radioactive isotopes 223 Ra / 89 Zr-labeled nano-hydroxyapatite and its preparation method and application

Abstract

The invention belongs to the technical field of material preparation, and specifically relates to a radioactive isotope 223 Ra / 89 Zr-labeled nano-hydroxyapatite and its preparation method and application. The present invention adopts direct precipitation method to synthesize dual-nuclide labeled nano-hydroxyapatite, which has high safety and high stability of the nuclides labeled thereon.

Description

Technical Field

[0001] The invention belongs to the technical field of material preparation, and specifically relates to a radioactive isotope 223 Ra / 89 Zr-labeled nano-hydroxyapatite and its preparation method and application. Background Art

[0002] Although the incidence of malignant bone tumors is relatively low among all types of cancer, due to the large population of my country, the number of patients can reach a scale that cannot be ignored. After bone tumor surgery, radiotherapy or chemotherapy is required to further eliminate cancer cells. Currently, radionuclide internal irradiation therapy is mostly used. Radionuclide internal irradiation therapy is to introduce radionuclides into the patient's body by intravenous injection, oral administration or interstitial placement, and then use the rays emitted by the radionuclides to irradiate tumor cells, thereby killing tumor cells and ultimately shrinking or eliminating the lesions. Compared with external radiotherapy, radionuclide internal irradiation therapy can more accurately provide large doses of radiation to the target area without causing inappropriate radiation and damage to normal tissues.

[0003] The alpha particles produced by the decay of alpha nuclides have a strong relative biological effect. Their efficiency in killing tumor cells is significantly better than that of beta rays, but their damage to surrounding normal tissues is lower than that of beta rays. Therefore, they have few side effects and are highly safe. The alpha nuclides that are widely studied in the field of nuclear medicine include 223 Ra, 225 Ac, 227 Th, 211 At etc. Radium chloride ( 223 RaCl2) injection is the only FDA-approved radionuclide drug that emits alpha particles, and its safety has been widely confirmed in clinical practice. 223 Ra's treatment of tumors is mainly through intravenous injection. When the drug is injected into the human body, 223 Ra can naturally target the osteoblastic region of the bone matrix to act on tumors. However, multiple studies have confirmed 223 Ra will be taken up by the digestive system, thereby reducing its radionuclide content in the lesion and easily causing damage to normal cells.

[0004] Nano-hydroxyapatite (nHA), as the main inorganic component of bone matrix, has good biocompatibility, good application value in clinical and drug carrier research, and has been widely used in the clinical treatment of bone defects. Since Ra and Ca are of the same family and have similar physical and chemical properties, α-emitting radionuclides or radionuclides that serve as in vivo generation elements of α-emitting radionuclides have been introduced into hydroxyapatite. The patent with publication number CN1972720A (May 30, 2007) and invention name "α-emitting hydroxyapatite microparticles" discloses the introduction of α-emitting radionuclides or radionuclides that serve as in vivo generation elements of α-emitting radionuclides into hydroxyapatite, wherein the α-emitting radionuclides are selected from 211 At, 212 Bi, 223 Ra, 224 Ra, 225 Ac or 227 Th. The patent also discloses a method for preparing radionuclide-labeled hydroxyapatite. One of the problems solved by the patent is that hydroxyapatite particles can be labeled with alpha-emitting radionuclides and stably retain radionuclides for a certain period of time. However, the patent method uses adsorption to label the nuclides, which will cause the radionuclides on the surface of nHA to be continuously delabeled over time, so the stability is insufficient.

[0005] In summary, it is necessary to propose new methods and strategies to alleviate or partially alleviate the shortcomings of existing technologies. Summary of the invention

[0006] In view of this, the object of the present invention is to provide a radioactive medical isotope 223 Ra / 89 Zr-labeled nano-hydroxyapatite and its preparation method, the specific technical scheme is as follows.

