GC-APPI-Orbitrap-mass spectrometer ion source

Atmospheric pressure photoionization (APPI) shows high sensitivity for non-polar, and chlorinated environmental pollutants as well as for drugs and steroids when applied in liquid chromatography / mass spectrometry. Recent developments show the high affinity to introduce APPI in gas chromatography / mass spectrometry (GC/MS).

A new gas chromatography-APPI-Orbitrap-mass spectrometry interface with an outstanding sensitivity, that was recently developed at the University of Wuppertal, was further investigated in this study to determine the features of this new analytical platform. The adaptability for the analysis of environmental pollutants was shown with the EPA-8270 Mix, and 63 out of 78 compounds were successfully determined. Furthermore the ionization efficiency for 95 compounds were specified showing a dependency of the ionization energy. Additionally the adaptability of the new platform for compound-specific stable isotope analysis of chlorinated compounds was examined and for the analysis of complex biological samples in the field of metabolomics. In both fields it was possible to show a first fitness for purpose.

The results of the optimization procedure indicated that in the current setup the very old Orbitrap MS (without S-lense) is the limiting factor. It is expected that the full capacities of the analytical platform could be evaluated using an Orbitrap instrument with higher scan rates and higher resolution power.

Work was done by Oliver Knoop