Patents Represented by Attorney, Agent or Law Firm George A. Frank
  • Metal oxide stabilized chromatography packings
    Patent number: 4600646
    Abstract: Surface-stabilized porous silica having discontinuous metal oxide layer over the silica, chromatographic packings based on the metal-stabilized silica and processes for their preparation, are provided. The chromatographic packings so provided have increased life time.
    Type: Grant
    Filed: August 15, 1984
    Date of Patent: July 15, 1986
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Richard W. Stout
  • Thick film copper compatible resistors based on hexaboride conductors and nonreducible glasses
    Patent number: 4585580
    Abstract: Thick flim resistors and conductors compatible with copper and fireable in nonoxidizing atmosphere are provided. The resistors are based on certain hexaboride conductors such as LaB.sub.6 and glasses which are thermodynamically stable to or nonreducible by the hexaborides. Thick film pastes prepared with small particle size hexaboride and certain ethylene-vinyl acetate polymeric vehicles afford resistors having improved temperature coefficient of resistance and coefficient of variation.
    Type: Grant
    Filed: August 16, 1978
    Date of Patent: April 29, 1986
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Paul C. Donohue
  • Polyether polyamines as linking agents for particle reagents useful in immunoassays
    Patent number: 4581337
    Abstract: Particle reagents, having polyether polyamine linking groups, for use in turbidimetric immunoassays are provided. These linking agents permit ready covalent attachment of compounds of biological interest to polymer particles and lead to immunoassays of improved precision.
    Type: Grant
    Filed: July 7, 1983
    Date of Patent: April 8, 1986
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: William A. Frey, Donald M. Simons
  • Heterogeneous immunoassay for digoxin using ouabain as a separation means
    Patent number: 4551426
    Abstract: A heterogeneous immunoassay for digoxin. An excess of labeled anti-digoxin antibody is added to a test sample and the resulting reaction mixture is contacted with a solid phase having ouabain immobilized thereon. All the free, labeled antibody binds to the oubain. The eluted digoxin anti-digoxin antibody complex is measured for label activity. A competitive mode is also disclosed.
    Type: Grant
    Filed: January 18, 1984
    Date of Patent: November 5, 1985
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: William J. Freytag, Shung-Ho Chang
  • Hybridoma cell lines and monoclonal antibodies to theophylline
    Patent number: 4524025
    Abstract: Monoclonal antibodies to theophylline having 5% or less cross-reactivity with caffeine and the continuous hybrid monoclonal cell lines for their production are provided. These antibodies are useful in a particle-enhanced turbidimetric inhibition immunoassay for theophylline.
    Type: Grant
    Filed: August 9, 1982
    Date of Patent: June 18, 1985
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: John E. Geltosky
  • Turbidimetric method for measuring protein in urine and cerebrospinal fluid
    Patent number: 4485176
    Abstract: Improvements in the quantitative measurement of protein in urine and cerebrospinal fluid are provided by adding the assay reagents in two discrete steps and increasing the concentration of cationic surfactant. The method measures protein concentration based upon the turbidity produced in the presence of a cationic surfactant in an alkaline environment.
    Type: Grant
    Filed: June 28, 1982
    Date of Patent: November 27, 1984
    Assignee: E. I. Du Pont de Nemours & Company
    Inventors: Ernest Bollin, Jr., Richard S. Schifreen
  • Method for the removal of interfering substances in theophylline assays
    Patent number: 4477346
    Abstract: An apparatus for the separation of theophylline and caffeine contained in body fluids is provided. A macroreticular styrene-divinylbenzene copolymer resin activated by a protic solvent is utilized. The body fluid is eluted with water in an isocratic manner to afford a theophylline sample uncontaminated with caffeine. Such samples are useful in immunoassay procedures for the measurement of theophylline.
    Type: Grant
    Filed: April 22, 1983
    Date of Patent: October 16, 1984
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Johanne C. Dickinson, William A. Frey
  • Immunoglobulin half-molecules and process for producing hybrid antibodies
    Patent number: 4470925
    Abstract: A process for preparing covalent hybrid antibodies is provided. These antibodies are obtained by the ordered covalent hybridization of intact immunoglobulin molecules. The generation of half-molecules from different IgG antibodies by reductive or S-sulfonation selective cleavage is followed by the ordered association of the different half-molecules. The pure covalent hybrid antibodies as new substances are also provided along with IgG half-molecules.
    Type: Grant
    Filed: October 4, 1983
    Date of Patent: September 11, 1984
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Karen Auditore-Hargreaves
  • Method for the removal of interfering substances, including caffeine, in theophylline assays
    Patent number: 4460695
    Abstract: A method for the separation of theophylline and caffeine contained in body fluids is provided. A macroreticular styrene-divinylbenzene copolymer resin activated by a protic solvent is utilized. The body fluid is eluted with water in an isocratic manner to afford a theophylline sample uncontaminated with caffeine. Such samples are useful in immunoassay procedures for the measurement of theophylline.
    Type: Grant
    Filed: December 24, 1981
    Date of Patent: July 17, 1984
    Assignee: E. I. DuPont de Nemours and Company
    Inventors: Johanne C. Dickinson, William A. Frey
  • Process for producing simulated wooden articles
    Patent number: 4181763
    Abstract: A non-chemical, mechanical process for antiquing wood applying a high temperature flame to the surface of a variety of woods for short periods of time, is provided. The processed pieces of variously shaped wood can be coated and are useful as decorative articles and home furnishings.
    Type: Grant
    Filed: June 27, 1977
    Date of Patent: January 1, 1980
    Inventor: Robert L. Shellenberger