Radiation shielding covering and preparation method and application thereof

Abstract

The invention provides a radiation shielding covering and a preparation method and application thereof. The radiation shielding covering provided by the invention comprises carrier cream and bismuth oxide, wherein the mass content of the bismuth oxide in the radiation shielding covering is 5-85%; the carrier cream is prepared from ethylparaben, xanthan gum, cetostearyl alcohol, albolene, lauryl sodium sulfate, phenoxyethanol and deionized water; the mass ratio of the ethylparaben to the xanthan gum to the cetostearyl alcohol to the white vaseline to the lauryl sodium sulfate to the phenoxyethanol is 1 to (0.4 to 0.6) to (7.5 to 8.5) to (7.5 to 8.5) to (0.9 to 1.1) to (0.9 to 1.1); the mass content of the deionized water in the carrier cream is 80.5%-93.5%. Bismuth oxide is selected as a radiation shielding component and acts together with the carrier cream with specific components, so that the radiation shielding effect of the radiation shielding covering is improved.

Description

Technical Field

[0001] This invention belongs to the field of radiation shielding materials technology, specifically relating to a radiation shielding covering and its preparation method. Background Technology

[0002] Ionizing radiation has been widely used in various fields such as medicine, nuclear energy, industry, and scientific research. However, while ionizing radiation has its effects, it can also cause damage to non-target areas. Therefore, a series of radiation shielding materials have been developed to block or attenuate the harmful effects of ionizing radiation on the human body, equipment, or the environment. Traditional radiation shielding protective equipment such as lead aprons and lead gloves can effectively shield radiation, but their bulkiness and rigidity can restrict the movement of the hands and other parts of the body, thus affecting the tactile sensation and operational precision of surgical personnel. Moreover, if traditional lead radiation shielding materials are damaged, lead leakage can occur, causing pollution to the human body and the environment.

[0003] Existing technologies include radiation shielding covers prepared by mixing barium sulfate and other substances, such as barium sulfate, with a cream as a radiation shielding component instead of lead. Direct contact with the skin does not pose a significant risk of irritation or poisoning, and the radiation shielding cream can be applied directly to exposed areas without hindering joint movement or tactile sensation. It conforms to the curves and folds of the skin, eliminating any blind spots. While barium sulfate has high safety, its radiation shielding effectiveness is limited. Therefore, there is an urgent need for a radiation shielding cover with superior radiation shielding performance. Summary of the Invention

[0004] The purpose of this invention is to provide a radiation shielding covering, its preparation method, and its application. The radiation shielding covering provided by this invention has good radiation shielding effect.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a radiation shielding covering, comprising a carrier cream and bismuth oxide, wherein the mass content of bismuth oxide in the radiation shielding covering is 5%~85%; the carrier cream comprises ethylparaben, xanthan gum, cetearyl alcohol, white petrolatum, sodium lauryl sulfate, phenoxyethanol, and deionized water; the mass ratio of ethylparaben, xanthan gum, cetearyl alcohol, white petrolatum, sodium lauryl sulfate, and phenoxyethanol is 1:(0.4~0.6):(7.5~8.5):(7.5~8.5):(0.9~1.1):(0.9~1.1); and the mass content of deionized water in the carrier cream is 80.5%~93.5%.

[0006] Preferably, the bismuth oxide content in the radiation shielding covering is 45% to 85% by mass.

[0007] Preferably, the bismuth oxide content in the radiation shielding covering is 65% to 85% by mass.

[0008] The present invention also provides a method for preparing the radiation shielding covering described in the above technical solution, comprising the following steps: Ethylparaben, xanthan gum, and deionized water were first mixed to obtain an aqueous phase. Cetearyl alcohol, white petrolatum, and sodium lauryl sulfate were mixed in a second step to obtain the oil phase. The aqueous phase and the oil phase are mixed in a third process, and then mixed with phenoxyethanol in a fourth process to obtain a carrier cream. The carrier cream and bismuth oxide are mixed in a fifth step to obtain a radiation shielding coating.

[0009] Preferably, the first mixing involves first adding ethylparaben to deionized water, and then adding xanthan gum.

[0010] Preferably, the temperatures of the first mixture, the second mixture, and the third mixture are independently 80~90°C; the temperature of the fourth mixture is 40~60°C.

[0011] Preferably, after the fourth mixing, deionized water is added for dilution to obtain a carrier cream.

[0012] Preferably, the temperature of the deionized water is 95~100℃.

[0013] Preferably, the first mixing, second mixing, third mixing, fourth mixing and fifth mixing are carried out under stirring conditions; the stirring speed of the first mixing is 180~220 rpm / min; the stirring speed of the second mixing, third mixing and fourth mixing is independently 500~800 rpm / min; the stirring speed of the fifth mixing is 2500~3500 rpm / min.

[0014] The present invention also provides the application of the radiation shielding covering described in the above technical solution or the radiation shielding covering prepared according to the preparation method described in the above technical solution in shielding X-rays and strontium-90 rays.

[0015] This invention provides a radiation shielding covering, comprising a carrier cream and bismuth oxide, wherein the mass content of bismuth oxide in the radiation shielding covering is 5%~85%; the carrier cream comprises ethylparaben, xanthan gum, cetearyl alcohol, white petrolatum, sodium lauryl sulfate, phenoxyethanol, and deionized water; the mass ratio of ethylparaben, xanthan gum, cetearyl alcohol, white petrolatum, sodium lauryl sulfate, and phenoxyethanol is 1:(0.4~0.6):(7.5~8.5):(7.5~8.5):(0.9~1.1):(0.9~1.1); and the mass content of deionized water in the carrier cream is 80.5%~93.5%. This invention selects bismuth oxide as the radiation shielding component. The high atomic number of bismuth oxide significantly reduces radiation transmittance through the photoelectric effect and Compton scattering mechanism, thereby improving the radiation shielding effect of the radiation shielding cover. Furthermore, bismuth oxide has a high density, which can further increase the radiation attenuation coefficient, thus improving the radiation shielding effect. White petrolatum and the emulsifying stabilizer cetearyl alcohol are high-melting-point hydrophobic oil phases. Combined with the highly hydrophilic oil-in-water (O / W) emulsifier sodium dodecyl sulfate, they can form a uniform and stable system to support bismuth oxide. Xanthan gum is a hydrophilic thickening and stabilizing agent. After fully swelling in the aqueous phase, it can form a network structure, inhibiting oil-water separation, making the cream texture uniform and delicate, and maintaining the stability of the cream. Ethylparaben has an inhibitory effect on bacteria and fungi, while phenoxyethanol has an inhibitory effect on Gram-positive bacteria, Gram-negative bacteria, and fungi. Both phenoxyethanol and ethylparaben are water-soluble preservative systems, which can prevent the carrier cream from becoming unstable due to microbial contamination. Experimental results show that the radiation shielding covering provided by this invention has good morphological stability, and there is no demulsification or stratification after high-temperature and low-temperature treatment; it has high safety, with a pH value of 8.2~8.6, and is non-irritating to the skin; it has good radiation shielding effect against mixed rays and X-rays generated by Strontium-90 radioactive sources. Attached Figure Description

