Thermo Fisher Scientific (Bremen) Gmbh

Mikhail Belov

Dmitry E Grinfeld

Eduard V Denisov

Gregor Quiring

Lothar Rottman

A method of operating a collision cell () in a mass spectrometer is disclosed. The collision cell comprises an entrance aperture (), an exit aperture () and electrodes () for producing electric fields. The method comprises feeding ions in a forward axial direction (LD) through the entrance aperture into the collision cell, producing a first electric field to trap ions, and subsequently producing a second electric field to accelerate trapped ions in the forward axial direction. The method further comprises producing a gas flow (G) which is, at least at the entrance aperture () of the collision cell, contrary to the forward axial direction (LD), so as to reduce the kinetic energy of ions in dependence on their collisional cross sections. A collision cell arranged for carrying out the method is also disclosed, as well as a mass spectrometer comprising such a collision cell.

Interference suppression in mass spectrometer

Ions are injected into an orbital electrostatic trap. An ejection potential is applied to an ion storage device, to cause ions stored in the ion storage device to be ejected towards the orbital electrostatic trap. Synchronous injection potentials are applied to a central electrode of the orbital electrostatic trap and a deflector electrode associated with the orbital electrostatic trap, to cause the ions ejected from the ion storage device to be captured by the electrostatic trap such that they orbit the central electrode. Application of the ejection potential and application of the synchronous injection potentials are each started at respective different times, the difference in times being selected based on desired values of mass-to-charge ratios of ions to be captured by the orbital electrostatic trap.

Ion injection to an electrostatic trap

A method of analyzing macromolecular complex ions, such protein complex ions, by mass spectrometry and apparatus for performing the method, wherein the method comprises: introducing macromolecular complex ions into a first fragmentation device and trapping the complex ions therein for a trapping period; fragmenting the trapped complex ions in the first fragmentation device to produce monomer subunit ions; optionally selecting one or more species of subunit ions by m/z; introducing one or more of the species of subunit ions into a second fragmentation device, spatially separated from the first fragmentation device; fragmenting the subunit ions in the second fragmentation device to produce a plurality of first fragment ions of the subunit ions; and mass analyzing the first fragment ions in a mass analyzer, or subjecting the first fragment ions to one or more further steps of fragmentation to form further fragment ions and mass analyzing the further fragment ions.

Growing community of inventors

Bremen, Germany

Mikhail Belov