Miniature conductive polymer actuators for high pressure generation in lab on chip systems

We developed a miniaturized ‘syringe type’ pump (8 mm diameter, 1 mm thickness) which generates a flow rate of 2 μL/min at a pressure of 3 MPa. It consists of a stack of several conductive polymer (CP) layers intercalated with electrolyte layers. The stack is housed in a polycarbonate case specially conceived for integration in a lab-on-chip device. The dependence of strain on applied bias is investigated and the optimum working condition is determined. The actuator operates at a bias lower than 2 V.A maximum strain of 13% is measured in the single CP layer when it expands against atmospheric pressure; this strain is reduced by only a factor of 3 when pressure increases up to 15 MPa. The power efficiency of the actuator is also measured; it is in the range 10−3–10−4 and increases when pressure increases. Using a stacked actuator, consisting of 8 single actuators stacked on top of each other, a maximum strain of 5% is measured against atmospheric pressure.