Patents by Inventor Durgadas Bolikal

Durgadas Bolikal 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: 5622986
    Abstract: 2'- and/or 7'- substituted taxoid derivatives having improved water-solubility and/or enhanced therapeutic activity and methods of making the same are disclosed.
    Type: Grant
    Filed: December 12, 1994
    Date of Patent: April 22, 1997
    Assignee: Enzon, Inc.
    Inventors: Richard B. Greenwald, Durgadas Bolikal
  • Patent number: 5455027
    Abstract: Copolymers of poly(alkylene oxides) and amino acids or peptide sequences are disclosed, which amino acids or peptide sequences have pendant functional groups that are capable of being conjugated with pharmaceutically active compounds for drug delivery systems and cross-linked to form polymer matrices functional as hydrogel membranes. The copolymers can also be formed into conductive materials. Methods are also disclosed for preparing the polymers and forming the drug conjugates, hydrogel membranes and conductive materials.
    Type: Grant
    Filed: February 25, 1993
    Date of Patent: October 3, 1995
    Assignee: Enzon, Inc.
    Inventors: Samuel Zalipsky, Durgadas Bolikal, Aruna Nathan, Joachim B. Kohn
  • Patent number: 5219564
    Abstract: Copolymers of poly(alkylene oxides) and amino acids or peptide sequences are disclosed, which amino acids or peptide sequences have pendant functional groups that are capable of being conjugated with pharmaceutically active compounds for drug delivery systems and cross-linked to form polymer matrices functional as hydrogel membranes. The copolymers can also be formed into conductive materials. Methods are also disclosed for preparing the polymers and forming the drug conjugates, hydrogel membranes and conductive materials.
    Type: Grant
    Filed: July 5, 1991
    Date of Patent: June 15, 1993
    Assignee: Enzon, Inc.
    Inventors: Samuel Zalipsky, Durgadas Bolikal, Aruna Nathan, Joachim B. Kohn
  • Patent number: 5160600
    Abstract: The process of electroless plating of polymers containing units derived from at least one member of the group consisting of acrylonitrile, butadiene and styrene, is carried out in an environment free of chromium ions, by the sequential steps of roughening and activating the surface of the polymer by contacting the same with an aqueous solution of a concentrated sulfur acid, of concentrated nitric acid or of concentrated phosphoric acid, in the presence of noble metal ion and an oxidant selected from the group consisting of nitric acid, hydrogen peroxide and persulfates. This is followed by an aqueous suspension of Pd.sup.0 and then by the conventional chemical metallization.
    Type: Grant
    Filed: March 5, 1990
    Date of Patent: November 3, 1992
    Inventors: Gordhanbai N. Patel, Durgadas Bolikal, Hemant H. Patel
  • Patent number: 5049230
    Abstract: A one-step process for treating polymer surfaces prior to electroless deposition is disclosed. Polymer parts are dipped in a solution containing a good solvent for the polymer, a substantial non-solvent for the polymer, an etchant and, where one of these is immiscible with one or more of the others, a solubilizing agent miscible with the immiscible components to provide a single liquid phase. Formulations are provided for pre-swelling and etching of functionalized polymers, such as polycarbonate in one, two and three steps. The etched surface can then be plated with electroless nickel or copper with satisfactory adhesion of the plated metals. Swelling agents make polymer molecules on and near the surface of the polymer easily accessible to a degradation agent. A degradation agent degradates the polymer molecules. If required, a solubilizing agent increases the miscibility of the degradation agent and the swelling agent. A wetting agent increases the effectiveness of the etching agent.
    Type: Grant
    Filed: March 6, 1990
    Date of Patent: September 17, 1991
    Assignee: JP Laboratories, Inc.
    Inventors: Gordhanbhai N. Patel, Durgadas Bolikal
  • Patent number: 5015329
    Abstract: Formulations are provided for pre-swelling and etching of functionalized polymers, such as polycarbonate in two or three steps. The etched surface can then be plated with electroless nickel or copper with satisfactory adhesion of the plated metals. Swelling agents make polymer molecules on and near the surface of the polymer easily accessible to a degradation agent. A degradation agent degradates the polymer molecules. If required, a solubilizing agent increases the miscibility of the degradation agent and the swelling agent. A wetting agent increases the effectiveness of the etching agent. In a two-step process, polymer parts are first treated with a solution of a swelling agent followed by etching with a solution of degradation agent.
    Type: Grant
    Filed: March 6, 1990
    Date of Patent: May 14, 1991
    Assignee: JP Laboratories, Inc.
    Inventors: Gordhanbhai N. Patel, Durgadas Bolikal, Richard A. Bellemare
  • Patent number: 4941940
    Abstract: Formulations are provided for pre-swelling and etching of functionalized polymers, such as polycarbonate in one, two and three steps. The etched surface can then be plated with electroless nickel or copper with satisfactory adhesion of the plated metals. Swelling agents make polymer molecules on and near the surface of the polymer easily accessible to a degradation agent. A degradation agent degradates the polymer molecules. If required, a solubilizing agent increases the miscibility of the degradation agent and the swelling agent. A wetting agent increases the effectiveness of the etching agent.In the one-step process, polymer parts are dipped in a solution containing at least one swelling agent and at least one degradation agent. In the two-step process, polymer parts are first treated with a solution of a swelling agent followed by etching with a solution of degradation agent.
    Type: Grant
    Filed: November 7, 1988
    Date of Patent: July 17, 1990
    Assignee: JP Laboratories, Inc.
    Inventors: Gordhanbhai N. Patel, Durgadas Bolikal, Richard A. Bellemare