[0016] Figure 1 The figures show the pH values ​​of the radiation shielding coverings prepared in Examples 5-10 of this invention. Figure 2 These are images showing the appearance of the carrier cream and radiation shielding cover prepared in Example 5 of the present invention at different application thicknesses; Figure 3 This is a schematic diagram of the radiation shielding rate determination method in the physical shielding experiment of this invention; Figure 4 Radiation shielding efficiency of the carrier cream prepared in Example 5 of the present invention and the radiation shielding coatings prepared in Examples 1-6 and Comparative Examples 1-6 for mixed rays generated by a strontium-90 radioactive source under different coating thicknesses; Figure 5A schematic diagram illustrating the operation of cell cloning experiments for the blank group, the carrier cream prepared in Example 5 of the present invention, and the radiation shielding coverings prepared in Example 5 and Comparative Example 5; Figure 6 The radiation shielding effect of the blank group, the carrier cream prepared in Example 5 of the present invention, and the radiation shielding covering prepared in Example 5 and Comparative Example 5 on X-rays on mouse skin melanoma (B16) cells is shown in the figure. Figure 7 for Figure 6 A statistical diagram showing the clonogenic results of mouse skin melanoma (B16) cells. Figure 8 The radiation shielding effect of the blank group, the carrier cream prepared in Example 5 of the present invention, and the radiation shielding cover prepared in Example 5 and Comparative Example 5 on X-rays on human immortalized epidermal (HaCaT) cells is shown in the figure. Figure 9 for Figure 8 A statistical diagram of the clonogenic formation of human immortalized epidermal (HaCaT) cells; Figure 10 The images show cell viability detection of mouse skin melanoma (B16) cells after X-ray irradiation for 3 days, 5 days, and 3 days, respectively, using the carrier cream prepared in Example 5 of this invention and the radiation shielding cover prepared in Example 5. Figure 11 The images show cell viability detection of human immortalized epidermal (HaCaT) cells after X-ray irradiation for 3 days, 5 days, and 3 days, respectively, after using the carrier cream prepared in Example 5 of this invention and the radiation shielding cover prepared in Example 5. Figure 12 The images show the appearance of the radiation shielding coverings prepared in Examples 5-10 and Comparative Example 7. Figure 13 The radiation shielding effect of the blank group, the carrier cream prepared in Example 5 of the present invention, and the radiation shielding coverings prepared in Examples 5-10 on X-rays on human immortalized epidermal (HaCaT) cells is shown in the figure. Figure 14 for Figure 13 A statistical diagram of the clonogenic formation of human immortalized epidermal (HaCaT) cells; Figure 15 Cell viability assay of human immortalized epidermal (HaCaT) cells after 3 days of X-ray irradiation, using the carrier cream prepared in Example 5 of this invention and the radiation shielding cover prepared in Examples 5-10. Figure 16Damage images of mice after X-ray irradiation for 18 and 28 days following application of the blank group, the carrier cream prepared in Example 5 of this invention, and the radiation shielding coverings prepared in Examples 5 and 10 to the legs; Figure 17 HE pathological sections of mice after being irradiated with X-rays for 40 days, including the blank group, the carrier cream prepared in Example 5 of the present invention, and the radiation shielding coverings prepared in Examples 5 and 10. Figure 18 The blank group, the carrier cream prepared in Example 5 of the present invention, and the radiation shielding cover prepared in Examples 5 and 10 were used on the legs of mice, and the skin damage score curve of the legs after X-ray irradiation was obtained. Figure 19 Damage images of mice after irradiation with strontium-90 mixed rays for 19, 21, 36, and 47 days following application of the blank group, the carrier cream prepared in Example 5 of this invention, and the radiation shielding coverings prepared in Examples 5 and 10 to the back of mice. Detailed Implementation

[0017] This invention provides a radiation shielding covering, comprising a carrier cream and bismuth oxide, wherein the mass content of bismuth oxide in the radiation shielding covering is 5%~85%; the carrier cream comprises ethylparaben, xanthan gum, cetearyl alcohol, white petrolatum, sodium lauryl sulfate, phenoxyethanol, and deionized water; the mass ratio of ethylparaben, xanthan gum, cetearyl alcohol, white petrolatum, sodium lauryl sulfate, and phenoxyethanol is 1:(0.4~0.6):(7.5~8.5):(7.5~8.5):(0.9~1.1):(0.9~1.1); and the mass content of deionized water in the carrier cream is 80.5%~93.5%.

[0018] The radiation shielding covering provided by this invention includes bismuth oxide, wherein the mass content of bismuth oxide in the radiation shielding covering is 5% to 85%, preferably 45% to 85%, and more preferably 65% ​​to 85%. The higher atomic number of bismuth oxide can improve radiation shielding performance through the photoelectric effect and Compton scattering mechanism, and the high density of bismuth oxide can increase the upper limit of the concentration of bismuth oxide, a radiation shielding component, in the carrier cream, thereby enhancing the radiation shielding effect of the radiation shielding covering.

[0019] The radiation shielding cover provided by this invention also includes a carrier cream. In one embodiment of this invention, the mass content of the carrier cream in the radiation shielding cover can be 15% to 95%.

[0020] In this invention, the carrier cream comprises ethylparaben, xanthan gum, cetearyl alcohol, white petrolatum, sodium lauryl sulfate, phenoxyethanol, and deionized water. Ethylparaben is a water-soluble preservative that inhibits bacteria and fungi and can be uniformly distributed in the aqueous phase, thus preventing the carrier cream from becoming unstable due to microbial contamination. Xanthan gum is a hydrophilic polysaccharide and a hydrophilic thickener. After fully swelling in the aqueous phase, it forms a network structure, maintaining the stability of the carrier cream, resulting in a uniform and delicate texture that is less prone to phase separation. Furthermore, xanthan gum enhances the thixotropy of the carrier cream, ensuring that the system maintains a certain consistency after adding water, preventing water-oil separation and improving the stability of the carrier cream. In this invention, cetearyl alcohol is a co-emulsifier, also known as an emulsion stabilizer. It can also form a liquid crystal structure, helping to maintain the consistency and uniformity of the carrier cream. It often works synergistically with emulsifiers to reduce the interfacial tension between the oil and water phases, promoting the formation of a uniform and stable emulsion. In this invention, white petrolatum is an oil-based occlusive moisturizing component, the main component of the oil phase, and also has functions such as shaping, protection, and system stabilization. In this invention, sodium dodecyl sulfate is a potent anionic surfactant. As a highly hydrophilic oil-in-water (O / W) emulsifier, it has excellent emulsifying and dispersing abilities. The stable emulsion system formed with cetearyl alcohol can stabilize the oil phase, prevent precipitation due to water addition, and support more bismuth oxide. In this invention, phenoxyethanol is a water-soluble preservative. Phenoxyethanol has an inhibitory effect on Gram-positive bacteria, Gram-negative bacteria and fungi. It can be evenly distributed in the aqueous phase. After adding water, it will not disrupt the balance of the preservative system, thereby preventing the carrier cream from becoming unstable due to microbial contamination.

