1. Instituto de Microelectrónica de Barcelona; IMB-CNM (CSIC); Universitat Autónoma de Barcelona; Barcelona; Spain
2. Alphasip S. L.; Zaragoza; Spain
3. Departamento de Química Analítica; Facultad de CC. Químicas; Universidad Complutense de Madrid; Madrid; Spain
4. Biomedical Diagnostics Institute; National Centre for Sensor Research; School of Physical Sciences; Dublin City University; Dublin; Ireland