Patents by Inventor Parameswara Reddy

Parameswara Reddy 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: 6465692
    Abstract: Formamide with low conductivity and a neutral or slightly basic pH is provided. Such formamide may be used in a sample loading solution for capillary electrophoretic separation of biomolecular analytes to enhance the efficiency of sample injection into the capillary and the intensity of the signal. Formamide of the present invention may be obtained by first purifying the formamide to a conductivity of below 7 micro mho, and then adjusting the pH of the purified formamide with a base to a range of about pH 6.5 to 7.5. The purification may be carried out by first removing the water from the formamide, and then distilling the dried formamide until the conductivity of formamide is below about 7 micro mho.
    Type: Grant
    Filed: December 22, 1999
    Date of Patent: October 15, 2002
    Assignee: Beckman Coulter, Inc.
    Inventors: M. Parameswara Reddy, Chitra K. Ratnayake, Yu Liu, Jirong Gu
  • Patent number: 6375818
    Abstract: An article of manufacture is provided that is useful in differentiating between solutes, such as during electrophoretic separations. An embodiment of the article is a capillary tube, that carries a polymer along the inner wall of the capillary tube. The polymer is effective to reduce undesired interactions and preferably includes a polylactam that is absorbed to the surface before the surface is exposed to the solutes. A preferred polylactam is poly(vinylpyrrolidone) with a molecular weight greater than about 1,000,000 daltons (weight-average).
    Type: Grant
    Filed: June 8, 1999
    Date of Patent: April 23, 2002
    Assignee: Beckman Coulter, Inc.
    Inventors: Tung-Liang Huang, M. Parameswara Reddy
  • Patent number: 6335450
    Abstract: This invention provides cyclic-bridged dyes, particularly cyclic-bridged cyanine dyes, of the general formula: In this formula, each dotted line represents carbon atoms necessary to form a fused substituted or unsubstituted aromatic ring; n=1-18; m=1-18, selected independently from n. X and Y are selected independently from the group consisting of S, O, N, CH2 and C(CH3)2; at least one of said R1 and R2 comprises a sulfonic acid or sulfonate group attached to the aromatic ring; and R3 and R4 are independently selected from the group consisting of carboxyl, activated carboxyl and methyl, wherein at least one of said R3 and R4 groups is carboxylate or activated carboxylate. Methods of making and using the cyclic-bridged dyes are also provided.
    Type: Grant
    Filed: November 9, 2000
    Date of Patent: January 1, 2002
    Assignee: Beckman Coulter, Inc.
    Inventors: Firdous Farooqui, Maged A. Michael, M. Parameswara Reddy
  • Patent number: 6294064
    Abstract: Reagents and methods for preparing samples containing both biomolecule analytes and macrobiomolecules for capillary electrophoresis separation are provided. The reagents comprise a branched polymer. When mixed with a sample containing both biomolecule analytes and macrobiomolecules, particularly DNA templates, the branched polymer of the reagent can suppress the entrance of the macrobiomolecules into a capillary electrophoresis tube during electrokinetic injection of the sample into the capillary electrophoresis tube.
    Type: Grant
    Filed: November 23, 1999
    Date of Patent: September 25, 2001
    Assignee: Beckman Coulter, Inc.
    Inventors: M. Parameswara Reddy, Tung-Liang Huang, Chitra K. Ratnayake, Daniel A. Keys
  • Patent number: 6110630
    Abstract: Activating groups based on N-hydroxynaphthalimide, are disclosed herein. The activating groups can mediate the coupling of labeling moieties, such as biotin or cyanine dyes, to a variety of components, including chain terminators, nucleoside triphosphates, and oligonucleotides, which are used in nucleotide sequencing. From these activating groups, activated esters of the labeling moieties can be prepared. The activated esters react with a component, for example a derivatized nucleotide chain terminator, to give a labeled component. In additions, methods of the present invention provide for labeling a nucleoside triphosphate in organic media. The activating groups and methods of the present invention allow the activation and coupling reactions to occur at a much higher yield, compared with the prior art.