[0021] In this invention, the mass ratio of ethylparaben, xanthan gum, cetearyl alcohol, white petrolatum, sodium lauryl sulfate, and phenoxyethanol is 1:(0.4~0.6):(7.5~8.5):(7.5~8.5):(0.9~1.1):(0.9~1.1); as one embodiment of this invention, the mass ratio of ethylparaben, xanthan gum, cetearyl alcohol, white petrolatum, sodium lauryl sulfate, and phenoxyethanol can be... The mass ratios of ethylparaben, xanthan gum, cetearyl alcohol, white petrolatum, sodium lauryl sulfate, and phenoxyethanol in the carrier cream are 1:0.5:8:8:1:1, 1:0.4:7.8:8.3:1:1, 1:0.5:8:7.9:1.1:0.9, 1:0.6:8.2:8:1.1:1, or 1:0.5:8.3:7.7:0.9:1. In embodiments of the present invention, the mass ratio of ethylparaben, xanthan gum, cetearyl alcohol, white petrolatum, sodium lauryl sulfate, and phenoxyethanol is 1:0.5:8:8:1:1. In the present invention, by controlling the mass ratio of ethylparaben, xanthan gum, cetearyl alcohol, white petrolatum, sodium lauryl sulfate, and phenoxyethanol in the carrier cream within the above range, the carrying capacity of bismuth oxide can be improved, which is beneficial to improving the dispersibility of bismuth oxide, forming a uniform protective film, thereby improving the shielding performance of the radiation shielding cover.

[0022] In this invention, the deionized water content in the carrier cream is 80.5% to 93.5%, preferably 90.25% to 93.5%. As one embodiment of this invention, the deionized water content in the carrier cream can specifically be 80.5%, 81%, 83%, 85%, 87%, 89%, 90.25%, 91%, 93%, or 93.5%. Water-soluble components in the cream rely on deionized water for dissolution, while fat-soluble components also need to be uniformly dispersed in the aqueous phase. Controlling the deionized water content within the above range ensures that the components are fully dissolved and uniformly dispersed. The carrier cream in this invention achieves different viscosities by adjusting the deionized water content, thereby carrying a larger amount of bismuth oxide when the water content is high. This also prevents the obtained radiation shielding coating from being too thin for thick application or too dry for spread, reducing operational difficulty and facilitating the formation of a uniform protective film, thus improving the shielding performance of the radiation shielding coating.

[0023] This invention improves the radiation shielding effect of radiation shielding coverings by selecting bismuth oxide with high atomic number and high density as the radiation shielding component, which works together with a carrier cream of specific components.

[0024] The present invention also provides a method for preparing the radiation shielding covering described in the above technical solution, comprising the following steps: Ethylparaben, xanthan gum, and deionized water were first mixed to obtain an aqueous phase. Cetearyl alcohol, white petrolatum, and sodium lauryl sulfate were mixed in a second step to obtain the oil phase. The aqueous phase and the oil phase are mixed in a third process, and then mixed with phenoxyethanol in a fourth process to obtain a carrier cream. The carrier cream and bismuth oxide are mixed in a fifth step to obtain a radiation shielding coating.

[0025] This invention does not have any special restrictions on the source of the raw materials used; they can be commercially available.

[0026] In this invention, ethylparaben, xanthan gum, and deionized water are first mixed to obtain an aqueous phase. As one embodiment of this invention, the mass ratio of deionized water to ethylparaben can be (80~81):1 or (80.5~81):1.

[0027] In this invention, the temperature of the first mixing is preferably 80~90℃, more preferably 85~90℃; the first mixing is preferably carried out under stirring conditions, and the stirring speed of the first mixing is preferably 180~220 rpm / min, more preferably 200~220 rpm / min.

[0028] In one embodiment of the present invention, the first mixing may involve first adding ethylparaben to deionized water, and then adding xanthan gum.

[0029] In this invention, cetearyl alcohol, white petrolatum, and sodium lauryl sulfate are mixed in a second process to obtain an oil phase. In this invention, the temperature of the second mixing is preferably 80-90°C, more preferably 85-90°C; the second mixing is preferably carried out under stirring conditions, and the stirring speed of the second mixing is preferably 500-800 rpm / min, more preferably 700-800 rpm / min.

[0030] After obtaining the aqueous phase and the oil phase, the present invention performs a third mixing of the aqueous phase and the oil phase, and then performs a fourth mixing with phenoxyethanol to obtain a carrier cream. In the present invention, the temperature of the third mixing is preferably 80-90°C, more preferably 85-90°C; the third mixing is preferably carried out under stirring conditions, the stirring speed of the third mixing is preferably 500-800 rpm / min, more preferably 700-800 rpm / min, and the stirring time of the third mixing is preferably 30-60 min. In the present invention, the temperature of the fourth mixing is preferably 40-60°C, more preferably 50-60°C; the fourth mixing is preferably carried out under stirring conditions, the stirring speed of the fourth mixing is preferably 500-800 rpm / min, more preferably 700-800 rpm / min.

[0031] In one embodiment of the present invention, after the fourth mixing, deionized water can be added for dilution to obtain a carrier cream. In this invention, the total amount of deionized water added is based on the total deionized water content in the carrier cream.

[0032] In this invention, the temperature of the deionized water used for dilution is preferably 95~100℃, more preferably 100℃.

[0033] This invention, by adding an appropriate amount of deionized water for dilution, can accommodate a larger amount of bismuth oxide and prevent the obtained radiation shielding cover from being too thin to be applied thickly, too fluid to remain on the skin surface, or too dry to be spread. This reduces the difficulty of operation, facilitates the formation of a uniform protective film, and improves the shielding performance of the radiation shielding cover.

[0034] After obtaining the carrier cream, the present invention performs a fifth mixing of the carrier cream and bismuth oxide to obtain a radiation shielding coating. In the present invention, the temperature of the fifth mixing is preferably 10~30℃, more preferably 20~30℃; the fifth mixing is preferably carried out under stirring conditions, the stirring speed of the fifth mixing is preferably 2500~3500 rpm / min, more preferably 3000~3500 rpm / min, and the stirring time of the fifth mixing is preferably 10~15 min, more preferably 12~15 min.

[0035] The radiation shielding cover prepared by the above preparation method of the present invention is not difficult to thicken due to being too thin, or difficult to spread due to being too dry, which is conducive to forming a uniform protective film and improves the radiation shielding effect of the radiation shielding cover.

[0036] This invention also provides the application of the radiation shielding covering described in the above-described technical solutions, or the radiation shielding covering prepared according to the preparation method described in the above-described technical solutions, in shielding X-rays and strontium-90 rays. This invention does not impose any special limitations on the applications described; any application methods well-known to those skilled in the art can be used.

[0037] The technical solutions of this invention will be clearly and completely described below with reference to the embodiments thereof. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0038] Example 1 The radiation shielding cover is composed of a carrier cream and bismuth oxide, wherein the mass content of bismuth oxide in the radiation shielding cover is 5%; the carrier cream is composed of the following components: ethylparaben, xanthan gum, cetearyl alcohol, white petrolatum, sodium lauryl sulfate, phenoxyethanol, and deionized water; the mass ratio of ethylparaben, xanthan gum, cetearyl alcohol, white petrolatum, sodium lauryl sulfate, and phenoxyethanol is 1:0.5:8:8:1:1; the mass content of deionized water in the carrier cream is 90.25%.

