Alan G Marshall

US Patent:

7078684, Jul 18, 2006

Filed:

Feb 4, 2005

Appl. No.:

11/051092

Inventors:

Steven C. Beu - Austin TX, US
Greg T. Blakney - Tallahassee FL, US
John P. Quinn - Havana FL, US
Christopher L. Hendrickson - Tallahassee FL, US
Alan G. Marshall - Tallahassee FL, US

Assignee:

Florida State University - Tallahasee FL

International Classification:

H01J 49/34
H01J 49/26

US Classification:

250291, 250292, 250282, 250288, 250281

Abstract:

A high resolution Fourier Transform Ion Cyclotron Resonance (FT-ICR) mass spectrometry system includes excitation circuitry including an excitation amplifier for generating an electrical excitation signal and excitation electrodes for applying an oscillating electric field to excite ions in the system. Detection circuitry including detection electrodes measures a detection signal which includes a plurality of signal values including signal values induced by the ions. Structure is provided for reducing or canceling coupling of the excitation signal into the detection signal, wherein simultaneous excitation and detection is used. A computing structure generates a Fourier transformed frequency domain representation of the detection signal and deconvolves the frequency domain representation using complex division to separate a dispersion spectrum portion and an absorption spectrum portion.

US Patent:

7601542, Oct 13, 2009

Filed:

Feb 8, 2007

Appl. No.:

11/672789

Inventors:

Mark R. Emmett - Monticello FL, US
Sasa Kazazic - Tallahassee FL, US
Alan G. Marshall - Tallahassee FL, US
Michael J. Greig - Carlsbad CA, US

Assignee:

Florida State University Research Foundation - Tallahassee FL

International Classification:

G01N 33/00

US Classification:

436 86, 436161, 435 71, 435 23, 210634, 210136, 210656, 73 6156, 422 69, 422103

Abstract:

Analytical methods using hydrogen/deuterium exchange are provided which reduce or eliminate the back-exchange of deuterium for hydrogen. The methods, which are useful in protein and peptide mapping, include the steps of (a) providing a peptide or protein comprising a solvent accessible hydrogen; (b) exchanging the solvent accessible hydrogen for a deuterium; (c) separating the peptide or protein with supercritical fluid chromatography; and (d) analyzing by mass spectrometry the mass of the separated peptide or protein. Supercritical fluid chromatography enables the observation of fast exchanging hydrogen atoms missed using conventional liquid chromatography methods.

US Patent:

7960179, Jun 14, 2011

Filed:

Oct 12, 2009

Appl. No.:

12/577452

Inventors:

Mark R. Emmett - Monticello FL, US
Sasa Kazazic - Zagreb, HR
Alan G. Marshall - Tallahassee FL, US
Michael J. Greig - Carlsbad CA, US

Assignee:

Florida State University Research Foundation - Tallahassee FL

International Classification:

G01N 33/00

US Classification:

436 86, 436161, 435 71, 435 23, 210634, 210136, 210656, 73 6156, 422 69

Abstract:

Analytical methods using hydrogen/deuterium exchange are provided which reduce or eliminate the back-exchange of deuterium for hydrogen. The methods, which are useful in protein and peptide mapping, include the steps of (a) providing a peptide or protein comprising a solvent accessible hydrogen; (b) exchanging the solvent accessible hydrogen for a deuterium; (c) separating the peptide or protein with supercritical fluid chromatography; and (d) analyzing by mass spectrometry the mass of the separated peptide or protein. Supercritical fluid chromatography enables the observation of fast exchanging hydrogen atoms missed using conventional liquid chromatography methods.

US Patent:

8084264, Dec 27, 2011

Filed:

Jan 27, 2010

Appl. No.:

12/694606

Inventors:

Alan G. Marshall - Tallahassee FL, US
Priyanka Juyal - Tallahassee FL, US
Mmilili M. Mapolelo - Tallahassee FL, US
Ryan P. Rodgers - Tallahassee FL, US

Assignee:

Florida State University Research Foundation, Inc. - Tallahassee FL

International Classification:

G01N 33/26
G01N 31/02
G01N 30/72

US Classification:

436129, 436 60, 436127, 436139, 436173, 436174

Abstract:

A method for quantifying the presence of naphthenic acids in a hydrocarbon-comprising liquid that includes: contacting a hydrocarbon-comprising liquid with gaseous ammonia; isolating a reaction product produced by the contacting step; and analyzing the reaction product for the presence of naphthenates using a mass spectrometry technique. The naphthenic acids known to form commercial naphthenate deposits can be (i) ions of tetraprotic carboxylic acids having molecular weights ranging from 1225 to 1270 Daltons, (ii) n-alkyl or branched carboxylic acids having molecular weights ranging from 250 to 650 Daltons, or (iii) both.

