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bioRxiv · 10.1101/2024.12.11.627986

A Label-free Nanowell-based Impedance Sensor for Ten-minute SARS-CoV-2 Detection

Meng, Z.·White, L.·Xie, P.·Mahmoodi, S. R.·Karapiperis, A.·Lin, H.·Drazer, G.·Javanmard, M.·DeMauro, E. P.
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Abstract

This work explores label-free biosensing as an effective method for biomolecular analysis, ensuring the preservation of native conformation and biological activity. The focus is on a novel electronic biosensing platform utilizing micro-fabricated nanowell-based impedance sensors, offering rapid, point-of-care diagnosis for SARS-CoV-2 (COVID-19) detection. The nanowell sensor, constructed on a silica substrate through a series of microfabrication processes including deposition, patterning, and etching, features a 5x5 well array functionalized with antibodies. Real-time impedance changes within the nanowell array enable diagnostic results within ten minutes using small sample volumes (<5 {micro}L). The research includes assays for SARS-CoV-2 spike proteins in Phosphate-buffered saline (PBS) and artificial saliva buffers to mimic real human SARS-CoV-2 samples, covering a wide range of concentrations. The sensor exhibits a detection limit of 0.2 ng/mL (1.5 pM) for spike proteins. Middle East Respiratory Syndrome (MERS-CoV) spike proteins are differentiated from SARS-CoV-2 spike proteins, demonstrating specificity. TOC Graphic O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=113 SRC="FIGDIR/small/627986v1_ufig1.gif" ALT="Figure 1"> View larger version (58K): org.highwire.dtl.DTLVardef@1a9f2a7org.highwire.dtl.DTLVardef@79d5acorg.highwire.dtl.DTLVardef@bb1bc1org.highwire.dtl.DTLVardef@1b5098_HPS_FORMAT_FIGEXP M_FIG C_FIG

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Meng, Z., White, L., Xie, P., Mahmoodi, S. R., Karapiperis, A., Lin, H., Drazer, G., Javanmard, M., DeMauro, E. P.. 2024-12-12. A Label-free Nanowell-based Impedance Sensor for Ten-minute SARS-CoV-2 Detection. https://doi.org/10.1101/2024.12.11.627986

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