4.8 Article

Flexure-FET biosensor to break the fundamental sensitivity limits of nanobiosensors using nonlinear electromechanical coupling

Publisher

NATL ACAD SCIENCES
DOI: 10.1073/pnas.1203749109

Keywords

label-free detection; genome sequencing; cantilever; spring-softening; critical-point sensors

Funding

  1. National Institutes of Health (NIH) [R01-CA20003]
  2. Materials, Structures and Devices (MSD) Focus Center
  3. PRISM center

Ask authors/readers for more resources

In this article, we propose a Flexure-FET (flexure sensitive field effect transistor) ultrasensitive biosensor that utilizes the nonlinear electromechanical coupling to overcome the fundamental sensitivity limits of classical electrical or mechanical nanoscale biosensors. The stiffness of the suspended gate of Flexure-FET changes with the capture of the target biomolecules, and the corresponding change in the gate shape or deflection is reflected in the drain current of FET. The Flexure-FET is configured to operate such that the gate is biased near pull-in instability, and the FET-channel is biased in the subthreshold regime. In this coupled nonlinear operating mode, the sensitivity (S) of Flexure-FET with respect to the captured molecule density (N-s) is shown to be exponentially higher than that of any other electrical or mechanical biosensor. In other words, while S-Flexure similar to e((gamma 1 root Ns-gamma 2Ns)), classical electrical or mechanical biosensors are limited to S-classical similar to gamma N-3(S) or gamma(4) ln(N-S), where gamma(i) are sensor-specific constants. In addition, the proposed sensor can detect both charged and charge-neutral biomolecules, without requiring a reference electrode or any sophisticated instrumentation, making it a potential candidate for various low-cost, point-of-care applications.

Authors

I am an author on this paper
Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.8
Not enough ratings

Secondary Ratings

Novelty
-
Significance
-
Scientific rigor
-
Rate this paper

Recommended

No Data Available
No Data Available