[0039] Methods for preparing radiation shielding coverings: Ethylparaben, xanthan gum, and deionized water were first mixed. 10g of ethylparaben was added to 805g of deionized water, followed by 5g of xanthan gum. The mixture was heated to 85℃ and stirred at 200rpm / min to obtain the aqueous phase. Cetearyl alcohol, white petrolatum, and sodium lauryl sulfate were mixed in a second step. 80g of cetearyl alcohol (C1618 alcohol), 80g of white petrolatum, and 10g of sodium lauryl sulfate (K12 emulsifier) ​​were heated to 85°C and stirred at a stirring speed of 700 rpm / min to obtain the oil phase. The aqueous phase and the oil phase are mixed for the third time. The aqueous phase and the oil phase are heated to 85°C and stirred at a stirring speed of 700 rpm / min for 30 min. Then, they are mixed with phenoxyethanol for the fourth time. The mixture is cooled to 50°C, and 10 g of phenoxyethanol is added and stirred at a stirring speed of 700 rpm / min. The mixture is cooled to room temperature, and 500 g of the mixture is added to 500 g of deionized water at 100°C and then simply stirred and diluted to obtain the carrier cream. The carrier cream and bismuth oxide are mixed for the fifth time. 95g of the carrier cream is taken and 5g of bismuth oxide is added. The mixture is stirred at room temperature (25°C) at a speed of 3000rpm / min for 15min to obtain the radiation shielding cover. The product is then discharged, filled, and packaged.

[0040] Example 2 The difference from the radiation shielding cover in Example 1 is that "the mass content of bismuth oxide in the radiation shielding cover is 5%" is replaced with "the mass content of bismuth oxide in the radiation shielding cover is 15%".

[0041] The difference from the method for preparing the radiation shielding cover in Example 1 is that, when mixing the carrier cream and bismuth oxide for the fifth time, "take 95g and add 5g of bismuth oxide" is replaced with "take 85g and add 15g of bismuth oxide".

[0042] Example 3 The difference from the radiation shielding cover in Example 1 is that "the mass content of bismuth oxide in the radiation shielding cover is 5%" is replaced with "the mass content of bismuth oxide in the radiation shielding cover is 25%".

[0043] The difference from the method for preparing the radiation shielding cover in Example 1 is that, when mixing the carrier cream and bismuth oxide for the fifth time, "take 95g and add 5g of bismuth oxide" is replaced with "take 75g and add 25g of bismuth oxide".

[0044] Example 4 The difference from the radiation shielding cover in Example 1 is that "the mass content of bismuth oxide in the radiation shielding cover is 5%" is replaced with "the mass content of bismuth oxide in the radiation shielding cover is 35%".

[0045] The difference from the method for preparing the radiation shielding cover in Example 1 is that, when mixing the carrier cream and bismuth oxide for the fifth time, "take 95g and add 5g of bismuth oxide" is replaced with "take 65g and add 35g of bismuth oxide".

[0046] Example 5 The difference from the radiation shielding cover in Example 1 is that "the mass content of bismuth oxide in the radiation shielding cover is 5%" is replaced with "the mass content of bismuth oxide in the radiation shielding cover is 45%"; and "the mass content of deionized water in the carrier cream is 90.25%" is replaced with "the mass content of deionized water in the carrier cream is 93.5%".

[0047] The difference from the method for preparing the radiation shielding cover in Example 1 is that, when mixing the carrier cream and bismuth oxide for the fifth time, "take 95g and add 5g of bismuth oxide" is replaced with "take 55g and add 45g of bismuth oxide"; before obtaining the carrier cream, "take 500g and add 500g of deionized water at 100°C and then perform simple stirring, mixing and dilution" is replaced with "take 500g and add 1000g of deionized water at 100°C and then perform simple stirring, mixing and dilution to obtain the carrier cream".

[0048] Example 6 The difference from the radiation shielding cover in Example 5 is that "the mass content of bismuth oxide in the radiation shielding cover is 45%" is replaced with "the mass content of bismuth oxide in the radiation shielding cover is 55%".

[0049] The difference from the method for preparing the radiation shielding cover in Example 5 is that, when mixing the carrier cream and bismuth oxide for the fifth time, "take 55g and add 45g of bismuth oxide" is replaced with "take 45g and add 55g of bismuth oxide".

[0050] Example 7 The difference from the radiation shielding cover in Example 5 is that "the mass content of bismuth oxide in the radiation shielding cover is 45%" is replaced with "the mass content of bismuth oxide in the radiation shielding cover is 65%".

[0051] The difference from the method for preparing the radiation shielding cover in Example 5 is that, when mixing the carrier cream and bismuth oxide for the fifth time, "take 55g and add 45g of bismuth oxide" is replaced with "take 35g and add 65g of bismuth oxide".

[0052] Example 8 The difference from the radiation shielding cover in Example 5 is that "the mass content of bismuth oxide in the radiation shielding cover is 45%" is replaced with "the mass content of bismuth oxide in the radiation shielding cover is 70%".

[0053] The difference from the method for preparing the radiation shielding cover in Example 5 is that, when mixing the carrier cream and bismuth oxide for the fifth time, "take 55g and add 45g of bismuth oxide" is replaced with "take 30g and add 70g of bismuth oxide".

[0054] Example 9 The difference from the radiation shielding cover in Example 5 is that "the mass content of bismuth oxide in the radiation shielding cover is 45%" is replaced with "the mass content of bismuth oxide in the radiation shielding cover is 80%".

[0055] The difference from the method for preparing the radiation shielding cover in Example 5 is that, when mixing the carrier cream and bismuth oxide for the fifth time, "take 55g and add 45g of bismuth oxide" is replaced with "take 20g and add 80g of bismuth oxide".

[0056] Example 10 The difference from the radiation shielding cover in Example 5 is that "the mass content of bismuth oxide in the radiation shielding cover is 45%" is replaced with "the mass content of bismuth oxide in the radiation shielding cover is 85%".

[0057] The difference from the method for preparing the radiation shielding cover in Example 5 is that, when mixing the carrier cream and bismuth oxide for the fifth time, "take 55g and add 45g of bismuth oxide" is replaced with "take 15g and add 85g of bismuth oxide".

[0058] Comparative Example 1 The difference between this and the radiation shielding cover and its preparation method in Example 1 is that all "bismuth oxide" is replaced with "barium sulfate".

[0059] Comparative Example 2 The difference between this and the radiation shielding cover and its preparation method in Example 2 is that all "bismuth oxide" is replaced with "barium sulfate".

[0060] Comparative Example 3 The difference between this and the radiation shielding cover and its preparation method in Example 3 is that all "bismuth oxide" is replaced with "barium sulfate".

[0061] Comparative Example 4 The difference between this and the radiation shielding cover and its preparation method in Example 4 is that all "bismuth oxide" is replaced with "barium sulfate".

[0062] Comparative Example 5 The difference between this and the radiation shielding cover and its preparation method in Example 5 is that all "bismuth oxide" is replaced with "barium sulfate".

[0063] Comparative Example 6 The difference between this and the radiation shielding cover and its preparation method in Example 6 is that all "bismuth oxide" is replaced with "barium sulfate".

[0064] Comparative Example 7 The difference between this and the radiation shielding cover and its preparation method in Example 10 is that all "bismuth oxide" is replaced with "barium sulfate".

[0065] The radiation shielding materials prepared in Examples 5-10 were subjected to heat resistance and cold resistance tests. The heat resistance test followed the method in QB / T 1857 5.5.2, the People's Republic of China Light Industry Standard for Snow Cream: The radiation shielding material was placed in an oven at 40±1℃ for 24 hours, then removed and allowed to stand until room temperature was reached. The changes in the protective agent's properties were observed, and no oil-water separation was required. The cold resistance test followed the method in QB / T 1857 5.6.2: The radiation shielding material was irradiated and placed in a refrigerator at -5~-15℃ for 24 hours, then removed and allowed to stand until room temperature was reached. The changes in the protective agent's properties were observed, and the oil seepage rate was required to be no greater than 3%. The test results for heat resistance and cold resistance are shown in Table 1.

