Document Type
Article
Publication Date
2-1-2015
Abstract
Microfluidic CD platforms are utilized to perform different biological processes and chemical analyses. In general, a microfluidic CD implements the centrifugal force that is created by the spinning of the platform to pump liquid through the microfluidic network of chambers and channels. Over the last few decades, a wide range of active and passive valving methods were proposed and tested on various microfluidic platforms. Most of the presented valves are too complex to design and involve lengthy fabrication processes. In this paper, easy to fabricate air and liquid check valves for centrifugal microfluidic platforms are presented: a Terminal Check Valve (TCV) and a Bridge Check Valve (BCV). To understand the characteristic of the proposed valves, theoretical and experimental studies are conducted. Moreover, to test the effectiveness of these valves, liquid swapping is demonstrated by integrating TCV and BCV chips with thermo-pneumatic (TA) pumping on a CD. The valves are shown to accurately control flow direction which makes them an excellent choice for a variety of complex microfluidic processes. The experimental and theoretical results also indicate that these valves require low pressure for actuation. Furthermore, the theoretical results confirm the ability to adjust the required actuation pressure by changing the valve chip size. Finally, as a proof of concept for implementing the check valves on a biological application, an enzyme linked immunosorbent assays (ELISA) is performed. The result shows that the TOT and BCV valving chips enhance the operating range of the processes that can be performed on the microfluidic CD. (C) 2014 Elsevier B.V. All rights reserved.
Keywords
Centrifugal platform, microfluidic cd, passive check valve, thermo-pneumatic pumping, terminal check valve, bridge check valve, analysis systems, microvalve, micropump, design
Divisions
fac_eng
Funders
UM High Impact Research UM-MOHE UM.C/625/1/HIR/MOHE/05,Fundamental Research Grant Scheme (FRGS) from the Ministry of Higher Education Malaysia FP042-2013B ,University of Malaya Research Grants UMRG: RG023/09AET UMRG RP009A-13AET University Malaya ,Yayasan Sultan Iskandar Johore Foundation
Publication Title
Sensors and Actuators A: Physical
Volume
222
Publisher
Elsevier
Additional Information
Cb4bo Times Cited:0 Cited References Count:34