Chemiresistive biosensors based on carbon nanotubes for label-free detection of DNA sequences derived from avian influenza virus H5N1
Y. Fu, V. Romay, Y. Liu, B. Ibarlucea, L. Baraban, V. Khavrus, S. Oswald, A. Bachmatiuk, I. Ibrahim, M. Rümmeli, T. Gemming, V. Bezugly, and G. Cuniberti
Sensors and Actuators B: Chemical 249, 691 (2017)
We developed chemiresistor-type biosensors based on carbon nanotubes for highly efficient and fast detection of avian influenza virus (AIV) subtype H5N1 DNA sequences. Semiconducting single-walled carbon nanotubes (sc-SWCNTs) or nitrogen-doped multi-walled carbon nanotubes (N-MWCNTs) were used as two alternative active sensing elements, and their sensitivity to different concentrations of DNA target were compared. In these sensors long nanotubes (>5†µm) were placed between interdigitated metal electrodes so that individual nanotubes connect the electrodes. The nanotubes were functionalized with DNA probe sequences non-covalently attached to the sidewalls. Such functionalized-nanotube sensors could reliably detect complementary DNA target sequences of the AIV H5N1 with concentration ranging from 2†pM to 2†nM in 15†min and at room temperature. Our nanotube-based biosensors are small, flexible, disposable and easy-to-fabricate that makes them promising for point-of-care applications and clinical diagnostics.