“…Among the 26 articles found in literature reporting on CNTs-based electronic noses for breathomic applications, 20 of them present electronic noses completely based on CNTs-sensors [ 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 ], while 6 papers report on electronic noses that host both CNTs-sensors and NPs-based sensors [ 54 , 55 , 56 , 57 , 58 , 59 ]. All the electronic noses included in the latter group have been tested on the exhaled breath of patients, while only four electronic noses of the former group have been exposed to human breath [ 50 , 51 , 52 , 53 ], whereas 13 arrays have been tested only to target gases [ 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 ]. Tests on simulated exhaled breath have been performed by two electronic noses [ 47 , 48 ] and one array has been exposed to the breath of rats [ ...…”