Patents by Inventor Dag Lindstrom

Dag Lindstrom 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: 8309709
    Abstract: The present invention relates to a method of preparing an insoluble separation matrix, which method comprises salt-treatment of a polysaccharide gel followed by cross-linking of the polysaccharide polymers. In one embodiment, the method comprises providing an aqueous solution of a gelatable native polysaccharide; lowering the temperature of the polysaccharide solution to a value below its gelling point; salt-treatment by adding at least one salt to the resulting polysaccharide; and cross-linking the salt-treated polysaccharide. The polysaccharide may be prepared e.g. into particles, membranes or monoliths.
    Type: Grant
    Filed: June 28, 2006
    Date of Patent: November 13, 2012
    Assignee: GE Healthcare Bio-Sciences AB
    Inventors: Hans Berg, Maria Brannholm, David Buckley, Philippe Busson, Anders Hagvall, Eva Holmgren, Henrik Ihre, Anders Larsson, Dag Lindstrom
  • Patent number: 8093373
    Abstract: The present invention relates to a method of isolating at least one plasmid from other components of a liquid, which method comprises the steps of providing a separation matrix comprised of one or more porous carriers, which carrier(s) present anion exchange groups on external surfaces as well as pore surfaces and a pore size distribution that does not allow access of plasmids to pore surfaces; contacting said matrix with the liquid to allow adsorption of the plasmids to ligands present on the separation matrix; contacting an eluent with the separation matrix to release the plasmids and recovering plasmids from a fraction of said eluent. Thus, the present method allows the plasmids to adsorb to the external surfaces of the matrix, while other components such as RNA is adsorbed onto the pore surfaces. In one embodiment, the matrix presents a DNA exclusion limit of at least about 270 base pairs; such as at least about 1,000 base pairs.
    Type: Grant
    Filed: February 21, 2005
    Date of Patent: January 10, 2012
    Assignee: GE Healthcare Bio-Sciences AB
    Inventors: James Van Alstine, Jan Bergström, Dag Lindström, Joachim Stadler
  • Patent number: 7897257
    Abstract: The present invention relates to magnetic beads suitable for, for example, isolation of proteins, cells, and viruses and also for diagnostic applications and cell cultivation. The magnetic beads are composite beads with an inner core of metal particles, which are coated with an inert synthetic polymer and these are then enclosed in a hydrophilic porous polymer, preferably agarose. This provides porous biocompatible beads without metal leakage. The beads may be used for cell cultivation or for chromatography. When the beads are used for chromatography the agarose layer is preferably provided with ligands having affinity for selected biomolecules.
    Type: Grant
    Filed: April 13, 2006
    Date of Patent: March 1, 2011
    Assignee: GE Healthcare Bio-Sciences AB
    Inventors: Mathias Alterman, Andreas Axen, Gunnar Glad, Dag Lindstrom, Ulrika Meyer, Nils Norrman, Tobias Soderman
  • Patent number: 7396467
    Abstract: The present invention relates to a method of preparing a porous cross-linked polysaccharide chromatography matrix, which comprises to provide an aqueous solution of a gellable polysaccharide, wherein part of the hydroxyl groups are substituted with groups which are not susceptible to nucleophilic attack; to provide essentially spherical droplets of the substituted polysaccharide solution; to form a gel of the substituted polysaccharide solution; and to cross-link the gel by adding a cross-linking agent. The invention also encompasses a chromatography column packed with a matrix so produced as well as use thereof in e.g. protein purification.
    Type: Grant
    Filed: October 13, 2004
    Date of Patent: July 8, 2008
    Assignee: GE Healthcare Bio-Sciences AB
    Inventors: Hans Berg, David Buckley, Maria Brännholm, Anders Hagvall, Henrik Ihre, Eva Holmgren, Anders Larsson, Dag Lindstrom
  • Publication number: 20080154031
    Abstract: The present invention relates to a method of preparing an insoluble separation matrix, which method comprises salt-treatment of a polysaccharide gel followed by cross-linking of the polysaccharide polymers. In one embodiment, the method comprises providing an aqueous solution of a gelatable native polysaccharide; lowering the temperature of the polysaccharide solution to a value below its gelling point; salt-treatment by adding at least one salt to the resulting polysaccharide; and cross-linking the salt-treated polysaccharide. The polysaccharide may be prepared e.g. into particles, membranes or monoliths.
