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bioRxiv · 10.1101/2021.01.19.427256

An all-solid-state heterojunction oxide transistor for the rapid detection of biomolecules and SARS-CoV-2 spike S1 protein

Lin, Y.-H.·Han, Y.·Sharma, A.·AlGhamdi, W. S.·Liu, C.-H.·Chang, T.-H.·Xiao, X.-W.·Seitkhan, A.·Mottram, A. D.·Pattanasattayavong, P.·Faber, H.·Heeney, M.·Anthopoulos, T. D.
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Abstract

Solid-state transistor sensors that can detect biomolecules in real time are highly attractive for emerging bioanalytical applications. However, combining cost-effective manufacturing with high sensitivity, specificity and fast sensing response, remains challenging. Here we develop low-temperature solution-processed In2O3/ZnO heterojunction transistors featuring a geometrically engineered tri-channel architecture for rapid real-time detection of different biomolecules. The sensor combines a high electron mobility channel, attributed to the quasi-two-dimensional electron gas (q2DEG) at the buried In2O3/ZnO heterointerface, in close proximity to a sensing surface featuring tethered analyte receptors. The unusual tri-channel design enables strong coupling between the buried q2DEG and the minute electronic perturbations occurring during receptor-analyte interactions allowing for robust, real-time detection of biomolecules down to attomolar (aM) concentrations. By functionalizing the tri-channel surface with SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2) antibody receptors, we demonstrate real-time detection of the SARS-CoV-2 spike S1 protein down to attomolar concentrations in under two minutes.

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Lin, Y.-H., Han, Y., Sharma, A., AlGhamdi, W. S., Liu, C.-H., Chang, T.-H., Xiao, X.-W., Seitkhan, A., Mottram, A. D., Pattanasattayavong, P., Faber, H., Heeney, M., Anthopoulos, T. D.. 2021-01-19. An all-solid-state heterojunction oxide transistor for the rapid detection of biomolecules and SARS-CoV-2 spike S1 protein. https://doi.org/10.1101/2021.01.19.427256

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