LabAutomation 2006 - SLAS

Where Laboratory Technologies Emerge and Merge
9:30 am Wednesday, January 25, 2006 Track 2: Micro- and Nanotechnologies Room: Pasadena
Wyndham Palm Springs Hotel
Paolo Fortina
Thomas Jefferson University
Philadelphia, Pennsylvania
paolo.fortina@jefferson.edu
Nanotechnology Enabled Direct SNP/Mutation Detection
Key objectives for innovation in SNP profiling would include assays that do not require locus-specific amplification, facilitate multiplexed
testing, exhibit increased sensitivity with new and more cost-effective scanning methods or ultimately with direct visual detection. In
addition, there are a limited number, if any, of assays, which measure genetic variation present in one part in a million without use of
locus-specific PCR. Gold nanoparticles of different shape and composition are emerging as important reagents for nucleic acid assays,
as they have a number of intriguing properties that facilitate multiplexing, improve on sensitivity in the zmole range and allow naked eye
detection, when appropriate strategies of target preparation are employed. These innovations may ultimately propel routine cancer gene
analysis to the forefront of clinical testing as low cost assays, not requiring costly scanner, and being exportable and implementable in
developing countries where genetic testing is required.
10:00 am Wednesday, January 25, 2006 Track 2: Micro- and Nanotechnologies Room: Pasadena
Wyndham Palm Springs Hotel
Angelika Niemz
Co-Author(s)
Keck Graduate Institute
Eric Tan
Claremont, California
Krisanu Bandyopadhyay
aniemz@kgi.edu
Sharon Byers
Karen Ellison
Ekaterina Kniazeva
Electronic DNA Detection on Semiconductor Surfaces
We are developing biosensors for electronic DNA detection on silicon surfaces, which will enable direct interfacing with silicon based
microelectronic devices. DNA hybridization to a probe-functionalized Si/SiOx interface leads to a change in surface charge density
based on the intrinsic negative charge of DNA. This electrolyte-oxide-semiconductor (EOS) interface behaves similar to a metal-oxidesemiconductor
(MOS) device. Therefore, the change in surface charge density causes a shift in the semiconductor’s impedance response
through the field effect. To increase sensitivity, we are combining impedance-based DNA detection with a novel isothermal amplification
method for short oligonucleotides (EXPAR). We are further investigating how co-immobilizing DNA functionalized gold nanospheres along
with target DNA affects the observed shift in impedance response. These sensors are expected to facilitate rapid, specific, and sensitive
detection of clinical pathogens and biothreat agents.
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