A New Polymer Product from Soy Oil, Not
Petroleum By Jan
Suszkiw May 2, 2008
Hair-care products, wound-care dressings and drug encapsulation
are among the potential uses of new, soy-oil-based polymers known as
"hydrogels," developed by Agricultural Research Service (ARS) scientists in Peoria, Ill.
Liu developed the soy-oil-based hydrogels as a biodegradable alternative to
the synthetic polymers now used, including polyacrylic acid and polyacrylamide.
Soy oil is an appealing raw material to use because it is chemically
versatile, abundant and renewable--meaning the crop can be replanted each year
to renew the supply. In 2006, U.S. farmers planted 76 million acres of
soybeans, equal to about 38 percent of the world's total oilseed production,
notes Erhan. She and Liu both work at ARS'
Center for Agricultural Utilization Research in Peoria.
They first began investigating soy-oil-based hydrogels in 1999 as part
of the Peoria center's mission of exploring new, value-added uses for corn,
soybeans and other Midwest crops. Using a two-step process--ring-opening
polymerization and hydrolysis--they created a squishy but durable hydrogel
polymer that expands and contracts in response to changes in temperature and
In tests, they observed that the hydrogel's water-absorbing capacity
was lower than that of petroleum-based polymers. But this later proved to be a
plus. In collaboration with Erhan and Liu, a University of Toronto scientist successfully
formulated the hydrogel into nanoparticles that encapsulate the breast cancer
drug doxorubicin. In drug-release experiments, nanoparticle-delivered
doxorubicin proved eight times more toxic to cancerous cell lines than when
lipid-water solutions were used.
Soy proteins are known allergens, but Erhan doesn't anticipate this
posing a problem to the nanoparticles' use as drug-delivery agents. That's
because soy oil's chemical structure is completely changed by the two-step
manufacturing process used to make the hydrogel.
more about the research in the May/June 2008 issue of Agricultural Research
ARS is the U.S. Department of
Agriculture's chief scientific research agency.