The use of sensors and sensing devices in breath analysis is a very recent achievement in medicine. In this study, a portable pre-industrial device capable of monitoring NO in lung exhaled in respect to the ATS/ERS guidelines was designed and manufactured. The proposed equipment, called NOESIS, involved the use of a conductive polymer doped with nanofibres of an electrospun metal oxide, and was characterised by high sensing features, low power consumption, cost-effectiveness and cheapness. The properties of the sensor and the strategies utilised to achieve such results in that device are here reported and discussed.