Quadrupole ion trap vs. Penning trap

[lelanddavis]

Hello. I have been reading up on quadrupole ion traps used in many mass spectrometers (I was trying to learn about mass spectrometry in relation to biological samples), and heard wind of "Penning traps" which also use electric quadrupoles for trapping, usually spoken of in conjunction with particle physics. The similarities are such that I am confused. What are the differences (are there any?) between Penning traps and the quadrupole traps used in mass spectrometers? Does the electric field for the dipoles oscillate between the end plates and the ring electrode on a Penning trap as it does for the quadrupole trap? (Does a Penning trap have ring electrodes and end plates?) I am confused.

 

[Valerie Park]

The main difference between Penning traps and quadrupole ion traps used in mass spectrometers is the purpose for which they are used. Quadrupole ion traps are used to trap and focus ions for use in mass spectrometry, whereas Penning traps are primarily used for trapping and studying charged particles, such as electrons and ions, in particle physics research.Penning traps have cylindrical electrodes and a ring electrode, whereas quadrupole ion traps have four parallel rods arranged in an "X" shape. The electric field for the dipoles does oscillate between the end plates and the ring electrode on a Penning trap, but this is not the case for a quadrupole trap, which has a static electric field. Additionally, in a Penning trap, the electric field is much stronger than in a quadrupole trap.