Patents by Inventor James A. Apffel

James A. Apffel 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: 5716825
    Abstract: An integrated nucleic acid sample analysis system for matrix-assisted laser-desorption/ionization time-of-flight mass spectroscopy (MALDI-TOF MS) is described. The integrated system comprises a miniaturized sample preparation compartment interfaced directly with a MALDI-TOF ionization surface for amplifying and/or otherwise chemically manipulating an oligonucleotide analyte and presenting the analyte to a MALDI ionization surface for mass spectrometry analysis. The miniaturized integrated sample handling system disclosed herein finds application in the amplification and analysis of DNA samples for genetic diagnosis and other uses.
    Type: Grant
    Filed: November 1, 1995
    Date of Patent: February 10, 1998
    Assignee: Hewlett Packard Company
    Inventors: William S. Hancock, John A. Chakel, James A. Apffel, Kay Lichtenwalter
  • Patent number: 5705813
    Abstract: An integrated liquid sample handling system for matrix-assisted laser-desorption/ionization time-of-flight mass spectroscopy (MALDI-TF MS) is described. The integrated system comprises a miniaturized sample handling compartment containing a MALDI ionization surface for separating, chemically manipulating and detecting analytes by MALDI -TOF MS. The miniaturized integrated sample handling system disclosed herein is applicable to a wide range of analytical problems that require separation and/or chemical manipulation of a sample prior to mass analysis as part of the analytical procedure.
    Type: Grant
    Filed: November 1, 1995
    Date of Patent: January 6, 1998
    Assignee: Hewlett-Packard Company
    Inventors: James A. Apffel, John A. Chakel, William S. Hancock, Kay Lichtenwalter
  • Patent number: 5495108
    Abstract: The invention teaches the uses of a plurality of electric fields and of orthogonal spray configurations of vaporized analyte which combine so as to operate to enhance the efficiency of analyte detection and mass analysis with a mass spectrometer by reducing vapor in the vacuum system and concomitant noise. Several embodiments of the invention are described for purposes of illustration.
    Type: Grant
    Filed: July 11, 1994
    Date of Patent: February 27, 1996
    Assignee: Hewlett-Packard Company
    Inventors: James A. Apffel, Jr., Mark H. Werlich, James L. Bertsch
  • Patent number: 5447553
    Abstract: Close coupled momentum separator with integral removable source volume for particle beam liquid chromatography/mass spectrometry is provided. The inventive PB LC/MS system comprises a momentum separator wherein the skimmers are designed to accommodate the particle beam conical dispersion so as to minimize the number of particles lost in the separator. In addition, the exit of the momentum separator is closely coupled to the entrance of the MS source volume. The PB LC/MS system demonstrates improved linearity in signal and enhanced sensitivity.
    Type: Grant
    Filed: October 19, 1994
    Date of Patent: September 5, 1995
    Assignee: Hewlett-Packard Company
    Inventors: James A. Apffel, Jr., Robert G. Nordman, Mirko Martich
  • Patent number: 5331159
    Abstract: A liquid chromatography-mass spectrometry system that can be configured as either a particle beam or an electrospray interface is provided. The device incorporates structural elements that are common to both interfaces thereby eliminating the need to have two completely separate ES and PB LC/MS systems. The LC/MS device according to the present invention generally comprises a momentum separator, nozzle housing, mass spectrometer, and a vacuum subsystem. A mass spectrometer housing encloses a quadrupole mass analyzer. When used in the ES mode, and ES source module is coupled into the inventive device. Similarly, when used in the PB mode, a PB source module is coupled into the inventive device along with a separate source PB probe. The mass analyzer chamber can accommodate a particle beam source probe for generating ions from analyte particles. In either mode, the modules can consist of commercially available interfaces modified for use with the inventive device.
    Type: Grant
    Filed: January 22, 1993
    Date of Patent: July 19, 1994
    Assignee: Hewlett Packard Company
    Inventors: James A. Apffel, Jr., Robert G. Nordman
  • Patent number: 5223131
    Abstract: Close coupled momentum separator with integral removable source volume for particle beam liquid chromatography/mass spectrometry is provided. The inventive PB LC/MS system comprises a momentum separator wherein the skimmers are designed to accommodate the particle beam conical dispersion so as to minimize the number of particles lost in the separator. In addition, the exit of the momentum separator is closely coupled to the entrance of the MS source volume. The PB LC/MS system demonstrates improved linearity in signal and enhanced sensitivity.
    Type: Grant
    Filed: October 8, 1991
    Date of Patent: June 29, 1993
    Assignee: Hewlett-Packard Company
    Inventors: James A. Apffel, Jr., Robert G. Nordman, Mirko Martich
  • Patent number: 4784962
    Abstract: A mixture of fluorescently-excitable amino acid derivatives suitable for use in quantitative amino acid analysis is provided in which primary amino acids are present as derivatives of a first reagent and secondary amino acids are present as derivatives of a second different reagent. The process for preparing the mixture comprises the steps of derivatization of the primary amino acids of an amino acid sample with ortho-phthalaldehyde (OPA) and of derivatization of the secondary amino acids of the sample with fluorenylmethylchloroformate (FMOC) in the presence of acetonitrile. The mixture can be obtained automatically and is highly suitable for fast analysis by reversed-phase liquid chromatography.
    Type: Grant
    Filed: February 25, 1987
    Date of Patent: November 15, 1988
    Assignee: Hewlett-Packard Company
    Inventors: James A. Apffel, Jr., Rainer Schuster