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of efficient LC/FTIR transport interfaces, so may the same occur with LC/MS interfaces, particularly
with the advent of the new ionizing techniques.

Transport Interfaces:

The Wire Transport Detector

In 1974 Scott et al. [4] developed a moving wire transport system for transferring the solute from the
LC column to the ion source of the mass spectrometer. This interface allowed the use of electron impact
ionization, and so all the expected ion fragments were produced to facilitate interpretation of the
spectra. The basic principle was similar to that of the moving wire LC transport detector [5,6], and in
the original model, the wire train from the detector was modified for use with the LC/MS interface. A
diagram of the LC/MS transport interface is shown in Figure 9.9.

Figure 9.9
The Transport Interface for LC/MS

The column eluent passes over a moving stainless steel wire, 0.005 in O.D., coating it with a thin film
of column eluent. In order to enter the ion source, the wire passes through three orifices and two
chambers connected in series. Each chamber is connected to a vacuum pump that