Funding boost to develop microchips for pathogen detection

A microfabrication technique to develop three-dimensional microfluidic devices in polymers could help identify unwanted particles in food and water.

The research has received a National Science Foundation (NSF) award of $353,091 to use the technology and develop new microchips named 3D-πDEP standing for "three-dimensional, passivated-electrode, insulator-based dielectrophoresis" for pathogen detection.

Microfluidics deals with the performance, control, and treatment of fluids that are constrained in some fashion, according to the research from Virginia Tech's Microelectromechanical Systems Laboratory (MEMS) Laboratory in the Bradley Department of Electrical and Computer Engineering.

Use of microfluidic devices

Microfluidic devices can be used to trap and sort living organisms such as bacteria, viruses, and cells.

Masoud Agah, director of the laboratory and associate professor of the Bradley Department of Electrical and Computer Engineering and Amy Pruden, professor of civil and environmental engineering at Virginia Tech, spearheaded the study.

The NSF grant will allow them to focus on the isolation of waterborne pathogens, said Agah who also works at the Virginia Tech–Wake Forest School of Biomedical Engineering and Sciences.

Agah said researchers have mainly used two-dimensional microfluidic structures since this type of fabrication is more simplistic.

However, with the three-dimensional device he developed with graduate students Yayha Hosseini and Phillip Zellner, they are able to customize the shapes of the channels and cavities of the devices the fluids passed through.

Channels and cavities

The advantage of the fabrication process is that with an economical technique it creates three-dimensional varying channels and cavities in a microfluidic structure with rounded corners and other customized shapes.

These shapes resemble the living conditions as they occur naturally and this allows the use of the three-dimensional microfabrication technology beyond pathogen detection.

“Only under this type of condition can one truly study the biology of cells within a system in vitro as if it is occurring in vivo – our new microfluidic fabrication technology can resemble more realistically the structures of a cell's true living conditions," said Agah.

He added that with the three-dimensional device that has a higher sensitivity and throughput than the two-dimensional version, is able to make their predictions of applications ranging from water and food safety to fighting biological and chemical terrorism.

To make the three-dimensional structure, the Virginia Tech researchers used the material polydimethylsixolane, known for its elastic properties similar to rubber.

This material is already widely used because of its transparency, biocompatibility, and low-cost, they said.