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Craig M. Whitehouse, Branford US

Craig M. Whitehouse, Branford, CT US

Patent application numberDescriptionPublished
20080296495RF Surfaces and RF Ion Guides - Apparatus and methods are provided for trapping, manipulation and transferring ions along RF and DC potential surfaces and through RF ion guides Potential wells are formed near RF-field generating surfaces due to the overlap of the radio-frequency (RF) fields and electrostatic fields created by static potentials applied to surrounding electrodes. Ions can be constrained and accumulated over time in such wells During confinement, ions may be subjected to various processes, such as accumulation, fragmentation, collisional cooling, focusing, mass-to-charge filtering, spatial separation ion mobility and chemical interactions, leading to improved performance in subsequent processing and analysis steps, such as mass analysis. Alternatively, the motion of ions may be better manipulated during confinement to improve the efficiency of their transport to specific locations, such as an entrance aperture into vacuum from atmospheric pressure or into a subsequent vacuum stage.12-04-2008
20090008547ATMOSPHERIC PRESSURE ION SOURCE PERFORMANCE ENHANCEMENT - Electrospray ionization sources interfaced to mass spectrometers have become widely used tools in analytical applications. Processes occurring in Electrospray (ES) ionization generally include the addition or removal of a charged species such as H+ or other cation to effect ionization of a sample species. Electrospray includes ionization processes that occur in the liquid and gas phase and in both phases ionization processes require a source or sink for such charged species. Electrolyte species, that aid in oxidation or reduction reactions occurring in Electrospray ionization, are added to sample solutions in many analytical applications to increase the ES ion signal amplitude detected by a mass spectrometer (MS). Electrolyte species that may be required to enhance an upstream sample preparation or separation process may be less compatible with the downstream ES processes and cause reduction in MS signal. A new set of Electrolytes has been found that increases positive and negative polarity analyte ion signal measured in ESMS analysis when compared with analyte ESMS signal achieved using more conventional electrolytes. The new electrolyte species increase ES MS signal when added directly to a sample solution or when added to a second solution flow in an Electrospray membrane probe. The new electrolytes can also be added to a reagent ion source configured in a combination Atmospheric pressure ion source to improve ionization efficiency.01-08-2009
20090095899ATMOSPHERIC PRESSURE ION SOURCE PERFORMANCE ENHANCEMENT - Electrospray ionization sources interfaced to mass spectrometers have become widely used tools in analytical applications. Processes occurring in Electrospray (ES) ionization generally include the addition or removal of a charged species such as H+ or other cation to effect ionization of a sample species. Electrospray includes ionization processes that occur in the liquid and gas phase and in both phases ionization processes require a source or sink for such charged species. Electrolyte species, that aid in oxidation or reduction reactions occurring in Electrospray ionization, are added to sample solutions in many analytical applications to increase the ion signal amplitude generated in Electrospray and detected by a mass spectrometer (MS) Electrolyte species that may be required to enhance an upstream sample preparation or separation process may be less compatible with the downstream ES processes and cause reduction in MS signal New Electrolytes have been found that increase positive and negative polarity analyte ion signal measured in ESMS analysis when compared with analyte ESMS signal achieved using more conventional electrolytes The new electrolyte species increase ES MS signal when added directly to a sample solution or when added to a second solution flow in an Electrospray membrane probe. It has also been found that running the ES membrane probe with specific Electrolytes in the second solution of the ES membrane probe have been found to enhance ESMS signal compared to using the same electrolytes directly in the sample solution being Electrosprayed The new electrolytes can be added to a reagent ion source configured in a combination Atmospheric pressure ion source to improve ionization efficiency.04-16-2009
20090095900ATMOSPHERIC PRESSURE ION SOURCE PERFORMANCE ENHANCEMENT - Electrospray ionization sources interfaced to mass spectrometers have become widely used tools in analytical applications. Processes occurring in Electrospray (ES) ionization generally include the addition or removal of a charged species such as H+ or other cation to effect ionization of a sample species. Electrospray includes ionization processes that occur in the liquid and gas phase and in both phases ionization processes require a source or sink for such charged species. Electrolyte species, that aid in oxidation or reduction reactions occurring in Electrospray ionization, are added to sample solutions in many analytical applications to increase the ion signal amplitude generated in Electrospray and detected by a mass spectrometer (MS) Electrolyte species that may be required to enhance an upstream sample preparation or separation process may be less compatible with the downstream ES processes and cause reduction in MS signal. New Electrolytes have been found that increase positive and negative polarity analyte ion signal measured in ESMS analysis when compared with analyte ESMS signal achieved using more conventional electrolytes. The new electrolyte species increase ES MS signal when added directly to a sample solution or when added to a second solution flow in an Electrospray membrane probe. It has also been found that running the ES membrane probe with specific Electrolytes in the second solution of the ES membrane probe have been found to enhance ESMS signal compared to using the same electrolytes directly in the sample solution being Electrosprayed. The new electrolytes can be added to a reagent ion source configured in a combination Atmospheric pressure ion source to improve ionization efficiency.04-16-2009