[0007] A method for preparing dual-nuclide labeled nano-hydroxyapatite, wherein the dual nuclides are 223 Ra and 89 Zr, the method uses a direct precipitation method for synthesis, and the specific steps are as follows:

[0008] S01: Ca(NO3)2·4H2O is placed in a first reaction container, (NH4)2HPO4 is placed in a second reaction container, the volume of the second reaction container is smaller than the volume of the first reaction container, and then the second reaction container is placed in the first reaction container;

[0009] S02: Mix PEG solution with 223 The mixed solution of RaCl2 solution is added dropwise into the second reaction container until it is full;

[0010] S03: Mix the PEG solution with 223 The mixed solution of RaCl2 solution is added dropwise to the first reaction container until the liquid levels of the first reaction container and the second reaction container are the same, the entire reaction system is allowed to stand, and the PEG solution and the mixed solution of RaCl2 solution are further added dropwise to the first reaction container. 223 RaCl2 solution, until the liquid level in the first reaction container is 5 mm higher than the liquid level in the second reaction container, thereby generating a liquid level difference;

[0011] S04: At the position of the liquid level difference, calcium ions react fully with PEG to form a PEG-Ca-PEG linker, and the PEG-Ca-PEG linker further reacts with (NH4)2HPO4 to generate nano-hydroxyapatite, and then the first reaction container is sealed and placed at room temperature to allow the nano-hydroxyapatite to be fully incubated to obtain the labeled 223 Nano-hydroxyapatite of Ra;

[0012] S05: The product after incubation in the first reaction container is centrifuged and washed with deionized water, and then the product is freeze-dried (the experimental team found in the previous experiment that the marker produced by incubation in the first reaction container 223 Ra nanohydroxyapatite is incubated in the second reaction vessel to produce a labeled 223 The nano-hydroxyapatite of Ra has different particle sizes and masses, and the product after incubation in the first reaction container is preferably used);

[0013] S06: 89 ZrCl4 solution was added to the freeze-dried product, shaken, and free nuclides were removed by centrifugation and washing with distilled water to obtain dual-nuclide labeled nano-hydroxyapatite.

[0014] Furthermore, the calcium-phosphorus ratio of the Ca(NO3)2·4H2O and the (NH4)2HPO4 is 0.6.

[0015] Furthermore, the percentage concentration of the PEG solution is 5-10%, and the pH value ranges from 10-12.

[0016] Furthermore, the PEG solution is a PEG6000 aqueous solution, and the pH value is adjusted by adding ammonia water.

[0017] Further, the 223 The radioactivity of the RaCl2 solution is 0.3-0.5MBq; 89 The radioactivity of ZrCl4 solution is 120-150MBq.

[0018] Further, the 223RaCl2 solution and 89 The dosage ratio of ZrCl4 solution is 1:1.

[0019] Furthermore, the centrifugal operation conditions in S05 and S06 are 1000-2000 rpm, centrifugation 3-10 min; the shaking operation conditions in S06 are 30° C.-37° C., 100-500 rpm, 0.5-1 h.

[0020] Furthermore, the freeze-drying conditions in S05 are set as follows: temperature range is -50°C to -90°C; pressure range is 0.01-0.1MPa, and freezing time is 48-72h.

[0021] The dual-nuclide labeled nano hydroxyapatite prepared by the above method.

[0022] Furthermore, the particle size of the nano-hydroxyapatite is in the range of 200-300 nm.

[0023] The application of the dual-nuclide labeled nano hydroxyapatite prepared by the above method in the preparation of drugs for treating malignant bone tumors.

[0024] Beneficial technical effects

[0025] (1) This patent provides a method for preparing a dual-nuclide labeled nano-hydroxyapatite ( 223 Ra / 89 Zr@nHA) is a kind of dual-nuclide labeled nHA, which is very stable and almost never loses its label. 223 Ra is slowly released and exerts its therapeutic effect, providing long-lasting radiotherapy efficacy on target cells in the human body; 89 Zr can be used as a tracer marker to trace this nanomaterial in vivo. 223 Ra / 89 Zr@nHA is highly secure and can be intervened promptly if there are any problems.

