Patents by Inventor Gary J. Ehrhardt

Gary J. Ehrhardt has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6222896
    Abstract: Methods for the production of radionuclides suitable for use in radiopharmaceuticals for diagnostic and therapeutic applications, and specifically, to the production of 186Re, 188Re and other radionuclides such as 195mPt and 198Au using an inorganic Szilard-Chalmers reaction. Thin-film and powdered 185 or 187Reo metal targets, and 185 or 187Re oxide/metal oxide target compositions with rhenium in a lower, relatively reduced oxidation state are prepared. The thin-film rhenium targets are aged for at least about 24 hours and then irradiated with neutrons in the present of an oxidizing medium sufficient to form a product nuclide in the higher oxidized state of perrhenate, ReO4−. Significantly, the rate and/or extent of oxidation of target nuclides which do not react with a neutron is controlled. For example, oxidation of such non-bombarded target nuclides is minimized by irradiating under vacuum, controlling the amount of oxidizing agent present, cooling during irradiation, etc.
    Type: Grant
    Filed: September 11, 1998
    Date of Patent: April 24, 2001
    Assignee: The Curators of the University of Missouri
    Inventors: Wei Jia, Gary J. Ehrhardt
  • Patent number: 5862193
    Abstract: Methods for the production of radionuclides suitable for use in radiopharmaceuticals for diagnostic and therapeutic applications, and specifically, to the production of .sup.186 Re, .sup.188 Re and other radionuclides such as .sup.195m Pt and .sup.198 Au using an inorganic Szilard-Chalmers reaction. Thin-film and powdered .sup.185 or 187 Re.degree. metal targets, and .sup.185 or 187 Re oxide/metal oxide target compositions with rhenium in a lower, relatively reduced oxidation state are prepared. The thin-film rhenium targets are aged for at least about 24 hours and then irradiated with neutrons in the present of an oxidizing medium sufficient to form a product nuclide in the higher oxidized state of perrhenate, ReO.sub.4.sup.-. Significantly, the rate and/or extent of oxidation of target nuclides which do not react with a neutron is controlled.
    Type: Grant
    Filed: August 20, 1997
    Date of Patent: January 19, 1999
    Assignee: The Curators of the University of Missouri
    Inventors: Wei Jia, Gary J. Ehrhardt
  • Patent number: 5403573
    Abstract: A radiolabeled protein composition adapted for radiation therapy which comprises a radioisotope and a protein material containing about 6 or more percent amino acids which have a sulfhydryl-containing side chain. A method for carrying out radiation synovectomy of arthritic joints. Rhenium radiolabeled protein microspheres are administered which contain cysteine and other amino acids. A method for radiolabeling a protein composition whereby the composition is treated with a reducing agent capable of reducing disulfides to sulfhydryls prior to radiolabeling.
    Type: Grant
    Filed: April 23, 1992
    Date of Patent: April 4, 1995
    Assignee: The Curators of the University of Missouri
    Inventors: Delbert E. Day, Gary J. Ehrhardt, Kurt R. Zinn
  • Patent number: 5382388
    Abstract: Process for preparing a radionuclide generator for producing Tc-99m or Re-188. A clear solution containing a metallic cation and an anion comprising W-188 or Mo-99 is provided. The metallic cation is present in the solution as a dissolved complex of the metallic cation and a complexing agent and/or the anion being present in the solution as a dissolved complex of the anion and a complexing agent. The dissolved complex(es) are decomposed to form a slurry containing a precipitate of the metallic cation and the anion. The precipitate is transferred to an elutable container of a radionuclide generator.
    Type: Grant
    Filed: August 21, 1992
    Date of Patent: January 17, 1995
    Assignees: Curators of University of Missouri, Mallinckrodt Medical, Inc.
    Inventors: Gary J. Ehrhardt, Robert G. Wolfangel, Edward A. Deutsch
  • Patent number: 5302369
    Abstract: Microspheres for radiation therapy of a mammal which have a non-radioactive isotope which emits beta or gamma radiation of therapeutic intensity upon being irradiated. The microspheres also contain elements which do not become radioactive upon irradiation. The chemical durability of the microspheres is such that they do not release a significant amount of radiation emitting radioisotope into the mammal's system upon administration. Microspheres containing phosphorus or yttrium; and carbon, nitrogen, fluorine, sodium, magnesium, aluminum, silicon, potassium, vanadium, manganese, gallium, niobium, iodine and/or lead.