20090218486Multipole ion guide interface for reduced background noise in mass spectrometry - Ions that are transported from an ion source to a mass spectrometer for mass analysis are often accompanied by background particles such as photons, neutral species, and cluster or aerosol ions which originate in the ion source. Background particles are also produced by scattering and neutralization of ions during collisions with background gas molecules in higher pressure regions with line-of-sight to the mass spectrometer detector. In either case, such background particles produce noise in mass spectra. Apparatus and methods are provided in which a multipole ion guide is configured to efficiently transport ions through multiple vacuum stages, while preventing background particles, produced both in the ion source and along the ion transport pathway, from reaching the detector, thereby improving signal-to-noise in mass spectra.09-03-2009
20110006198ATMOSPHERIC PRESSURE ION SOURCE PERFORMANCE ENHANCEMENT - Electrospray ionization sources interfaced to mass spectrometers have become widely used tools in analytical applications Processes occurring in Electrospray (ES) ionization generally include the addition or removal of a charged species such as II+ or other cation to effect ionization of a sample species. Electrospray includes ionization processes that occur in the liquid and gas phase and in both phases ionization processes require a source or sink for such charged species. Electrolyte species, that aid in oxidation or reduction reactions occurring in Electrospray ionization, are added to sample solutions in many analytical applications to increase the ES ion signal amplitude detected by a mass spectrometer (MS). Electrolyte species that may be required to enhance an upstream sample preparation or separation process may be less compatible with the downstream ES processes and cause reduction in MS signal. A new set of Electrolytes has been found that increases positive and negative polarity analyte ion signal measured in ESMS analysis when compared with analyte ESMS signal achieved using more conventional electrolytes. The new electrolyte species increase ES MS signal when added directly to a sample solution or when added to a second solution flow in an Electrospray membrane probe. The new electrolytes can also be added to a reagent ion source configured in a combination Atmospheric pressure ion source to improve ionization efficiency.01-13-2011
20110220789Sample Component Trapping, Release, and Separation with Membrane Assemblies Interfaced to Electrospray Mass Spectrometry - The invention provides a method and apparatus for trapping, releasing and/or separating sample components in solution passing through a channel with or without packing material present by passing ion current through the channel driven by an electric field. A portion of the ion current comprises cation and/or anion species generated from second solution flows separated from the sample solution flow path by semipermeable membranes. Cation and/or Anion ion species generated in the second solution flow regions are transferred into the sample solution flow path through ion selective semipermeable membranes. Ion current moving along the sample solution flow path is controlled by varying the composition of the second solutions and/or changing the voltage between membrane sections for a given sample solution composition. The sample composition may also be varied separately or in parallel to enhance trapping, release and/or separation efficiency and range. The invention when interfaced to an Atmospheric Pressure Ion Source, that may include Electrospray Ionization, with mass spectrometric analysis enables independent control of the on-line sample separation process and the Atmospheric Pressure Ion Source or Electrospray ionization processes.09-15-2011
20110287554ATMOSPHERIC PRESSURE ION SOURCE PERFORMANCE ENHANCEMENT - Electrospray ionization sources interfaced to mass spectrometers have become widely used tools in analytical applications. Processes occurring in Electrospray (ES) ionization generally include the addition or removal of a charged species such as H+ or other cation to effect ionization of a sample species Electrospray includes ionization processes that occur in the liquid and gas phase and in both phases ionization processes require a source or sink for such charged species. Electrolyte species, that aid in oxidation or reduction reactions occurring in Electrospray ionization, are added to sample solutions in many analytical applications to increase the ion signal amplitude generated in Electrospray and detected by a mass spectrometer (MS). Electrolyte species that may be required to enhance an upstream sample preparation or separation process may be less compatible with the downstream ES processes and cause reduction in MS signal. New Electrolytes have been found that increase positive and negative polarity analyte ion signal measured in ESMS analysis when compared with analyte ESMS signal achieved using more conventional electrolytes. The new electrolyte species increase ES MS signal when added directly to a sample solution or when added to a second solution flow in an Electrospray membrane probe. It has also been found that running the ES membrane probe with specific Electrolytes in the second solution of the ES membrane probe have been found to enhance ESMS signal compared to using the same electrolytes directly in the sample solution being Electrosprayed. The new electrolytes can be added to a reagent ion source configured in a combination Atmospheric pressure ion source to improve ionization efficiency.11-24-2011

Patent applications by Craig M. Whitehouse, Branford, CT US