1. Joint Mass Spectrometry Centre, Chair of Analytical Chemistry, University of Rostock, Dr. Lorenz-Weg 2, 18059 Rostock, Germany
2. Joint Mass Spectrometry Centre, Comprehensive Molecular Analytics, Helmholtz Center Munich German Research Center for Environmental Health, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
3. ASG Analytik-Service Gesellschaft mbH, Trentiner Ring 30, 86356 Neusäss, Germany