Passive microfluidic control of two merging streams by capillarity and relative flow resistance.
In the progress of microfluidic devices, a simple and precise control of multiple streams has been essential for complex microfluidic networks. Consequently, microfluidic devices, which have a simple structure, typically use external energy sources to control the multiple streams. Here, we propose a pure passive scheme that uses capillarity without using external force or external regulation to control the merging of two streams and even to regulate their volumetric flow rate (VFR). We accomplish this process by controlling the geometry of two inlets and a junction, and by regulating the hydrophilicity of a substrate. Additionally, we use the relative flow resistance to control the VFR ratio of the merged two streams. Our results will significantly simplify the control of multiple streams without sacrificing precision.
Kim
Sung-Jin
SJ
Biosensor Group, Electronics and Telecommunications Research Institute, Daejeon 305-350, Korea. yahokim@etri.re.kr
Lim
Yong Taik
YT
Yang
Haesik
H
Shin
Yong Beom
YB
Kim
Kyuwon
K
Lee
Dae-Sik
DS
Park
Se Ho
SH
Kim
Youn Tae
YT
D002197:Capillary Action; D044085:Microfluidics / Q000295:instrumentation* / Q000379:methods*; D014867:Water / Q000737:chemistry
D014867:Water