1
Mark E Bier, John E P Syka: Ion trap mass spectrometer system and method. Finnigan Corporation, Flehr Hohbach Test Albritton & Herbert, May 30, 1995: US05420425 (179 worldwide citation)

The present invention relates generally to an ion trap mass spectrometer for analyzing ions and more particularly to a substantially quadrupole ion trap mass spectrometer with an enlarged ion occupied volume. Described herein are electrode geometries that enlarge the ion occupied volume. Improved io ...


2
George C Stafford, Paul E Kelley, David R Stephens: Method of mass analyzing a sample by use of a quadrupole ion trap. Finnigan Corporation, Flehr Hohbach Test Albritton & Herbert, September 10, 1985: US04540884 (164 worldwide citation)

In a quadrupole ion store or ion trap type mass spectometer, significantly improved mass selection is achieved by simultaneously trapping ions within the mass range of interest and then scanning the applied RF and DC voltages or the frequency .omega. to sequentially render unstable trapped ions of c ...


3
John E P Syka, John N Louris, Paul E Kelley, George C Stafford, Walter E Reynolds: Method of operating ion trap detector in MS/MS mode. Finnigan Corporation, Flehr Hohbach Test Albritton & Herbert, April 5, 1988: US04736101 (110 worldwide citation)

A simple and economical method of mass analyzing a sample by means of a quadrupole ion trap mass spectrometer in an MS/MS mode comprises the steps of forming ions within a trap structure, changing the RF and DC voltages in such a way that the ions with mass-to-charge ratios within a desired range wi ...


4
Xiao Guang Zhou: Interpretation of mass spectra of multiply charged ions of mixtures. Finnigan Corporation, Flehr Hohbach Test Albritton & Herbert, December 10, 1991: US05072115 (90 worldwide citation)

A chemical mixture is conveyed to a multiple charging apparatus, where multiply charged ions are formed. The multiply charged ions are then conveyed to a mass spectrometer which generates mass/charge spectrum data relating intensity to a range of mass/charge values. This mass/charge spectrum data is ...


5
Jae C Schwartz, Xaio Guang Zhou, Mark E Bier: Method and apparatus of increasing dynamic range and sensitivity of a mass spectrometer. Finnigan Corporation, Flehr Hohbach Test Albritton & Herbert, November 5, 1996: US05572022 (86 worldwide citation)

This invention is directed to a method and apparatus of increasing the dynamic range and sensitivity of an ion trap mass spectrometer with the use of external ionization. An increased number of sample ions are introduced into the mass spectrometer for mass analysis with the aid of an automatic ion s ...


6
John E P Syka, William J Fies Jr: Fourtier transform quadrupole mass spectrometer and method. Finnigan Corporation, Flehr Hohbach Test Albritton & Herbert, July 5, 1988: US04755670 (71 worldwide citation)

A quadrupole mass spectrometer in which a sample to be analyzed is ionized in a two or three dimensional electrostatic trapping field, and the ions in the range of the mass-to-charge ratios to be analyzed are excited at their characteristic frequencies of motion. The excited ions generate image curr ...


7
Michael Weber Grabau, Stephen C Bradshaw, John E P Syka: Method of increasing the dynamic range and sensitivity of a quadrupole ion trap mass spectrometer operating in the chemical ionization mode. Finnigan Corporation, Flehr Hohbach Test Albritton & Herbert, September 13, 1988: US04771172 (56 worldwide citation)

A method is disclosed for increasing the dynamic range and sensitivity of a quadrupole ion trap mass spectrometer operating in the chemical ionization mode. Prior to mass analysis, a prescan is performed with the ion trap and the ionization and reaction periods are adjusted to produce enough stored ...


8
Paul E Kelley, George C Stafford Jr, John E P Syka: Method of isolating a single mass in a quadrupole ion trap. Finnigan Corporation, Flehr Hohbach Test Albritton & Herbert, June 7, 1988: US04749860 (49 worldwide citation)

Method of isolating ions of selected mass in a quadrupole ion trap of the type including a ring electrode and end caps in which RF and AC voltages are applied to the ring electrode and end caps and scanned to trap a single ion of interest.


9
Michael Weber Grabau: Method of isolating a single mass or narrow range of masses and/or enhancing the sensitivity of an ion trap mass spectrometer. Finnigan Corporation, Flehr Hohbach Test Albritton & Herbert, April 4, 1989: US04818869 (43 worldwide citation)

The method of isolating ions of single mass or narrow range of masses in a three-dimensional ion trap comprising ionizing a sample in the trap at a low RF voltage, increasing the RF voltage and applying a DC voltage whereby to eject unwanted ions while isolating ions of said single mass or narrow ra ...


10
John N Louris, Dennis M Taylor: Method and apparatus for ejecting unwanted ions in an ion trap mass spectrometer. Finnigan Corporation, Flehr Hohbach Test Albritton & Herbert, June 28, 1994: US05324939 (41 worldwide citation)

A method and apparatus is described which determines a plurality of spaced discrete frequencies covering the range of frequencies of the characteristic motion of unwanted ions and processes said discrete frequencies to generate a plurality of time dependent voltage amplitude values which vary throug ...