LAUSR

A new ambient ion source was developed and its application to real samples has been demonstrated. This ion source is based on a previously build ion source using chemical ionization under atmospheric pressure and extractive electrospray ionization (DIP-APCI/EESI). To enhance the range of analytes, we added to this ion source a photoionization lamp to enable also photoionization, which allows the possibility to analyze polar (EESI), middle (APCI) and non-polar (APPI) analytes with the same source and with no or only a small change of the setup. In comparison with DIP-APCI, this ion source reaches similar analytical limits but shows better sensitivity for some aromatic and non-polar analytes. The analysis of bisphenol A from extracts of recycled paper demonstrates the use of this ion source for real samples. Quantification was possible by the use of a deuterated internal standard that was added to the papers before extraction. Here atmospheric pressure chemical ionization leads to bad results due to ion suppression, whereas atmospheric pressure photoionization shows results that fit to literature values.