Methods are described for measuring the amount of a vitamin B2 in a sample. More specifically, mass spectrometric methods are described for detecting and quantifying vitamin B2 in a sample utilizing on-line extraction methods coupled with tandem mass spectrometric techniques.

A system and method is described for characterizing glycopeptides which includes a first quadrupole mass filter, a multipole rod set of an ion guide, a lens electrode, an ExD device and a mass analyzer. The multipole rod set is adapted to receive a radial radio frequency (RF) trapping voltage and a radial dipole direct current (DC) voltage The lens electrode is adapted to receive an axial trapping alternating current (AC) voltage and a DC voltage. The ExD device performs electron capture dissociation or electron transfer dissociation, the ExD device being positioned so that an entrance of the ExD device is disposed on the other side of the lens electrode opposite the multipole rod set. The mass analyzer is positioned at an exit of the ExD device for receiving ions from the ExD device.

Methods are described for measuring the amount of a vitamin B2 in a sample. More specifically, mass spectrometric methods are described for detecting and quantifying vitamin B2 in a sample utilizing on-line extraction methods coupled with tandem mass spectrometric techniques.

After a precursor ion has been captured within an ion trap (2), electrons having a high energy equal to or higher than 30 eV are introduced from an electron irradiator (7) into the ion trap (2) to increase the number of charges of the ion through an interaction between the electrons and the ion. Hydrogen radicals are subsequently introduced from a hydrogen radical irradiator (5) into the ion trap (2) to dissociate the ion by a hydrogen-attachment dissociation (HAD) method. The larger the number of charges of the ion is, the higher the dissociation efficiency by the HAD method becomes. Therefore, for example, even in the case of using an ion source in which most of the generated ions are singly charged ions as in a MALDI ion source, the dissociation efficiency can be improved by increasing the number of charges of the precursor ion within the ion trap (2).

Methods are described for measuring the amount of a vitamin B2 in a sample. More specifically, mass spectrometric methods are described for detecting and quantifying vitamin B2 in a sample utilizing on-line extraction methods coupled with tandem mass spectrometric techniques.

Methods and systems are provided herein for selectively removing product ions resulting from an ECD dissociation event from the interaction region of an ECD reaction cell, while other precursor peptide ions continue to undergo ECD within the interaction region, thereby reducing or preventing the occurrence of multiple electron capture events by the product ions. In some aspects, the preferential extraction of product ions from the interaction region during the ECD reaction can occur without an auxiliary AC field being generated within the interaction region. Additionally, in some aspects, the methods and systems disclosed herein can subject the various product ions to a non-dissociative charge reduction via exposure to reagent ions of the opposite polarity so as to selectively concentrate product ions to a lower charge state.

In a method and apparatus for electron ionization liquid chromatography mass spectrometry (EI-LC-MS) analysis liquid chromatograph output solvent flow is directed together with spray formation gas into a spray formation and vaporization chamber for forming spray droplets which are vaporized to form vaporized sample compounds at a pressure equal to or greater than ambient pressure. A minor portion is conveyed into a heated flow restriction capillary that directly connects the spray formation and vaporization chamber and a non-fly-through electron ionization ion source of a mass spectrometer located inside a vacuum chamber. A major portion is released to atmosphere so that it does not enter the flow restriction capillary and therefore does not reach the non-fly-through electron ionization ion source. Also disclosed is an interface for a unified dual-mode mass spectrometer system for performing gas chromatography mass spectrometry (GC-MS) or electron ionization liquid chromatography mass spectrometry (EI-LC-MS) analyses.

According to an embodiment, a mass spectrometry apparatus includes a beam irradiator, a laser irradiator, a mass spectrometer and a controller. The beam irradiator irradiates a sample with an ion beam. The laser irradiator irradiates a space above the sample with laser light. The mass spectrometer performs mass spectrometry of an ionized particle. The controller controls at least one of the laser irradiator and the mass spectrometer on the basis of an analysis result of the mass spectrometer.

A linear ion trap system includes a linear ion trap having at least two discrete trapping regions for processing ions. An RF electrical potential generator produces two RF waveforms applied to a pair of pole electrodes of the linear ion trap forming a RF trapping field component to trap ions radially. A multi-output DC electrical potential generator produces a first set of multiple DC field components superimposed to the RF trapping field component and distributed across the length of the linear ion trap to control ions axially. A control unit is configured to switch the DC electrical potentials and DC field components collectively forming a first trapping region of the at least two discrete trapping regions that is populated with ions to alter ion potential energy from a first level to a second level, and to enable at least a first ion processing step in at least one of the first and second levels.

Electron capture dissociation (ECD) is performed by transmitting an electron beam through a cell along an electron beam axis, generating plasma in the cell by energizing a gas with the electron beam, and transmitting an ion beam through the interaction region along an ion beam axis to produce fragment ions. Generating the plasma forms an interaction region in the cell spaced from and not intersecting the electron beam, and including low-energy electrons effective for ECD. The ion beam axis may be at an angle to and offset from the ion beam axis, such that the electron beam does not intersect the ion beam.