Early detection of diseases is a key factor for their rapid and efficient treatment, and this is even more crucial for pathologies with high rate of mortality such as cancers and neurodegenerative diseases.
In the majority of cases, diagnosis of such pathologies occurs in late stages when patients consult their physician due to the appearance of symptoms.
A central societal and medical challenge in the field is to develop technologies that would safely and non-invasively detect pathologies such as cancers as easily as the blood pressure test that is systematically performed during medical consultations.
Breath is an attractive sample since it is non-invasive, simple to collect repetitively and more importantly at least 17 pathologies were identified as producing detectable volatile biomarkers (Konvalina and Haick, 2014).
With the development of micro- and nano-electronic systems, the concept of electronic noses (e-noses) emerged for the detection of volatile organic compounds (VOCs) through electrical, gravimetric or optical signals in handheld devices. Different technologies of e-noses were developed and the most advanced technologies are based on "chemiresistors" that recognized VOCs by physico-chemical interactions.
Unexpectedly, detection of diseases such as cancers appeared to be more complex because for most diseases, not a single biomarker is sufficient to obtain an accurate diagnosis. Therefore, the technological challenge is to simultaneously and quantitatively detect several biomarkers with high sensitivity, high specificity and without being affected by confounding factors like humidity, temperature and pressure. While the physico-chemical biosensors are highly sensitive and suitable for gas analysis, they are also poorly specific, weakly versatile and highly sensitive to confounding factors.
In order to develop a new generation of e-noses that overcomes these technological obstacles and complement the current range of biosensors, the NANOZ-ONIC project aimed to develop technologies toward the design of bio-inspired e-noses that mimics the natural olfactory systems. The concept was based on two cutting-edge technologies: 1) artificial receptor-ion channel proteins that generate an electrical signal when a receptor recognizes a specific compound; and 2) the highly sensitive and miniaturized single-wall carbon nanotube field-effect transistors (swCNT-FET) that are interfaced with the artificial receptor-ion channel proteins. The project was performed by international leading experts in these technologies working in the French CNRS Institute and the Korean Seoul National University with the key support from ERC.
The ambitious objective of the 5-year project was to design a library of olfactory biosensors based on olfactory receptors which would provide the required high specificity and versatility for diagnosing new pathologies by breath analysis. The biosensors were interfaced into the swCNT-FET nano-electronic system for the simultaneous and extremely sensitive detection of volatile compounds. The long term objective of the project is to create a hand-held device able to detect volatile biomarkers from exhaled breath samples and alert to the presence of diseases in early asymptomatic stages.
References:
Dorman et al. (2017) Vet Med. 8, 69-76.
Fischer-Tenhagen et al. (2018) Front Vet Sci 5, 52.
Konvalina and Haick (2014) Acc Chem Res 47, 66-76.
