24, No. 17, March 17, 20054
plans to build things with bricklike corn molecules
ACES Media/Communications Specialist
photo to enlarge
<strong>Photo by L. Brian Stauffer</strong><hr /><br />
nanotechnologist Graciela Wild Padua examines a
slide that will hold a corn zein scaffold. Padua,
a researcher in the department of food science and
human nutrition, hopes that eventually scientists
will be able to make “boxes, tubes or cages”
from zein, and these structures will carry other
molecules inside them.
Graciela Wild Padua is intrigued by the bricklike shape of the corn
zein molecule. She thinks it’s particularly suited as a building
block for tiny structures small enough to be measured in nanometers:
cages, for example, that could carry biocompounds to targeted sites
in the human body or scaffolds on which to grow neat sheets of skin
cells instead of bulky clumps of tissue.
Nanotechnology is most often mentioned in connection with microelectronics,
with tiny computer chips and wires that can be measured in nanometers.
A nanometer is one-thousandth of a micron, and a micron is one-thousandth
of a millimeter.
And zein is just a waste product in the corn-to-ethanol process. But
this corn byproduct won’t be wasted much longer if Padua, a researcher
in the department of food science and human nutrition in the College
of Agricultural, Consumer and Environmental Sciences, has her way.
“The corn zein molecule has a very special bricklike shape, and
we think we can build with it in much the same way that children play
with Lego bricks and make towers,” she said. Padua hopes that
eventually scientists will be able to make “boxes, tubes or cages”
from zein, and these structures will carry other molecules inside them.
“A physician may want a particular drug to attach itself to a
particular part of the body or act upon only a certain kind of tissue,”
she said. “A cancer treatment would be an example.”
“These chemical molecules will have to remain intact until they
reach their intended site,” she said, “so they’ll
need to be wrapped and carried in something else. Otherwise, they could
be degraded in the stomach or expand in other channels.” That
“something else” could be a corn zein carrier.
Padua said there is also interest among scientists in finding materials
suitable for frames to support the growth of cells in sheets for medical
purposes. Again, a scaffold built of corn zein molecules could fill
And, when scientists need to channel cell growth, they require a structure
that guides the cells in certain directions. “Some scientists
are interested in growing single neurons, for instance, but you’d
have to channel the dendrites to go to certain places. They couldn’t
just grow wildly because they have to be connected to certain points.
Zein molecules could provide that sort of structure,” she said.
The researcher said they’re not quite there yet. “Right
now, we’re manipulating the environment in the lab, and we’re
attempting to build lines and walls from molecules of corn zein.”
The scientists are changing the solvent and adding or removing certain
ions or materials that could alter zein’s reactivity, making it
stickier and thus better “building” material.
“Right now, we’re concentrating on getting zein to perform
predictably as a building material so we can recommend that it be used
in these other ways,” she said.
Padua said it’s not easy building scaffolding or other structures
at the molecular level because “molecules tend to go their own
way. But preliminary research with corn zein has been promising. Because
zein molecules are so bricklike, we should be able to line them up precisely
one right after another and make things with them.”
It’s exacting work, done one molecule at a time. But Padua sees
potential in these bricklike molecules. She believes they have a part
to play in 21st century medicine.
Other researchers working on the project are Antony Crofts, professor
of biochemistry and in the Beckman Institute; Phillip Geil, professor
of materials science and engineering; Jin-Feng Wang, graduate research
assistant; and Qin Wang, postdoctoral researcher. Preliminary research
has been published in the Journal of Agricultural Food Chemistry and
Biomacromolecules. Funding was provided by the Illinois Agricultural
Experiment Station and the Illinois Corn Marketing Board.