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arXiv · 1601.01299

Detection of DNA and Poly-L-Lysine using CVD Graphene-channel FET Biosensors

Aniket Kakatkar·T. S. Abhilash·Roberto De Alba·Jeevak M Parpia·Harold G Craighead
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Abstract

A graphene channel field-effect biosensor is demonstrated for detecting the binding of double-stranded DNA and poly-l-lysine. Sensors consist of CVD graphene transferred using a clean, etchant-free transfer method. The presence of DNA and poly-l-lysine are detected by the conductance change of the graphene transistor. A readily measured shift in the Dirac Voltage (the voltage at which the graphenes resistance peaks) is observed after the graphene channel is exposed to solutions containing DNA or poly-l-lysine. The Dirac voltage shift is attributed to the binding/unbinding of charged molecules on the graphene surface. The polarity of the response changes to positive direction with poly-l-lysine and negative direction with DNA. This response results in detection limits of 8 pM for 48.5 kbp DNA and 11 pM for poly-l-lysine. The biosensors are easy to fabricate, reusable and are promising as sensors of a wide variety of charged biomolecules

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Aniket Kakatkar, T. S. Abhilash, Roberto De Alba, Jeevak M Parpia, Harold G Craighead. 2016-01-06. Detection of DNA and Poly-L-Lysine using CVD Graphene-channel FET Biosensors. https://doi.org/10.1088/0957-4484%2F26%2F12%2F125502

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