%0 Journal Article %J Journal of Microelectromechanical Systems %D 2010 %T Flow control using a thermally actuated microfluidic relay valve %A Bazargan, V %A Stoeber, B %I ASME/IEEE %N 5 %P 1079-1087 %U http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=5575368 %V 19 %X This work demonstrates a new 2-stage valving concept for microfluidic systems that uses the reversible gelation of a thermally responsive polymer solution in a control channel to deflect a membrane into the main flow channel for flow control. This method can control flow through a system of microchannels using integrated electric heating elements and only one control pressure source, compared to the off-chip pressure manifold needed in existing systems. This valve technology therefore enables portable microfluidics-based diagnostics tools for biomedical applications and environmental monitoring allowing on-site analysis. Valves with zero leakage rates and a response time of about 3 seconds have been achieved. %8 10/2010