Application of a new sample introduction system for FAB mass spectrometry

The interface for direct coupling of micro HPLC with FAB mass spectrometry has been evaluated as a simple sample introduction system using unstable and/or non-volatile compounds having higher molecular weight. The good reproducibility of chromatograms, little fluctuation and small tailing in chromatographic peak profiles, and the excellent quality of mass spectral patterns were obtained. High-molecular-weight compounds such as parathyroid hormone and insulin chain B could be introduced and ionized stably with high sensitivity.