Journal
NANO LETTERS
Volume 11, Issue 9, Pages 3739-3743Publisher
AMER CHEMICAL SOC
DOI: 10.1021/nl201781q
Keywords
Debye screening; carbon nanotube; single-molecule detection; field-effect sensor; DNA; microfluidics
Categories
Funding
- NHGRI NIH HHS [R33 HG003089] Funding Source: Medline
Ask authors/readers for more resources
Point-functionalized carbon nanotube field-effect transistors can serve as highly sensitive detectors for biomolecules. With a probe molecule covalently bound to a defect in the nanotube sidewall, two-level random telegraph noise (RTN) in the conductance of the device is observed as a result of a charged target biomolecule binding and unbinding at the defect site. Charge in proximity to the defect modulates the potential (and transmission) of the conductance-limiting barrier created by the defect. In this Letter, we study how these single-molecule electronic sensors are affected by ionic screening. Both charge in proximity to the defect site and buffer concentration are found to affect RTN amplitude in a manner that follows from simple Debye length considerations. RTN amplitude is also dependent on the potential of the electrolyte gate as applied to the reference electrode; at high enough gate potentials, the target DNA is completely repelled and RTN is suppressed.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available