Patents by Inventor Garland E. Twitty

Garland E. Twitty 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: 6210574
    Abstract: A system for separating nucleated cells from a blood sample includes a charge-flow separator (CFS), which separates blood into fractions according to the surface charge density characteristics coupled with an affinity-filtration separator which either outputs a separated blood fraction to the CFS or receives a separated blood fraction from the CFS. The system permits separation of nucleated fetal red blood cells, erythroid progenitor cells and other nucleated cells found in blood samples.
    Type: Grant
    Filed: May 24, 1999
    Date of Patent: April 3, 2001
    Assignee: BioSeparations, Inc.
    Inventors: David W. Sammons, Garland E. Twitty, Joseph G. Utermohlen, Rizwan Sharnez
  • Patent number: 5948278
    Abstract: A method for enriching rare cell populations from a whole blood sample by separating rare cell fractions from whole blood sample according to the relative charge density and/or the relative binding affinity for a leukocyte depletion solid phase matrix is described. The enrichment method may be operated stand alone, or as a pre or post-processing step in conjunction with a charge-flow separation method.
    Type: Grant
    Filed: October 10, 1997
    Date of Patent: September 7, 1999
    Assignee: BioSeparations, Inc.
    Inventors: David W. Sammons, Michael Manley, Joseph G. Utermohlen, Garland E. Twitty
  • Patent number: 5906724
    Abstract: A charge-flow separation apparatus (CFS) for enriching rare cell populations, particularly fetal cells, from a whole blood sample by separating the rare cell fractions from whole fractions according to the relative-charge density and/or the relative binding affinity for a leukocyte depletion solid phase matrix is described. The apparatus having an internal cooling system allows for dissipating heat generated by the electric field of the apparatus. The internal cooling system, consisting of a plurality of cooling tubes to circulate coolant material, prevents cellular degradation typically associated with the high heat generated by the electric field and permits the use of a higher voltage gradient to shorten separation times.
    Type: Grant
    Filed: July 23, 1997
    Date of Patent: May 25, 1999
    Assignee: BioSeparations, Inc.
    Inventors: David W. Sammons, Garland E. Twitty, Joseph G. Utermohlen, Rizwan Sharnez
  • Patent number: 5676849
    Abstract: A method for enriching rare cell populations from a whole blood sample by separating rare cell fractions from whole according to the relative charge density and/or the relative binding affinity for a leukocyte depletion solid phase matrix. The enrichment method may be operated stand alone, or as a pre or post-processing step in conjunction with a charge-flow separation method.
    Type: Grant
    Filed: March 8, 1995
    Date of Patent: October 14, 1997
    Assignee: BioSeparations, Inc.
    Inventors: David W. Sammons, Michael Manley, Joseph G. Utermohlen, Garland E. Twitty
  • Patent number: 5662813
    Abstract: A charge-flow separation apparatus (CFS) and method for enriching rare cell populations, particularly fetal cells, from a whole blood sample by separating the rare cell fractions from whole according to the relative charge density and/or the relative binding affinity for a leukocyte depletion solid phase matrix. The enrichment method may be operated stand alone, or as a pre- or post-processing step in conjunction with a charge-flow separation method.
    Type: Grant
    Filed: October 21, 1994
    Date of Patent: September 2, 1997
    Assignee: BioSeparations, Inc.
    Inventors: David W. Sammons, Garland E. Twitty, Joseph G. Utermohlen, Rizwan Sharnez
  • Patent number: 5336387
    Abstract: A preparative scale electrical separator, which is matrix-free and may be operated in both a batch mode and a continuous, flow-through mode is provided. It may be scaled according to the solution quantities which are to be processed. An internal cooling system whereby the process fluid is always in close proximity to a chilled surface assures an efficient heat dissipation during the separation and concentration processes and also allows the use of higher voltage gradients and shorter separation times than prior designs of electrophoretic separators. Electroosmotic and convective mixing is reduced by providing internal, compartmentation of sample fractions, focusing is improved and focusing times are decreased. A counter-flow gradient focusing method using the electrophoretic separator allows for separation of cells from human or animal blood and tissues, cells from plants, bacteria and viruses.
    Type: Grant
    Filed: November 16, 1992
    Date of Patent: August 9, 1994
    Assignee: BioSeparations, Inc.
    Inventors: Ned B. Egen, Garland E. Twitty, David W. Sammons
  • Patent number: 5173164
    Abstract: A preparative scale multi-mode electrical separator, which is matrix-free and may be operated in both a batch mode and a continuous, flow-through mode is provided. It may be scaled according to the solution quantities which are to be processed. An internal cooling system whereby the process fluid is always in close proximity to a chilled surface assures an efficient heat dissipation during the separation and concentration processes and also allows the use of higher voltage gradients and shorter separation times than prior designs of electrophoretic separators. Electroosmotic mixing is reduced by providing internal, compartmentation of sample fractions, focusing is improved and focusing times are decreased. Different electrophoretic methods, including zone electrophoresis, isoelectric focusing, counterflow gradient focusing or electrodialysis, may be used with the separator. It may be applied to the purification of proteins, ions, and microorganisms, and for water purification.
    Type: Grant
    Filed: September 11, 1990
    Date of Patent: December 22, 1992
    Assignee: Bioseparations, Inc.
    Inventors: Ned B. Egen, Garland E. Twitty, David W. Sammons, Rizwan Sharnez
  • Patent number: 4897169
    Abstract: The disclosure is directed to a process and apparatus for isoelectric focusing and isotachophoresis of fluids. Recycling of the process fluid is established in a first direction through an electrophoretic chamber having parallel walls, the electric field being applied in a second direction. Externally of the chamber, the flow of fluid is subdivided into a plurality of closed loops, cooled to dissipate the Joule heat. While maintaining conditions of laminar flow within the chamber, unusual fluid stabilization against convective, electroosmotic and other fluid flow disturbances is obtained if the gap between the parallel walls of the chamber is kept narrow and the fluid flow is rapid, to maximize shear stress at the walls of the chamber and minimize the fluid residence time in the chamber.
    Type: Grant
    Filed: April 3, 1989
    Date of Patent: January 30, 1990
    Inventors: Milan Bier, Garland E. Twitty