portable device similar to today's home pregnancy
tests that can quickly detect the presence of infectious
diseases, including HIV-AIDS and measles, as well
as biological agents such as ricin and anthrax, is
the object of a new joint university/industry research
University's Institute for Integrative Biosystems
Research and Education (VIIBRE) and Pria Diagnostics
LLC, a privately held California company that specializes
in miniaturized medical diagnostics, agreed to collaborate
on the development before the holidays.
has spent the last three years developing the ability
to measure the metabolism of small groups of cells
and studying how they respond to drugs, toxins and
pollutants. To do so, the interdisciplinary team has
developed two basic technologies: special electrodes
that can measure the concentrations of the chemicals
that cells consume and excrete in extremely small
volumes and the use of fluids flowing through microscopic
channels to move and manipulate small numbers of cells
reliably. In the process, the group has applied for
more than 12 patents.
Pria has developed a micro-optical fluorescence spectroscopy
system and used it as the basis for a inexpensive
male fertility detector that can be used in the home
to measure sperm motility with an accuracy comparable
to laboratory analyses.
thrilled at how well the VIIBRE and PRIA technologies
mesh," says John P. Wikswo, professor of biomedical
engineering, physiology and physics at Vanderbilt
and director of VIIBRE. "We are already making
rapid progress on prototyping portable instruments
for clinical diagnosis and biodefense."
the treatment for AIDS is very expensive and there
is always a question about when to start and stop
anti-retroviral therapy," says Pria's Chief Technology
Officer Jason Pyle. "We are developing a device
that we hope will allow medical professionals and
HIV patients to manage their disease in a way that
is similar to how diabetes patients can monitor their
condition since the introduction of home blood glucose
detectors." The collaboration's goal is to produce
its first portable HIV monitor within two years. In
addition to such "point of care" devices,
Wikswo and Pyle are joining forces to develop "high-throughput"
screening systems that can determine the biological
activity of large numbers of compounds with extreme
rapidity and so could have a major impact on the drug
years ago a number of start-up companies were created
to make the goal of creating a "lab-on-a-chip"
a reality. However, putting microscopic arrays of
channels, pumps and valves to move around minute amounts
of liquid on silicon chips proved to be considerably
more difficult than most of the inventors had expected
and the products that these companies have created
thus far have been too expensive for the point-of-care
their home fertility tester, Pria kept costs down
by keeping their system as simple as possible. Instead
of trying to squeeze everything onto a single chip,
Pria designers started with a desktop diagnostic system
and shrank it down into a device about the size of
a coffee cup. One of the cost-saving aspects of the
design was to keep the fluid-handling components separate
from the microelectronics. The resulting device is
considerably larger than comparable lab-on-a-chip
systems but it is also much less expensive. "That's
one of the appealing features about Pria's approach,"
says Wikswo, "They keep their microfluidics and
microelectronics as simple as possible."
first product focused on fertility," says VIIBRE
project engineer David Schaffer. "With our capabilities,
they can begin applying their technology to a goldmine
of different applications."
of the key VIIBRE capabilities, which was developed
by a research team headed by Assistant Professor of
Chemistry David Cliffel, is the development of a sensor
suite capable of simultaneously measuring the concentrations
of the key chemicals that cells consume and excrete--oxygen,
glucose and lactic acid--with enough sensitivity to
monitor the health of a few thousand cells confined
in a small volume. (For more detail see "New
device can help defend against novel biological agents"
the leadership of Franz Baudenbacher, assistant professor
of biomedical engineering and physics, Vanderbilt
researchers have further miniaturized this sensor
technology to record rapid changes in the metabolism
and signaling of individual cells. To handle such
small numbers of cells, they have adapted a method
for molding micro-channels and valves into a material
similar to that used in soft contact lenses. This
has given them the capability to capture, manipulate,
grow and study single living cells in extraordinarily
small containers--volumes that are barely larger than
the cells themselves.
sensors that have been developed to identify toxic
agents are single purpose. That is, they can identify
the presence of a single toxin, or a limited number
of closely related toxins. The ability to monitor
the health of small groups of cells, however, makes
it possible to detect the presence of unknown poisons
as long as they affect cell metabolism. Furthermore,
by examining the impact that an unknown agent has
on different cell types--such as heart, lung, nerve,
skin, etc.--this approach also can rapidly provide
critical insights into its mode of action.
has an outstanding understanding of the clinical and
diagnostic device market and the ability to rapidly
prototype optical and microfluidics devices,"
says Wikswo, "but it is difficult for the company
to survey large numbers of possible applications.
Yet, here at the university, searching for new applications
is one of the things that we do best."
origin of the collaboration is an example of the power
of serendipity. It started when David Schaffer, a
VIIBRE student who stayed on at the institute as a
project engineer after he graduated, was browsing
the Web looking for a permanent job. Although looking
for a local position, he inadvertently opened a Web
page with listings from California. He came across
an interesting opening at Pria, located in Menlo Park,
and decided to apply. Although Pria decided that he
wasn't the right person for the job, in their correspondence
Pyle expressed potential interest in collaborating
with VIIBRE. Schaffer passed the information along
to Wikswo, who gave Pyle a call. That was in early
September. By mid-November a joint research agreement
for $120,000 for the first year was completed and
For more news about Vanderbilt research, visit Exploration,
Vanderbilt's online research magazine, at www.exploration.vanderbilt.edu.