    Type: Grant
    Filed: June 18, 1998
    Date of Patent: August 29, 2000
    Assignee: Beckman Coulter, Inc.
    Inventors: M. Parameswara Reddy, Maged A. Michael, Firdous Farooqui, Naeem B. Hanna
  • Patent number: 5869696
    Abstract: Universal solid support oligonucleotide synthesis reagents, oligonucleotide synthesis processes, and reagents for cleaving oligonucleotides from solid supports are disclosed. Oligonucleotide synthesis reagents have the following general formula:SS--R.sup.6 --O--R.sup.3 Iwherein SS is a solid support; R.sup.6 is ##STR1## where R.sup.5 is hydrogen or alkyl and R.sup.4 is a phosphate protecting group; and R.sup.3 is a ring moiety having vicinal groups --XR.sup.1 and --YR.sup.2 wherein each of X and Y is independently selected from the group consisting of O, S and NH and one of R.sup.1 and R.sup.2 is a blocking moiety and the other is hydrogen or a hydroxy protecting group. Oligonucleotide cleaving reagents include methylamine and/or ammonium hydroxide and trimethylamine.
    Type: Grant
    Filed: April 22, 1996
    Date of Patent: February 9, 1999
    Assignee: Beckman Instruments, Inc.
    Inventors: M. Parameswara Reddy, Maged A. Michael, Firdous Farooqui
  • Patent number: 5808039
    Abstract: A compound of the general formula ##STR1## wherein R is alkyl of 1 to about 10 carbons and R' is selected from the group consisting of trityl and pixyl, for use in the synthesis of 2'-OMe RNA sequences. Fast cleavage and deprotection of oligonucleotides is facilitated by the use of a reagent comprising methylamine as active component in place of the traditional reagent ammonium hydroxide.
    Type: Grant
    Filed: October 18, 1995
    Date of Patent: September 15, 1998
    Assignee: Beckman Instruments, Inc.
    Inventors: Meda Parameswara Reddy, Firdous Farooqui, Naeem B. Hanna
  • Patent number: 5783684
    Abstract: Oxidizing compositions particularly for use in automated oligonucleotide synthesis containing a mixture of KI and I.sub.2 in solution, in equilibrium with KI.sub.3. One preferred composition contains 1.75% KI.sub.3 (providing 0.69% KI and 1.06% I.sub.2) in tetrahydrofuran/pyridine/water (93/5/2, v/v). These formulations enable synthesis of oligonucleotides of significantly higher quality than the currently employed formulation comprising 3% I.sub.2 in tetrahydrofuran/pyridine/water (74/21/2, v/v).
    Type: Grant
    Filed: September 11, 1995
    Date of Patent: July 21, 1998
    Assignee: Beckman Instruments, Inc.
    Inventors: Meda Parameswara Reddy, Firdous Farooqui, Maged A. Michael
  • Patent number: 5731429
    Abstract: A compound of general formula ##STR1## wherein R is methyl R' is selected from the group consisting of trityl and pixyl, and R" is H or OMe. These compounds may advantageously be employed in the synthesis of oligonucleotides by conventional methods, such as automated solid phase synthesis. Use of ethylene diamine in the cleavage and deprotection procedure substantially eliminates the formation of undesirable side products.
    Type: Grant
    Filed: October 18, 1995
    Date of Patent: March 24, 1998
    Assignee: Beckman Instruments, Inc.
    Inventors: Meda Parameswara Reddy, Firdous Farooqui, Naeem B. Hanna
  • Patent number: 5726301
    Abstract: Disclosed herein are N.sup.4 protected deoxycytidines for use in the synthesis of oligonucleotides, the protecting groups being represented by the formula: --CO--(CH.sub.2).sub.0-9 --CH.sub.3. Preferred embodiments are N.sup.4 acetyl deoxycytidines and include N.sup.4 acetyl deoxycytidine phosphoramidites and N.sup.4 acetyl deoxycytidine H-phosphonates. When used to prepare oligonucleotides the protected deoxycytidine compounds provide high quality oligonucleotide products with little side product from cleavage and deprotection reactions carried out with alkyl amine compounds.