[0066] Table 1. Test results of heat resistance and cold resistance

[0067] As can be seen from Table 1, when the mass content of bismuth oxide in the radiation shielding covering of the present invention is 45%~85%, there is no demulsification or stratification after high temperature and low temperature treatment, indicating good morphological stability.

[0068] The pH values ​​of the radiation shielding coverings prepared in Examples 5-10 (with bismuth oxide content of 45%, 55%, 65%, 70%, 80%, and 85% by mass) were determined according to the dilution method in GB / T 13531.1 General Test Methods for Cosmetics - Determination of pH Value: 1g of radiation shielding covering sample was weighed and added to 10g of boiled and cooled laboratory water. The mixture was heated to 40°C and stirred continuously until homogeneous. After cooling to 25°C, the precipitate was filtered and the pH value was measured using a pH meter. The required pH value range was 4.0-8.5.

[0069] The pH values ​​of the radiation shielding coverings prepared in Examples 5-10 of this invention were measured as follows: Figure 1 As shown. From Figure 1 As can be seen, the pH value of the radiation shielding cover in Example 5 (with a bismuth oxide content of 45%) was 8.19, the pH value of the radiation shielding cover in Example 6 (with a bismuth oxide content of 55%) was 8.36, the pH value of the radiation shielding cover in Example 7 (with a bismuth oxide content of 65%) was 8.39, the pH value of the radiation shielding cover in Example 8 (with a bismuth oxide content of 70%) was 8.31, the pH value of the radiation shielding cover in Example 9 (with a bismuth oxide content of 80%) was 8.55, and the pH value of the radiation shielding cover in Example 10 (with a bismuth oxide content of 85%) was 8.62. The pH values ​​of the radiation shielding covers in Examples 5 to 10 were all within or close to the acceptable range.

[0070] The safety of the radiation shielding covering prepared in Example 5 of this invention (containing 45% bismuth oxide by mass) was tested using a closed patch test on human skin. Twelve volunteers aged 18-60 years who met the test requirements were selected as subjects. The radiation shielding covering prepared in Example 5 was used as the test material, with an area of ​​approximately 50 mm². 2 A qualified spot tester with a depth of approximately 1 mm was used. The test substance was placed in the small chamber of the spot tester, and the dosage was controlled between 0.020 and 0.025 g. The spot tester containing the test substance was then applied to the flexor side of the subject's forearm with hypoallergenic adhesive tape. The palm was used to gently press the spot tester to ensure it was evenly applied to the skin for 24 hours. Skin reactions were observed at 30 min, 6 h, 12 h, 24 h, and 48 h after the spot tester was removed. The observations and records were based on the skin adverse reaction grading standard table shown in Table 2.

[0071] Table 2. Grading Standards for Adverse Skin Reactions

[0072] In the safety testing of the radiation shielding covering prepared in Example 5 of this invention, no volunteers experienced adverse reactions such as skin erythema, herpes, or confluent herpes, and all subjects passed the patch test. This indicates that the radiation shielding covering provided by this invention has high safety and is non-irritating to the skin.

[0073] Physical shielding experiments were conducted on the carrier cream prepared in Example 5 of the present invention (the mass content of barium sulfate and bismuth oxide in the carrier cream was 0%), as well as the radiation shielding covers prepared in Examples 1-6 of the present invention (the mass content of bismuth oxide in the radiation shielding cover was 5%, 15%, 25%, 35%, 45%, and 55%, respectively) and Comparative Examples 1-6 (the mass content of barium sulfate in the radiation shielding cover was 5%, 15%, 25%, 35%, 45%, and 55%, respectively). The radiation shielding cover or carrier cream was evenly applied to a petri dish with a diameter of 6 cm, with a coating thickness of 1 mm and 2 mm, respectively. The petri dish was then placed 10 cm away from the Sr.-90 radiation source, and a dosimeter was placed on the back of the petri dish to detect the radiation dose.

[0074] The appearance images of the carrier cream and radiation shielding cover prepared in Example 5 of this invention at different application thicknesses are shown below. Figure 2 As shown. From Figure 2 As can be seen, both the carrier cream and the radiation shielding cover with a bismuth oxide content of 45% exhibit good spreadability and can be evenly applied when the coating thickness is 1 mm and 2 mm, respectively.

[0075] A schematic diagram of the radiation shielding rate determination method in the physical shielding experiment of this invention is shown below. Figure 3 As shown. The petri dish is placed 10 cm away from the Sr.-90 radiation source. The thickness of the carrier cream or radiation shielding covering in the polyethylene plastic petri dish can be adjusted. A radiation dosimeter is placed on the back of the petri dish to detect the radiation dose.

[0076] The radiation shielding efficiency of the carrier cream prepared in Example 5 of this invention, and the radiation shielding coatings prepared in Examples 1-6 and Comparative Examples 1-6, against mixed radiation generated by a strontium-90 radioactive source under different coating thicknesses is as follows: Figure 4 As shown. From Figure 4It can be seen that when the concentration of barium sulfate in the radiation shielding covering is 0%, 5%, 15%, 25%, 35%, 45%, and 55%, the corresponding radiation shielding rates with a coating thickness of 1 mm are 52.63%, 50.67%, 55.30%, 54.12%, 55.34%, 56.41%, and 57.10%, respectively, and the corresponding radiation shielding rates with a coating thickness of 2 mm are 79.46%, 82.61%, 80.04%, 80.22%, 84.32%, 83.35%, and 84.0%, respectively. 4%; When the concentration of bismuth oxide in the radiation shielding covering is 0%, 5%, 15%, 25%, 35%, 45%, and 55%, the radiation shielding rates corresponding to a coating thickness of 1 mm are 52.63%, 60.24%, 58.59%, 64.40%, 64.01%, 67.99%, and 66.84%, respectively, and the radiation shielding rates corresponding to a coating thickness of 2 mm are 79.46%, 82.61%, 83.37%, 88.38%, 88.80%, 89.70%, and 90.58%, respectively. The radiation shielding efficiency of the bismuth oxide-containing radiation shielding cover is superior to that of the barium sulfate-containing radiation shielding cover under the same conditions. The radiation shielding efficiency of the radiation shielding cover against the mixed rays generated by the strontium-90 radioactive source increases with the increase of the mass content of bismuth oxide in the radiation shielding cover. Furthermore, the thicker the coating, the higher the radiation shielding efficiency of the radiation shielding cover against the mixed rays. When the coating thickness reaches 2 mm, the radiation shielding cover of Example 6 of the present invention has a radiation shielding efficiency as high as 90%, proving that the radiation shielding cover of the present invention can more effectively shield the mixed rays generated by the strontium-90 radioactive source.

[0077] The radiation shielding effect of the carrier cream prepared in Example 5 (with a bismuth oxide content of 0%), the radiation shielding cover prepared in Example 5 (with a bismuth oxide content of 45%), and the radiation shielding cover prepared in Comparative Example 5 (with a barium sulfate content of 45%) on X-rays at the cellular level was tested through in vitro experiments. Mouse skin melanoma (B16) cells and human immortalized epidermal (HaCaT) cells in the logarithmic growth phase were digested and made into single-cell suspensions. The cells were counted and seeded into each well of a cell culture plate at the same cell density for cell cloning experiments. The radiation shielding cover or carrier cream was filled into the corresponding positions of two wells on the outer surface of the cap. The unfilled wells were the blank group. During the culture, X-rays were irradiated into the corresponding wells from the outside. After the culture was completed, the samples were stained with crystal violet and the cloning status of each group of samples was detected.