[0026] (2) The present invention prepares this 223 Ra / 89 Zr@nHA is suitable for the preparation of drugs for the treatment of malignant bone tumors. Bone tumors are often accompanied by a decrease in bone biomechanical strength. Bone filling with biomaterials can enhance the biomechanical properties of bone. Nanohydroxyapatite, as the main inorganic component of bone matrix, has good biocompatibility. Based on the similar physical and chemical properties of Ra and Ca, nanomaterials have good biocompatibility. 223Ra can partially replace Ca ions in hydroxyapatite and serve as the basis for the formation of nano-hydroxyapatite. 223 Ra / 89 Zr@nHA has the combined effect of intratumoral radiotherapy and bone repair, and can realize real-time tracking in vivo. 223 Compared with RaCl2, the 223 Ra / 89 Zr@nHA has better effect.

[0027] (3) The preparation method of the present invention uses a low amount of reagents and has a low cost, and is suitable for large-scale industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, each element or part is not necessarily drawn according to the actual scale. Obviously, the drawings described below are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings without paying creative labor.

[0029] Figure 1 It is a schematic diagram of the reaction system structure of the present invention;

[0030] Figure 2 The verification diagram of the dual-nuclide labeled nano-hydroxyapatite prepared by the present invention (A is an electron microscope diagram, with a scale of 100 nm; B is a diagram of particle size measurement results; C is an X-ray diffraction diagram; and D is a Fourier transform infrared spectrum diagram);

[0031] Figure 3 The stability study results (A is the stability study of nHA labeled with nuclides obtained by different preparation methods, wherein C represents the "homogeneous" in-situ substitution (doping) method, and S represents the adsorption method; B is the stability study of nHA labeled with nuclides prepared by the "homogeneous" in-situ substitution (doping) method using PEG and not using PEG; C is the pH stability study of nHA labeled with nuclides prepared by the method of the present invention);

[0032] Figure 4 is the cytotoxicity and apoptosis detection results (A is the dual-nuclides labeled nHA and 223 A is a cytotoxicity test diagram of RaCl2 solution; B is a flow cytometry test diagram of dual-nuclide labeled nHA prepared by the method of the present invention; C is 223 Flow cytometry experiment of RaCl2 solution). DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in combination with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] Herein "and / or" includes any and all combinations of one or more of the associated listed items.

[0035] Herein, "plurality" means two or more than two, ie, it includes two, three, four, five, etc.

[0036] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0037] As used in this specification, the term "about" typically means + / - 5% of the stated value, more typically + / - 4% of the stated value, more typically + / - 3% of the stated value, more typically + / - 2% of the stated value, even more typically + / - 1% of the stated value, and even more typically + / - 0.5% of the stated value.

[0038] In this specification, some embodiments may be disclosed in a format of being within a certain range. It should be understood that such description of "being within a certain range" is only for convenience and brevity, and should not be interpreted as a rigid limitation on the disclosed range. Therefore, the description of the range should be considered to have specifically disclosed all possible sub-ranges and independent numerical values ​​within this range. For example, the range The description of should be considered to have specifically disclosed sub-ranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6 etc., as well as individual numbers within this range, for example, 1, 2, 3, 4, 5, and 6. The above rules apply regardless of the breadth of the range.

[0039] Example 1

[0040] This embodiment provides an example of a method for preparing dual-nuclide labeled nano-hydroxyapatite.

[0041] S01: Place Ca(NO3)2·4H2O at the bottom of a 100ml first reaction container, place (NH4)2HPO4 at the bottom of a 25ml second reaction container, and then place the second reaction container into the first reaction container.

[0042] S02: Mix PEG solution with 223 The mixed solution of RaCl2 solution is added dropwise into the second reaction container until it is full. The PEG solution is a PEG6000 aqueous solution with a mass percentage concentration of 6.00% (the pH of the PEG solution is adjusted to 11 by adding ammonia water).

