A silica-supported ceria core-shell material, a preparation method thereof and application thereof in Ge / Ga separation

Abstract

The application relates to the technical field of isotope separation, in particular to a SiO2@CeO2 core-shell material with silica supported cerium dioxide, a preparation method thereof and application of the SiO2@CeO2 core-shell material in Ge / Ga separation. 68 Efficient adsorption of Ge and 68 Effective elution of Ga; the SiO2@CeO2 core-shell material is used as a stationary phase, hydrochloric acid is used as a mobile phase, Ge / Ga is efficiently separated based on solid-phase extraction, and therefore the SiO2@CeO2 core-shell material can be used as 68 Ge- 68 Ga generator column packing.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of isotope separation, and particularly relates to a silica-supported ceria core-shell material, a preparation method thereof and application of the material in Ge / Ga separation. BACKGROUND

[0002] In recent years, 68 Ga has become a widely used medical isotope in positron emission tomography (PET) due to its superior nuclear properties, such as high positron emission rate (89%, maximum energy 1899 keV, average energy 890 keV), suitable half-life (68 min), and easy-to-label chemical properties. A variety of 68 Ga-labeled radiopharmaceuticals (such as 68 Ga-DOTA-TATE, 68 Ga-DOTA-TOC, 68 Ga-PSMA-11, 68 Ga-FAPI-04) have shown important value in the early clinical imaging of various cancers. In addition, 68 Ga-labeled diagnostic drugs can be used in combination with 177 Lu or 225 Ac-labeled therapeutic drugs (such as 68 Ga-DOTATATE with 177 Lu-DOTATATE, 68 Ga-PSMA-617 with 225 Ac-PSMA-617), achieving diagnosis and treatment integration, and thus simultaneously completing diagnosis and treatment in cancer management.

[0003] With the expansion of nuclear medicine applications, the global demand for 68 Ga has rapidly grown. Currently 68 Ga is mainly produced by a cyclotron via the 68 Zn(p,n) 68 Ga reaction, or obtained from a 68 Ge- 68 Ga generator. The column packing of the generator has a key impact on its performance. The reported adsorption materials include inorganic oxides such as Al2O3, SnO2, TiO2, ZrO2, CeO2, Ta2O5, organic resins, nano-oxides, and inorganic-organic composite materials. Commercial generator materials mainly include SnO2 of iThemba LABS, pyrogallol-modified SiO2 of ITG, and TiO2 of EZAG.

[0004] SiO2 has a porous structure, which is beneficial to active site exposure, and is chemically stable under strong acid and radiation environments, has no metal ion elution, and can avoid interference with 68Ga labeling. Its high specific surface area (500-1000 m² / g) and tunable pore size (2-50 nm) help to optimize 68 Ge / 68 Ga adsorption and desorption kinetics, while high mechanical strength ensures column bed stability. However, SiO2 itself is not selective for 68 Ge / 68 Ga. SUMMARY

[0005] The purpose of the present application is to provide a silica-supported ceria core-shell material and its preparation method and application in Ge / Ga separation, which modifies CeO2 on the surface of mesoporous SiO2 to form a SiO2@CeO2 core-shell structure. The SiO2 core provides a rigid skeleton and radiation stability, and the CeO2 shell realizes 68 efficient adsorption of Ge and 68 effective desorption of Ga.

[0006] To achieve the above purpose, the technical scheme adopted by the present application is as follows:

[0007] A preparation method of a silica-supported ceria core-shell material, comprising the following steps:

[0008] Step 1: preparing mesoporous SiO2;

[0009] Dissolve 5-10 parts by mass of PEG-10000 in 50-100 parts by volume of 1 mol / L acetic acid solution, then add 20-50 parts by volume of tetramethyl orthosilicate TMOS, and stir for 15-45 min to form a sol;

[0010] In a sealed environment, gelate the sol at a temperature of 30-50°C for 36-48 h to obtain a wet gel; solvent exchange the wet gel with ammonia water for 6-12 h, dry, and calcine at a temperature of 500-800°C for 3-6 h to obtain mesoporous SiO2;

[0011] Step 2: preparing a SiO2@CeO2 core-shell material;

[0012] Dissolve the mesoporous SiO2 prepared in step 1 in deionized water to form a mesoporous SiO2 dispersed aqueous solution; dissolve cerium nitrate hexahydrate in deionized water to form a cerium nitrate hexahydrate aqueous solution;

[0013] Under stirring, add the mesoporous SiO2 dispersed aqueous solution to the cerium nitrate hexahydrate aqueous solution, and then add ammonia water, and precipitate at a temperature of 80-100°C by co-precipitation; centrifuge, wash, and dry to obtain a SiO2@CeO2 core-shell material, wherein the mass ratio of SiO2 to CeO2 is 1:1-1.5.

