Band pass extraction from an ion trapping device and TOF mass spectrometer sensitivity enhancement

A method for mass selectively extracting ions, comprising:

• applying in combination a radial dipole direct current (DC) voltage to a multipole rod set of an ion guide, an axial trapping alternating current (AC) voltage to a lens electrode of the ion guide, a radial radio frequency (RF) trapping voltage amplitude to the multipole rod set and a DC voltage to the lens electrode using a processor in order to extract a bandpass mass range of ions trapped in the multipole rod set;
• wherein the multipole rod set is adapted to receive the radial RF trapping voltage and the radial dipole voltage DC and wherein the lens electrode is positioned at one end of the multipole rod set to extract ions trapped by the multipole rod set and adapted to receive the axial trapping AC voltage and the DC voltage;
• applying the DC voltage on the lens electrode that is less than the radial dipole DC voltage applied to the multipole rod set when the multipole rod set is used to trap positive ions using the processor;
• and
• applying the DC voltage on the lens electrode that is greater than the radial dipole DC voltage applied to the multipole rod set when the multipole rod set is used to trap negative ions using the processor.

A computer program product, comprising a non-transitory and tangible computer-readable storage medium whose contents include a program with instructions being executed on a processor so as to perform a method for mass selectively extracting ions, the method comprising:

• providing a system, wherein the system comprises one or more distinct software modules, and wherein the distinct software modules comprise a control module;
• and
• applying in combination a radial dipole direct current (DC) voltage to a multipole rod set of an ion guide and an axial trapping alternating current (AC) voltage to a lens electrode of the ion guide, a radial radio frequency (RF) trapping voltage amplitude to the multipole rod set and a DC voltage to the lens electrode using the control module in order to extract a bandpass mass range of ions trapped in the multipole rod set;
• wherein the multipole rod set is adapted to receive the radial RF trapping voltage and the radial dipole DC voltage and wherein the lens electrode is positioned at one end of the multipole rod set to extract ions trapped by the multipole rod set and adapted to receive the axial trapping AC voltage and the DC voltage;
• wherein the processor applies the DC voltage on the lens electrode that is less than the radial dipole DC voltage that the processor applies to the multipole rod set when the multipole rod set is used to trap positive ions;
• and
• wherein the processor applies the DC voltage on the lens electrode that is greater than the radial dipole DC voltage that the processor applies to the multipole rod set when the multipole rod set is used to trap negative ions.