We demonstrate an electrohydrodynamic (EHD) technique for separating giant unilamellar vesicles by size in polydisperse suspensions. An oscillatory electric field (∼30 Hz) generates EHD flow around each vesicle close to an electrode. Nearby vesicles are entrained in the flow and the vesicles move toward one another. Upon aggregation, smaller vesicles are pulled underneath the larger vesicles, which ultimately lifts them off of the electrode. A brief spike in the electric field then serves to irreversibly adhere the bottom layer of smaller vesicles to the electrode, and the large vesicles are subsequently removed by flow. We demonstrate that a single application of this technique can remove more than 90% of the smallest vesicles (diameter <20 μm) from a suspension of electroformed giant lipid vesicles.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)