Low density radionuclide-containing particulate material

Abstract

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.sup.3, processes for its production and a method of radiation therapy utilising the patentable material.

1 . 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.sup.3.  
   
   
       2 . The particulate material according to  claim 1 , wherein the density of the glass is less than 2.4 g/cm.sup.3, preferably less than 2.3 g/cm.sup.3 and more preferably less than 2.2 g/cm.sup.3.  
   
   
       3 . The particulate material according to  claim 1 , wherein the low density glass comprises from 95% to 100% SiO.sub.2.  
   
   
       4 . The particulate material according to  claim 1 , wherein the low density glass comprises SiO.sub.2 and B.sub.2O.sub.3, and the weight percentage of [SiO.sub.2+B.sub.2O.sub.3] in the glass is at least 70%.  
   
   
       5 . The particulate material according to  claim 4 , wherein the weight percentage of [SiO.sub.2+B.sub.2O.sub.3] in the glass is at least 80%, preferably at least 85% and more preferably at least 90%.  
   
   
       6 . The particulate material according to  claim 4 , wherein the SiO.sub.2 content of the glass is at least 60% by weight, and the B.sub.2O.sub.3 content is at least 10% by weight.  
   
   
       7 . The particulate material according to  claim 4 , wherein the composition of the glass is 72% SiO.sub.2, 25% B.sub.2O.sub.3, 1% Al.sub.2O.sub.3, 0.5% Li.sub.2O, 0.5% Na.sub.2O and 1% K.sub.2O.  
   
   
       8 . The particulate material according to  claim 1 , which is a microsphere having a diameter in the range of from 5 to 200 microns.  
   
   
       9 . The particulate material according to  claim 8 , wherein the diameter is in the range of from 15 to 100 microns, preferably from 20 to 50 microns, and more preferably from 30 to 35 microns.  
   
   
       10 . The particulate material according to  claim 1 , wherein the radionuclide is yttrium-90.  
   
   
       11 . The particulate material according to  claim 1 , wherein the radionuclide is an isotope of holmium, samarium, iodine, iridium, phosphorus or rhenium.  
   
   
       12 . 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.  
   
   
       13 . A process for the production of a particulate material according to  claim 1  comprising the steps of forming a low density radiation-tolerant glass core and coating the core with a radionuclide or radionuclide precursor, and then if necessary activating the precursor to form the radionuclide.  
   
   
       14 . The process according to  claim 12  or  claim 13 , wherein the radionuclide is yttrium-90.  
   
   
       15 . A method of radiation therapy of a patient, which comprises administration to the patient of a particulate material according to  claim 1 .  
   
   
       16 . The method according to  claim 15 , wherein the radionuclide is yttrium-90.  
   
   
       17 . The method according to  claim 15 , wherein the radiation therapy comprises treatment of a primary or secondary liver cancer.  
   
   
       18 . Use of particulate material according to  claim 1  in radiation therapy of a patient.  
   
   
       19 . Use according to  claim 18 , wherein the radionuclide is yttrium-90.  
   
   
       20 . Use according to  claim 16 , wherein the radiation therapy comprises treatment of a primary or secondary liver cancer.