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bioRxiv · 10.1101/2023.08.11.552535

Variable Gain DNA Nanostructure Charge Amplifiers for Biosensing

Majikes, J. M.·Cho, S.·Cleveland, T. E.·Liddle, J. A.·Balijepalli, A.
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Abstract

Electronic measurements of engineered nanostructures comprised solely of DNA (DNA nanostructures) enable new signal conditioning modalities in biosensing. Here, we demonstrate how DNA nanostructures that alter their conformation upon binding a nucleic acid analyte drastically, and reversibly, amplify the measured electrochemical signal. This amplification was controlled by the applied electrical field to achieve a response {approx} 2x104 times greater than that measured from DNA hybridization. Because the amplification is independent of the interaction between the analyte and the DNA nanostructure, our approach provides a platform for tuning the response of the system for high performance that is agnostic of the end application. These molecularly precise self-assembled DNA nanostructures when paired with scalable electronic readout can therefore lead the way to highly sensitive multiplexed biosensing.

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Majikes, J. M., Cho, S., Cleveland, T. E., Liddle, J. A., Balijepalli, A.. 2023-08-14. Variable Gain DNA Nanostructure Charge Amplifiers for Biosensing. https://doi.org/10.1101/2023.08.11.552535

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