Fluids on a Conveyor
Today, many analytical processes in medicine, pharmaceutics, and chemistry can be carried out with the help of microfluidic chips that are also referred to as lab-on-a-chip. So far, an individual chip has been designed for every application. Fluids are pumped through very small channels. Small production numbers and complex microfabrication processes, however, lead to high production costs.
State of the art
An alternative may be the transportation of fluids by electric fields, i.e. electric osmosis. This requires high voltages, as a result of which the fluids might be heated up strongly or decompose by electrolysis.
Scientists of the Institute for Nuclear and Energy Technologies (IKET) have developed a microfluidic chip, on which the fluids are transported as if they were located on a conveyor. The chip made of a semiconductor material is divided into small squares similar to a chess board. Every square has the opposite surface charge compared to the neighboring squares. Moreover, electrodes are inserted into the semiconductor material and may generate an electric field in every square. If a fluid, for example water, is applied to the chip, its charged particles are attracted by the chip surface of opposite charge. The charge carriers in the resulting electric double layer are moved by the electric field and entrain a fluid flow due to the viscosity of the fluid. In this way, the fluid can be moved along a track of squares by an alternating direction of the electric field. The required voltages are very low, as only the short distance within a square has to be covered. Every square of up to 100 µm in size acts like the roll of a conveyor belt.
The chip is as flexible as a computer chip and may be programmed for complex analysis or synthesis tasks. In particular, fluids can be decomposed into their constituents by means of electrophoresis and studied for their conductivity.
Options for companies
The KIT looks for partners for the further development and series production of the chip.
Your contact person for this offer
Karlsruhe Institute of Technology (KIT)
Head of Technology Transfer, Innovation and Relations Management (IRM)
Phone: +49 721 608-25582