Aim of this research project is the detection and analysis of pesticide and drug residues present in ground and surface water. Electrospray ionization (ESI) is a commonly used ionization method for the analysis of liquids. We coupled an electrospray ionization source with a 75mm desolvation tube to our high resolution ion mobility spectrometer with a 75mm drift tube length. One major advantage of our setup is that the desolvation region of the ESI-IMS can be heated separately from the drift region.
With this setup we reach e.g. a resolving power of R=100 for tetraalkylammonium halides and at a water content of 50% and after 2s of averaging a LOD of 4 µg/l for bentazon.