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mass spectrometer. They concluded that the LC/MS system, incorporating the transport interface,
behaved as a low-dispersion LC detector and consequently, could be used very effectively with small-
bore columns. In fact, once the eluent is deposited on the wire, and evaporation begins, the longitudinal
diffusion of the solutes along the surface becomes exceedingly small. Consequently the peak widths,
and the position of the peaks relative to one another, are 'frozen' on the transport medium, just as they
were when they left the column.

Hayes et al. [10] conducted a systematic study on the effect of the method of solvent deposition on the
transport medium on the overall performance of the LC/MS system. They designed a nebulizer to spray
the column eluent onto the moving belt, a diagram of which is shown in Figure 9.14.

Figure 9.14
The Spray Deposition Device for Belt Transport Interfaces
Reprinted with permission from M. J. Hayes, E. P.
Lanksmeyer, P. Vouroo and B. L. Karger, Anal. Chem,
55(1983)1745, Copyright 1983 American Chemical Society

A stainless steel tube, 0.0625 in. O.D. and 0.007 in. I.D., is placed concentrically inside a Pyrex tube
that carries the nebulizing gas. The Pyrex tube is held inside an outer steel tube by means of a screw cap
and an O ring. The effects of nebulizer temperature and gas flow rate, on the integrity of the elution
curve produced by the interface, were investigated.