[0078] The schematic diagrams of the cell cloning experiments performed on the blank group, the carrier cream prepared in Example 5 of this invention, and the radiation shielding coverings prepared in Example 5 and Comparative Example 5 are shown below. Figure 5As shown. Among them, the blank group had no filling in the holes, while the other three groups were filled with the carrier cream prepared in Example 5 (the mass content of bismuth oxide in the carrier cream was 0%), the radiation shielding cover prepared in Example 5 (the mass content of bismuth oxide in the radiation shielding cover was 45%), and the radiation shielding cover prepared in Comparative Example 5 (the mass content of barium sulfate in the radiation shielding cover) respectively.

[0079] The radiation shielding effects of the blank group, the carrier cream prepared in Example 5 of this invention, and the radiation shielding coverings prepared in Example 5 and Comparative Example 5 on X-rays (radiation dose of 4 Gy) on mouse skin melanoma (B16) cells are shown in the figure below. Figure 6 As shown. From Figure 6 It can be seen that when no X-ray irradiation is performed (i.e., radiation dose is 0 Gy), a large number of B16 cells can be observed. After X-ray irradiation (radiation dose is 4 Gy), the number of B16 cell clones formed in the blank group without filler is greatly reduced. The number of B16 cell clones formed in the group filled with the carrier cream prepared in Example 5 is also greatly reduced. The number of B16 cell clones formed in the group filled with the radiation shielding cover prepared in Comparative Example 5 is certain, but lower than that in the group filled with the radiation shielding cover prepared in Example 5.

[0080] Figure 6 The statistical results of clonogenicity of mouse skin melanoma (B16) cells are shown in the figure below. Figure 7 As shown (represented by the number of clones). From Figure 7 As can be seen, the number of clones in the unirradiated group, the blank group, the carrier cream group prepared in Example 5 of this invention, and the radiation shielding covering group prepared in Example 5 and Comparative Example 5 were 97.3, 14.2, 18, 76.7, and 45.5, respectively. For B16 cells, the number of clones formed in the carrier cream group prepared in Example 5 of this invention was not significantly different from that in the blank group, while the number of clones formed in the radiation shielding covering group prepared in Example 5 of this invention was significantly different from that in the blank group. This proves that the carrier cream itself has almost no ability to reduce the inhibitory effect of X-rays on cell clones, while the radiation shielding covering group prepared in this invention can effectively shield X-rays and reduce the inhibitory effect of X-rays on cell clones. At the same time, the number of clones formed in the radiation shielding covering group prepared in Example 5 of this invention is significantly better than that in the radiation shielding covering prepared in Comparative Example 5, indicating that bismuth oxide has a better shielding effect on X-rays than barium sulfate.

[0081] The radiation shielding effects of the blank group, the carrier cream prepared in Example 5 of this invention, and the radiation shielding coverings prepared in Example 5 and Comparative Example 5 on X-rays (radiation dose of 4 Gy) on human immortalized epidermal (HaCaT) cells are shown in the figure below. Figure 8 As shown. From Figure 8It can be seen that when no X-ray irradiation is performed (i.e., radiation dose is 0 Gy), a large number of HaCaT cells can be observed. After X-ray irradiation (radiation dose is 4 Gy), the number of HaCaT cell clones formed in the blank group without filler is significantly reduced. The number of HaCaT cell clones formed in the group filled with the carrier cream prepared in Example 5 is also significantly reduced, but slightly better than the blank group. The number of HaCaT cells formed in the group filled with the radiation shielding cover prepared in Comparative Example 5 is certain, but significantly lower than that in the group filled with the radiation shielding cover prepared in Example 5.

[0082] Figure 8 Statistical results of clonogenic formation of human immortalized epidermal (HaCaT) cells Figure 9 As shown (the left figure uses the number of clones, and the right figure uses the total area of ​​the clones). From Figure 9 It can be seen that the number of clones in the unirradiated group, the blank group, the carrier cream group prepared in Example 5 of this invention, and the radiation shielding covering group prepared in Example 5 and Comparative Example 5 were 684.7, 203.7, 213.3, 461.3, and 466, respectively, and the corresponding clone areas were 67704.7 pixels. 2 12223pixel 2 13084.7 pixels 2 56827 pixels 2 28993.7 pixels 2 For HaCaT cells, the colony formation numbers in the blank group, the carrier cream group prepared in Example 5 of this invention, and the radiation shielding cover group prepared in Example 5 showed a similar trend to those of B16 cells. However, when comparing the radiation shielding cover prepared in Example 5 of this invention with the radiation shielding cover group prepared in Comparative Example 5, although there was no significant difference in the number of colonies, it was clearly observed that the colony area of ​​the radiation shielding cover group prepared in Example 5 of this invention was much larger than that of the radiation shielding cover group prepared in Comparative Example 5. This demonstrates that bismuth oxide has a better shielding effect against X-rays than barium sulfate.

[0083] B16 cells and HaCaT cells derived from melanin were seeded into cell culture plates for cytotoxicity assays. The same cell density was used for seeding the same types of cells. The wells corresponding to the two types of cells were subjected to the same filling and irradiation treatments as described above, respectively, to obtain blank groups, carrier cream groups prepared in Example 5 of this invention (the carrier cream contained 0% bismuth oxide by mass), and radiation shielding covering groups prepared in Example 5 (the radiation shielding covering contained 45% bismuth oxide by mass). Cell viability was detected after 3 days and 5 days of irradiation, and LDH expression was detected after 3 days of irradiation.

[0084] After using the blank group, the carrier cream prepared in Example 5 of this invention, and the radiation shielding cover prepared in Example 5, X-rays (radiation dose of [missing information]) were applied to mouse skin melanoma (B16) cells. Cell viability assays after 3 days of X-ray irradiation, cell viability assays after 5 days of X-ray irradiation, and LDH expression assays after 3 days of X-ray irradiation are shown in the following figures. Figure 10 As shown. From Figure 10 It can be seen that after 3 days of irradiation, the cell viability of the unirradiated group, the blank group, the carrier cream group prepared in Example 5, and the radiation shielding covering group prepared in Example 5 were 100%, 62.17%, 69.95%, and 82.56%, respectively, and the LDH release rates were 23.84%, 30.25%, 29.34%, and 21.1%, respectively; after 5 days of irradiation, the cell viability of the unirradiated group, the blank group, the carrier cream group prepared in Example 5, and the radiation shielding covering group prepared in Example 5 were 100%, 58.15%, 70.78%, and 85.45%, respectively. Therefore, after X-ray irradiation (radiation dose of...), the cell viability of the unirradiated group, the blank group, the carrier cream group prepared in Example 5, and the radiation shielding covering group prepared in Example 5 were 100%, 58.15%, 70.78%, and 85.45%, respectively. The B16 cell viability in the control group on days 3 and 5 after X-ray irradiation was significantly lower than that in the control group. The B16 cell viability in the carrier cream group prepared in Example 5 was somewhat improved compared to the control group, but significantly lower than that in the radiation shielding cover group prepared in Example 5 after X-ray irradiation (radiation dose was...). The LDH release rate of B16 cells on day 3 after X-ray irradiation was significantly higher than that of cells without X-ray irradiation. The increase in LDH release rate of the carrier cream group prepared in Example 5 was slightly smaller than that of the blank group. The LDH release rate of the radiation shielding cover group prepared in Example 5 was comparable to that of cells without X-ray irradiation.

