Moving-belt interface spray deposition used

Spray deposition A method used to apply HPLC eluate in later versions of the moving-belt interface to provide a uniform layer of mobile phase on the belt and thus minimize the production of droplets. 

The solvent elimination problem became less of a problem with the commercialization of microbore columns. Hayes et al. (54) studied gradient HPLC-MS using microbore columns and a moving-belt interface. The heart of the system was the spray deposition device designed to be compatible with microbore-column flow rates. Nebulization of the eluent was found to be applicable to a variety of mobile-phase compositions and thus was readily compatible with gradient elution. Figure 13 shows a comparison of UV detection with that obtained with the HPLC-MS system. Applications of this system were demonstrated on water from coal gasification processes. 

The LC/MS moving belt interface was modified so that the column effluent was deposited on the belt in a fine spray. With this system, the LC/MS interface is capable of efficient operation with the mobile phases used at flow rates up to 0.2 cm /min. There is no significant loss of resolution or efficiency in going from the absorbance detector to... 

Figure 13. Comparison of UV and MS chromatograms using a 1.0-mm i.d. column packed with a 5-pm diameter Supelcosil C-18. LC-MS interface used aerosol spray deposition on a moving belt. Peaks correspond from left to right to 0.2 pg each of resorcinol, 1,5-dihydroxynaphthol, and 2-methyl-phenol. Conditions 41% acetonitrile and 59% water (v/v) with 0.1% trifluoro-acetic acid at a flow rate of 40 pL/min. A, UV trace at 280 nm, 0.015 AUFS B, MS trace, selected ion chromatogram. (Reproduced from reference 54.

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