Field-effect pump: liquid dielectrophoresis along a virtual microchannel with source-gate-drain electric fields
Journal
Lab on a Chip
Journal Volume
21
Journal Issue
12
Pages
2372-2382
Date Issued
2021
Author(s)
Abstract
We investigate liquid dielectrophoresis (LDEP) to implement field-effect pumps (FEPs) that drive liquids from source,viagate, toward drain electric fields between parallel plates without external pumps or the problem of dead volume. The appropriate gate electric field establishes a wall-less virtual microchannel to transfer the liquid from source to drain with an adjustable flow rate (Q) controlled by the difference of the square of the electric field strength (ΔE2DS). Analogous to field-effect transistors (FETs), the FEPs can operate in a “linear”, “transition” or “saturation” region depending on ΔE2GDand ΔE2DS. With a sufficient ΔE2GDand a small ΔE2DS, the FEPs operated in the linear region whereQwas linearly proportional to ΔE2DSand inversely proportional to the flow resistanceRthat was mainly determined by the length (L), width (W) and height (H) of a stable and fully-occupied virtual microchannel. With an insufficient ΔE2GDand a moderate to large ΔE2DS, narrowing, tapering and even pinch-off of virtual microchannels were observed, which increasedRand changed the operation into the transition or saturation region. A field-effect stream merger regulating two streams was built based on two FEPs with shared gate and drain electrodes. The versatility of FEPs was demonstrated with preliminary studies on whole blood and particle solutions. ? The Royal Society of Chemistry 2021.
Subjects
Electric field effects; Electrophoresis; Liquids; Microchannels; Pumps; Drain electrodes; Electric field strength; Field effect transistor (FETs); Linearly proportional; Liquid dielectrophoresis; Parallel plates; Particle solutions; Saturation region; Field effect transistors
Type
journal article