Low-density magnesia-alumina-silica (MAS) microparticles for radiotherapy and/or radioimaging

1. Microparticles for radio-imaging or radiation therapy in a mammal, comprising biologically compatible magnesia-alumina-silica glass microparticles, said microparticles containing at least one beta or gamma radiation emitting isotope distributed substantially throughout the magnesia-alumina-silica glass which emits an amount of beta or gamma radiation, the microparticles having a chemical durability such that subsequent to administration of the microparticles to the mammal, the microparticles will not release a significant amount of the radioisotope into the mammal's system wherein the glass microparticles comprise approximately 8-14 wt % MgO, 32-35 wt % Al 2 O 3 , and 47-52 wt % SiO 2 .

2. The microparticles of claim 1 , wherein the microparticles have a density of about 3.0 g/ml or less.

3. The microparticles of claim 1 having a size range from about 20 to 200 um.

4. The microparticles of claim 2 having a size range from about 20 to 200 um.

5. The microparticles of claim 1 having a density of about 2.8.

6. The microparticles of claim 1 wherein the microparticles are microspheres.

7. The microparticles of claim 1 wherein the microparticles contain gallium-68 or fluorine-18 distributed substantially throughout the magnesia-alumina-silica glass.

8. A method of administering radioactive magnesia-alumina-silica glass microparticles to a patient in need thereof, comprising delivering by catheter to an artery that feeds an organ or a tumor of a patient a composition comprising the radioactive microparticles of claim 1 , and a physiologically acceptable carrier.

9. The method according to claim 8 wherein the glass microparticles contain gallium-68 or fluorine-18 distributed substantially throughout the microparticles.

10. The method according to claim 8 wherein the microparticles have a density of about 3.0 g/ml or less.

11. The method according to claim 8 wherein the microparticles have a size ranging from about 20 to 200 um.

12. The method according to claim 10 wherein the microparticles have a size ranging from about 20 to 200 um.

13. The method of claim 8 wherein the microparticles are microspheres.

14. The method of claim 8 , wherein the organ or tumor is selected from the group consisting of liver, spleen, brain, kidney, head & neck, uterine, and prostate.

15. A method of obtaining a radiologic image of an organ or tumor in a patient, comprising administering by catheter to an artery that feeds an organ or tumor of a patient a composition containing magnesium-alumina-silicate glass microparticles according to claim 1 in a physiologically acceptable carrier, and obtaining the radiologic image of the patient's organ or tumor.

16. The method of claim 15 , further comprising wherein the radionuclide imaging technique is single photon emission computed tomography (SPECT).

17. The method according to claim 16 wherein the glass microparticles comprise gallium-68 or fluorine-18 distributed substantially throughout the microparticles.

18. The microparticles of claim 1 wherein the at least one beta or gamma radiation emitting radioisotope is Dysprosium-165.

19. The microparticles of claim 1 wherein the at least one beta or gamma radiation emitting radioisotope is Samarium-153.

20. The microparticles of claim 1 wherein the at least one beta or gamma radiation emitting radioisotope is Yttrrium-90.

21. The microparticles of claim 1 wherein the microparticles are microspheres having a particle size of from about 5 to about 75 micrometers.