title: Rapid Particle Patterning in Surface Deposited Micro-Droplets of Low Ionic Content via Low-Voltage Electrochemistry and Electrokinetics.
abstract: Electrokinetic phenomena are a powerful tool used in various scientific and technological applications for the manipulation of aqueous solutions and the chemical entities within them. However, the use of DC-induced electrokinetics in miniaturized devices is highly limited. This is mainly due to unavoidable electrochemical reactions at the electrodes, which hinder successful manipulation. Here we present experimental evidence that on-chip DC manipulation of particles between closely positioned electrodes inside micro-droplets can be successfully achieved, and at low voltages. We show that such manipulation, which is considered practically impossible, can be used to rapidly concentrate and pattern particles in 2D shapes in inter-electrode locations. We show that this is made possible in low ion content dispersions, which enable low-voltage electrokinetics and an anomalous bubble-free water electrolysis. This phenomenon can serve as a powerful tool in both microflow devices and digital microfluidics for rapid pre-concentration and particle patterning.
authors: Department of Materials Science and Engineering Faculty of Engineering &University Center for Nano Science and Nanotechnology Tel Aviv University, Tel-Aviv, 69978, Israel.
authors: Noam
authors: N
authors: Sidelman
authors: Faculty of Engineering and the Nanotechnology Center, Bar-Ilan University, Ramat-Gan, 5290002, Israel.
authors: Moshik
authors: M
authors: Cohen
authors: Zernike Institute for Advanced Materials, Department of Polymer Chemistry, University of Groningen, Nijenborgh 4, 9747AG Groningen, Netherlands.
authors: Anke
authors: A
authors: Kolbe
authors: Faculty of Engineering and the Nanotechnology Center, Bar-Ilan University, Ramat-Gan, 5290002, Israel.
authors: Zeev
authors: Z
authors: Zalevsky
authors: Zernike Institute for Advanced Materials, Department of Polymer Chemistry, University of Groningen, Nijenborgh 4, 9747AG Groningen, Netherlands.
authors: Andreas
authors: A
authors: Herrman
authors: Department of Materials Science and Engineering Faculty of Engineering &University Center for Nano Science and Nanotechnology Tel Aviv University, Tel-Aviv, 69978, Israel.
authors: Shachar
authors: S
authors: Richter