1. Centro Studi e Documentazione sulla Sensoristica, University of Rome TorVergata, via del Politecnico, 1 00133 Roma, Italy
2. Unit of Electronics for Sensor Systems, Faculty of Engineering, University Campus Bio-Medico di Roma, Via Alvaro del Portillo 21, 00128 Roma, Italy
3. Department of Physics, Chemistry and Biology, Linkoping University, 581 83 Linköping, Sweden