Dielectrophoretic cage-speed separation of bio-particles

A novel approach to the size characterization and separation of bio-particles is presented. Fluid-flow is not required to activate the separation since moving dielectrophoretic cages (MDC) (G. Medoro et al., IEDM, pp. 415-418, 2000) are used. By sequencing a set of cage patterns in a micro-fabricated chip, a movement can be induced or not on bio-particles depending on the ratio between the dielectrophoretic (DEP) mobility (H. Morgan and N.G. Green, Research Studies Press, 2003) and the cage-speed, causing selective particle transport. The effectiveness of the approach has been proven by experimental results with different sized beads. This approach can be easily combined with optical or impedance measurement for on-chip quantification of the mixture constituents for a miniaturized, automatic detection system.