Patents by Inventor Trinh Duc Nguyen

Trinh Duc Nguyen 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: 7439074
    Abstract: Method of identification and quantitative analysis of alcohol(s) in a sample by mass spectrometry using stable isotope labeled internal standard is provided. Said internal standard is prepared by reaction of an authentic sample of said alcohol with a stable isotope labeled reagent, and is added to a sample containing said alcohol. Said alcohol in said sample is then quantitatively converted to a chemical compound of identical structure, except the stable isotope atoms, as that of said internal standard using a non-labeled reagent. Said sample is then extracted and the extract is analyzed by mass spectrometry. Identification and quantification of said alcohol are made from a plot of ion ratio of said converted alcohol to said internal standard versus alcohol concentration.
    Type: Grant
    Filed: September 30, 2003
    Date of Patent: October 21, 2008
    Inventors: Hoa Duc Nguyen, Trinh Duc Nguyen, Duc Tien Nguyen
  • Patent number: 7309608
    Abstract: A method of identification and quantitative analysis of aldehydes and/or ketones in a sample by mass spectrometry using stable isotope labeled oxime internal standards or stable isotope labeled hydrazone internal standards is provided. Stable isotope labeled oxime internal standards are synthesized by reaction of an authentic sample of aldehydes and/or ketones with a stable isotope labeled alkoxylamine reagent while stable isotope labeled hydrazone internal standards are synthesized by reaction of an authentic sample of aldehydes and/or ketones with a stable isotope labeled alkylhydrazine reagent. A non labeled version of the stable isotope labeled reagent is used to convert aldehydes and/or ketones in the sample to the non labeled version of the stable isotope labeled oxime or hydrazone internal standards.
    Type: Grant
    Filed: September 30, 2003
    Date of Patent: December 18, 2007
    Inventors: Hoa Duc Nguyen, Trinh Duc Nguyen, Duc Tien Nguyen
  • Patent number: 5908927
    Abstract: A method of synthesizing deuterated morphine-3.beta.-glucuronide, morphine-6.beta.-glucuronide, and codeine-6.beta.-glucuronide is disclosed. The chemicals are used as internal standards for mass spectrometry analyses of morphine, heroin, and codeine uses. They are also useful in the study of metabolism of morphine and codeine.
    Type: Grant
    Filed: May 12, 1997
    Date of Patent: June 1, 1999
    Assignee: High Standard Products Corporation
    Inventors: Hoa Duc Nguyen, Duc Tien Nguyen, Raymond Albert Schep, Trinh Duc Nguyen, Phuong Thi Ngoc Pham