    Type: Grant
    Filed: August 29, 1991
    Date of Patent: April 12, 1994
    Assignee: The Curators of the University of Missouri
    Inventors: Delbert E. Day, Gary J. Ehrhardt
  • Patent number: 5154897
    Abstract: A method and a generator for separating daughter radioisotope from a stock solution containing the daughter radioisotope and its parent are provided. The generator is provided with a glass adsorbent which preferentially adsorbs daughter radioisotope relative to the parent radioisotope and circulation means for withdrawing the stock solution from a reservoir, contacting the solution with the glass adsorbent to adsorb the daughter radioisotope and returning the parent radioisotope-enriched solution to the reservoir. In the process stock solution containing daughter radioisotope having a predetermined pH is contacted with the glass adsorbent to selectively adsorb the daughter radioisotope thereon and the daughter radioisotope is eluted with an eluant at a second predetermined pH. The process also includes a step of washing the glass adsorbent with a wash solution at the first predetermined pH to remove traces of the parent radioisotope from the adsorbent prior to eluting the daughter radioiotope.
    Type: Grant
    Filed: March 6, 1991
    Date of Patent: October 13, 1992
    Assignee: University of Missouri
    Inventors: Gary J. Ehrhardt, Robert K. Guimon, Kurt R. Zinn, Steven Symes
  • Patent number: 5145636
    Abstract: Water soluble irradiation targets are disclosed for the production of .sup.186 Re and .sup.188 Re. The irradiation targets are selected for both water solubility and absence of elements which would produce contaminating isotopes for medical therapeutic and diagnostic use. In one embodiment, .sup.186 Re or 188Re is produced by the direct irradiation of a water soluble irradiation target comprising .sup.185 Re or .sup.187 Re, respectively. Preferred targets for this purpose include aluminum perrhenate, lithium perrhenate and magnesium perrhenate. In another embodiment, a zirconyl tungstate generator comprising .sup.188 W for the production of .sup.188 Re is obtained by irradiating a soluble irradiation target comprising .sup.186 W, dissolving the irradiated target in aqueous solution, reacting the dissolved target with an aqueous solution comprising zirconyl ion to form an insoluble zirconium tungstate precipitate and disposing the precipitate in an elutable container.
    Type: Grant
    Filed: June 18, 1991
    Date of Patent: September 8, 1992
    Assignees: NeoRx Corporation, Curators of the University of Missouri
    Inventors: Jean-Luc E. Vanderhevden, Fu-Min Su, Gary J. Ehrhardt
  • Patent number: 5053186
    Abstract: Water soluble irradiation targets are disclosed for the production of .sup.186 Re and .sup.188 Re. The irradiation targets are selected for both water solubility and absence of elements which would produce contaminating isotopes for medical therapeutic and diagnostic use. In one embodiment, .sup.186 Re or .sup.188 Re is produced by the direct irradiation of a water soluble irradiation target comprising .sup.185 Re or .sup.187 Re, respectively. Preferred targets for this purpose include aluminum perrhenate, lithium perrhenate and magnesium perrhenate. In another embodiment, a zirconyl tungstate generator comprising .sup.188 W for the production of .sup.186 Re is obtained by irradiating a soluble irradiation target comprising .sup.186 W, dissolving the irradiated target in aqueous solution, reacting the dissolved target with an aqueous solution comprising zirconyl ion to form an insoluble zirconium tungstate precipitate and disposing the precipitate in an elutable container.
    Type: Grant
    Filed: October 2, 1989
    Date of Patent: October 1, 1991
    Assignees: NeoRx Corporation, The Curators of the University of Missouri
    Inventors: Jean-Luc E. Vanderheyden, Fu-Min Su, Gary J. Ehrhardt
  • Patent number: 5039326
    Abstract: A method for preparing nonradioactive microspheres adapted for radiation synovectomy of arthritic joints in a mammal involves forming the microspheres by doping a biodegradable glass material which may be lithium or potassium silicate, lithium or potassium aluminosilicate, lithium or potassium aluminoborate, lithium or potassium germanate or lithium or potassium aluminogermanate with an isotope which may be samarium, holmium, erbium, dysprosium, rhemium or yttrium so that the isotope is chemcially dissolved in and distributed uniformly throughout the glass material. The doped glass material is then treated with an acid wash to produce a thin layer on the surface thereof and heat treated to improve the chemical durability of the glass material by rendering the solubility of the layer lower than that of the underlying glass material.
