1. Institute of Biomedical Engineering and Nanotechnologies Riga Technical University Kipsalas Str. 6B LV-1048 Riga Latvia
2. Department of Analysis of Functional Materials Institute of Physics of the Czech Academy of Sciences Na Slovance 2 182 21 Prague Czech Republic
3. Department of Physics and Measurements University of Chemistry and Technology Technická 5 166 28 Prague Czech Republic
4. Institute of Chemical Physics University of Latvia Jelgavas Str.1 LV-1004 Riga Latvia