    Type: Application
    Filed: June 28, 2006
    Publication date: June 26, 2008
    Applicant: GE HEALTHCARE BIO-SCIENCES AB
    Inventors: Hans Berg, Maria Brannholm, David Buckley, Philippe Busson, Anders Hagvall, Eva Holmgren, Henrik Ihre, Anders Larsson, Dag Lindstrom
  • Publication number: 20080152939
    Abstract: The present invention relates to magnetic beads suitable for, for example, isolation of proteins, cells, and viruses and also for diagnostic applications and cell cultivation. The magnetic beads are composite beads with an inner core of metal particles, which are coated with an inert synthetic polymer and these are then enclosed in a hydrophilic porous polymer, preferably agarose. This provides porous biocompatible beads without metal leakage. The beads may be used for cell cultivation or for chromatography. When the beads are used for chromatography the agarose layer is preferably provided with ligands having affinity for selected biomolecules.
    Type: Application
    Filed: April 13, 2006
    Publication date: June 26, 2008
    Applicant: GE Healthcare Bio-Sciences AB
    Inventors: Mathias Alterman, Andreas Axen, Gunnar Glad, Dag Lindstrom, Ulrika Meyer, Nils Norrman, Tobias E. Soderman
  • Publication number: 20070161000
    Abstract: The present invention relates to a method of isolating at least one plasmid from other components of a liquid, which method comprises the steps of providing a separation matrix comprised of one or more porous carriers, which carrier(s) present anion exchange groups on external surfaces as well as pore surfaces and a pore size distribution that does not allow access of plasmids to pore surfaces; contacting said matrix with the liquid to allow adsorption of the plasmids to ligands present on the separation matrix; contacting an eluent with the separation matrix to release the plasmids and recovering plasmids from a fraction of said eluent. Thus, the present method allows the plasmids to adsorb to the external surfaces of the matrix, while other components such as RNA is adsorbed onto the pore surfaces. In one embodiment, the matrix presents a DNA exclusion limit of at least about 270 base pairs; such as at least about 1,000 base pairs.
    Type: Application
    Filed: February 21, 2005
    Publication date: July 12, 2007
    Inventors: James Van Alstine, Jan Bergstrom, Dag Lindstrom, Joachim Stadler
  • Patent number: 7208532
    Abstract: A method for the production of a cross-linked support matrix that in form of a bed will permit liquid flow velocities above 5 cm/h, preferably above 50 cm/h, to pass through the bed. The method is characterized in that it comprises the steps: (a) providing a starting support matrix that has pendent unsaturated groups, and (b) subjecting said starting support matrix to electron beam or gamma-ray irradiation. The use of a cross-linked support matrix produced by a method comprising the steps of: (a) providing a starting support matrix that has pendent unsaturated groups, and (b) subjecting said starting support matrix to electron beam or gamma-ray irradiation as a support matrix in liquid chromatography, cell culturing, step-wise solid phase synthesis of organic compounds, running catalytic reactions by the use of a solid phase bound catalyst.
    Type: Grant
    Filed: December 11, 2000
    Date of Patent: April 24, 2007
    Assignee: GE Healthcare Bio-Sciences AB
    Inventors: Eva Berggren, Dag Lindstrom
  • Publication number: 20060060534
    Abstract: The present invention relates to a method of preparing a porous cross-linked polysaccharide chromatography matrix, which comprises to provide an aqueous solution of a gellable polysaccharide, wherein part of the hydroxyl groups are substituted with groups which are not susceptible to nucleophilic attack; to provide essentially spherical droplets of the substituted polysaccharide solution; to form a gel of the substituted polysaccharide solution; and to cross-link the gel by adding a cross-linking agent. The invention also encompasses a chromatography column packed with a matrix so produced as well as use thereof in e.g. protein purification.
    Type: Application
    Filed: October 13, 2004
    Publication date: March 23, 2006
    Inventors: Hans Berg, David Buckley, Maria Brannholm, Anders Hagvall, Henrik Ihre, Eva Holmgren, Anders Larsson, Dag Lindstrom
  • Publication number: 20030144127
    Abstract: A method for the production of a cross-linked support matrix that in form of a bed will permit liquid flow velocities above 5 cm/h, preferably above 50 cm/h, to pass through the bed. The method is characterized in that it comprises the steps: (a) providing a starting support matrix that has pendent unsaturated groups, and (b) subjecting said starting support matrix to electron beam or gamma-ray irradiation. The use of a cross-linked support matrix produced by a method comprising the steps of: (a) providing a starting support matrix that has pendent unsaturated groups, and (b) subjecting said starting support matrix to electron beam or gamma-ray irradiation as a support matrix in liquid chromatography, cell culturing, step-wise solid phase synthesis of organic compounds, running catalytic reactions by the use of a solid phase bound catalyst.
    Type: Application
    Filed: September 9, 2002
    Publication date: July 31, 2003
    Inventors: Eva Berggren, Dag Lindstrom