Sensing at the Zeptomolar Concentration Level with Large Area Bioelectronic Interfaces

Nanosized interfaces have been the favoured route to single-molecule detections so far. However, because of the so-called <i>diffusion-barrier</i> issue, such <i>near-field</i> approaches, encompassing nano-wire transistors but also nanopores and many others, are, not able to detect at concentrations lower than nanomolar. Bioelectronic field-effect transistors endowed with l<i>arge-area</i> (mm² wide) detecting interfaces, are perceived as unsuited too, because the footprint of a single molecule is negligible when compared to a large detecting interface. <i>This is challenging as it would be like detecting a single droplet impacting on a kilometer-wide surface</i>. However, many different groups have published data proving that field-effect large-area biosensors can detect at limit-of-detection of femtomolar and below.<br/>Moreover, these single-molecule large-area bioelectronic based technologies can involve small readers, are fast, easy to operate directly in the fluid to be analyzed, and the electronic outputs are already in a convenient digital form so that an easy transfer to app is possible. Moreover, they can be fabricated by cost-effective technologies including printing and other direct-writing processes. Hence, ultrasensitive large area bioelectronic sensors are likely to have a bright future in healthcare. This lecture will give an overview of this field, discussing device architectures, materials used, and target analytes that can be selectively detected as well as the sensing mechanisms.<br/><b>Biblio</b>:<br/>- The 2021 flexible and printed electronics roadmap, Yvan Bonnassieux <i>at al.</i> Flexible and Printed Electronics, volume 6 (2), article number: 023001 (2022) DOI: 10.1088/2058-8585/abf986<br/>- Electrolyte-gated transistors for enhanced performance bioelectronics, Fabrizio Torricelli <i>et al. </i><br/>Nature Reviews Methods Primers, volume 1, Article number: 66 (2021) DOI:10.1038/s43586-021-00065-8