[0043] S03: Mix the PEG solution in S02 with 223 The mixed solution of RaCl2 solution was added dropwise to the first reaction container until the liquid levels of the first reaction container and the second reaction container were the same, and the whole system was allowed to stand for 5 minutes, and the PEG solution and the mixed solution of RaCl2 solution were further added dropwise to the first reaction container. 223 The mixed solution of RaCl2 solution is added until the liquid level in the first reaction container is 5 mm higher than the liquid level in the second reaction container. At the 5 mm liquid level difference, the calcium ions react fully with PEG to form a PEG-Ca-PEG linker, and the PEG-Ca-PEG linker continues to react with (NH4)2HPO4 to generate nano-hydroxyapatite.

[0044] S04: Seal the first reaction container and place it at room temperature for 4 days to allow the compounds in the reaction system to fully incubate and obtain the labeled 223 Ra nanohydroxyapatite ( 223 Ra@nHA).

[0045] S05: centrifuging the product after incubation in the first reaction container, washing it with deionized water, and then freeze-drying the product. The parameters of the centrifugal operation are 1500 rpm and 5 minutes. The parameters of freeze-drying are: adjusting the temperature range to -50°C to -90°C, the pressure range to 0.01-0.1 MPa, and the freezing time to 48-72 hours.

[0046] S06: 89 The ZrCl4 solution was added to the freeze-dried product, shaken, and free nuclides were removed by centrifugation and washing with distilled water to obtain double nucleic acid labeled nano-hydroxyapatite. The parameters of the centrifugal operation were 1500 rpm, centrifugation for 5 minutes, and the parameters of the shaking operation were 37°C, 200 rpm, and shaking for 1 hour.

[0047] In the above preparation method, the calcium-phosphorus ratio of Ca(NO3)2·4H2O and (NH4)2HPO4 is 0.6.

[0048] In the above preparation method, 223 The radioactivity of the RaCl2 solution is 0.37MBq; 89 The radioactivity of ZrCl4 solution is 150MBq, and the dosage is 1ml.

[0049] Example 2

[0050] This embodiment provides a dual-nuclide labeled nano-hydroxyapatite prepared by the method of Example 1.

[0051] The dual-nuclide labeled nano-hydroxyapatite prepared by the method of Example 1 is referred to as 223 Ra / 89 Zr nanohydroxyapatite ( 223 Ra / 89 Zr@nHA). Among them, radionuclides 223 Ra was introduced into the interior of the nano-hydroxyapatite molecule by the method of "homogeneous" in-situ substitution (doping), and then 89 Zr was used for in vivo tracing. Figure 2 , Figure 2 It was proved that PEG was successfully synthesized 223 Ra / 89 Zr nanohydroxyapatite.

[0052] Example 3

[0053] This example provides a verification of the effect of dual-nuclide labeled nano-hydroxyapatite.

[0054] 3.1 Comparative test of different synthesis methods

[0055] Provided is a preparation method for labeling nuclides using adsorption means.

[0056] The specific operation is the same as that in Example 1, except that no 223 RaCl2. The labeling and purification steps are as follows:

[0057] The reaction product and 223 After mixing with RaCl2, the mixture was incubated in a dry thermostatic metal bath (30 min, 200 rpm, 40°C), centrifuged three times (5 min, 1500 rpm), and free nuclides were removed by centrifugation and washing with distilled water.

[0058] 3.2 Stability test investigation

[0059] The marker prepared in Example 1 2233.1 Preparation and labeling of Ra nanohydroxyapatite (“homogeneous” in-situ substitution (doping) method) 223 Ra nanohydroxyapatite (adsorption method), take 3μL (1.11MBq) of the product to be tested and add it to 27μL of phosphate buffered saline (PBS) and newborn bovine serum (FBS), mix them thoroughly and evenly and store them at room temperature. At different time points (depending on the half-life of different nuclides), take the above radioactive mixture with a glass capillary and develop it. Remove the free radionuclides by centrifugation and washing with distilled water. The stability of the obtained product is defined by this formula (1):

[0060]

[0061] Where LR is the labeling rate of the radionuclide. C0 is the cpm value of the input radionuclide, measured by the γ-counter. C1 is the cpm value of the supernatant and the distilled water after washing measured by the γ-counter.

