A microfluidic chip that can predict signs of stroke from a mere 1% of a blood droplet and medical devices that can cure a cell the size of a red blood cell sound like the technology in SF movies. But a Korea-US joint research team’s electrokinetic (EK) pump is making this possible in reality.

Sanghyun Lee, a Ph.D in the Department of Mechanical Engineering, and Alan Hunt of the University of Michigan and his research team discovered that insulators, at the nanoscale, can have electrical conductivity, and fabricated the EK pump, which is the smallest man-made one created yet. Selected as the featured paper, the result was published on the renowned journal, Nature Nanotechnology, on May 17 online.

The joint research team found out that there can be reversible transition of dielectric materials, such as glass, to conductors at the nanoscale under mild potentials. Based on these findings, they introduced nanoscale liquid glass electrodes (NLGE), which can function as three-dimensional nano-electrodes in nanodevices. The past difficulty in fabricating fluidic actuators or sensors with multiple materials to make an electrode has been eliminated as there is no need to integrate conducting and non-conducting materials in a single device. The fabrication of the NLGE-based EK pump demonstrated that these electrodes can be integrated into a nanodevice.

This novel form of electrode is expected to be easily implemented into lab-on-a-chip devices and other nanofluidic systems.