US Patent:

8110797, Feb 7, 2012

Filed:

Feb 5, 2010

Appl. No.:

12/700992

Inventors:

Alan G. Marshall - Tallahassee FL, US
Priyanka Juyal - Tallahassee FL, US
Ryan P. Rodgers - Tallahassee FL, US

Assignee:

Florida State University Research Foundation, Inc. - West Palm Beach FL

International Classification:

B01D 59/44
H01J 49/26

US Classification:

250288, 250423 R, 250424, 250425

Abstract:

A method of enhanced speciation of both positive and negatives species in an analyte is disclosed. The method can include producing a first analyte solution comprising an analyte composition and an effective amount of silver triflate, and analyzing the first analyte solution with an electrospray ionization mass spectrometer. The method can also include producing a second analyte solution comprising a portion of the analyte composition and an effective amount of a compound of formula I, and analyzing the second analyte solution with an electrospray ionization mass spectrometer. The compound of formula I is [NX][OH], where X is a linear, branched, or cyclic C-Calkane; an aryl; a heterocyclic aromatic; or a heterocyclic moiety.

US Patent:

8530834, Sep 10, 2013

Filed:

Feb 6, 2012

Appl. No.:

13/366824

Inventors:

Alan G. Marshall - Tallahassee FL, US
Priyanka Juyal - Tallahassee FL, US
Ryan P Rodgers - Tallahassee FL, US

Assignee:

Florida State University Research Foundation, Inc. - Tallahassee FL

International Classification:

B01D 59/44
H01J 49/26
H01J 49/00

US Classification:

250288, 250423 R, 250424, 250425

Abstract:

A method of enhanced speciation of both positive and negatives species in an analyte is disclosed. The method can include producing a first analyte solution comprising an analyte composition and an effective amount of silver triflate, and analyzing the first analyte solution with an electrospray ionization mass spectrometer. The method can also include producing a second analyte solution comprising a portion of the analyte composition and an effective amount of a compound of formula I, and analyzing the second analyte solution with an electrospray ionization mass spectrometer. The compound of formula I is [NX][OH], where X is a linear, branched, or cyclic C-Calkane; an aryl; a heterocyclic aromatic; or a heterocyclic moiety.

US Patent:

20100159501, Jun 24, 2010

Filed:

Dec 23, 2009

Appl. No.:

12/646352

Inventors:

Mark R. Emmett - Monticello FL, US
Huan He - Tallahassee FL, US
Alan G. Marshall - Tallahassee FL, US

Assignee:

FLORIDA STATE UNIVERSITY RESEARCH FOUNDATION - Tallahassee FL

International Classification:

C12Q 1/02
C07C 229/22
C07C 229/08

US Classification:

435 29, 562567, 562553

Abstract:

A method is provided for quantifying endogenous sphingolipids in a biological system. The method includes preparing one or more isotope labeled amino acids; introducing the isotope labeled amino acids into a biological system; extracting and separating a sphingolipid-containing fraction from the biological system; and quantifying the amount of endogenous sphingolipids in the biological system. The isotope-labeled amino acid may include a non-essential amino acid, and the method may further include adding an amino acid synthesis inhibitor into the biological system. Systems and kits for quantifying endogenous sphingolipids also are disclosed.

US Patent:

20130210162, Aug 15, 2013

Filed:

Feb 8, 2013

Appl. No.:

13/763159

Inventors:

Florida State University Research Foundation, Inc. - , US
RYAN P. RODGERS - Tallahassee FL, US
CHRISTOPHER L. HENDRICKSON - Tallahassee FL, US
ALAN G. MARSHALL - Tallahassee FL, US

Assignee:

FLORIDA STATE UNIVERSITY RESEARCH FOUNDATION, INC. - Tallahasse FL

International Classification:

G01N 27/62

US Classification:

436173, 422 83

Abstract:

Systems, devices, and methods, operational at atmospheric pressure, involving a conical member having an outlet positioned relative to an inlet of a mass spectrometer inlet capillary; a tungsten electrode positioned between the conical member and the inlet of the mass spectrometer inlet capillary; a foil membrane disposed within the conical member, the foil membrane having a first surface, and a second surface opposed to the first surface; a laser directing laser pulses at the second surface of the foil membrane to create a shockwave to vaporize one or more analytes deposited on the first surface; a reagent gas inlet stream positioned relative to the foil membrane to pass a reagent gas across the foil member to transport vaporized analytes: away from the foil membrane, through the outlet of the conical member, through a corona discharge generated by the tungsten electrode, and into the inlet capillary of a mass spectrometer.