Characteristics and comparison of different radiofrequency-only multipole cooling cells

Various multipole cooling cells are widely used in mass spectrometry for their outstanding performance with regard to transmission and cooling effects. Among these, radiofrequency (RF)-only quadrupoles, hexapoles, and octopoles are routinely used in practical instrumentation. A study of their performance has been carried out using a house-built electrospray time-of-flight mass spectrometer equipped with three different multipole devices. In addition, a user-written program was developed using SIMION 7.0 to simulate ion transmission characteristics for the different devices utilized. Systematic experiments and simulations were performed with an RF-only quadrupole, hexapole, and octopole to study their theoretical and practical characteristics.