic effect of the three, the ultraviolet absorption effect of the obtained TiO2@CeO2@PDA nanoparticles is better than that of any one of the original components.

[0021] (2) The antioxidant broad-spectrum sunscreen film prepared by this invention has strong adhesion and is not easy to fall off. At the same time, the film has sufficient elasticity during skin movement, which helps to restore the skin's elasticity and rebound.

[0022] (3) The antioxidant broad-spectrum sunscreen film prepared by the present invention has a certain degree of water resistance and is suitable for the needs of some special scenarios and special occupations.

[0023] (4) Compared with inorganic ultraviolet filters such as titanium dioxide, the antioxidant broad-spectrum sunscreen film prepared by this invention has stronger antioxidant properties. In addition, it also has broad-spectrum anti-ultraviolet properties.

[0024] (5) The antioxidant broad-spectrum sunscreen film prepared by this invention can be used to prepare safe and effective sunscreen products using nanotechnology, and has broad application prospects. At the same time, the material has good biocompatibility and will not cause any irritation or sensitization reaction. Attached Figure Description

[0025] Figure 1 The image shows a TEM image of the TiO2@CeO2@PDA nanoparticles and TiO2 described in this invention.

[0026] Figure 2 The image shows the ultraviolet (UV) spectrum of the TiO2@CeO2@PDA nanoparticles prepared in Example 2 of this invention.

[0027] Figure 3The image shows a TGA image of the TiO2@CeO2@PDA nanoparticles prepared in Example 2 of this invention. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0029] This invention discloses a method for preparing an antioxidant broad-spectrum sunscreen film, comprising the following steps:

[0030] (1) Mix TiO2, distilled water and dispersant evenly, heat to 57-65℃, and add pH adjuster to adjust pH to 9-11;

[0031] (2) Add 0.1-0.25 mol / L cerium sulfate solution and 0.1-0.25 mol / L sodium hydroxide using a constant flow pump, adjust the feed rate to maintain pH at 9-11, and continue to react for 2-3 hours under heating conditions;

[0032] (3) The suspension obtained in (2) was centrifuged and washed several times, and then freeze-dried for 24-48 h to obtain TiO2@CeO2 nanoparticles;

[0033] (4) Mix TiO2@CeO2 nanoparticles with distilled water, dispersant, and dopamine hydrochloride evenly, adjust the pH to 8-9.5 with pH adjuster, and react at 48-54℃ for 3-4 hours;

[0034] (5) The suspension obtained in (4) is centrifuged and washed several times, and dried at 90-105℃ for 22-26h to obtain TiO2@CeO2@PDA nanoparticles, wherein the mass ratio of TiO2 to CeO2 is (95-110):(0.2-0.7);

[0035] (6) Mix the nanoparticles, polydimethylsiloxane, fumed silica, distilled water, emulsifier, thickener, preservative, hydroxyethyl cellulose and catalyst obtained in (5) at room temperature, stir evenly, vacuum and place at room temperature for 12-16 hours to obtain an antioxidant and broad-spectrum sunscreen film.

[0036] In some embodiments, the mass ratio of the TiO2@CeO2@PDA nanoparticles, polydimethylsiloxane, fumed silica, distilled water, emulsifier, thickener, preservative, hydroxyethyl cellulose and catalyst is (100-125):(65-95):(35-45):(160-200):(15-25):(5-20):(5-25):(10-12.5):(5-10).

[0037] In some embodiments, the mass ratio of the TiO2@CeO2 nanoparticles, distilled water, dispersant and dopamine hydrochloride is (18-22):(950-1050):(1-1.5):(1.8-2.3).

[0038] In some embodiments, the mass ratio of TiO2, distilled water, dispersant, cerium sulfate, and sodium hydroxide is (1000-1500):(2500-3750):(10-15):(4.7-7.5):(15-25).

[0039] In some embodiments, the TiO2 has a particle size of 30–50 nm.

[0040] In some embodiments, the emulsifier is one or more of FZ-2233 and Pemulen TR-2;

[0041] In some embodiments, the thickener is one or more of carbomer Ultraz 20, DC 9045, and butanediol.

[0042] In some embodiments, the preservative is one or more of phenoxyethanol, sodium chloride, and octyl glycol.

[0043] In some embodiments, the catalyst is one of transition metal catalysts such as platinum catalysts and nickel catalysts.

[0044] The following are specific embodiments.

