Thomas P Doherty

US Patent:

6610978, Aug 26, 2003

Filed:

Mar 27, 2001

Appl. No.:

09/820321

Inventors:

Hongfeng Yin - San Jose CA
Thomas P. Doherty - San Mateo CA
Sally A Swedberg - Palo Alto CA

Assignee:

Agilent Technologies, Inc. - Palo Alto CA

International Classification:

H01J 4900

US Classification:

250288, 422 681, 250281, 250252

Abstract:

The present invention relates to microdevices for introducing a small volume of a fluid sample into an ionization chamber. The microdevices are constructed from a substrate having a first and second opposing surfaces, the substrate having a microchannel formed in the first surface, and a cover plate arranged over the first surface, the cover plate in combination with the microchannel defining a conduit for conveying the sample. A sample inlet port is provided in fluid communication with the microchannel, wherein the sample inlet port allows the fluid sample from an external source to be conveyed in a defined sample flow path that travels, in order, through the sample inlet port, the conduit and a sample outlet port and into the ionization chamber. Optionally, the fluid sample undergoes a chemical or biochemical reaction within an integrated portion of the microdevice before reaching the ionization chamber. A nebulizing means nebulizes the fluid sample in a nebulizing region adjacent to the sample outlet port.

US Patent:

6649908, Nov 18, 2003

Filed:

Sep 20, 2001

Appl. No.:

09/960890

Inventors:

Hongfeng Yin - San Jose CA
Thomas P. Doherty - San Mateo CA

Assignee:

Agilent Technologies, Inc. - Palo Alto CA

International Classification:

H01J 4904

US Classification:

250288

Abstract:

A transfer capillary and interface are provided that allow samples from multiple fluid streams to be introduced into a single mass analyzer. The transfer capillary has two or more channels and is placed between a first chamber, in which ions from the multiple fluid streams are generated, and a second chamber that is in fluid communication with a mass analyzer. The interface includes ionizers that generate ionized sample from each fluid stream and that direct the ionized sample toward the channels of the transfer capillary. The transfer capillary includes a multiplex selector that allows ions to flow through a selected subset of channels and sequentially changes which of the channels are included in the subset of channels through which ions flow.

US Patent:

6723516, Apr 20, 2004

Filed:

Oct 24, 1996

Appl. No.:

08/738464

Inventors:

Thomas P. Doherty - San Mateo CA
Richard L. Baer - Los Altos CA

Assignee:

Agilent Technologies, Inc. - Palo Alto CA

International Classification:

G01N 3353

US Classification:

435 71, 435 6, 435 75, 435969, 422 8201, 422 98, 436517, 436518, 436161

Abstract:

A method is provided for continuously monitoring for the presence or quantity of an analyte in a flowing liquid stream. The method involves binding an analyte-specific receptor species to the surface of a piezoelectric substrate, contacting the surface bound receptor species with the flowing liquid stream and quantitating the presence of the analyte. A novel apparatus for detecting the presence of an analyte in a liquid chromatography eluant is provided as well.

US Patent:

20050095599, May 5, 2005

Filed:

Oct 30, 2003

Appl. No.:

10/699478

Inventors:

Richard Pittaro - San Carlos CA, US
Edward Verdonk - San Jose CA, US
Thomas Doherty - San Mateo CA, US

International Classification:

C12Q001/68
G01N033/53
C12M001/34

US Classification:

435006000, 435007100, 435287200

Abstract:

The present invention provides an apparatus for detecting a nanoscale moiety and a method for sensing a nanoscale moiety. The apparatus includes a substrate having a nanopore, at least one excitable molecule attached to the substrate adjacent to the nanopore, and a light source for exciting the excitable molecule attached to the substrate adjacent to the nanopore wherein the excitable molecule is quenched by the quencher molecule on the nanoscale moiety as it passes by the excitable molecule. The invention also includes a method for detecting the presence or identity of the nanoscale moiety.

US Patent:

20090134324, May 28, 2009

Filed:

Feb 3, 2009

Appl. No.:

12/364527

Inventors:

Douglas J. King - Union City CA, US
Thomas Patrick Doherty - San Mateo CA, US
Jeffrey Thomas Kernan - Santa Cruz CA, US

Assignee:

AGILENT TECHNOLOGIES, INC. - Loveland CO

International Classification:

B01D 59/44
H01J 49/00

US Classification:

250282, 250281

Abstract:

A mass spectrometry system comprises a panel movable between an open and closed position relative to a housing. At least part of ion-optics is mounted to the panel. The housing surrounds ion-optics and a partition forms a gas barrier separating vacuum-chambers within the housing when the panel is in the closed position. The gas barrier formed by the partition is broken when the panel moves to the open position.

US Patent:

20090194679, Aug 6, 2009

Filed:

Jan 31, 2008

Appl. No.:

12/023385

Inventors:

Thomas P. Doherty - San Mateo CA, US
Jeffrey T. Kernan - Santa Cruz CA, US
James D. Foote - Sunnyvale CA, US

Assignee:

Agilent Technologies, Inc. - Palo Alto CA

International Classification:

H01J 49/26

US Classification:

250282, 250288

Abstract:

The invention pertains to methods and apparatus for performing mass spectrometry with reduced noise. In some embodiments, an additional amount of a carrier gas is introduced into a mass spectrometer to reduce the noise.

US Patent:

62221868, Apr 24, 2001

Filed:

Jun 25, 1998

Appl. No.:

9/104754

Inventors:

Gangqiang Li - Palo Alto CA
Thomas P. Doherty - San Mateo CA
Carl A. Myerholtz - Cupertino CA

Assignee:

Agilent Technologies, Inc. - Palo Alto CA

International Classification:

H01J 4900
B01D 5944

US Classification:

250288

Abstract:

A technique that modulates the power of a inductively coupled plasma (ICP) according to the operative modes of a spectrometer. An analytical apparatus of the present invention contains an inductively coupled plasma generator (ICPG) and a spectrometer. The ICPG generates a plasma for forming ionic and excited molecular species from a sample. The spectrometer analyzes the ionic and excited molecular species formed. The spectrometer operates in an analysis mode wherein the ionic and excited molecular species are identified according to physical characteristics of the species to provide data on the species and further has a washout mode wherein the spectrometer flushes out interfering ions and molecules and provides no significant data on the sample. The controller modulates the ICPG to operate in power cycles, at each cycle the ICPG operates in an analysis period and a stand-by period. By modulating the plasma power, the power consumption and heat dissipation can be reduced.

US Patent:

53066448, Apr 26, 1994

Filed:

Apr 1, 1993

Appl. No.:

8/041662

Inventors:

Carl A. Myerholtz - Cupertino CA
Richard L. Baer - Los Altos CA
Thomas P. Doherty - San Mateo CA

Assignee:

Hewlett-Packard Company - Palo Alto CA

International Classification:

G01N 2700
G01N 3300
H01L 4100
H01L 4108

US Classification:

436149

Abstract:

A system for accurate and precise measurements of analyte(s) in a system. The measurement system comprises piezoelectric surface wave sample devices, at least one piezoelectric surface wave reference device, and the measurement instrument.