The ion trap comprises a multipole electrode assembly, a first confining electrode, and a second confining electrode. The multipole electrode assembly is configured to confine ions of the first polarity to an ion channel extending in an axial direction of the multipole electrode assembly. The first confining electrode is provided adjacent to the multipole electrode assembly and extends in the axial direction of the multipole electrode assembly. The second confining electrode is provided adjacent to the multipole electrode assembly and extends in the axial direction of the multipole electrode assembly aligned with the first confining electrode. The first and second confining electrodes are spaced apart in the axial direction in order to define an ion confining region of the ion channel between the first and second confining electrodes. The first and second confining electrodes are configured to receive a DC potential of the first polarity to further confine ions within the ion channel in the ion confining region.

A system for analyzing a sample includes a linear ion trap, an insert DC electrode, a voltage controller, and an RF control circuitry. The linear ion trap includes a first pair of trap electrodes and a second pair of trap electrodes spaced apart from each other and surrounding a trap interior. An electrode of the second pair of trap electrodes includes a trap exit. The insert DC electrode is positioned adjacent to the trap exit. The voltage controller applies a DC voltage to the insert DC electrode. The RF control circuitry applies a main RF voltage to the first pair of trap electrodes, applies a portion of the main RF to the second pair of trap electrodes, increases the main RF applied to the first pair of trap electrodes, and applies an auxiliary RF voltage to the second pair of trap electrodes.

Mass separators are provided that can include at least one electrode component having a surface, in one cross section, defining at least two runs associated via at least one rise, the rise being orthogonally related to the runs. Mass selective detectors are provided that can include at least a first pair of opposing electrodes with each of the opposing electrodes having a complimentary surface, in one cross section, defining at least two runs associated via a rise. Methods for optimizing mass separation within a mass selective detector are also provided, including providing mass separation parameters; providing one set electrodes within the separator having a surface operatively aligned within the separator, the surface, in one cross section, defining at least two runs associated via a rise, the rise being orthogonally related to the runs; and modifying one or both of the rise and/or runs to achieve the mass separation parameters.

An apparatus for separating ions includes an electrode arrangement having a length extending between first and second ends. The first end is configured to introduce a beam of ions into an ion transmission space of the arrangement. An electronic controller applies an RF potential and a DC potential to an electrode of the electrode arrangement, for generating a ponderomotive RF electric field and a mass-independent DC electric field. The application of the potentials is controlled such that a ratio of the strength of the ponderomotive RF electric field to the strength of the mass-independent DC electric field varies along the length of the electrode arrangement. The generated electric field supports extraction of ions having different m/z values at respective different positions along the length of the electrode arrangement. Ions are extracted in one of increasing and decreasing sequential order of m/z ratio with increasing distance from the first end.

An ion trap (100) includes a first electrode pair (110) and a second electrode pair (130), each including a first conductive member (112) and a second conductive member (120) and facing each other so that the first conductive member (112) of the first electrode pair (110) is on a common plane with the second conductive member (120) of the second electrode pair (130) and so that the second conductive member (120) of the first electrode pair (110) is on a common plane with the first conductive member (112) of the second electrode pair (130), a gap (132) therebetween. A signal generator (210) generates a periodic signal (212) applied to the first conductive members (112). A phase shifter (216) generates a second periodic signal (218) that is 180 out of phase therewith applied to the second conductive members (120). Ions are trapped by a resulting electric field.

A mass selective ion trapping device includes a linear ion trap and a RF control circuitry. The ion trap includes a plurality of trap electrodes configured for generating a quadrupolar trapping field in a trap interior and for mass selective ejection of ions from the trap interior. The RF control circuitry is configured to apply a balanced AC voltage to the trap electrodes during a first period of time such that an AC voltage applied to a first pair of trap electrodes is of the same magnitude and of opposite sign to an AC voltage applied to a second pair of trap electrodes; apply unbalanced RF voltage to the second pair of trap electrodes during a second period of time; ramp the balanced AC voltage down and the unbalanced RF voltage up during a transition period; and eject ions from the linear ion trap after the second period of time.

In one aspect, a method of performing mass spectrometry is disclosed, which comprises ionizing a sample to generate a plurality of precursor ions, passing the precursor ions through a mass filter to select at least one subset of the ions, introducing the selected ions into a branched radiofrequency (RF) ion trap and subjecting at least a portion of said selected precursor ions to fragmentation within the ion trap so as to generate a first plurality of fragment ions. The method can further include isolating at least a portion of the first plurality of fragment ions in at least one branch of the branched RF ion trap, removing unwanted fragment ions, releasing the remaining ions from said at least one branch and subjecting at least a portion thereof to fragmentation so as to generate a second plurality of fragment ions. Any combination of collision induced dissociation (CID) and electron activation dissociation (EAD) can be employed for fragmenting the ions.

Provided are improved toroidal ion traps and methods of design of such ion traps. Toroidal ion traps include an inner electrode comprising a first surface; an outer electrode at least partially circumferentially surrounding the inner electrode, the outer electrode comprising a second surface substantially facing the first surface, wherein the outer electrode is spaced apart from the first surface in a radial direction; a first end electrode comprising a third surface; a second end electrode comprising a fourth surface substantially facing the third surface; an axis of rotation extending through the inner electrode; and wherein: the first, second, third, and fourth surfaces define an ion confinement cavity and at least portions of each of the first, second, third, and fourth surfaces extend through or along iso-potential surfaces associated with a linear combination of toroidal multipoles to generate an electric field extending through slits in the first and second end electrodes.

An ion trap (100) includes a first electrode pair (110) and a second electrode pair (130), each including a first conductive member (112) and a second conductive member (120) and facing each other so that the first conductive member (112) of the first electrode pair (110) is on a common plane with the second conductive member (120) of the second electrode pair (130) and so that the second conductive member (120) of the first electrode pair (110) is on a common plane with the first conductive member (112) of the second electrode pair (130), a gap (132) therebetween. A signal generator (210) generates a periodic signal (212) applied to the first conductive members (112). A phase shifter (216) generates a second periodic signal (218) that is 180 out of phase therewith applied to the second conductive members (120). Ions are trapped by a resulting electric field.

A mass selective ion trapping device includes a linear ion trap and a RF control circuitry. The ion trap includes a plurality of trap electrodes configured for generating a quadrupolar trapping field in a trap interior and for mass selective ejection of ions from the trap interior. The RF control circuitry is configured to apply a balanced AC voltage to the trap electrodes during a first period of time such that an AC voltage applied to a first pair of trap electrodes is of the same magnitude and of opposite sign to an AC voltage applied to a second pair of trap electrodes; apply unbalanced RF voltage to the second pair of trap electrodes during a second period of time; ramp the balanced AC voltage down and the unbalanced RF voltage up during a transition period; and eject ions from the linear ion trap after the second period of time.