Atmospheric Pressure Free Liquid Infrared MALDI Mass Spectrometry: Towards a unified ESI/MALDI - Liquid Chromatography Interface

摘要

A new concept of an ion source working at ambient conditions is presented. Successful application of the continuous source to the mass analysis of peptide samples in the flow injection mode. Well suited for HPLC applications, where flow rates >100(mu)l/min are required. Suitability as online LC-MS interface has been demonstrated, performing a peptide mass fingerprint mapping on BSA tryptic digest. Liquid delivery based on a droplet-on-demand basis improved sample consumption and therefore LOD by about three orders of magnitude (down to 20 attomole). Development of a nano-HPLC MS droplet-on-demand version with attomole sensitivity seems to be promising (esp. when dealing with limited sample amounts).