If Vicki Grassian
were to pop open a vial of ultraminiature iron
oxide particles, the stuff would escape in a
puff of dust and spread through the air. It’s
hard to think a little dust could make much difference.
But Grassian, professor of chemistry in the College
of Liberal Arts and Sciences, is one of at least
several dozen scientists on the University of
Iowa campus intensely interested in looking into
a strange world of almost unimaginably small
things that could have gigantic effects.
Grassian is studying nanoscience—science
that takes place between one and 100 nanometers
(one nanometer is one-billionth of a meter;
10 nanometers are 1,000 times smaller than
the diameter of a human hair). It’s the
same small science that gives us khaki pants
advertised to knock out stains and wrinkles
and that inspires researchers to find ways
to boost the efficiency of our cars and change
the way doctors treat cancer.
“We are only beginning to see the possibilities
nanoscience can show us,” says Grassian,
who holds a joint appointment as professor
of chemical and biochemical engineering in
the College of Engineering.
Scientists at The University of Iowa are exploring
possibilities that could change every aspect
of daily life, from medical treatment and environmental
pollution to computer circuitry. Nanoscience
research is taking place in dozens of the University’s
departments and programs, including biology,
chemistry, dentistry, engineering, mathematics,
pharmacy, physics, and English. The research
ranges from the practical to the sublime, covering
environmental science, computational chemistry
and molecular modeling, semiconductor devices,
pharmaceutics, and much more—even science
fiction.
Size
Matters
Scientists at The University of Iowa are interested
in nanoscience because materials change fundamentally
when they are reduced to the nano level. Zeolite
crystals, for example, ordinarily (that is,
at the micron level or above) look like a white
powder, but when the crystal size is cut down
to 20 nanometers, a transparent film forms,
making it good for optical applications, according
to Sarah Larsen, associate professor of chemistry.
 |
| A
scanning electron microscope in the UI
Central Microscopy Research Facility
produced these images of rectangular
fibers formed by the self-assembly of
the nanocrystalline silicalite. |
“Suddenly, the size dictates the properties,” says
Larsen, who shows her undergraduates how to
make solar cells from the nanosized inorganic
materials they find in raspberry juice. “You
can make old materials do new stuff.”
In the old days, scientists thought the properties
of a material depended only on composition
and phase (solid, liquid, or gas), Larsen says.
With the new knowledge that size also matters,
she can investigate novel chemical properties
of nanocrystals to speed the absorbency and
breakdown of toxic wastes, and colleague Ned
Bowden, assistant professor of chemistry, can
study how nanorods—small wires that look
like microscopic pencils—might improve
medical imaging technology and the way medications
reach targeted parts of the body.
 |
| The
test tube is part of a nanoscience class
experiment where undergraduates synthesize
iron oxide nanocrystals. |
But even an enthusiast like Grassian hesitates
to call this work new. For many researchers,
a UI symposium last year was their first real
opportunity to get a handle on the nanoscientist
label they find themselves wearing.
“We scientists have been working on
the nanoscale for a long time, ever since we’ve
known about molecules and atoms,” Grassian
says. “The difference now is we are paying
attention in new ways. What’s also happening
is that other disciplines are moving more toward
things we chemists and physicists have been
thinking about with molecules and atoms. It’s
a lot of fun, and I believe it has already
changed the way we think about science.”
Nano
Literacy
The new way of thinking about science is seeping
into the curriculum—and not just for
science majors.
“Everybody should be educated about
this,” says chemistry professor Larsen,
who has developed lab lessons in nanoscience
to suit every student from advanced chemistry
and pre-med majors to English and art majors. “We
want scientifically literate students of all
kinds.”
Engineering students also can find nanoscience
lessons in their classrooms and the labs, and
physics and astronomy students can study and
work with researchers who use nanotechnology—the
tools of nanoscience, such as atomic force
microscopes, scanning tunneling microscopes,
and scanning electron microscopes, and other
devices—to not only observe but also
manipulate individual atoms.
“We can use these instruments to pick
up an atom and move it from one place to another,” says
Thomas Boggess, professor and chair of physics
and astronomy in the College of Liberal Arts
and Sciences.
Brooks Landon thinks that sounds like science
fiction. It’s almost impossible to imagine,
says the professor and chair of English in
the College of Liberal Arts and Sciences.
“It’s hard enough picturing one-billionth
of anything, let alone thinking about moving
something that small,” says Landon, who
has spent most of his career in the scholarly
study of science fiction literature and movies. “You
can’t really see what you’re talking
about in nanoscience, even with the best instruments.
If you read the scientific reports, they read
like science fiction, because so much of it
is speculative and everyone is having to imagine
what is going on at the nanoscale level.”
Enormous
Responsibility
Landon says science fiction writers may help
scientists imagine possibilities—both
the potentials and the risks. Even as writers
ponder the dark side of the small science in
popular paperbacks like Michael Crichton’s
, scientists around the country are raising
very real red flags about nanosized molecules
that could damage the lungs and even the brains
of animals.
Grassian wants to make sure nanoscientists
have an opportunity test whether nanoparticles
will harm people or the environment before
the small world of nanoscience arrives in full
force. For her part, she’s using federal
funding to run toxicology studies with experts
in the College of Public Health on new materials
manufactured from nanoscale building blocks.
That kind of preventive work is perhaps the
most important instance of nanoscience compelling
scientists to think in a new way, she believes.
“We’ve been too used to focusing
on the applications with little thought to
the implications,” she says. “Look
at how we handled chlorofluorocarbons in the
1950s. We thought they were the most fantastic
thing in the world—good refrigerants,
good for our cars—until we found out
years later that they were creating a hole
in the ozone layer. Now we’re trying
to understand the risks before we let nanoparticles
get into our streams and our air and our crops.”
English professor Landon acknowledges that
those who control and manipulate this very
small world have enormous responsibility—maybe
even the power to make the dreams of science
fiction come true.
“Science fiction writers often imagine
a better world,” he says. “There’s
talk of using nanoscience to cure disease.
At the same time, Revlon holds more nanotech
patents than any other corporation. So are
we going to change the world? Or just invent
lipstick that sticks on lips better? I think
most scientists recognize the transformative
potential. We’ll have to see what they
do with it.”
by Gary Kuhlmann
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