[0062] The results are as follows Figure 3 Compared with the control experiment which uses adsorption to label the nuclides, the difference of the method of the present invention is that the strategy of "homogeneous" in-situ substitution (doping) of radionuclides is used. 223 The synthesis of Ra@nHA has significantly improved 223 Stability of Ra

[0063] 3.3 Control experiment without PEG template in chemical synthesis

[0064] Method: The sources of calcium and phosphorus were calcium nitrate and disodium hydrogen phosphate, respectively. Ammonium hydroxide was used to adjust the pH to 9. 0.25 M calcium nitrate solution was added to 0.15 M disodium hydrogen phosphate solution and stirred until the Ca / P molar value was 1.67. Then 0.015 M sodium tripolyphosphate (STPP) and 223 RaCl2. The temperature was adjusted to 40-60°C to form the nHA precursor. The precipitate was transferred to a stirred hydrothermal reactor at 160°C for 8 h. The cooled nHA precipitate was washed with deionized water and then ethanol and filtered to remove free radionuclides. Finally, the precipitate was dried in a 50°C laboratory oven for 24 h.

[0065] 3.4 Stability investigation

[0066] The marker prepared in Example 1 223 3.3 Preparation and labeling of Ra nanohydroxyapatite (“homogeneous” in situ substitution (doping) method) with PEG 223 The stability test of Ra nanohydroxyapatite ("homogeneous" in-situ substitution (doping) method without PEG) was carried out according to 3.2.

[0067] The results are as follows Figure 3 Compared with the control experiment using no PEG template, the difference of the method of the present invention is that the strategy of "homogeneous" in-situ substitution (doping) of radionuclides based on the PEG template is used. 223 The synthesis of Ra@nHA has significantly improved 223 Stability of Ra.

[0068] In addition, the marker prepared in Example 1 of the present invention 223 Ra nanohydroxyapatite also has good pH stability, such as Figure 3 As shown in C, it can maintain stability in the environment of pH 7.4 to pH 10.

[0069] Example 4

[0070] Cytotoxicity and apoptosis detection of the dual-nuclide labeled nano hydroxyapatite prepared by the invention.

[0071] 4.1 Cytotoxicity

[0072] Method steps: (1) Prepare a concentration of 2.5×10 4 / mL human osteosarcoma cells (MG-63 cells) and human embryonic lung fibroblasts (MRC-5 cells) resuspension. Take three 96-well plates for each group, block the outermost circle of wells with 200μL PBS, add 100μL of the above cell resuspension to each of the 6×10 wells in the middle, and let it stand for 24h. After the standing time is over, remove the supernatant from the cells in the wells and add 190μL of the corresponding cell culture medium. (2) 223 Ra / 89 Zr@nHA was diluted to 7.4KBq / μL ( 223 Ra dose was determined), 10 gradients were diluted with 2-fold concentration gradient, and added to the cells of 96-well plate, 10 μL per well, and three controls per gradient. 223 Ra / 89 After Zr@nHA, the 96-well plate was placed in a constant temperature cell incubator and taken out after 96 hours. The supernatant was aspirated and then washed three times with 200 μL PBS. (3) 223 A control group was set up with RaCl2 solution. (4) Take the MTS cytotoxicity detection kit and prepare the MTS solution, specifically: 20% MTS + 80% cell culture medium. Add 100 μL of the above-prepared MTS solution to each well of the 96-well plate, mix well and place in the incubator. Observe the color change every half an hour, and use a spectrophotometer to detect when the color is appropriate (wavelength 490nm). Calculate the data and fit the image using Origin software.