[0014] The application is prepared by using PEG-10000, tetramethyl orthosilicate, acetic acid, cerium nitrate hexahydrate, ammonia and other raw materials, and is a core-shell material with excellent performance of SiO2 and CeO2. 68 Efficient adsorption of Ge and 68 Effective elution of Ga.

[0015] The application also provides a method for separating Ge / Ga, using the SiO2@CeO2 core-shell material as a stationary phase and inorganic acid as a mobile phase, based on solid phase extraction method. 68 Ge / 68 Ga, and further proves that the SiO2@CeO2 core-shell material has 68 Ge- 68 Ga generator column packing. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 The scanning electron microscope image of the prepared SiO2 for the embodiment 1 of the application.

[0017] Figure 2 The scanning electron microscope image of the prepared SiO2@CeO2 core-shell material for the embodiment 1 of the application.

[0018] Figure 3 The elution effect diagram of the SiO2@CeO2 core-shell material of the application.

[0019] Figure 4 The elution effect diagram of the SiO2 of the application. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the application will be clearly and completely described below with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments of the application.

[0021] Embodiment 1:

[0022] The embodiment provides a SiO2@CeO2 core-shell material, and a preparation method thereof includes the following steps.

[0023] Step 1: 8.86g of PEG-10000 is dissolved in 75mL of acetic acid solution with a concentration of 1mol / L, and 50mL of tetramethyl orthosilicate TMOS (Si(OCH3)4) is added, and high-speed stirring is performed for 30min to form a sol;

[0024] The sol is transferred into a polyethylene tube, sealed, and the sol is gelled in an environment with a temperature of 30-50℃ for 48h to form a wet gel, and the wet gel is solvent exchanged with 0.05mol / L ammonia water (the concentration of the ammonia water affects the pore size of the SiO2) for 10h; dried at a temperature of 30-50℃; then heated to 600℃ at a heating rate of 8℃ / min and calcined for 5h to obtain mesoporous SiO2, and a scanning electron microscope image of the mesoporous SiO2 is shown in Figure 1 .

[0025] Step 2: 1.0g of mesoporous SiO2 is added to 50mL of deionized water to form a mesoporous SiO2 aqueous dispersion; 8g of cerium nitrate hexahydrate is dissolved in 50mL of deionized water to form a cerium nitrate hexahydrate aqueous solution,

[0026] The mesoporous SiO2 aqueous dispersion is added to the cerium nitrate hexahydrate aqueous solution under high-speed stirring, and 100-200mL of an ammonia water solution with a concentration of 0.01-0.5mol / L is added, and a SiO2@CeO2 core-shell material is obtained by a co-precipitation method under high-speed stirring at a temperature of 80-100℃ for 5-10h, centrifugation, washing, drying at 80-100℃ for 12-24h, grinding, and sieving, and a scanning electron microscope image of the SiO2@CeO2 is shown in Figure 2 , and the mass ratio of SiO2 to CeO2 is 1:1-1.5.

[0027] Example 2

[0028] This example provides a method for separating Ge / Ga based on solid phase extraction.

[0029] (1) The SiO2 prepared in step 1 and the SiO2@CeO2 core-shell material prepared in step 2 of Example 1 are separately loaded into a SPE column with a hydrophilic sieve plate using a dry method, and a layer of glass fiber is laid on top, and 0.01-0.10mol / L hydrochloric acid is used to elute the fine powder in the column.

[0030] (2) A 1000ppm Ge / Ga standard solution is used to prepare a Ge / Ga stock solution with a pH of 1 and a concentration of 50ppm.

