Low density radionuclide-containing particulate material
The invention relates to a particulate material consisting of a low density radiation-tolerant glass and a radionuclide incorporated into the low density glass or coated on the low density glass, the glass having a density of less than 2.5 g/cm 3 , processes for its production and a method of radiation therapy utilising the patentable material.
1. A particulate material comprising a low density radiation-tolerant glass and one or two radionuclides incorporated into the low density glass, the glass having a density of less than 2.5 g/cm 3 , wherein the radionuclide is an isotope selected from the group consisting of holmium, samarium, iodine, iridium, rhenium, and yttrium, and wherein the low density glass comprises SiO 2 and B 2 O 3 , and the weight percentage of [SiO 2 +B 2 O 3 ] in the glass is at least 70%.
2. The particulate material according to claim 1 , wherein the density of the glass is less than 2.4 g/cm 3 .
3. The particulate material according to claim 1 , wherein low density glass comprises from 95% to 100% SiO 2 .
4. The particulate material according to claim 1 , wherein the weight percentage of [SiO 2 +B 2 O 3 ] in the glass is at least 80%.
5. The particulate material according to claim 1 , wherein the SiO 2 content of the glass is at least 60% by weight, and the B 2 O 3 content is at least 10% by weight.
6. The particulate material according to claim 1 , wherein the composition of the glass is 72% SiO 2 , 25% B 2 O 3 , 1% Al 2 O 3 , 0.5% Li 2 O 0.5% Na 2 O and 1% K 2 O.
7. The particulate material according to claim 1 , which is a microsphere having a diameter in the range of from 5 to 200 microns.
8. The particulate material according to claim 7 , wherein the diameter is in the range of from 15 to 100 microns.
9. The particulate material according to claim 1 , wherein the radionuclide is yttrium-90.
10. A process for the production of a particulate material according to claim 1 comprising melting together a low density radiation-tolerant glass and a radionuclide or radionuclide precursor and solidifying the melt to produce a particulate material, and then if necessary activating the precursor to form the radionuclide.
11. The process according to claim 10 , wherein the radionuclide is yttrium-90.
12. A method of radiation therapy of a patient, which comprises administration to the patient of a particulate material according to claim 1 .
13. The method according to claim 12 , wherein the radionuclide is yttrium-90.
14. The method according to claim 12 , wherein the radiation therapy comprises treatment of a primary or secondary liver cancer.
15. The particulate material according to claim 1 , wherein the density of the glass is less than 2.3 g/cm 3 .
16. The particulate material according to claim 1 , wherein the density of the glass is less than 2.2 g/cm 3 .
17. The particulate material according to claim 1 , wherein the weight percentage of [SiO 2 +B2O 3 ] in the glass is at least 85%.
18. The particulate material according to claim 1 , wherein the weight percentage of [SiO 2 +B2O 3 ] in the glass is at least 90%.
19. The particulate material according to claim 7 , wherein the diameter is in the range of from 20 to 50 microns.
20. The particulate material according to claim 7 , wherein the diameter is in the range of from 30 to 35 microns.