Method of preparing iodine-125 sealing seed source core

Abstract

The invention discloses a method for preparing an iodine-125 brachytherapy source core for treating tumor, which comprises the following steps: firstly, putting a standby filamentary silver in a 20-80 percent sodium hypochlorite solution, and performing oscillatory reaction at room temperature for one hour so that the surface of the filamentary silver is covered with a layer of compact AgCl deposition; and secondly, putting the filamentary silver into a mixture solution of an acetic acid buffer solution and a Na<125>I solution to react for one hour so that a layer of even and compact Ag<125>I deposition which is firm and hard to fall off is formed on the surface of the filamentary silver. The reagents used in the method are all conventional ones which are convenient to purchase and have low prices; irritant chlorine is not generated in the process of preparation; the surface of the iodine-125 brachytherapy source core is even and compact; the utilization rate of the radioiodine is high; and the process time is short, thus mass production is easy to realize.

Description

Technical field: [0001] The invention belongs to the technical field of radioactive implantation therapy, and is mainly used for the preparation method of the iodine-125 sealed seed source source core used for implanting brachytherapy in various tumors such as prostate cancer and brain tumors. Background technique: [0002] Interstitial implantation therapy is to implant radioactive seeds into tumor tissue, and use the rays emitted by the seed source to kill tumor cells and achieve the purpose of treating tumors. Years of clinical application have proved that the iodine-125 sealed seed source implanted in close range The treatment not only has a good curative effect on prostate cancer, but also has a good curative effect on different types of tumors in other parts. It has been reported abroad that seed source implantation therapy is significantly superior to other treatments in the treatment of head and neck, abdominal cavity, and pelvic cavity tumors, recurrence after radio...

AI Technical Summary

Problems solved by technology

[0005] The preparation method that U.S. Patent No. 4323055 and Chinese Patent Publication No. 1307907 disclose is to use silver as the carrier of immobilizing iodine-125, with halide salt (hypochlorite and chlorite) as oxidant oxidation and chlorine under 6M hydrochloric acid condition Chlorination reaction, silver rod after chlorination and radioactive iodine-125 solution carry out ion exchange reaction under the condition of pH10-12 for 18-22 hours, thus make the source core of iodine-125 seed source, the main deficiency of this method is reaction time Long, and a large amount of chlorine gas with pungent odor is produced in the reaction process, which will cause adverse effects on personnel and the environment, and it is not easy to carry out large-scale production

In Chinese Patent Publication No. 1265924A, hydrogen peroxide and hydrochloric acid are used for chlorination, followed by iodination for 18 hours. This method also has the disadvantages of long reaction time, too severe chlorination reaction, excessive chlorine gas production, and rough surface properties.

The method disclosed in Chinese Patent Publication No. 1593666A adopts potassium ferricyanide as oxidant chlorination for 3-8 hours, and iodides for 8-10 hours under alkaline conditions. Unfavorable, so it needs to be improved

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