Oct. 13, 2005--University of Delaware researchers are opening a new front
in the war on cancer, bringing to bear new nanotechnologies for cancer detection
and treatment and introducing a unique nanobomb that can literally blow up
breast cancer tumors.
Balaji Panchapakesan, assistant professor of electrical
and computer engineering at UD, has recently reported
on the discoveries in the journals NanoBiotechnology and Oncology
Issues .
He is the lead investigator for a team that includes
Eric Wickstrom, professor of biochemistry and molecular
biology at Thomas Jefferson University in Philadelphia
and his student Greg Cesarone, and UD graduate students
Shaoxin Lu, Kousik Sivakumar and postdoctoral researcher
Kasif Teker.
Panchapakesan said this is basic research in the
very early stages of inquiry and that it would take
extensive testing and years of clinical trials before
the nanobombs could actually be used in medical applications
to treat human beings.
“Make no mistake, we are focused on eradicating
cancer,” Panchapakesan said, explaining that the
nanobombs are the result of work over the past two
years with carbon nanotubes, which are atoms of carbon
arranged in tubular form.
Originally, he said, the research team was looking
at the use of the carbon nanotubes as drug delivery
vehicles. Because they are smaller than the size
of a single cell, the nanotubes can provide for the
highly selective injection of drugs into individual
cells.
As they undertook various experiments, however,
the team made a startling discovery. “When you put
the atoms in different shapes and forms, they take
on different properties at the nanoscale,” Panchapakesan
said. “We were experimenting with the molecules and
considering optical and thermal properties, and found
we could trigger microscopic explosions of nanotubes
in wide variety of conditions.”
Explosions in air of loosely packed nanotubes have
been seen before in an oxygen environment, creating
ignition. However, the work reported by Panchapakesan
uses the localized thermal energy imbalance to set
off explosions that are intrinsic in nature.
Panchapakesan said the nanobombs are just that,
tiny bombs on the nanoscale. “They work almost like
cluster bombs,” he said. “Once they are exposed to
light and the resulting heat, they start exploding
one after another.”
The bombs are created by bundling the carbon nanotubes.
With a single nanotube, the heat generated by the
light is dissipated by surrounding air. In bundles,
the heat cannot dissipate as quickly and the result
is “an explosion on the nanoscale,” Panchapakesan
said.
When the UD researchers saw the explosions, they
realized it might be possible to use the microscopic
bombs to kill cancer cells. They recreated the explosions
in solutions including water, phosphate and salt,
which meant the nanobombs could be used in the human
body. In fact the explosions were more dramatic in
saline solutions, Panchapakesan said.
“The nanobomb is very selective, very localized
and minimally invasive,” Panchapakesan said. “It
might cause what I would call nanopain, like a pin
prick.”
He believes the nanobomb holds great promise as
a therapeutic agent for killing cancer cells, with
particular emphasis on breast cancer cells, because
its shockwave kills the cancerous cells as well as
the biological pathways that carry instructions to
generate additional cancerous cells and the small
veins that nourish the diseased cells. Also, it can
be spread over a wide area to create structural damage
to the cancer cells that are close by.
The nanobombs are superior to a variety of current
treatments because they are powerful, selective,
non-invasive, nontoxic and can incorporate current
technology, including microsurgery
|