[0045] Example

[0046] An antioxidant, broad-spectrum sunscreen film, comprising the following steps:

[0047] Step 1: Preparation of TiO2@CeO2 nanoparticles

[0048] 1) Mix 10g TiO2, 25ml distilled water and dispersant evenly, heat to 60℃, and add tris(hydroxymethyl)aminomethane solution to adjust pH to 9-10;

[0049] 2) Add 0.1 mol / L cerium sulfate solution and 0.1 mol / L sodium hydroxide using a constant flow pump, adjust the feed rate to maintain pH = 9-10, and react at 60℃ for 2-3 hours;

[0050] 3) The suspension obtained in 2) was centrifuged and washed several times to obtain TiO2@CeO2 nanoparticles, in which the coating amount of CeO2 was 0.02g;

[0051] Step 2: Preparation of TiO2@CeO2@PDA nanoparticles

[0052] 1) Take 2g of TiO2@CeO2 nanoparticles obtained in step 1 and mix them evenly with 100ml of distilled water, 0.1g of dispersant sodium hexametaphosphate and 0.2g of dopamine hydrochloride. Adjust the pH to 8-9 with tris(hydroxymethyl)aminomethane solution and react at 50℃ for 3-4h.

[0053] 2) The suspension obtained in 1) was centrifuged and washed several times to obtain TiO2@CeO2@PDA nanoparticles;

[0054] Step 3: Preparation of an antioxidant, broad-spectrum sunscreen film

[0055] Take 2g of TiO2@CeO2@PDA nanoparticles obtained in step 2, 1.7g of polydimethylsiloxane, 0.9g of fumed silica, 0.2g of KSG-240 emulsifier, 3.8g of water, 0.4g of carbomer thickener, 0.1g of preservative, 0.45g of hydroxyethyl cellulose, and 0.2g of platinum catalyst, mix and stir evenly at room temperature, vacuum and place at room temperature for 12-16h to obtain an antioxidant, broad-spectrum sunscreen film.

[0056] Examples 1-16 differ from Examples 1 in that the amounts of CeO2 coating, dopamine hydrochloride, TiO2@CeO2@PDA, and catalyst are different, but the masses of other components are the same as in Examples 1-16, as shown in Table 1.

[0057] Table 1 Parameter Table for Embodiments

[0058]

[0059] Test Implementation Examples

[0060] Figure 1 These are TEM images of the TiO2@CeO2@PDA nanoparticles and TiO2 described in this invention. Figure 1 It can be seen that TiO2 is prone to aggregation, but after modification, the aggregation phenomenon of TiO2@CeO2@PDA nanoparticles is significantly reduced.

[0061] Table 2 shows the water vapor transmission rate, water retention, skin irritation, and SPF value of the materials obtained in Examples 1-16 of this invention.

[0062]

[0063]

[0064] Table 2 shows that, except for Examples 9 and 13 which caused slight redness of the skin, the materials obtained in the other Examples 1-16 were non-irritating to the skin. The material obtained in Example 2 had the best water vapor transmission rate, at 3210 g / m².24h; the material obtained in Example 9 had the worst water vapor transmission rate, at 1810 g / m².24h. Secondly, the Sun Protection Factor (SPF) is a key evaluation indicator for sunscreens. Table 2 shows the SPF values ​​of sunscreen films with different contents of TiO₂@CeO₂@PDA nanoparticles. It can be seen that when the CeO₂ coating amount is 0.02 g, the dopamine hydrochloride content is 0.2 g, and the TiO₂@CeO₂@PDA nanoparticle content is 2 g, the material has the highest SPF. In summary, the material obtained in Example 2 has the best breathability, gentleness, and UV absorption effect.

[0065] Figure 2 The images show the ultraviolet spectra of the TiO2, TiO2@CeO2 and TiO2@CeO2@PDA nanoparticles described in this invention (where the TiO2@CeO2 and TiO2@CeO2@PDA nanoparticles were prepared in Example 2).

[0066] To verify the UV absorption capabilities of TiO2, TiO2@CeO2, and TiO2@CeO2@PDA nanoparticles, the UV-Vis absorption spectrum of the aqueous dispersion of the nanoparticles was used for characterization. Figure 2 It can be seen that the three nanoparticles exhibit strong and broad absorption peaks in the UV region of 280-450nm, and TiO2@CeO2@PDA nanoparticles have the highest absorbance and the best UV absorption effect.