[0085] Cell viability assays of human immortalized epidermal (HaCaT) cells after X-ray (radiation dose of 10 Gy) irradiation for 3 days, 5 days, and 3 days after X-ray irradiation, and LDH expression assays, are shown in the following figures: blank group, carrier cream prepared in Example 5 of this invention, and radiation shielding cover prepared in Example 5. Figure 11 As shown. From Figure 11It can be seen that after 3 days of irradiation, the cell viability of the unirradiated group, the blank group, the carrier cream group prepared in Example 5, and the radiation shielding cover group prepared in Example 5 were 100%, 33.42%, 33.84%, and 53.81%, respectively, and the LDH release rates were 14.52%, 30.31%, 35.28%, and 28.79%, respectively; after 5 days of irradiation, the cell viability of the unirradiated group, the blank group, the carrier cream group prepared in Example 5, and the radiation shielding cover group prepared in Example 5 were 100%, 33.37%, 33.10%, and 50.64%, respectively. Therefore, the HaCaT cell viability in the blank group on days 3 and 5 after X-ray irradiation was significantly lower than that in the group without X-ray irradiation. The cell viability of the carrier cream group prepared in Example 5 was not significantly different from that of the blank group. The cell viability of the radiation shielding cover group prepared in Example 5 was significantly higher than that of the blank group and the carrier cream group. The LDH release rate of HaCaT cells in the blank group on day 3 after X-ray irradiation was significantly higher than that in the group without X-ray irradiation. The LDH release rate of the carrier cream group was slightly higher than that of the blank group. The LDH release rate of the radiation shielding cover group prepared in Example 5 was lower than that of the carrier cream group and the blank group.

[0086] comprehensive Figures 10-11 As a result, it can be seen that the radiation shielding covering prepared by the present invention can effectively isolate X-rays from damage to human immortalized epidermal cells.

[0087] The appearance of the radiation shielding coverings prepared in Examples 5-10 and Comparative Example 7 of this invention are shown in the following figures. Figure 12 As shown. From Figure 12 It can be seen that when the mass content of bismuth oxide in the radiation shielding cover is 45-85%, it has good dispersibility. When the mass content of bismuth oxide in the radiation shielding cover reaches 85%, the radiation shielding cover still exhibits ductility and can be spread. However, when the mass content of barium sulfate in the radiation shielding cover is 85%, it cannot be mixed evenly, and obvious agglomeration can be observed. When bismuth oxide is the radiation shielding component, the upper limit of the mass content of the radiation shielding component in the radiation shielding cover can be increased.

[0088] The carrier cream prepared in Example 5 of this invention (with a bismuth oxide content of 0%) and the radiation shielding coverings prepared in Examples 5-10 (with bismuth oxide contents of 45%, 55%, 65%, 70%, 80%, and 85%, respectively) were treated with human immortalized epidermal (HaCaT) cells using the same methods as the cell cloning and cytotoxicity experiments described above to verify their radiation shielding effects.

[0089] The radiation shielding effect of the blank group, the carrier cream prepared in Example 5 of this invention, and the radiation shielding coverings prepared in Examples 5-10 on X-ray irradiation (radiation dose of 4 Gy) on human immortalized epidermal (HaCaT) cells is shown in the figure below. Figure 13 As shown, the statistical results of clone formation are as follows: Figure 14 As shown. From Figure 14 As can be seen, the number of HaCaT cell clones formed in the unirradiated group, the blank group, the carrier cream group prepared in Example 5, and the carrier cream groups prepared in Examples 5-10 were 244, 40.33, 57.33, 117.5, 129, 163, 156, 205.5, and 218.5, respectively. Therefore, after X-ray irradiation, the number of HaCaT cell clones formed in the unirradiated group was significantly reduced compared to the unirradiated group. The number of clones formed in the carrier cream group was not significantly different from that in the blank group. The number of clones formed in the groups filled with radiation shielding coverings prepared in Examples 5-10 was significantly increased compared to the blank group and the carrier cream group. At the same time, the number of cell clones formed showed an increasing trend with the increase of bismuth oxide mass content.

[0090] Cell viability assays of human immortalized epidermal (HaCaT) cells after 3 days of X-ray (radiation dose of 10 Gy) irradiation using the blank group, the carrier cream prepared in Example 5 of this invention, and the radiation shielding coverings prepared in Examples 5-10 are shown in the figure. Figure 15 As shown. From Figure 15 As can be seen, the cell viability of the unirradiated group, the blank group, the carrier cream group prepared in Example 5, and the radiation shielding covering groups prepared in Examples 5-10 were 100%, 56.27%, 55.94%, 64.37%, 62.21%, 63.59%, 69.93%, 66.34%, and 68.57%, respectively. Therefore, as the mass content of bismuth oxide in the radiation shielding covering increases, the cell viability shows a slight upward trend.

[0091] comprehensive Figures 13-15 The results show that the higher the bismuth oxide content in the radiation shielding covering, the stronger the radiation shielding ability.

[0092] Male mice weighing 18g ± 2g were used for animal experiments. Mice were randomly divided into four groups based on weight: a blank group, a carrier cream group prepared in Example 5 (carrier cream containing 0% bismuth oxide), a radiation shielding covering group prepared in Example 5 (radiation shielding covering containing 45% bismuth oxide), and a radiation shielding covering group prepared in Example 10 (radiation shielding covering containing 85% bismuth oxide). Mice in the blank group had no application to their skin. Mice in the carrier cream group and the radiation shielding covering group had the same thickness (2mm) of carrier cream and radiation shielding covering applied to their skin, respectively. The legs of the mice were then irradiated with X-rays (radiation dose of...). Mice were irradiated on the back with a mixture of radiation from a strontium-90 source (irradiation dose was...). After irradiation, the skin damage on the legs and backs of mice in each group was observed.

[0093] The damage images of the blank group, the carrier cream prepared in Example 5 of this invention, and the radiation shielding coverings prepared in Examples 5 and 10, applied to the legs of mice and irradiated with X-rays for 18 and 28 days are shown below. Figure 16 As shown. From Figure 16 It can be seen that 18 days after irradiation, the blank group showed severe skin damage including ulcers and loss of full-thickness skin, while the damage in the carrier cream group prepared in Example 5 of this invention was less than that in the blank group. The mice in the radiation shielding cover group prepared in Example 5 of this invention only showed mild skin damage such as erythema and dry desquamation on their legs, while the mice in the radiation shielding cover group prepared in Example 10 of this invention showed almost no skin damage on their legs. Furthermore, as the time after irradiation was extended to 28 days, the damage in the blank group improved but was still relatively severe, while the carrier cream group prepared in Example 5 of this invention showed significant improvement. The radiation shielding cover group prepared in Example 5 and the radiation shielding cover group prepared in Example 10 of this invention showed almost no skin damage.

[0094] The blank control group, the carrier cream prepared in Example 5 of this invention, and the radiation shielding coverings prepared in Examples 5 and 10 were used on the legs of mice, and HE pathological sections were obtained after 40 days of X-ray irradiation. Figure 17 As shown. From Figure 17 It can be seen that the blank group had missing epithelium and hair follicles. The carrier cream group prepared in Example 5 of the present invention had severe hair follicle damage. The radiation shielding cover group prepared in Example 5 of the present invention and the radiation shielding cover group prepared in Example 10 of the present invention had less hair follicle damage, especially the radiation shielding cover group prepared in Example 10 of the present invention.

