Purdue Research Foundation

Beyond Genomics, Inc.

Scott A McLuckey

Yu Xia

James Mitchell Wells

Gavin E Reid

Hongling Han

Noubar Boghos Afeyan

Fred E Regnier

Yves LeBlanc

Sharon J Pitteri

Xiaorong Liang

Kerry M Hassell

Min He

Paul A Chrisman

An apparatus and method for a sample using a mass spectrometer is described, including, generating ions of a first polarity from an analyte using electrospray ionization; generating ions of a second polarity from a reagent; injecting the ions of the first polarity and ions of the second polarity in sequence into a chamber of the mass spectrometer such that the ions of the first polarity and the ions of the second polarity interact in the chamber to form analyte ions having the second polarity; and, analyzing the mass spectrum of the analyte ions of the second polarity. A reagent such as a polyamidomine is selected to preferentially yield analyte ions of the second polarity having a desired mass-to-charge ratio.

Method and apparatus for conversion of multiple analyte cation types to a single analyte anion type via ion/ion charge inversion

A method and apparatus for radial activation of transmission-mode electron transfer ion/ion reactions using a dipolar AC field applied transverse to a transit direction is disclosed. Increases in fragment ion yields and structural information from electron transfer dissociation (ETD) were observed. The method may be used for transmission mode ETD for relatively low charge states of peptides and proteins.

Method and apparatus for activation of cation transmission mode ion/ion reactions

A method of controlling ion parking in an ion trap includes generating a trapping field for trapping cations and anions, and applying a tailored waveform during a period when ion/ion reactions occur to park first generation product ions with m/z values that differ from those of a cation and an anion in selected m/z regions. In particular, the tailored waveform inhibits simultaneously the reactions of ions of disparate m/z ratios.

Parallel ion parking in ion traps

A method an apparatus for analyzing biomolecules is described. The method includes injecting and storing one species of ionized molecule in a linear ion trap and injecting second species of oppositely polarity ionized molecule such that the second species is transmitted through the stored first species. The resultant reaction products may be analyzed by a mass analyzed taking account of the remaining charge values. In an aspect, a linear ion trap may be used as the reaction volume, and the ionized species injected along the axis of the trap in a substantially collinear manner. The mass analysis may be performed by mass selective axial ejection or by a mass spectrometer.

Method and apparatus for transmission mode ion/ion dissociation

A method and apparatus for identification of activating ions by collisions is described. The method uses a plurality of linear ion taps and a plurality of sources of ions and a mass measuring device. A first source is operated to dispense first ions into first trap, where the ions may be kinetically cooled. A second source is operated to dispense second ions into the first trap, where the first and the second ions are stored. Ions in the first trap are ejected so as to enter a second trap, where the ions are stored prior to mass spectrometry. The apparatus may use quadrupole rods to form the ion traps, and the voltage and pressure differences between the first and second traps are controllable values.

Method and apparatus for collisional activation of polypeptide ions

Processes and apparatus are described for the analysis of molecules or fragments thereof, which are capable of carrying multiple charges, by reacting the multiply charged molecules or fragments thereof with other ions using mass spectrometry.

Process for increasing ionic charge in mass spectrometry

A method of inhibiting the reaction between ions of opposite polarity is disclosed. The method includes exposing a population of ions to a resonance excitation frequency during a mass-to-charge altering reaction between a first subpopulation of ions and a second subpopulation of ions, the resonance excitation frequency being tuned to inhibit the mass-to-charge altering reaction between an ion of the first subpopulation of ions having a predetermined mass-to-charge ratio and an ion of the second subpopulation of ions so that when an ion of the first subpopulation of ions attains the predetermined mass-to-charge ratio, the ion having the predetermined mass-to-charge ratio is selectively inhibited from reacting with ions of the second subpopulation of ions.

Method of selectively inhibiting reaction between ions

The methods of the invention exploit the mass-to-charge ratio dependent motion of ions in an electrodynamic ion traps in synergy with a charge quenching process. In an electrodynamic ion trap, each mass-to-charge ratio is characterized by a unique set of frequencies of motion. Accordingly, by tailoring the time-varying electrical potential of the ion trap the invention controls which ions are allowed or retained in the ion trap and which ions are subjected to charge quenching reactions. Control of ion retention and charge quenching is used to improve sample throughput, dynamic mass range and signal discrimination in the mass spectrometry of multiply charged ions.

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West Lafayette, IN, United States of America

Scott A McLuckey