PORTLAND, Ore.óCarbon-based platforms outperform existing silicon-nitride based systems, according to a University of Pennsylvania team that is working on a system which automates DNA sequencing. With its carbon-based detectors, the team has been able to sense the electronic signatures of DNA strands with integrated graphene nanopores.
The graphene-based detector was fabricated at the University of Pennsylvania using chemical vapor deposition to grow flakes of graphene in which they drilled nanoscale pores with the electron beam of a transmission electron microscope.
The researchers were able to demonstrate that individual DNA strands could be coaxed into threading through the tiny graphene nanopores with electric fields. The process, called translocation, detects the components of a DNA strand (called bases) by sensing them with tiny electrodes as they glide through the graphene pore. Each DNA base, according to the researchers, can be distinguished by virtue of conducting with a slightly different current.
University of Pennsylvania researchers developed
a carbon-based, nanoscale platform to electrically detect single DNA molecules
by using electric fields to push tiny DNA strands through atomically-thin
graphene nanopores that ultimately may sequence DNA bases by their unique
Photo credit: Robert Johnson.
The carbon-based platform was found to significantly
boost the signal coming from the translocation electrodes, compared to
existing silicon nitride detectors.
Funding for the research was provided by the National Institutes of
Health, the U.S. Department of Defense, Army Research Office, Penn
Genome Frontiers Institute, Nano-Bio Interface Center at Penn,
Nanotechnology Institute of the Commonwealth of Pennsylvania and the
Pennsylvania Department of Health.
Don't know the current state of, but the base pair detection is key especially if speed comes to the table. I am M.D. and RF Engineer and am familiar with the existing equipment in general, which is doing auto sequencing since the Human Genome Project started. One of the primary scientists in the HGP actually designed the equipment which is currently used, as best as I remember.
We are certainly headed for a hand held device to provide DNA ID in the field one day..I think. Electro-phoresis..is well known..and if its a matter of fine tuning an amplifiers sensibility..IBM may be real close.
It still bowls me over to see how far we have come with DNA since Dr's Watson and Crick.
just 4 little base pairs...repeated over and over again in a ballet of a million steps..or so.
Yet we are all so unique..sometimes due to just a one base pair "oops" along the way.
Any medical electronics experts out there know the state of personal DNA sequencing? I know that IBM has an effort to pull DNA strands through a nanopore and use a transistor to sense each base electrically as they pass through the pore. That sounds similar to this research at the University of Pennsylvania--which makes me think that sequencing an individual's DNA--which is IBM's professed aim--might be underway at other electronics labs too. Any medical electronics experts out there know the state of personal DNA sequencing?