Patents by Inventor Aharon S. Cohen

Aharon S. Cohen 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: 5665216
    Abstract: A capillary column for high performance electrophoretic separation and detection of SDS proteins and system for using the same is disclosed. A preferred column includes a capillary, a static or dynamic layer of coating material on the inner surface of the capillary wall, and a hydrophilic polymer network which is UV-transparent in the tube, filling it. The capillary column is particularly useful in any electrophoresis system requiring UV-transparent materials.
    Type: Grant
    Filed: October 7, 1991
    Date of Patent: September 9, 1997
    Assignee: Northeastern University
    Inventors: Barry L. Karger, Katalin Ganzler, Aharon S. Cohen
  • Patent number: 5643717
    Abstract: Disclosed is a substrate useful for separating unmodified and modified mononucleotides and oligonucleotides. The substrate includes at least 12% polymer in at least 50% (volume:volume) organic solvent, the organic solvent being a denaturing agent. This substrate is easily removable from the capillary using low pressure. Also provided is a method of separating unmodified and modified mononucleotides and oligonucleotides utilizing this substrate.
    Type: Grant
    Filed: March 16, 1993
    Date of Patent: July 1, 1997
    Assignee: Hybridon, Inc.
    Inventors: Aharon S. Cohen, Maria Vilenchik
  • Patent number: 5637464
    Abstract: Disclosed is a method of detecting a single-stranded target oligonucleotide in a biological fluid. In this method, a biological fluid sample to-be-tested is contacted with helper and primer oligonucleotides, thereby forming a labelled, double-stranded molecule if the sample contains an oligonucleotide which is complementary to the nucleotide sequences of the primer and the helper oligonucleotides. The primer so annealed to the target oligonucleotide is then ligated to the helper annealed to the target oligonucleotide. The presence of the ligation product is being indicative of the presence of the target oligonucleotide in the biological fluid.
    Type: Grant
    Filed: June 5, 1995
    Date of Patent: June 10, 1997
    Assignee: Hybridon, Inc.
    Inventors: Aharon S. Cohen, Alexei Belenky, Maria Vilenchik
  • Patent number: 5633129
    Abstract: The disclosure relates to a method for resolving double-stranded DNA species differing by at least one base pair. Each of the species is characterized by an iso-melting domain with a unique melting temperature contiguous with a melting domain of higher thermal stability.
    Type: Grant
    Filed: February 3, 1994
    Date of Patent: May 27, 1997
    Assignees: Massachusetts Institute of Technology, Northeastern University
    Inventors: Barry L. Karger, William G. Thilly, Frantisek Foret, Konstaintin Khrapko, Phouthone Koehavong, Aharon S. Cohen, Roger W. Giese
  • Patent number: 5627277
    Abstract: Disclosed is a substrate useful for separating unmodified and modified mononucleotides and oligonucleotides. The substrate includes at least 12% (weight:volume) polymer in at least 5M urea and at least 32% (volume:volume) organic solvent, the organic solvent being a chemically stable liquid at room temperature and having a dielectric constant of at least 20. Also provided is a method of separating unmodified and modified mononucleotides and/or oligonucleotides utilizing this substrate.
    Type: Grant
    Filed: January 7, 1994
    Date of Patent: May 6, 1997
    Assignee: Hybridon, Inc.
    Inventors: Aharon S. Cohen, Andre Bourque, Maria Vilenchik
  • Patent number: 5525470
    Abstract: Disclosed is a method for determining the nucleotide sequence of a target oligonucleotide. In this method a single-stranded ligation product is prepared which contains a target oligonucleotide-to-be sequenced and an auxiliary oligonucleotide. A primer complementary to a portion of the auxiliary oligonucleotide and having a label covalently attached thereto is annealed to the auxiliary oligonucleotide portion of the ligation product. The primer is extended with chain-extending nucleoside triphosphates and chain-terminating nucleoside triphosphates in the presence of a polymerase to yield a plurality of primer extension products. These extension products are then separated on the basis of their base length; and the nucleoside sequence of the target oligonucleotide is determined from the mobilities of the primer extension products obtained during their separation.
    Type: Grant
    Filed: January 26, 1994
    Date of Patent: June 11, 1996
    Assignee: Hybridon, Inc.
    Inventors: Aharon S. Cohen, Alexei Belenky, Christopher M. Ott
  • Patent number: 5506103
    Abstract: Disclosed is a method for detecting and quantitating oligonucleotides with charged internucleotide linkages in biological fluids. In this method, a biological fluid sample is contacted with an anion exchange resin at from 40.degree. C. to 65.degree. C. for a time sufficient to enable oligonucleotides in the sample to adsorb to the resin. The absorbed oligonucleotides are then desorbed with a buffer having a salt concentration of about 1 M to 2.5 M and a pH in the range of about 6.5 to 7.5, the desorption being performed at about 40.degree.-65.degree. C. The oligonucleotides so released are then detected and quantitated.
