1. Paperdrop Diagnostics S.L., MRB, Campus UAB, 08193 Bellaterra, Spain
2. Nanobioelectronics and Biosensors Group, Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC, 08193 Barcelona, Spain
3. The Barcelona Institute of Science and Technology (BIST), Campus UAB, 08036 Bellaterra, Barcelona Spain
4. ICREA, Institució Catalana de Recerca i Estudis Avançats, Pg. Lluis Companys 23, 08010 Barcelona, Spain