    Type: Grant
    Filed: September 15, 1989
    Date of Patent: August 13, 1991
    Assignee: The Curators of the University of Missouri
    Inventors: Delbert E. Day, Gary J. Ehrhardt
  • Patent number: 5011797
    Abstract: Radioactive microspheres for radiation synovectomy of arthritic joints in a mammal comprises a biodegradable glass material and a beta radiation emitting radioisotope chemically dissolved in and distributed substantially uniformly throughout the glass material. The biodegradable glass material may be lithium silicate, lithium aluminosilicate, lithium aluminoborate, lithium germanate, lithium aluminogermanate, potassium silicate, potassium aluminosilicate, potassium aluminoborate, potassium germanate or potassium aluminogermanate and the beta radiation emitting radioisotope may be samarium-153, holmium-166, erbium-169, dysprosium-165, rhenium-186, rhenium-188 or yttrium-90. Method for preparing such microspheres and for carrying out radiation synovectomy of arthritic joints utilizing such microspheres are also disclosed.
    Type: Grant
    Filed: September 15, 1989
    Date of Patent: April 30, 1991
    Assignee: The Curators of the University of Missouri
    Inventors: Delbert E. Day, Gary J. Ehrhardt
  • Patent number: 5011677
    Abstract: A radioactive microsphere for radiation therapy of a mammal comprising a biologically compatible glass material containing a beta or gamma emitting radioisotope distributed substantially uniformly throughout the glass. Advantageously, the radioisotope is produced by irradiation of the microsphere.
    Type: Grant
    Filed: August 18, 1988
    Date of Patent: April 30, 1991
    Assignee: The Curators of the University of Missouri
    Inventors: Delbert E. Day, Gary J. Ehrhardt
  • Patent number: 4889707
    Abstract: Radioactive microspheres for radiation synovectomy of arithmetic joints in a mammal comprise a biodegradable glass material and a beta radiation emitting radioisotope chemically dissolved in and distributed substantially uniformly throughout the glass material. The biodegradable glass material may be lithium silicate, lithium aluminosilicate, lithium aluminoborate, lithium germanate, lithium aluminogermanate, potassium silicate, potassium aluminosilicate, potassium, aluminoborate, potassium germanate or potassium aluminogermanate and the beta radiation emitting radioisotope may be samarium-153, holmium-166, erbium-169, dysprosium-165, rhenium-186, rhenium-188 or yttrium-90. Methods for preparing such microspheres and for carrying out radiation synovectomy of arthritic joints utilizing such microspheres are also disclosed.
    Type: Grant
    Filed: January 29, 1988
    Date of Patent: December 26, 1989
    Assignee: The Curators of the University of Missouri
    Inventors: Delbert E. Day, Gary J. Ehrhardt
  • Patent number: 4859431
    Abstract: A process for preparing a tungsten-188/rhenium-188 generator having a tungstate matrix containing W-188 produced by irradiating tungsten-186 in the tungstate compound. High activity, carrier-free rhenium-188 may be obtained by elution. Substrates for further purifying the rhenium-188 eluate are also described.
    Type: Grant
    Filed: January 25, 1988
    Date of Patent: August 22, 1989
    Assignee: The Curators of the University of Missouri
    Inventor: Gary J. Ehrhardt
  • Patent number: 4789501
    Abstract: A radioactive microsphere for radiation therapy of a mammal comprising a biologically compatible glass material containing a beta or gamma emitting radioisotope distributed substantially uniformly throughout the glass. Advantageously, the radioisotope is produced by irradiation of the microsphere.
    Type: Grant
    Filed: November 19, 1984
    Date of Patent: December 6, 1988
    Assignee: The Curators of the University of Missouri
    Inventors: Delbert E. Day, Gary J. Ehrhardt