“For the detection of biomolecules, we usually first have to isolate them in a complex medium in a device and then send them to another device or another spot in the same device for detection,” says Ping, who is also affiliated with the Institute of Applied Life Sciences. “Now we can isolate them and detect them at the same microscale spot in a microfluidic device at the same time.
“No one has ever demonstrated this before,” he continues. “This is owing to our use of graphene, a nanomaterial as thing as a single carbon atom, as microelectrodes in a microfluidic device. We found that, compared to typical inert-metal microelectrodes, the electrolysis stability for graphene microelectrodes is more than 1,000 times improved, making them ideal for high-performance electrokinetic analysis.”
Also, Ping added, since monolayer graphene is transparent, “we developed a three-dimensional multi-stream microfluidic strategy to microscopically detect the isolated molecules and calibrate the detection at the same time from a direction normal to the graphene microelectrodes.”
The new approach developed in the work paves the way to the creation of lab-on-a-chip devices of maximal time and size efficiencies, Ping says. Also, the approach is not limited to analyzing biomolecules and can potentially be used to separate, detect and stimulate microorganisms such as cells and bacteria.
Co-authors on the paper, “Graphene-Enabled High-Performance Electrokinetic Focusing and Sensing,” are Ping’s students, Xiao Fan (first author) and Xiaoyu Zhang. The research is supported by Ping’s 2020 Young Investigator Program (YIP) award from the Air Force Office of Scientific Research (AFOSR). The goal of Ping’s YIP project is to develop a new technology for long-term, high-spatiotemporal resolution, high-sensitivity electrical detection and stimulation of large-scale biosystems.
The Ping Lab at the Life Science Laboratories is interested in novel properties at the interface of nanomaterials and biosystems and the downstream applications in the development of biomedical tools, healthcare, point-of-care diagnostics and environmental monitoring.
Read the original article on University of Massachusetts Amherst.