Micromachines 2016, 7(11), 214; doi:10.3390/mi7110214
Microfluidic Mixing and Analog On-Chip Concentration Control Using Fluidic Dielectrophoresis
Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Maryland Hall 220A, Baltimore, MD 21218, USA
*
Author to whom correspondence should be addressed.
Academic Editors: Xiangchun Xuan and Shizhi Qian
Received: 4 October 2016 / Revised: 11 November 2016 / Accepted: 14 November 2016 / Published: 23 November 2016
(This article belongs to the Special Issue Micro/Nano-Chip Electrokinetics)
Abstract
Microfluidic platforms capable of complex on-chip processing and liquid handling enable a wide variety of sensing, cellular, and material-related applications across a spectrum of disciplines in engineering and biology. However, there is a general lack of available active microscale mixing methods capable of dynamically controlling on-chip solute concentrations in real-time. Hence, multiple microfluidic fluid handling steps are often needed for applications that require buffers at varying on-chip concentrations. Here, we present a novel electrokinetic method for actively mixing laminar fluids and controlling on-chip concentrations in microfluidic channels using fluidic dielectrophoresis. Using a microfluidic channel junction, we co-flow three electrolyte streams side-by-side so that two outer conductive streams enclose a low conductive central stream. The tri-laminar flow is driven through an array of electrodes where the outer streams are electrokinetically deflected and forced to mix with the central flow field. This newly mixed central flow is then sent continuously downstream to serve as a concentration boundary condition for a microfluidic gradient chamber. We demonstrate that by actively mixing the upstream fluids, a variable concentration gradient can be formed dynamically downstream with single a fixed inlet concentration. This novel mixing approach offers a useful method for producing variable on-chip concentrations from a single inlet source. View Full-Text
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).
Share & Cite This Article
MDPI and ACS Style
Mavrogiannis, N.; Desmond, M.; Ling, K.; Fu, X.; Gagnon, Z. Microfluidic Mixing and Analog On-Chip Concentration Control Using Fluidic Dielectrophoresis. Micromachines 2016, 7, 214.
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.
Related Articles
Article Metrics
Comments
[Return to top]
Micromachines
EISSN 2072-666X
Published by MDPI AG, Basel, Switzerland
RSS
E-Mail Table of Contents Alert