A MOVING BELT DEVICE TO COUPLE HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY AND CHEMICAL-REACTION INTERFACE MASS-SPECTROMETRY

A device is described to enable selective detection of C-13- and N-15-labeled compounds following separation by high-performance liquid chromatography (HPLC). A thermospray vaporizer deposits the materials eluting from the HPLC column onto a continuously moving endless belt. The belt carries these compounds into the chemical reaction interface, where a microwave-induced helium plasma converts complex organic molecules in the presence of a reactant gas into small stable molecules that are detected by the mass spectrometer. Chromatograms showing only compounds enriched with C-13 and N-15 can be obtained by subtracting the abundance of naturally occurring isotopes from the observed M + 1 signal. This work demonstrates the feasibility of this approach and encourages its further development.