High-throughput positive-dielectrophoretic bioparticle microconcentrator.

We introduce a new dielectrophoretic particle microconcentrator that combines interdigitated electrodes with a chaotic mixer to achieve high-throughput (>100 microL/min) particle concentration. The interdigitated electrodes use positive dielectrophoresis to attract particles to the surface, while the chaotic mixer circulates the particles to increase the number brought in proximity with the surface. We have used this microconcentrator to concentrate both beads and B. subtilis spores and have developed a microvolume concentration measurement method to determine the delivered off-chip concentration enhancement of the output sample. The resulting microconcentrator is sufficiently high throughput to serve as an interface between macroscale sample collectors and micro- or nanoscale detectors.