[0067] Figure 3 The TGA image is of the material obtained in Example 2 of this invention.

[0068] Thermogravimetric analysis (TGA) is a thermal analysis technique that measures the relationship between the mass of a sample and temperature change under programmed temperature control. It can be used to study the thermal stability and composition of materials. Figure 3 As can be seen, the TiO2@CeO2@PDA nanoparticles experience significant weight loss due to the degradation of PDA and CeO2. The content of coated PDA and CeO2 can be estimated using TGA curves. The calculation results are as follows: Figure 3The weight loss was 2.95%, indicating that the present invention successfully synthesized TiO2@CeO2@PDA nanoparticles.

[0069] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A process for the preparation of an antioxidant, broad spectrum sunscreen film, characterized in that, Includes the following steps: (1) Add TiO2 and dispersant to water and adjust the pH to alkaline; Add cerium sulfate solution and then heat to hydrolyze cerium sulfate to obtain CeO2, which is then deposited on the surface of TiO2 to obtain TiO2@CeO2 nanoparticles; (2) Add the TiO2@CeO2 nanoparticles, dispersant and dopamine hydrochloride obtained in step (1) to water, adjust the pH to alkaline, and then heat to make dopamine hydrochloride self-polymerize to obtain dopamine, and coat it on the CeO2 surface to obtain TiO2@CeO2@PDA nanoparticles. (3) Add the TiO2@CeO2@PDA nanoparticles, polydimethylsiloxane, fumed silica, water, emulsifier, thickener, preservative, hydroxyethyl cellulose and catalyst obtained in step (2) to water, mix thoroughly, and then vacuum to obtain an antioxidant broad-spectrum sunscreen film. The polydimethylsiloxane comprises a first polydimethylsiloxane, a second polydimethylsiloxane, and a third polydimethylsiloxane; the first and second polydimethylsiloxanes are PDMS1 and PDMS1' containing C=C bonds, respectively, and the third polydimethylsiloxane is PDMS2 containing Si-H; the polydimethylsiloxanes containing C=C bonds and those containing Si-H bonds undergo hydrosilylation addition reaction under the action of a catalyst; the viscosity of PDMS1 is 9~15 Pa. . The C=C bond content is 0.45~0.55 mmoles / g; the viscosity of PDMS1' is 160~180 Pa. . The C=C bond content is 0.01~0.02 mmoles / g; the viscosity of the PDMS2 is 0.04~0.08 Pa. . The Si-H bond content is 4.15~4.55 mmoles / g; The catalyst is a transition metal catalyst.

2. The method of claim 1, wherein the antioxidant broad spectrum sunscreen film is prepared by the steps of: In step (1), the heating temperature is 57℃-65℃ and the pH is 9-11.

3. The method for preparing the antioxidant broad-spectrum sunscreen film as described in claim 1, characterized in that, In step (1), the concentration of the cerium sulfate solution is 0.1~0.25 mol / L; the mass ratio of TiO2 to CeO2 in the TiO2@CeO2 nanoparticles is (95~110):(0.2~0.7).

4. The method for preparing the antioxidant broad-spectrum sunscreen film as described in claim 1, characterized in that, In step (3), the mass ratio of TiO2@CeO2@PDA nanoparticles, polydimethylsiloxane, fumed silica, water, emulsifier, thickener, preservative, hydroxyethyl cellulose and catalyst is (100~125):(65~95):(35~45):(160~200):(15~25):(5~20):(5~25):(10~12.5):(5~10).

5. The method for preparing the antioxidant broad-spectrum sunscreen film as described in claim 1, characterized in that, The mass ratio of the first polydimethylsiloxane, the second polydimethylsiloxane, the third polydimethylsiloxane and fumed silica is (13~18):(3~6):(2~8):(7~9).

6. The method for preparing the antioxidant broad-spectrum sunscreen film as described in claim 1, characterized in that, The catalyst is at least one of a platinum catalyst and a nickel catalyst.

7. The method for preparing the antioxidant broad-spectrum sunscreen film as described in claim 1, characterized in that, In step (2), the heating temperature is 48℃-54℃ and the pH is 8-9.

5.

8. The method for preparing the antioxidant broad-spectrum sunscreen film as described in claim 1, characterized in that, The TiO2 has a particle size of 30~50 nm.

9. An antioxidant broad-spectrum sunscreen film prepared by any one of claims 1-8.

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