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Title: Ion detection in a DNA nanopore FET device
Abstract An ion detection device that combines a DNA-origami nanopore and a field-effect transistor (FET) was designed and modeled to determine sensitivity of the nanodevice to the local cellular environment. Such devices could be integrated into a live cell, creating an abiotic-biotic interface integrated with semiconductor electronics. A continuum model is used to describe the behavior of ions in an electrolyte solution. The drift-diffusion equations are employed to model the ion distribution, taking into account the electric fields and concentration gradients. This was matched to the results from electric double layer theory to verify applicability of the model to a bio-sensing environment. The FET device combined with the nanopore is shown to have high sensitivity to ion concentration and nanopore geometry, with the electrical double layer behavior governing the device characteristics. A logarithmic relationship was found between ion concentration and a single FET current, generating up to 200 nA of current difference with a small applied bias.  more » « less
Award ID(s):
2027165
PAR ID:
10563025
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
iopscience
Date Published:
Journal Name:
Nanotechnology
Volume:
35
Issue:
32
ISSN:
0957-4484
Page Range / eLocation ID:
325202
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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