Microfluidic transport based on direct electrowetting

Abstract

Access to the full text of the published version may require a subscription. An integrated microfluidic system was fabricated which functions by deliberately manipulating interfacial tension. A distinctive characteristic of our system is the use of an array of adjacent, elongated, working electrodes and protruding polydimethylsiloxane open-flow channels. Microfluidic transport was realized directly on the bare gold electrode surface in the absence of an additional dielectric layer. By changing the potential of the working electrode to a negative potential, a liquid column could be transported from one end of an elongated working electrode to the other end. Transport of the liquid column could be altered without any valves by switching on the adjacent electrode in a given direction. The flow velocity depended on the applied potential, i.e., the velocity could be altered by deliberate manipulation of the electrode potential. In addition, the flow velocity increased as the dimensions of the flow channel decreased. The applied voltage was less than 2 V, and the power consumption was in the order of tens of W. Rights

A Mixed Finite Element Method for EWOD That Directly Computes the Position of the Moving Interface

“…Thus, the droplet can move, split, and merge in a controlled fashion. Several applications use EWOD as a main driving force: mass spectrometry [44,25], 'lab-on-a-chip' [33,18,20,32], particle separation/concentration control [10,41], auto-focus cell phone lenses [5], and colored oil pixels for laptops and video-speed smart paper [19,30,31].…”

Numerical Simulation for a Droplet Fission Process of Electrowetting on Dielectric Device

“…To avoid electrolysis, an insulating layer is usually inserted between the droplet and electrodes [4]- [6]. The applications of EWOD devices were discussed extensively in the literature, including microfluid transport [7], tunable optical fiber devices [8], rotating liquid micromotor [9], micro-injection [10], particle separation and concentration control [11]. Other studies focusing on the modeling of EWOD devices can be found in [3,5,[12][13][14][15].…”

The Nonlinear Phenomena of Thin Polydimethylsiloxane (PDMS) Films in Electrowetting

“…In the current research about EWOD, the phenomena on different dielectric materials are studied [7][8][9][10], and the applications in micro-devices are developed fast [11][12][13][14][15]. The interpretation about the principle of EW also attracts much attention [16][17][18].…”