ABRIDGED ION TRAP - TIME OF FLIGHT MASS SPECTROMETER
First Claim
Patent Images
1. An abridged trap-TOF mass analyzer comprising:
- an abridged linear ion trap witha first plurality of rectilinear electrode structures, each structure having a substantially planar face with a first dimension and a second dimension perpendicular to the first dimension and being constructed so that a voltage applied across the second dimension produces at the planar face an electrical potential whose amplitude is a linear function of position along the second dimension,a mechanism that positions the first plurality of rectilinear electrode structures so that, for each electrode structure, the first dimension extends along the central axis and the planar faces of the electrode structures are parallel and positioned symmetrically about the central axis, andone or more trapping electrode assemblies that produce axially confining fields before and after the first plurality of electrode structures along the central axis;
a drift region; and
an ion detector.
1 Assignment
0 Petitions
Accused Products
Abstract
An improved trap-TOF mass spectrometer has a set of electrodes arranged to produce both a quadrupolar RF confining field and a substantially homogeneous dipole field. In operation, ions are first confined by the RF field and then, at a selected time, the RF confining field is discontinued and the dipole field is used to accelerate the ions so as to initiate a TOF MS analysis. The apparatus of the present invention may be used alone or in conjunction with other analyzers to produce mass spectra from analyte ions.
-
Citations
28 Claims
-
1. An abridged trap-TOF mass analyzer comprising:
-
an abridged linear ion trap with a first plurality of rectilinear electrode structures, each structure having a substantially planar face with a first dimension and a second dimension perpendicular to the first dimension and being constructed so that a voltage applied across the second dimension produces at the planar face an electrical potential whose amplitude is a linear function of position along the second dimension, a mechanism that positions the first plurality of rectilinear electrode structures so that, for each electrode structure, the first dimension extends along the central axis and the planar faces of the electrode structures are parallel and positioned symmetrically about the central axis, and one or more trapping electrode assemblies that produce axially confining fields before and after the first plurality of electrode structures along the central axis; a drift region; and an ion detector. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15)
-
-
16. A method of mass analyzing ions comprising:
-
(a) providing an abridged trap-TOF mass analyzer comprising a first abridged linear ion trap with a first plurality of rectilinear electrode structures, each structure having a substantially planar face with a first dimension and a second dimension perpendicular to the first dimension and being constructed so that a voltage applied across the second dimension produces an electrical potential at the planar face whose amplitude is a linear function of position along the second dimension;
a mechanism that positions the first plurality of rectilinear electrode structures so that, for each electrode structure, the first dimension extends along the central axis and the planar faces of the electrode structures are parallel and positioned symmetrically about the central axis; and
one or more trapping electrode assemblies which can be used to produce axially confining fields before and after the first plurality of electrode structures along the central axis, a drift region and an ion detector;(b) injecting analyte ions into the first abridged linear ion trap along the central axis; (c) applying an RF potential across the second dimension of each of the electrode structures so as to produce a multipole field to focus the analyte ions toward the central axis; (d) discontinuing the RF potential; (e) applying a DC potential to one of (i) between the plurality of electrode structures and (ii) across the second dimensions of the electrode structures so that a first substantially homogeneous dipole field is established to accelerate the analyte ions out of the first abridged linear ion trap and into the drift region; and (f) detecting the ions. - View Dependent Claims (17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27)
-
-
28. An abridged trap-TOF mass analyzer comprising:
-
an abridged Paul trap with a plurality of planar electrodes positioned perpendicularly to a central axis at equal intervals along the central axis, each electrode having a circular central aperture centered on the central axis, the plurality of electrodes arranged so that the radii of the central apertures increases linearly from a minimum radius to a maximum radius with respect to increasing position along the central axis and then decreases linearly from the maximum radius to the minimum radius with respect to increasing position along the central axis, and a source that applies voltages to each electrode, the voltage applied to each electrode being a linear function of position along the central axis; a field free drift region; and an ion detector.
-
Specification