Page 416 - Tandem Techniques

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different types of interfaces employed in LC/MS tandem systems and is reproduced in Figure 9.57.

Figure 9.57
The Comparative Performance of the
Different Types of LC/MS Interfaces (ref. 50)
It is seen that the particle beam and the thermospray interfaces can cope with the widest range of
solvent polarities, whereas the electrospray and ionspray interfaces are not suitable for use with
dispersive solvents but are ideal for ionic solutions. It is also seen that the particle beam interface and
the thermospray interface operate well with high column flow rates. In contrast the electrospray and
continuous flow FAB interfaces are only effective at very low flow rates. The most versatile interfaces
with respect to handling a wide range of flow rates are the ion spray and atmospheric ionization
interfaces.

Synopsis

The LC/MS tandem systems are more complicated than their GC/MS counterparts, as the eluted
substances are mostly involatile, and are not efficiently ionized by electron impact or chemical
ionization processes. If