    Type: Grant
    Filed: March 31, 1995
    Date of Patent: March 10, 1998
    Assignee: Beckman Instruments, Inc.
    Inventors: M. Parameswara Reddy, Naeem B. Hanna, Firdous Farooqui
  • Patent number: 5648213
    Abstract: Double stranded nucleic acid duplexes serve as universal harvestable and cleavable link systems in a variety of different types of immunoassays (e.g., sandwich, competitive, etc.). Depending upon the type of assay, at least one specific component involved in the assay system is attached to a first member of a pair of sequences forming a double stranded nucleic acid (i.e., two oligonucleotides comprising substantially complementary sequences). The assay is carried out in the presence of a support to which is attached an oligonucleotide which is the other member of the pair of sequences forming a double-stranded nucleic acid duplex under hybridization conditions. Upon the hybridization of the two complementary oligonucleotides to form a duplex, the component of the assay system to which the first member of the pair of oligonucleotides is attached may thereby be effectively removed from the solution phase and harvested onto the support.
    Type: Grant
    Filed: August 30, 1994
    Date of Patent: July 15, 1997
    Assignee: Beckman Instruments, Inc.
    Inventors: M. Parameswara Reddy, James C. Sternberg
  • Patent number: 5623068
    Abstract: Deoxyribonucleotide and ribonucleotide derivatives of the general formula I ##STR1## wherein R.sup.1 represents --CR'R"--Ar, in which Ar is substituted aryl (as hereinafter defined) and R' and R" are independently selected from the group consisting of hydrogen and lower alkyl; one of --R.sup.2 and R.sup.3 is a hydroxyl-protecting group and the other is a group suitable for synthesis of polynucleotides or for attachment of the nucleotide to a solid support; R.sup.4 is selected from the group consisting of hydrogen, --OH and protected hydroxyl; and B represents a divalent radical corresponding to a purine or pyrimidine base. When synthesis is carried out using these derivatives, the deprotection procedure is reduced to an essentially instantaneous process. The derivatives have acceptable shelf life and are very stable to conventional DNA synthesis conditions. Particularly preferred are those compounds wherein Ar is mono- and dihalo-substituted phenyl.
    Type: Grant
    Filed: March 1, 1995
    Date of Patent: April 22, 1997
    Assignee: Beckman Instruments, Inc.
    Inventors: M. Parameswara Reddy, Firdous Farooqui, Naeem B. Hanna
  • Patent number: 5616700
    Abstract: Disclosed herein are protecting groups for exocyclic amino groups of the base cytosine for use in the synthesis of oligonucleotides and oligonucleoside phosphorothioates, the protecting groups being represented by the formula: --CO--(CH.sub.2).sub.0-9 --CH.sub.3. In a particularly preferred embodiment, the base cytosine is protected with acetyl (--CO--CH.sub.3), and the oligonucleotide or oligonucleoside phosphorothioate incorporating the protected cytosine is subjected to a cleavage/deprotection reagent comprising methylamine and ammonia.
    Type: Grant
    Filed: November 18, 1993
    Date of Patent: April 1, 1997
    Assignee: Beckman Instruments, Inc.
    Inventors: M. Parameswara Reddy, Firdous Farooqui
  • Patent number: 5574146
    Abstract: A process for synthesizing oligonucleotides by phosphoramidite chemistry wherein the improvement is the use of substituted aryl carboxylic acids as the activators. These activators produce in situ nucleotide intermediates in which the substituted arylcarbonyl group has displaced the amidite moiety.
    Type: Grant
    Filed: August 30, 1994
    Date of Patent: November 12, 1996
    Assignee: Beckman Instruments, Inc.
    Inventors: M. Parameswara Reddy, Firdous Farooqui