Microfluidic valve array control system integrating a fluid demultiplexer circuit

This paper proposes an efficient control method for the large-scale integration of microvalves in microfluidic systems. The proposed method can control 2(n) individual microvalves with 2n + 2 control lines (where n is an integer). The on-chip valves are closed by applying pressure to a control line, similar to conventional pneumatic microvalves. Another control line closes gate valves between the control line to the on-chip valves and the on-chip valves themselves, to preserve the state of the on-chip valves. The remaining control lines select an activated gate valve. While the addressed gate valve is selected by the other control lines, the corresponding on-chip valve is actuated by applying input pressure to the control line to the on-chip valves. Using this method would substantially reduce the number of world-to-chip connectors and off-chip valve controllers. Experiments conducted using a fabricated 2(8) microvalve array device, comprising 256 individual on-chip valves controlled with 18 (2 x 8 + 2) control lines, yielded switching speeds for the selected on-chip valve under 90 ms.