[0031] (3) 0.5mL of the 50ppm stock solution is loaded into the SPE column with SiO2 and the SiO2@CeO2 core-shell material, respectively, and then 4.5mL of 0.1mol / L hydrochloric acid is used for elution, with a flow rate of 1mL / min, and the eluate is collected, and the content of Ge and Ga ions in the eluate is determined by inductively coupled plasma emission spectrometry to obtain the elution curves of Ge and Ga, as shown in Figure 3 and Figure 4As shown, the prepared SiO2 and SiO2@CeO2 have good elution effect on Ga, and 90%-95% of Ga can be recovered in 1-1.5 mL eluent. In addition, the prepared SiO2@CeO2 can selectively adsorb Ge, and the separation of Ge and Ga has not been achieved, while SiO2 has no selectivity for Ge. It can be known that the SiO2@CeO2 core-shell material can be used as a material for separating Ge and Ga, thereby serving as a new type of 68 Ge- 68 Ga generator column packing.

[0032] The above merely provides the preferred embodiments of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can make equivalent replacements or changes according to the technical scheme and the inventive concept of the present application within the technical range disclosed by the present application, which should be covered within the protection scope of the present application.

Claims

1. A method for preparing a silica-supported ceria core-shell material, characterized in that, The method comprises the following steps: Step 1: preparing mesoporous SiO2; 5-10 parts by mass of PEG-10000 is dissolved in 50-100 parts by volume of acetic acid solution with a concentration of 1 mol / L, and then 20-50 parts by volume of tetramethyl orthosilicate TMOS is added, and stirring is performed for 15-45 min to form a sol; In a sealed environment, the sol is subjected to gelation at a temperature of 30-50 ℃ for 36-48 h to obtain a wet gel; the wet gel is subjected to solvent exchange with ammonia water for 6-12 h, dried, and calcined at a temperature of 500-800 ℃ for 3-6 h to obtain mesoporous SiO2; Step 2: preparing SiO2@CeO2 core-shell material; The mesoporous SiO2 prepared in step 1 is dissolved in deionized water to form a mesoporous SiO2 dispersed aqueous solution; cerium nitrate hexahydrate is dissolved in deionized water to form a cerium nitrate hexahydrate aqueous solution; Under stirring, the mesoporous SiO2 dispersed aqueous solution is added to the cerium nitrate hexahydrate aqueous solution, and then ammonia water is added, and the precipitation is performed by a co-precipitation method at a temperature of 80-100 ℃. Centrifugation, washing, and drying are performed to obtain the SiO2@CeO2 core-shell material, wherein the mass ratio of SiO2 to CeO2 is 1:1-1.

5.

2. The method for preparing a silica-supported cerium dioxide core-shell material according to claim 1, characterized in that, The temperature of the calcination is increased to 500-800 ℃ at a rate of 5-10 ℃ / min.

3. The method for preparing a silica-supported cerium dioxide core-shell material according to claim 1, characterized in that, The concentration of the ammonia water is 0.01-0.5 mol / L.

4. A SiO2@CeO2 core-shell material prepared by the method according to claim 1, 2, or 3.

5. A method for separating Ge / Ga using the SiO2@CeO2core-shell material of claim 4, characterized in that, With SiO2@CeO2core-shell material as stationary phase, with inorganic acid as mobile phase, based on solid phase extraction method separation 68 Ge / 68 Ga.

6. The method of separating Ge / Ga of the Si02@Ce02core-shell material according to claim 5, characterized in that, 5-15 parts by mass of SiO2@CeO2core-shell material is added to a SPE column with hydrophilic sieve plate, and a layer of glass fiber is laid on it; elution is carried out with 0.01-0.10 mol / L inorganic acid; and the solution containing 68 Ge / 68 Ga is columned, and elution is continued with 0.01-0.10 mol / L inorganic acid.

7. The method of separating Ge / Ga of the Si02@Ce02core-shell material according to claim 6, characterized in that, The inorganic acid is hydrochloric acid.

8. A method of claim 1 wherein the Ge- generator is a Ge- generator having a column packing of SiO2@CeO2 core-shell material as described in claim 3. 68 Ge- 68 Ga generator, the column packing of the Ge- generator is a SiO2@CeO2 core-shell material as described in claim 3. 68 Ge- 68 Ga generator, the column packing of the Ge- generator is a SiO2@CeO2 core-shell material as described in claim 3.

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