Particulate Materials And Compositions For Radio Therapy

Abstract

Timed-bioresorbable particulates, particularly microspheres or fibers, may be used as a vehicle for delivery of radioisotopes, such as Y-90 and Pd-103 for localized radiotherapy, or as an embolic device. These particulates may also be embedded in polymers, or dispersed in injectable gels or other injectable media for the treatment of various cancers. The benefit of bioresorption, the ability to control the ratio of radioisotopes in the particulate, especially the gamma and beta ratios such as In-111/Y-90 ratio in a particulate, and the benefit of non-conductive implants are disclosed.

1 - 35 . (canceled) 
     
     
         36 . A suspension comprising a matrix suspended or dispersed in viscous medium, tissue adhesive medium, iodized medium, or gel medium, wherein said matrix comprises radioactive isotopes. 
     
     
         37 . The suspension of  claim 36 , wherein said radioactive isotopes are Y-90, In-111, Pd-103, P-32, Cs-131, Sm-153, Ho-166, Tc-99m, Yb-169, Au-198, Re-188, Re-186, Ir-192, Lu-177, Ba-140, Se-72, 1-131, 1-125, Sr-90, Dy-165, Er, Tl, Sr, Gd, Y-90/In-111, Y-90/Tc-99m, P-32/In-111, P-32/Tc-99m, Ho-166/In-111, Ho-166/Tc-99m, Sm-153/In-111, Sm-153/Tc-99m, or combinations thereof. 
     
     
         38 . The suspension of  claim 36 , wherein said radioactive isotopes are present in an amount effective for radiation therapy of a tumor. 
     
     
         39 . The suspension of  claim 36 , wherein said matrix is a particulate, microsphere, porous microsphere, hollow microsphere, microcapsule, solid or porous fiber, small solid or porous rod, particulate dispersed in biopolymers, particulate dispersed in bioresorbable sutures, particulate dispersed in biocompatible gels, particulate dispersed in other media, or combinations thereof. 
     
     
         40 . The suspension of  claim 36 , wherein said viscous medium is pyrogen-free 85% glycerol. 
     
     
         41 . The suspension of  claim 36 , wherein said iodized medium is iodized lipiodol. 
     
     
         42 . The suspension of  claim 36 , wherein said matrix is a microsphere that comprises Yttrium-90. 
     
     
         43 . The suspension of  claim 42 , wherein said microsphere is solid, porous, or hollow. 
     
     
         44 . The suspension of  claim 36 , wherein said matrix comprises oxides, oxides containing nitrogen, nitrides, or combinations thereof. 
     
     
         45 . A resorbable implant material comprising: (i) a resorbable base oxide matrix which is biocompatible; and (ii) a nitrogen-rich surface layer formed on the resorbable base oxide matrix, the surface layer being of greater durability than the base oxide matrix. 
     
     
         46 . The implant material of  claim 45 , wherein the nitrogen-rich layer comprises about 15% molar nitrogen. 
     
     
         47 . The implant material of  claim 45 , wherein the base oxide matrix is oxide fibers, oxide microspheres or oxide particulates. 
     
     
         48 . The implant material of  claim 45 , wherein durability of the implant material is controlled by base oxide composition, nitrogen content or combination thereof. 
     
     
         49 . The implant material of  claim 45 , wherein the base oxide matrix is phosphate and borate or phosphate and silicate, wherein P 2 O 5 +B 2 O 3  and P 2 O 5 +SiO 2  content is in the range of 30% to 95%. 
     
     
         50 . The implant material of  claim 45 , wherein said implant material is embedded in a non-conductive delivery vehicle. 
     
     
         51 . The implant material of  claim 50 , wherein said non-conductive delivery vehicle is a biopolymer, bioresorbable suture, injectable gel, tissue adhesive, other media, or combinations thereof. 
     
     
         52 . The implant material of  claim 47 , wherein said oxide fibers, oxide microspheres or oxide particulates are embedded in poly-l-lactic acid in the molecular weight range of 30,000 to 500,000, poly-l-lactic acid co-polymers with polyglycolic acid, polydioanone (PDS II), polyglycaprone 25 (Moncryl), polyglactin 910 (Vicryl), phenyletheretherketone (PEEK), polysulfone (PSU), polyurethane, polypropylene, silicone, polyethylene terephthalate (PET), polyphenylene oxide blends (PPO), polyphenylsulfone (PPSU), polyether sulfone (PES), polyphenylene sulfide (PPS), polyetherimide (PEI), liquid crystal polymer (LCP), or combinations thereof. 
     
     
         53 . A method of radiotherapy comprising administering the suspension of  claim 36  to an individual. 
     
     
         54 . A method of making the resorbable implant material of  claim 45  comprising treating said resorbable base oxide matrix in ammonia. 
     
     
         55 . The implant material of  claim 47 , wherein said oxide fibers, oxide microspheres or oxide particulates are solid, porous, or hollow.