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On the origin of enhanced sensitivity in nanoscale FET-based biosensors.

ABSTRACT: Electrostatic counter ion screening is a phenomenon that is detrimental to the sensitivity of charge detection in electrolytic environments, such as in field-effect transistor-based biosensors. Using simple analytical arguments, we show that electrostatic screening is weaker in the vicinity of concave curved surfaces, and stronger in the vicinity of convex surfaces. We use this insight to show, using numerical simulations, that the enhanced sensitivity observed in nanoscale biosensors is due to binding of biomolecules in concave corners where screening is reduced. We show that the traditional argument, that increased surface area-to-volume ratio for nanoscale sensors is responsible for their increased sensitivity, is incorrect.

SUBMITTER: Shoorideh K

PROVIDER: S-EPMC3986196 | biostudies-literature | 2014 Apr

REPOSITORIES: biostudies-literature

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On the origin of enhanced sensitivity in nanoscale FET-based biosensors.

Shoorideh Kaveh K Chui Chi On CO

Proceedings of the National Academy of Sciences of the United States of America 20140325 14

Electrostatic counter ion screening is a phenomenon that is detrimental to the sensitivity of charge detection in electrolytic environments, such as in field-effect transistor-based biosensors. Using simple analytical arguments, we show that electrostatic screening is weaker in the vicinity of concave curved surfaces, and stronger in the vicinity of convex surfaces. We use this insight to show, using numerical simulations, that the enhanced sensitivity observed in nanoscale biosensors is due to ...[more]

PMID: 24706861

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