EGAS41 - Swansea University

41 st EGAS CP 52 Gdańsk 2009
Novel nanosensors for environmental and medical sensing using
ultra-sensitive mass, chemical and biological detection methods
based on carbon nanostructures
I. Kierk ∗ , M. Bockrath
Department of Engineering & Applied Science California Institute of Technology,
1200 E. California Blvd., Pasadena, CA USA
∗ Corresponding author: isabella@caltech.edu
Nanotechnology has emerged as one of the most active facets of scientific research and
technology development. In our talk we will discuss two areas were the fundamental
research could be used for environmental and medical applications.
Developing field-capable sensors that can be used to characterize and assist in the
remediation of environmentally polluted sites is vital. To properly understand, monitor
and characterize the impact of nanotechnology on the environment, ultra-sensitive sensors
that outperform the current state-of-the-art are required. For instance, to monitor the
effect of nanoparticles, sensors that are capable of detecting miniscule amount of nanoparticles
will be necessary. To this end, we intend to fabricate and develop ultra-sensitive
sensors based on suspended carbon nanotubes and graphene. These devices have a resonant
frequency that depends on the total mass of the suspended part; thus the adsorption
of molecules can be detected through shifts in the resonant frequency. Since both carbon
nanotubes and graphene are extremely light-weight, they can be exceedingly sensitive,
e.g. suspended nanotubes have been demonstrated to detect the arrival of single atoms
[1, 2]. In our recent work [1], we used individual single-walled carbon nanotube resonators
to detect and weigh adsorbed atoms. Our work also constitutes the first demonstration of
using nanotubes’ single-electron transistor properties to self-detect the nanotube vibrations,
which yields greatly enhanced displacement sensitivity. We expect to develop mass
sensors and optimize and characterize their performance.
In the second part of our talk we will discuss using biosensors based on carbon nanotube
and graphene devices for the early detection of melanoma and other cancers.
Melanoma (the 5 th and 6 th most common cancer in Caucasian males and females,
respectively), is the most severe form of skin cancer, which is often fatal if recognized
in its advanced stage. Clinically, it is very difficult to correctly differentiate nevi with
atypical features or dysplastic nevi, and nevi of special sites from melanoma. Clearly,
new, more powerful, less invasive, time consuming and expensive tools are needed for an
early and accurate detection of melanoma. In order to address this need, we will discuss a
development of a new set of tools, namely, carbon-nanotube and graphene based biosensors
for the early and accurate detection of melanoma. Once successful, we will modify and
apply this new technology to early and accurately detect other types of cancer.
References
[1] H.-Y. Chiu, P. Hung, H.W.C. Postma, M. Bockrath, Nano Letters 8, 4342 (2008)
[2] K. Jensen, K. Kim, A. Zettl, Nat. Nano. 3, 533 (2008)
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