1. Department of Chemistry, Laboratory of Analytical Chemistry; University of Konstanz; 78457 Konstanz Germany
2. Faculty of Chemistry; “Al. I. Cuza” University of Iasi; 11 Carol I Bd Iasi 700506 Romania
3. Steinbeis Centre for Biopolymer Analysis and Biomedical Mass Spectrometry; 65428 Rüsselsheim am Main Germany
4. Proteome Center, Institute of Immunology; University of Rostock; Rostock Germany
5. Chromsystems Instruments & Chemicals GmbH; 82166 Gräfelfing Germany
6. Department of Chemistry & Chemical Biology; Northeastern University; Boston MA USA