Patents by Inventor Pak-Ho Chan

Pak-Ho Chan 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).

  • Method and system for detection of chloramphenicol
    Patent number: 8329425
    Abstract: Fast and simple method of detecting the presence of chloramphenicol, a harmful compound if present in food products. The method makes use of a mutant chloramphenicol acetyltransferase (CAT) and a fluorophore-linked chloramphenicol in a system where chloramphenicol and the fluorophore-linked chloramphenicol competes for the active site of the mutant CAT. Because the fluorophore-linked chloramphenicol reduces its fluorescence upon binding to the active site and vice versa increases its fluorescence upon being displaced from the active site by the presence of unmodified chloramphenicol in a sample, the increase of fluorescence caused by a testing sample indicates the presence of chloramphenicol.
    Type: Grant
    Filed: February 28, 2011
    Date of Patent: December 11, 2012
    Assignee: The Hong Kong Polytechnic University
    Inventors: Kwok-Yin Wong, Yun Chung Leung, Pak Ho Chan, Wai Hong Chung, Ka Yan Chow, Ho yin Chow, Hon Man Leung
  • Method and System for Detection of Chloramphenicol
    Publication number: 20120219978
    Abstract: Fast and simple method of detecting the presence of chloramphenicol, a harmful compound if present in food products. The method makes use of a mutant chloramphenicol acetyltransferase (CAT) and a fluorophore-linked chloramphenicol in a system where chloramphenicol and the fluorophore-linked chloramphenicol competes for the active site of the mutant CAT. Because the fluorophore-linked chloramphenicol reduces its fluorescence upon binding to the active site and vice versa increases its fluorescence upon being displaced from the active site by the presence of unmodified chloramphenicol in a sample, the increase of fluorescence caused by a testing sample indicates the presence of chloramphenicol.
    Type: Application
    Filed: February 28, 2011
    Publication date: August 30, 2012
    Inventors: Kwok Yin Wong, Yun Chung Leung, Pak Ho Chan, Wai Hong Chung, Ka Yan Chow, Ho yin Chow, Ho Man Leung
  • Modified ?-lactamases and uses thereof
    Patent number: 7323303
    Abstract: A tool that can screen bacteria for ?-lactamases against a panel of various antibiotics is desirable. A biosensor incorporating an indicator molecule into ?-lactamases may achieve this purpose, but it requires that the attached indicator molecule must not impair the binding affinity of the protein to a great extent to provide a higher sensitivity. A modified ?-lactamases with a residue on the ?-loop or outside the ?-loop but close to the active site of ?-lactamase being replaced by a reactive residue is developed in this invention.
    Type: Grant
    Filed: March 31, 2003
    Date of Patent: January 29, 2008
    Assignee: Hong Kong Polytechnic University
    Inventors: Kwok-Yin Wong, Thomas Yun-Chung Leung, Pak-Ho Chan
  • Modified beta-lactamases and uses thereof
    Publication number: 20050261270
    Abstract: A tool that can screen bacteria for ?-lactamases against a panel of various antibiotics is desirable. A biosensor incorporating an indicator molecule into ?-lactamases may achieve this purpose, but it requires that the attached indicator molecule must not impair the binding affinity of the protein to a great extent to provide a higher sensitivity. A modified ?-lactamases with a residue on the ?-loop or outside the ?-loop but close to the active site of ?-lactamase being replaced by a reactive residue is developed in this invention.
    Type: Application
    Filed: March 31, 2003
    Publication date: November 24, 2005
    Applicant: The Hong Kong Polytechnic University
    Inventors: Kwok-Yin Wong, Thomas Leung, Pak-Ho Chan