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CPP: Fachverband Chemische Physik und Polymerphysik

CPP 34: Microfluidics I: Applications and Devices

CPP 34.3: Vortrag

Donnerstag, 26. März 2009, 10:00–10:15, ZEU 160

Manipulation of nanoparticles by turbulent electrohydrodynamic flows — •Michael Boettcher, Magnus Jaeger, and Claus Duschl — Fraunhofer Institute for Biomedical Engineering (IBMT), Am Muehlenberg 13, 14476 Potsdam, Germany

Several methods for the manipulation of micro- and nanoparticles have attracted interest in medicine and biotechnology. Especially, lab-on-chip systems (LOC) found their applications due to their fine fluid channels being of the same length scale as the objects under test. An attribute of these micrometre-sized channels is a continuous fluid flow. In conventional LOCs these flows are often generated by external pressure-driven pumps. A alternative path to establish a fluid transport is a high-frequency, electrical travelling wave. This mechanism can be integrated directly into the chip and works without any moving parts. To this end, an array of parallel electrode elements provides the driving, electrical field. Under special circumstances, the induced fluid flow is accompanied by vortices above the electrodes. The establishment of these turbulent flows in our microfluidic device - which is defined by small Reynolds numbers and, therefore, a laminar flow - indicated a potential of the system for a new application. Our goal is to optimise these vortices to manipulate especially nanometre-sized particles e. g. viruses. For that it is essential to get a better understanding of the vortices. We use the travelling wave mechanism to accumulate artificial, fluorescent beads. The advantage of our system is the defined accumulation of nanometre-sized particles in the absence of any filtering material.