[0073] 4.2 Cell apoptosis detection

[0074] Method steps: (1) Prepare a concentration of 2.5×10 4 12-well plates were taken, 2 mL of the above cell suspension was added to each well, and the cells were cultured in a cell incubator. (2) After the cells were completely attached to the wall the next day, 0 KBq, 18.5 KBq, 37 KBq, and 74 KBq of each well were added to each well. 223 Ra / 89 Zr@nHA( 223 (3) After 96 hours, take out the 12-well plate, transfer the supernatant to a 1.5 mL centrifuge tube, centrifuge at 4000 rpm for 5 minutes, and discard the supernatant. Add 1 mL of PBS to wash, transfer the washed PBS to the same 1.5 mL centrifuge tube, centrifuge at 4000 rpm for 5 minutes, discard the supernatant, and repeat three times to completely collect the cells in the supernatant. (4) Next, add 100 μL of trypsin to each well of the 12-well plate for digestion. After the digestion time is up, add 1 mL of the corresponding culture medium to terminate the digestion. After mixing by blowing, transfer to a 1.5 mL centrifuge tube, centrifuge at 4000 rpm for 5 minutes, discard the supernatant, add 1 mL of PBS to wash, transfer the washed PBS to the same 1.5 mL centrifuge tube, centrifuge at 4000 rpm for 5 minutes, discard the supernatant, and repeat three times to completely collect the adherent cells. (5) Use the same dose of 223 A control group was set up with RaCl2 solution. (6) Finally, the Annexin V-FITC apoptosis detection kit was taken, 500 μL of 1×BindingBuffer solution was added to the centrifuge tube, and the cells were resuspended. Under light-proof conditions, 5 μL of Annexin V-FITC staining solution and 5 μL of propidium iodide (PI) staining solution were added to the tubes respectively, and the mixture was mixed by pipetting and incubated at room temperature in the dark for 20 minutes. After the incubation, the flow cytometer was used for detection immediately (if the detection cannot be performed immediately, it should be placed on ice in the dark and the detection should be completed within 1 hour). The data were calculated and the image was fitted using Origin software.

[0075] The results are as follows Figure 4 shown. Figure 4 As shown in A, 223 Ra / 89 Zr@nHA showed dose-dependent cytotoxicity to both cell lines, and the toxicity was greater than 223 RaCl2. Secondly, compared with human embryonic lung cells MRC-5, 223 Ra / 89Zr@nHA has a specific dose-dependent cytotoxicity to human osteosarcoma cells MG-63. After treatment with the highest dose (37KBq) for 72h, MG-63 cells 223 Ra / 89 The survival rate after Zr@nHA treatment was about 32.72%, which was much lower than that after 223 65.22% after RaCl2 treatment. 223 Ra / 89 Zr@nHA can effectively kill target cells.

[0076] Flow cytometry was used to analyze 223 Ra / 89 Zr@nHA and 223 Is the killing effect of RaCl2 on MG-63 cells related to its triggering of programmed cell death? Figure 4 As shown in B and C. Through the analysis of apoptotic cell populations (AnnexinV-fitc / PI), it was found that at high doses, 223 Ra / 89 Zr@nHA has the strongest ability to induce cell apoptosis, and both drugs induce cell apoptosis in a dose-dependent manner. 223 Ra / 89 The total apoptosis rate of MG-63 cells treated with Zr@nHA was about 30.86%, of which early apoptosis (Annexin V+ / PI-) was about 7.85% and late apoptosis (AnnexinV+ / PI+) was about 23.01%. 223 After the same treatment time of RaCl2, the total apoptosis rate of MG-63 cells was about 19.41%, of which the early apoptosis (Annexin V+ / PI-) was about 3.27% and the late apoptosis (Annexin V+ / PI+) was about 15.75%. 223 Ra / 89 Under the action of Zr@nHA, cell apoptosis was more obvious. Finally, by analyzing the cell necrosis (Annexin V- / PI+), it can be seen that both drugs induced cell necrosis in MG-63 cells, but the proportion was small and there was no dose-dependent and specific induction of cell necrosis. This indicates that 223 Ra / 89 Zr@nHA and 223 The cell death pathway caused by RaCl2 is mainly through activating programmed cell death and inducing cell apoptosis.

