Journal article
Electrolyte-free Amperometric Immunosensor using a Dendritic Nanotip
RSC advances, Vol.3(13), pp.4281-4287
2013
Handle:
https://hdl.handle.net/2376/117463
PMCID: PMC3622275
PMID: 23585927
Abstract
Electric detection using a nanocomponent may lead to platforms for rapid and simple biosensing. Sensors composed of nanotips or nanodots have been described for highly sensitive amperometry enabled by confined geometry. However, both fabrication and use of nanostructured sensors remain challenging. This paper describes a dendritic nanotip used as an amperometric biosensor for highly sensitive detection of target bacteria. A dendritic nanotip is structured by Si nanowires coated with single-walled carbon nanotubes (SWCNTs) for generation of a high electric field. For reliable measurement using the dendritic structure, Si nanowires were uniformly fabricated by ultraviolet (UV) lithography and etching. The dendritic structure effectively increased the electric current density near the terminal end of the nanotip according to numerical computation. The electrical characteristics of a dendritic nanotip with additional protein layers was studied by cyclic voltammetry and
I–V
measurement in deionized (DI) water. When the target bacteria dielectrophoretically captured onto a nanotip were bound with fluorescence antibodies, the electric current through DI water decreased. Measurement results were consistent with fluorescence- and electron microscopy. The sensitivity of the amperometry was 10 cfu/sample volume (10
3
cfu/mL), which was equivalent to the more laborious fluorescence measurement method. The simple configuration of a dendritic nanotip can potentially offer an electrolyte-free detection platform for sensitive and rapid biosensors.
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Details
- Title
- Electrolyte-free Amperometric Immunosensor using a Dendritic Nanotip
- Creators
- Jong-Hoon Kim - Department of Mechanical Engineering, University of Washington, Seattle, WA, USAMorgan Hiraiwa - Department of Mechanical Engineering, University of Washington, Seattle, WA, USAHyun-Boo Lee - Department of Mechanical Engineering, University of Washington, Seattle, WA, USAKyong-Hoon Lee - NanoFacture, Inc., P.O. Box 52651, Bellevue, WA, USAGerard A Cangelosi - Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USAJae-Hyun Chung - Department of Mechanical Engineering, University of Washington, Seattle, WA, USA
- Publication Details
- RSC advances, Vol.3(13), pp.4281-4287
- Academic Unit
- Engineering and Computer Science (VANC), School of
- Identifiers
- 99900547929901842
- Language
- English
- Resource Type
- Journal article