Biomedical Engineering Reference
In-Depth Information
4
Impedimetric DNA Biosensors
Based on Nanomaterials
Manel del Valle*
,1
and Alessandra Bonanni
2
1
Sensors and Biosensors Group, Chemistry Department, Autonomous University
of Barcelona, Barcelona, Spain
2
Division of Chemistry and Biological Chemistry, School of Physical and
Mathematical Sciences, Nanyang Technological University, Singapore
Abstract
h is chapter describes variants of DNA sensors (genosensors) that employ elec-
trochemical impedance signal for detecting a target DNA. In this way, the clinical
diagnostic-related sought gene or gene variant can be very simply detected with
an electrically addressable device, and potentially, without the use of any label.
Existing variants for measuring and the dif erent formats for the assay are pre-
sented. To improve the performance of these devices, current nanobiotechnology
utilizes nanocomponents, either at the transducer level or integrated in the proce-
dure itself, to improve the detection or to amplify the signal. Carbon nanotubes and
nanowires, graphene or gold nanoparticles can be used to produce or to modify
transducers, fostering their electrical characteristics, or helping in the immobiliza-
tion of the recognition element. Metal nanoparticles or even quantum dots may be
used to improve signal-to-noise ratio. h e chapter ends by summarizing existing
applications related to clinical diagnostics and discussing the latest trends.
1
Keywords:
DNA biosensor, genosensor, carbon nanotube, gold nanoparticles,
quantum dots, electrochemical impedance spectroscopy
Some of the information presented has been adapted from chapter 9. Impedimetric
DNA Sensing Employing Nanomaterials (Manel del Valle and Alessandra Bonanni), in
Biomaterials and Diagnostic Devices, Ashutosh Tiwari, Murugan Ramalingam, isatoshi
Kobayashi and P.F. Turner (eds.).
