Polymer based radionuclide containing particulate material

Abstract

The invention relates to a particulate material having a diameter in the range of from 5 to 200 microns comprising polymeric matrix and stably incorporated radionuclide, processes for its production and a method of radiation therapy utilising the particulate material.

1 . A particulate material having a diameter in the range of from 5 to 200 microns comprising a polymeric matrix and stably incorporated radionuclide. 
     
     
         2 . The particulate material according to  claim 1  wherein the radionuclide is incorporated by precipitation. 
     
     
         3 . The particulate material according to  claim 1  wherein the polymeric matrix is partially cross linked. 
     
     
         4 . The particulate material according to  claim 3  wherein the polymeric matrix comprises from about 1% to about 20% cross linking. 
     
     
         5 . The particulate material according to  claim 4  wherein the polymeric matrix comprises about 4% cross linking. 
     
     
         6 . The particulate material according to  claim 1  wherein the polymeric matrix is an ion exchange resin. 
     
     
         7 . The particulate material according to  claim 6  wherein the polymeric matrix is a cation exchange resin. 
     
     
         8 . The particulate material according to  claim 6  wherein the ion exchange resin comprises a partially cross linked aliphatic polymer. 
     
     
         9 . The particulate material according to  claim 6  wherein the ion exchange resin comprises a partially cross linked polystyrene. 
     
     
         10 . The particulate material according to  claim 9  wherein the ion exchange resin comprises polystyrene partially cross linked with divinyl benzene. 
     
     
         11 . The particulate material according to  claim 1 , wherein the radionuclide is an isotope of yttrium, holmium, samarium, iodine, phosphorus, iridium or rhenium. 
     
     
         12 . The particulate material according to  claim 1 , wherein the radionuclide is yttrium-90. 
     
     
         13 . The particulate material according to  claim 1  being a microsphere. 
     
     
         14 . A particulate material according to  claim 1 , having a diameter in the range of from 30 to 35 microns comprising a copolymer comprised of styrene and divinyl benzene and precipitated yttrium-90. 
     
     
         15 . A process for the production of a particulate material according to  claim 1  comprising the step of combining a polymeric matrix and a radionuclide in solution for a time and under conditions sufficient to stably incorporate the radionuclide in the matrix to produce a particulate material having a diameter in the range of from 5 to 200 microns. 
     
     
         16 . A process according to  claim 15  wherein the radionuclide is stably incorporated by precipitation into the polymeric matrix. 
     
     
         17 . A process according to  claim 15  wherein the radionuclide is yttrium-90. 
     
     
         18 . A method of radiation therapy of a patient, which comprises administration to the patient of a particulate material having a diameter in the range of from 5 to 200 microns comprising a polymeric matrix and a stably incorporated radionuclide. 
     
     
         19 . A method according to  claim 18  wherein the radionuclide is yttrium-90. 
     
     
         20 . A method according to  claim 18  wherein the radiation therapy comprises treatment of a primary or secondary liver cancer. 
     
     
         21 .- 23 . (canceled) 
     
     
         24 . A process for the production of radioactive particulate material comprising a polymeric matrix and a radionuclide, comprising the steps of:
 Adsorbing a solubilized radionuclide into an ion exchange resin particulate material having particle with a diameter in the range of 20 to 50 microns and a specific gravity of less than 2.5; and   (ii) Precipitating the radionuclide as an insoluble salt into the particulate material, wherein the radionuclide is an insoluble salt of an isotope selected from the group consisting of yttrium, holmium, samarium, iodine, phosphorus, iridium or rhenium and wherein the radionuclide is incorporated such that there is less than 0.4% unbound or unprecipitated radionuclide.   
     
     
         25 . A process according to  claim 24 , wherein the radionuclide is precipitated as a phosphate salt. 
     
     
         26 . A process according to  claim 24 , wherein the particulate material is washed to remove un precipitated or loosely adherent radionuclide.