Application of a combined liquid chromatographic-mass spectrometric instrument using an interface for direct liquid introduction

Abstract A liquid chromatographic (LC)-mass spectrometric interface based on a new concept allows better introduction of LC effluents into the source and has a higher sensitivity than the standard system. This system operates in two steps: evaporation of a part of the solvent from LC stream and droplets of large diameter and the use of the gaseous mass obtained to achieve nebulization of the droplets. Finally evaporation and desolvation of the LC effluents are carried out. There is the possibility of breaking up molecular associations and of introducing compounds into the solvents such as hydrazine and nitromethane, which are used as reactant gases, leading to different sovlent effects and remarkable changes of mass spectral patterns and ultimately the use of pure water as solvent. Spectra of labile compounds of high molecular weight are shown.