Agilent Technologies, Inc.

Hewlett-Packard Company

Jerry T Dowell

Charles William Russ, Iv

Steven Michael Fischer

Paul C Goodley

Timothy Herbert Joyce

John Christian Fjeldsted

Jeffery S Hollis

The present invention relates to, inter alia, methods and apparatuses for electron transfer dissociation (ETD) that vary the internal energy of precursor ions for ETD. The methods and apparatuses are particularly useful in mass spectrometry.

Efficient electron transfer dissociation for mass spectrometry

In a tandem mass spectrometer means are provided for molecular activation of ions prior to fragmentation. An embodiment of a tandem mass spectrometer comprises a first collision cell receiving analyte ions having an internal energy and a second collision cell situated downstream from the first collision cell wherein the first collision cell increases the internal energy of the analyte ions prior to entry of the ions into the second collision cell, the increase in internal energy imparted in the first collision cell alone being insufficient to fragment a substantial portion of the analyte ions. Another embodiment includes a collision cell with a heating device situated adjacent to the collision cell for controlling the temperature within the collision cell.

Molecular activation for tandem mass spectroscopy

The present invention provides an apparatus and method for use with a mass spectrometry system. The invention provides an ion source for providing radiative heating to an ionization region. The ion source includes a nanospray ionization device for producing ions and a conduit adjacent to the ionization device for receiving ions from the ionization device. The conduit includes a conductive material for providing indirect radiative heating to the ionization region. Direct radiative heating may also be provided using a heater in the conduit. The ion source may be used separately or in conjunction with the mass spectrometry system. When used in conjunction with a mass spectrometry system a detector may also be employed down stream from the device. A method for desolvating an analyte using the device is also disclosed.

Nanospray ionization device and method

A mass spectrometer method and apparatus improve resolution and sensitivity. A voltage supply is coupled to a mass filter for applying a radio frequency voltage and for operating at at least one selected frequency. An ion optical element such as an entrance lens is driven by a voltage supply that is phase coherent with the voltage applied to the mass filter. The ion beam is tailored so that the phase space relationship of the ions is more closely matched to the acceptance of the mass filter. The ions in the incoming beam are dynamically matched to the acceptance of the mass filter over each cycle of the voltage applied to the mass filter. The ion optical element may be a single entrance lens to which is applied only a single phase coherent voltage.

Method and apparatus for performance improvement of mass spectrometers

A mass spectrometer having an ionization source containing a chemical ionization chamber, wherein the inner surfaces of the chamber are formed from molybdenum to reduce adsorption, degradation and decomposition of an analyte and to reduce adverse ion/surface reactions is disclosed. A method of reducing adsorption, degradation and decomposition of an analyte and reducing adverse ion/surface reactions in an ionization source containing a chemical ionization chamber of a mass spectrometer including the step of forming the inner surfaces of the chamber from molybdenum is also disclosed. The inner surfaces may formed from molybdenum by constructing the entire chamber or the inner surfaces of the chamber from molybdenum; by depositing, plating or coating molybdenum on the inner surfaces of the chamber; or by a combination thereof. Suitable forms of molybdenum include solid molybdenum, mixtures containing at least 10% by weight molybdenum, and reaction products containing molybdenum.

Chemical ionization source for mass spectrometry

Selective trapping of ions from an external source into a quadrupole trap is accomplished by applying a parametric pump voltage to the quadrupole trap electrodes in such a phase as to extract energy from the ions, causing the ions to accumulate in the center of the trap. Pump voltage phase is controlled by the timing of the injection of ions into the trap relative to the absolute phase of the pump voltage. Optimum phasing results when the ion packet allowed into the trap through gating of the ion beam optics is sufficiently opposed by the field produced by the parametric pump voltage. The ions are also subjected to a normal RF trapping field.

Method and apparatus for selectively trapping ions into a quadrupole trap

The apparatus and method of the present invention multiplexes or gates particle beams to provide continuous data collection useful in time-of-flight mass spectrometry. The multiple particle beams are gated or combined to achieve an overall 100% duty cycle. This allows continuous data collection, thereby realizing the full advantages of abundance sensitivity and mass resolution in time-of-flight mass spectrometry.

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Portola Valley, CA, United States of America

Jerry T Dowell