Patents by Inventor Xuan S. Zhao

Xuan S. Zhao 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).

  • Multi-arm polypeptide-poly(ethylene glycol) block copolymers as drug delivery vehicles
    Patent number: 7976834
    Abstract: The invention provides a multi-arm block copolymer for use in delivering a variety of bioactive agents. The copolymer of the invention contains a central core from which extend multiple (3 or more) copolymer arms. Each copolymer arm possesses an inner polypeptide segment and an outer hydrophilic polymer segment. Thus, the overall structure of the copolymer comprises an inner core region that includes the central core and the inner polypeptide segment, while the outer core region is hydrophilic in nature. The multi-arm copolymer of the invention is particularly useful for delivery of biologically active agents that can be entrapped within the inner core region.
    Type: Grant
    Filed: November 14, 2007
    Date of Patent: July 12, 2011
    Assignee: Nektar Therapeutics
    Inventors: Xuan S. Zhao, Zhongxu Ren, Kazunori Emoto
  • Multi-arm polypeptide-poly (ethylene glycol) block copolymers as drug delivery vehicles
    Publication number: 20040161403
    Abstract: The invention provides a multi-arm block copolymer for use in delivering a variety of bioactive agents. The copolymer of the invention contains a central core from which extend multiple (3 or more) copolymer arms. Each copolymer arm possesses an inner polypeptide segment and an outer hydrophilic polymer segment. Thus, the overall structure of the copolymer comprises an inner core region that includes the central core and the inner polypeptide segment, while the outer core region is hydrophilic in nature. The multi-arm copolymer of the invention is particularly useful for delivery of biologically active agents that can be entrapped within the inner core region.
    Type: Application
    Filed: December 24, 2003
    Publication date: August 19, 2004
    Inventors: Xuan S. Zhao, Zhongxu Ren, Kazunori Emoto