Quadrupole Mass Analyzers

In quadrupole mass analyzing devices, electric fields are used to separate ions according to their mass-to-charge ratio (m/z) as they pass along the central axis of four parallel equidistant rods (or poles) that have fixed (DC) and alternating (RF) voltages applied to them. This module will explain the theory and principles of quadrupole mass analyzers.

Topics include:

• Quadrupole rods
• Quadrupole voltages
• Quadrupole electrostatic fields
• Quadrupole ion trajectories
• Equations of motion
• Quadrupole mass analyzers - mass gain and offset
• Quadrupole resolution and sensitivity
• Quadrupole data acquisition modes
• Quadrupole scan vs. selected ion modes
• RF only ion bridges
• Quadrupole mass accuracy
• Quadrupole performance limitations
• Quadrupole scanning speeds