[0095] The blank group, the carrier cream prepared in Example 5 of this invention, and the radiation shielding coverings prepared in Examples 5 and 10 were used on the legs of mice. The skin damage scoring curves after X-ray irradiation of the legs are shown below. Figure 18 As shown. On days 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 34, and 38, the skin scores of the legs of mice in the control group were 2.07, 2.61, 3.64, 4.21, 4.61, 4.75, 4.71, 4.64, 4.18, 3.96, 3.79, 3.64, 3.43, 3.04, and 2.89, respectively. The skin scores of mice in the group treated with the carrier cream prepared in Example 5 of this invention were 1, 1.17, 1.5, 2.17, 3, 3.83, 3.83, and 3. The scores for the skin on the legs of mice treated with the radiation shielding covering prepared in Example 5 of this invention were 1, 1, 1, 1, 1.5, 2.25, 2.25, 2.5, 2.25, 2, 1.5, 1.5, 1.25, 1, 1, respectively. The scores for the skin on the legs of mice treated with the radiation shielding covering prepared in Example 10 of this invention were 1, 1, 1, 1.17, 1.17, 1.17, 1.33, 1.17, 1, 1, 1, 1, 1, 1, 1, 1, respectively. As can be seen, the blank group suffered the most severe damage and recovered the slowest. Significant damage (approximately 3.5 points) began to appear on day 10 post-irradiation, with the damage score rapidly increasing and peaking between days 12 and 22 (4.18–4.75 points). Although the score subsequently decreased, overall recovery was slow, remaining at a relatively high damage level of 2.89 points at the end of the experiment (day 38). The damage score of the carrier cream group prepared in Example 5 showed a similar trend over time to the blank group, but the degree of damage was slightly lower. This group peaked between days 16 and 20 (3.67–3.83 points), then gradually recovered, decreasing between days 28 and 38. The radiation shielding cover group prepared in Example 5 showed a significantly lower damage score compared to the blank group and the carrier cream group throughout the entire process, with a faster recovery rate. Slight redness appeared on day 14 (1.5 points), peaking at only 2.5 points on day 20, and then began to decline, reaching 1 point after day 34, returning to normal skin condition. The radiation shielding cover group prepared in Example 10 maintained the lowest damage level (1-1.33 points) throughout the observation period, with no obvious damage peak. Compared to the other three groups, this group showed the mildest skin reaction, with almost no typical radiation dermatitis symptoms. These results indicate that although the carrier cream has a certain moisturizing or shielding effect, it cannot effectively resist radiation damage. Medium concentrations of bismuth oxide can effectively slow down acute radiation damage to the skin, while high concentrations of bismuth oxide have the most significant radiation shielding and protective effects.

[0096] The damage images of mice after irradiation with strontium-90 mixed rays at 19, 21, 36, and 47 days following application of the blank group, the carrier cream prepared in Example 5 of this invention, and the radiation shielding coverings prepared in Examples 5 and 10 to the backs of mice are shown below. Figure 19 As shown. From Figure 19 It can be seen that 19 days after irradiation with Sr. 90 mixed rays, the mice in the blank group showed severe open skin damage on their backs, while the mice in the carrier cream group prepared in Example 5 of this invention showed obvious dryness and crusting on their backs. No skin damage was observed in the radiation shielding covering group prepared in Example 5 and the radiation shielding covering group prepared in Example 10. Furthermore, the mice in the blank group died 21 days after irradiation, and the mice in the carrier cream group prepared in Example 5 of this invention died 36 days after irradiation. No deaths were observed in the radiation shielding covering group prepared in Example 5 and the radiation shielding covering group prepared in Example 10 throughout the entire irradiation process. However, comparing the hair growth of the mice in the radiation shielding covering group prepared in Example 5 and the radiation shielding covering group prepared in Example 10 47 days after irradiation, it can be seen that the hair growth in the radiation shielding covering group prepared in Example 5 was slower than that in the radiation shielding covering group prepared in Example 10, demonstrating that the radiation shielding effect of the radiation shielding covering increases with the increase of the bismuth oxide content in the carrier cream.

[0097] As can be seen from the above embodiments, the radiation shielding covering provided by the present invention has good morphological stability, and there is no demulsification or stratification after high temperature and low temperature treatment; the pH value is 8.2~8.6, which is highly safe and non-irritating to the skin; and the radiation shielding effect is good against mixed rays and X-rays generated by Strontium-90 radioactive sources.

[0098] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A radiation shielding covering, comprising a carrier cream and bismuth oxide, wherein the bismuth oxide content in the radiation shielding covering is 5%~85% by mass; the carrier cream comprises ethylparaben, xanthan gum, cetearyl alcohol, white petrolatum, sodium lauryl sulfate, phenoxyethanol, and deionized water; wherein the mass ratio of ethylparaben, xanthan gum, cetearyl alcohol, white petrolatum, sodium lauryl sulfate, and phenoxyethanol is 1:(0.4~0.6):(7.5~8.5):(7.5~8.5):(0.9~1.1):(0.9~1.1); and the deionized water content in the carrier cream is 80.5%~93.5% by mass.

2. The radiation shielding covering according to claim 1, characterized in that, The bismuth oxide content in the radiation shielding covering is 45% to 85% by mass.

3. The radiation shielding covering according to claim 2, characterized in that, The bismuth oxide content in the radiation shielding covering is 65% to 85% by mass.

4. A method for preparing the radiation shielding covering according to any one of claims 1 to 3, comprising the following steps: Ethylparaben, xanthan gum, and deionized water were first mixed to obtain an aqueous phase. Cetearyl alcohol, white petrolatum, and sodium lauryl sulfate were mixed in a second step to obtain the oil phase. The aqueous phase and the oil phase are mixed in a third process, and then mixed with phenoxyethanol in a fourth process to obtain a carrier cream. The carrier cream and bismuth oxide are mixed in a fifth step to obtain a radiation shielding coating.

5. The method for preparing the radiation shielding covering according to claim 4, characterized in that, The first mixing step involves adding ethylparaben to deionized water, followed by the addition of xanthan gum.

6. The method for preparing the radiation shielding covering according to claim 4 or 5, characterized in that, The temperatures of the first mixture, the second mixture, and the third mixture are independently 80~90°C; the temperature of the fourth mixture is 40~60°C.

7. The method for preparing the radiation shielding covering according to claim 4, characterized in that, After the fourth mixture is prepared, deionized water is added for dilution to obtain a carrier cream.

8. The method for preparing the radiation shielding covering according to claim 7, characterized in that, The temperature of the deionized water is 95~100℃.

9. The method for preparing the radiation shielding covering according to claim 4, characterized in that, The first, second, third, fourth, and fifth mixtures are carried out under stirring conditions; the stirring speed of the first mixture is 180~220 rpm / min; the stirring speed of the second, third, and fourth mixtures is independently 500~800 rpm / min; and the stirring speed of the fifth mixture is 2500~3500 rpm / min.

10. The use of the radiation shielding covering according to any one of claims 1 to 3 or the radiation shielding covering prepared according to the preparation method according to any one of claims 4 to 9 in shielding X-rays and strontium-90 rays.

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