Microfluidic
integrated circuits have been originated by the researchers of University of
Michigan as a technique to make simple lab-on-a-chip devices that could offer faster,
low-cost and more portable medical tests.
These
microfluidic circuits control the flowing of fluid through their devices
without directions from outside systems. This process is similar to the
computer chips where electronic circuits intelligently route the flow of
electricity without external controls
A
paper on the technology is recently disclosed online in Nature Physics.
A
microfluidic device, or lab-on-a-chip, combines more than one laboratory operations
onto one chip only centimeters in size. The devices make allowance for the
researchers to experiment with very small sample sizes, and also to perform
multiple experiments on the same material at the same time. They can be cut out
to simulate the human body more nearly than the Petri dish does. They could
lead to on-the-spot home tests for illnesses, food contaminants and toxic gases
are major among other advances.
"In
most microfluidic devices today, there are essentially little fingers or
pressure forces that open and close each individual valve to route fluid
through the device during experiments. That is, there is an extra layer of
control machinery that is required to manipulate the current in the fluidic
circuit," said Shu Takayama, the principal investigator on the project.
Takayama is an associate professor in the U-M Department of Biomedical
Engineering.
That's
same to how electronic circuits were manipulated a century before. Then, with
the improvement of the integrated circuit, the "thinking" became
embedded in the chip itself -- a technical step forward that enabled personal
computers, Takayama said.
"We
have literally made a microfluidic integrated circuit," said Bobak
Mosadegh, a doctoral student in Takayama's lab who is first writer of the
paper.
The
outer controls that power today's microfluidic devices may be inconvenient. Every
valve on a chip (and there could be dozens of them) needs its individual
electromechanical push from an off-chip actuator or pump. This has made it hard
to shrink microfluidic systems to palm- or fingertip-sized diagnostic devices.
The
Takayama lab's innovation is a step in this direction. His research group has
devised a strategy to produce the fluidic counterparts of key electrical
components including transistors, diodes, resistors and capacitors, and to
efficiently network these components to automatically regulate fluid flow
within the device.
Because
of the use of conventional techniques in the making of these components, they
are suitable for all other microfluidic components such as mixers, filters and
cell culture chambers.
"We've
made a versatile control system," Mosadegh said. "We envision that
this technology will become a platform for researchers and companies in the
microfluidics field to develop sophisticated self-controlled microfluidic
devices that automatically process biofluids such as blood and pharmaceuticals
for diagnostics or other applications.
"Just
as the integrated circuit brought the digital information processing power of
computers to the people, we envision our microfluidic analog will be able to do
the same for cellular and biochemical information."
The
university is pursuing patent protection for the intellectual property, and is
seeking commercialization partners to help bring the technology to market.
