Matching and optimization of combined 3DQIT and TOFMS

Combination of Three Dimensional Quadrupole Ion Trap and Time Of Flight Mas s Spectrometer is very interesting because they both rely on time though in a different manner. The 3DQIT can accumulate many ions of which the desire d ions can be selected and kept for a very long period of time. Ions can su bsequently be extracted in a short burst from the 3DQIT to be sent in a TOF MS. This process can be eased if the trapped ions are cooled by collisions with gas molecules inside the trap. We will discuss from the basic principl es of physics what are the best conditions leading the maximum number of us able ions to penetrate in the TOFMS while keeping the resolving power at an acceptable level. (C) 1999 Elsevier Science B.V. All rights reserved.