Affiliation: | 1. Faculty of Mechanical Engineering, Technion—, Israel Institute of Technology, Technion City, 3200003 Haifa, Israel IBM Research Europe, Säumerstrasse 4, 8803 Rüschlikon, Switzerland These authors contributed equally to this work.;2. Faculty of Mechanical Engineering, Technion—, Israel Institute of Technology, Technion City, 3200003 Haifa, Israel Current address: Department of Electrical and Computer Engineering, University of California San Diego, San Diego, CA, 92093 USA;3. IBM Research Europe, Säumerstrasse 4, 8803 Rüschlikon, Switzerland;4. Faculty of Mechanical Engineering, Technion—, Israel Institute of Technology, Technion City, 3200003 Haifa, Israel |
Abstract: | We present a new concept for on-chip separation that leverages bidirectional flow, to tune the dispersion regime of molecules and particles. The system can be configured so that low diffusivity species experience a ballistic transport regime and are advected through the chamber, whereas high diffusivity species experience a diffusion dominated regime with zero average velocity and are retained in the chamber. We detail the means of achieving bidirectional electroosmotic flow using an array of alternating current (AC) field-effect electrodes, experimentally demonstrate the separation of particles and antibodies from dyes, and present a theoretical analysis of the system, providing engineering guidelines for its design and operation. |