Search

CN-122005877-A - Preparation method and application of palladium-103 brachytherapy source core

CN122005877ACN 122005877 ACN122005877 ACN 122005877ACN-122005877-A

Abstract

The invention belongs to the technical field of radiopharmaceuticals and medical appliances, and discloses a preparation method and application of a palladium-103 brachytherapy source core, wherein the source core is composed of graphite particles which are subjected to surface modification treatment and adsorbed with radionuclide palladium-103. The preparation method comprises the steps of preparing graphite particles, conducting acidizing treatment and/or activating treatment on the graphite particles to introduce oxygen-containing functional groups on the surfaces of the particles and/or form a porous structure to obtain surface modified graphite particles, mixing the particles with alkaline solution containing palladium-103, and completing marking through vibration adsorption. According to the invention, the graphite particles are modified to replace a complex electroplating process, so that the high-efficiency and uniform adsorption of palladium-103 is realized, and the requirement on the purity of the graphite raw material is low. The method has the advantages of simple process, low cost and easy mass production, and the prepared source core has small self-shielding effect and is suitable for preparing the brachytherapy devices such as sealed seed sources, post-loading sources and the like.

Inventors

  • WANG CHENGJIE
  • DING MU
  • WANG QINGYANG
  • XIA CHUANQIN
  • ZHONG JUN

Assignees

  • 四川辐清药华生物医药科技有限公司

Dates

Publication Date
20260512
Application Date
20260203

Claims (8)

  1. 1. A palladium-103 brachytherapy source core comprising surface-modified graphite particles, and a radionuclide palladium-103 supported on the surface of the surface-modified graphite particles; Wherein the surface modified graphite particles are obtained through acidizing treatment and/or activating treatment, and the content of graphite is more than 60%.
  2. 2. A palladium-103 brachytherapy source core according to claim 1, wherein said surface modified graphite particles have a diameter of 0.1-1.0mm and a length of 0.5-5.0mm.
  3. 3. A method of making the palladium-103 brachytherapy source core of claim 1 or 2, comprising the steps of: step 1, preparing graphite particles; step 2, carrying out acidizing treatment and/or activating treatment on the graphite particles to obtain surface modified graphite particles; And 3, mixing the surface modified graphite particles with alkaline solution containing palladium-103 according to the mass volume ratio of 10-100mL/g, oscillating for 1-6 hours at 10-40 ℃ for adsorption reaction, washing and drying to obtain the source core.
  4. 4. A method according to claim 3, wherein in step 1, the graphite particles are prepared by mixing graphite, a binder and water, extruding, molding and drying; The adhesive adopts one or more of polyvinyl alcohol, carboxymethyl cellulose, acrylic resin, clay and polyvinyl acetate.
  5. 5. The method according to claim 3, wherein in the step 2, the acidification treatment is carried out by mixing graphite particles with concentrated nitric acid according to a mass volume ratio of 10-100mL/g, oxidizing for 2-24 hours at 60-150 ℃, washing and drying; the concentration range of the concentrated nitric acid is 1-14.5 mol/L; the activation treatment comprises mixing graphite particles with an activating agent according to a mass ratio of 1:2-10:1, and heating for 1-4 hours at 450-900 ℃ under the protection of inert gas; The activator is selected from one of chloride, nitrate or sulfate.
  6. 6. A method according to claim 3, wherein in step 3, the radioactive concentration of palladium-103 in the alkaline solution containing palladium-103 is 50-5000mCi/mL.
  7. 7. The method according to claim 6, wherein the alkali in the alkaline solution is selected from one or more of sodium hydroxide, potassium hydroxide, ammonium chloride, sodium carbonate, sodium bicarbonate, and ammonia water.
  8. 8. A radiation therapy device comprising the palladium-103 brachytherapy source core of claim 1 or 2 enclosed within a biocompatible housing; wherein the device is a sealed seed source, a post-load therapeutic source or a radioactive applicator.

