Title:
RADIOACTIVE MICROSPHERE THAT IS EXCELLENT IN CHEMICAL DURABILITY AND METHOD FOR MANUFACTURING IT
Document Type and Number:
Japanese Patent JP3490015
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To obtain radioactive microspheres that are excellent in chemical durability and can directly emit radiation for a long term through the implantation of them near a tumor in a patent's body by composing them of crystals of an oxide containing radioactive yttrium of a specific wt.%.
SOLUTION: As to the composition of radioactive microspheres, crystals of an oxide containing radioactive yttrium of 47 wt.% or more account for 99% or more of them and unavoidable compounds make up the rest. The content of yttrium in yttria is 78 wt.% or more when crystals of an oxide are Y2O3, whereby an affected part can be irradiated with 2.47 times as much radiation dose as that in the use of glass. YPO4 and a mixture of Y2O3 and YPO4 are also acceptable as crystals of an oxide. When they are YPO4, the lower limit of the content of yttrium in the microspheres as a whole drops to 48 wt.% but the effect of increasing radioactivity by phosphorus with a long half-life period is made. In addition, it is acceptable that the microspheres are covered with a coating of silica, titania, alumina and the like, which enhances the resistance to acids and enables the long-term irradiation with radiation.
Inventors:
Tadashi Kokubo
Masakazu Kawashita
Masahiro Hiraoka
Yasushi Nagata
Yoshiaki Inoue
Mountain Zaki Takao
Yasuhiro Shimizu
Yoshiki Sawada
Masakazu Kawashita
Masahiro Hiraoka
Yasushi Nagata
Yoshiaki Inoue
Mountain Zaki Takao
Yasuhiro Shimizu
Yoshiki Sawada
Application Number:
JP6475899A
Publication Date:
January 26, 2004
Filing Date:
March 11, 1999
Export Citation:
Assignee:
Kansai TLO Co., Ltd.
Neturen Co., Ltd.
Shimizu Tech Co., Ltd.
Neturen Co., Ltd.
Shimizu Tech Co., Ltd.
International Classes:
A61K9/00; A61K9/51; A61K51/00; A61K51/12; C01B13/14; C01F17/00; G21G1/06; G21G4/06; G21G4/08; (IPC1-7): G21G4/08; A61K9/00; A61K9/51; A61K51/00; C01B13/14; C01F17/00; G21G1/06
Other References:
【文献】標葉亮 ら,癌放射線治療用微小球の合成,日本セラミックス協会第13回秋季シンポジウム講演予稿集,日本,2000年10月11日,pp. 281,JST No. L2240A
Attorney, Agent or Firm:
Masayuki Yano
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