    Type: Grant
    Filed: November 16, 1993
    Date of Patent: April 9, 1996
    Assignee: Hybridon, Inc.
    Inventors: Aharon S. Cohen, Andre Bourque
  • Patent number: 5420265
    Abstract: A method for separating a mixture of 5'-phosphorothioate mononucleotides, a mixture of 5'-phosphorothioate oligonucleotides, or a mixture of both 5'-phosphorothioate mononucleotides and 5'-phosphorothioate oligonucleotides comprising electro- phoresis through a gel of at least 12% polymerized linear acrylamide containing at least 50% formamide or other denaturing organic solvent. This method can resolve phosphorothioate oligonucleotides differing by only a single base. Samples of less than 1 nanogram in microliter volumes can be conveniently handled.
    Type: Grant
    Filed: December 16, 1992
    Date of Patent: May 30, 1995
    Assignee: Hybridon, Inc.
    Inventors: Aharon S. Cohen, Maria Vilenchik
  • Patent number: 5122248
    Abstract: Apparatus and method for conducting electrophoresis in a capillary tube under the influence of a pulsed electric field. Apparatus for separating and detecting molecular species of a sample in a conductive medium includes a capillary tube for containing conductive medium, means for introducing a sample into a conductive medium-filled capillary tube, means for applying a pulsed electric field across the conductive medium-filled capillary tube between its ends, and means for detecting constituent molecular species of a sample in a conductive medium-filled capillary tube as they traverse the tube. A method for separating and detecting molecular species of a sample in a conductive medium includes the steps of introducing the sample into a capillary tube filled with conductive medium, applying a pulsed electric field of up to 500 volts/centimeter between the ends of the capillary, and detecting the constituent molecular species of the sample as they traverse the capillary.
    Type: Grant
    Filed: May 18, 1990
    Date of Patent: June 16, 1992
    Assignee: Northeastern University
    Inventors: Barry L. Karger, Aharon S. Cohen, David N. Heiger
  • Patent number: 5112460
    Abstract: A microcapillary column for high performance electrophoresis. A preferred column includes a microcapillary, a thin layer of coating material covalently bonded to the inner surface of the microcapillary wall, and a gel comprising polyacrylamide polymerized in the tube, filling it. The gel-containing microcapillary is prepared by covalently bonding a layer of a suitable coating material to the inner surface of the microcapillary wall, and then causing a mixture of monomer with or without crosslinking agent, initiator, and polymerization catalyst to react in the bore of the microcapillary to form a polymeric matrix.
    Type: Grant
    Filed: October 13, 1989
    Date of Patent: May 12, 1992
    Assignee: Northeastern University
    Inventors: Barry L. Karger, Aharon S. Cohen
  • Patent number: 4898658
    Abstract: An integrated temperature control/alignment system for use with a high performance capillary electrophoretic apparatus is disclosed. In one exemplary embodiment the integrated temperature control/alignment system comprises a pair of capillary column mounting plates for mounting a capillary column as a constituent of the electrophoretic apparatus, a pair of secondary support plates, a pair of thermoelectric plates and external heat sink plates. Detection openings are formed in each of the plates as required so that a continuous detection path exists through the integrated temperature control/alignment system. The capillary column is seated and locked in grooves formed in the capillary column mounting plates so that the detection windows of the capillary column are coordinated with the aligned detection openings formed in the applicable plates of the integrated temperature control/alignment system.
    Type: Grant
    Filed: November 25, 1987
    Date of Patent: February 6, 1990
    Assignee: Northeastern University
    Inventors: Barry L. Karger, Aran Paulus, Aharon S. Cohen, Robert J. Nelson
  • Patent number: 4865707
    Abstract: An improved microcapillary column for high performance electrophoresis includes a microcapillary, a hydrophilic polymer within a gel of crosslinked polyacrylamide polymerized in the tube, and preferably, a thin layer of connecting material covalently bonded to the inner surface of the microcapillary wall and to the polymeric gel. The microcapillary is prepared by first covalently bonding a suitable bifunctional reagent to the inner surface of the microcapillary wall, and then causing a mixture of the hydrophilic polymer, monomer, crosslinking agent, and polymerization catalyst to react in the bore of the microcapillary to form a hydrophilic polymer-containing gel matrix which is covalently bonded to the microcapillary wall via the bifunctional reagent.
    Type: Grant
    Filed: January 12, 1988
    Date of Patent: September 12, 1989
    Assignee: Northeastern University
    Inventors: Barry L. Karger, Aharon S. Cohen