Description

Preparation method and application of palladium-103 brachytherapy source core Technical Field The invention belongs to the technical field of radiopharmaceuticals and medical instruments, and particularly relates to a preparation method and application of a palladium-103 brachytherapy source core. Background The palladium [ Pd-103] brachytherapy source is a radioactive drug for tumor brachytherapy, is mainly used for permanent implantation treatment at low dosage rate, and is especially suitable for rapidly-proliferating tumor types such as prostate cancer, head and neck tumor, eye tumor and the like. The therapeutic source is typically composed of a biocompatible titanium shell and a radioactive source core sealed inside, wherein the source core is the core component that performs the radiation therapy function. At present, the preparation of palladium [ Pd-103] brachytherapy source core mainly adopts the following two methods: The preparation method is to immerse silver wires in alkaline solution containing palladium salt, and add reducing agents such as sodium thiosulfate, hydrazine and the like to enable palladium ions to be deposited on the surface of the silver wires in a reduction way, so that a compact palladium metal layer is formed. This method, while relatively simple to operate, has a significant self-shielding effect. Because of the low energy of the X-rays and gamma rays released by Pd-103 decay (about 20-23 keV), and the high atomic number and density of silver, significant absorption and scattering of high energy photons can occur as they pass through the silver carrier, resulting in a reduced effective exit dose, thereby affecting the therapeutic effect. Secondly, a source core based on a carbon material carrier is mainly prepared by adopting high-purity graphite particles through an electroplating process at present. The method is to take high-purity graphite particles as a cathode, put the cathode into electrolyte containing palladium chloride [ Pd-103] and ammonium chloride and the like, and electroplate palladium metal on the surfaces of the graphite particles through a conventional direct current electroplating technology. The electroplating technology can obtain a source core with higher apparent activity (0.5-300 mCi), but has the industrialization bottleneck that firstly, the electroplating process is complex, the equipment requirement is high, the operation of radioactive electrolyte is involved, radioactive pollution is easy to generate, the safety risk is high, secondly, the electroplating process requires that a graphite carrier has good conductivity, so that the purity requirement on graphite raw materials is extremely high, the raw material cost is high, and furthermore, hundreds to thousands of graphite particles with tiny diameters (0.1-1.0 mm) are required to be used as cathodes for uniform electroplating to meet clinical requirements, the process operation difficulty is extremely high, the batch consistency and the product uniformity are difficult to ensure, and finally, the palladium metal layer formed by electroplating is also relatively compact, and also has a certain self-shielding problem. In summary, the existing palladium [ Pd-103] source core preparation technology has the defects of strong self-shielding effect, complex process, high cost or difficult mass stable production and the like no matter the existing palladium [ Pd-103] source core preparation technology is a metal carrier or electroplated graphite. Therefore, development of a novel source core preparation method is urgently needed, the self-shielding effect can be reduced on the premise of guaranteeing efficient and uniform adsorption of radionuclides, the process flow is simplified, the harsh requirements on carrier materials are reduced, and the requirements of industrialized mass production are met. Disclosure of Invention The invention aims to provide a preparation method and application of a palladium-103 near-distance treatment source core, which improves the adsorption performance of graphite particles through chemical modification, replaces a complex electroplating process, and realizes high-efficiency and uniform loading of palladium-103, thereby obtaining the treatment source core with excellent performance, easy industrialization and lower cost. In order to achieve the above purpose, the invention adopts the following technical scheme: In a first aspect, the present invention provides a palladium-103 brachytherapy source core comprising surface-modified graphite particles, and a radionuclide palladium-103 supported on the surface of the surface-modified graphite particles; Wherein the surface modified graphite particles are obtained through acidizing treatment and/or activating treatment, and the content of graphite is more than 60%. The acidification treatment causes the surfaces of graphite particles to form a large number of oxygen-containing functional groups (-COOH, -OH) and the surface e