[0077] in conclusion: 223 Ra / 89Zr@nHA has a dose-dependent and specific cytotoxic effect on bone tumor cells MG-63, and its cell killing effect is better than that of 223 RaCl2 solution.

[0078] In general, doping with PEG as a template improves 223 The specific activity of Ra@nHA is better than that of the same dose of 223 Ra is higher and stronger. It can kill tumors at the same time. 89 Zr labeling can achieve the purpose of real-time tracking of radioactive drugs in vivo.

[0079] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation modes, which are merely illustrative rather than restrictive. Under the guidance of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the present invention and the claims, all of which are within the protection of the present invention.

Claims

1. A method for preparing dual-nuclide labeled nano-hydroxyapatite, characterized in that: The binuclear nuclides are 223 Ra and 89 Zr, the method uses a direct precipitation method for synthesis, and the specific steps are as follows: S01: Ca(NO3)2·4H2O is placed in a first reaction container, (NH4)2HPO4 is placed in a second reaction container, the volume of the second reaction container is smaller than the volume of the first reaction container, and then the second reaction container is placed in the first reaction container; S02: Mix PEG solution with 223 The mixed solution of RaCl2 solution is added dropwise to the second reaction container until it is full. 223 The radioactivity of the RaCl2 solution is 0.3-0.5 MBq; the PEG solution is a PEG6000 aqueous solution with a percentage concentration of 5-10% and a pH range of 10-12; S03: mixing the PEG solution with 223 The mixed solution of RaCl2 solution is added dropwise to the first reaction container until the liquid levels of the first reaction container and the second reaction container are the same, the entire reaction system is allowed to stand, and the PEG solution and the mixed solution of RaCl2 solution are further added dropwise to the first reaction container. 223 RaCl2 solution, until the liquid level in the first reaction container is higher than the liquid level in the second reaction container, resulting in a liquid level difference; S04: At the position of the liquid level difference, calcium ions react fully with PEG to form a PEG-Ca-PEG linker, and the PEG-Ca-PEG linker further reacts with (NH4)2HPO4 to generate nano-hydroxyapatite, and then the first reaction container is sealed and placed at room temperature to allow the nano-hydroxyapatite to be fully incubated to obtain the labeled 223 Nano-hydroxyapatite of Ra; S05: centrifuging the product after incubation in the first reaction container, washing it with deionized water, and then freeze-drying the product; S06: 89 ZrCl4 solution is added to the freeze-dried product. 89 The radioactivity of the ZrCl4 solution is 120-150 MBq. 223 RaCl2 solution and 89 The ZrCl4 solution was used in a ratio of 1:1, shaken, and free nuclides were removed by centrifugation and washing with distilled water to obtain dual-nuclide labeled nano-hydroxyapatite.

2. The method according to claim 1, characterized in that The calcium-phosphorus ratio of the Ca(NO3)2·4H2O and the (NH4)2HPO4 is 0.

6.

3. The method according to claim 1, characterized in that The pH of the PEG solution was adjusted by adding aqueous ammonia.

4. The method according to claim 1, wherein: The centrifugal operation conditions in S05 and S06 are 1000-2000 rpm, centrifugation for 3-10 min; the shaking operation conditions in S06 are 30° C.-37° C., 100-500 rpm, 0.5-1 h.

5. The method according to claim 1, wherein The freeze drying conditions in S05 are set as follows: temperature range is -50°C to -90°C; pressure range is 0.01-0.1MPa, and freezing time is 48-72h.

6. The dual-nuclide labeled nano-hydroxyapatite prepared by the method according to any one of claims 1 to 5, characterized in that: The particle size of the nano-hydroxyapatite is in the range of 200-300 nm.

7. Use of the dual-nuclide labeled nano-hydroxyapatite prepared by the method according to any one of claims 1 to 5 in the preparation of drugs for treating malignant bone tumors.

Images