From pacemakers constructed of materials that so
closely mimic human tissues that a patient's
body can't discern the difference to devices that bypass
injured spinal cords to restore movement to
paralyzed limbs, the possibilities presented by organic
electronics read like something from a science
Derived from carbon-based compounds (hence the term
"organic"), these "soft" electronic
materials are valued as lightweight, flexible, easily
processed alternatives to "hard" electronics
components such as metal wires or silicon semiconductors.
And just as the semiconductor industry is
actively developing smaller and smaller transistors, so,
too, are those involved with organic electronics
devising ways to shrink the features of their materials so
that they can be better utilized in
bioelectronic applications such as those above.
To this end, a team of chemists at Johns Hopkins has
created water-soluble electronic
materials that spontaneously assemble themselves into
"wires" much narrower than a human hair. An
article about their work was published in a recent issue of
the Journal of the American Chemical
"What's exciting about our materials is that they are
of size and scale that cells can intimately
associate with, meaning that they may have built-in
potential for biomedical applications," said John D.
Tovar, an assistant professor in the Department of
Chemistry in the Krieger School of Arts and
Sciences. "Can we use these materials to guide electrical
current at the nanoscale? Can we use them to
regulate cell-to-cell communication as a prelude to
re-engineering neural networks or damaged spinal
cords? These are the kinds of questions we are looking
forward to being able to address and answer in
the coming years."
The team used the self-assembly principles that
underlie the formation of beta-amyloid
plaques, which are the protein deposits often associated
with Alzheimer's disease, as a model for their
new material. This raises another possibility: that these
new electronic materials may eventually prove
useful for imaging the formation of these plaques.
"Of course, much research has been done and is still
being done to understand how amyloids
form and to prevent or reverse their formation," Tovar
said. "But the process also represents a
powerful new pathway to fabricate nanoscale materials."
This research was supported by The Johns Hopkins