Integrated Electrochemical Pumping and Dosing System Using Phaseguide Techniques with Inherent Implemented Valving and Metering

For lab-on-a-chip applications the defined transport of fluids is mandatory. On-chip metering and aliquoting are challenging and usually achieved with complicated systems so far. This paper describes an integrated electrochemical pump (ECP) and dosing system benefitting from phaseguide techniques for pumping defined batches of biological liquids. This innovative concept combines electrochemical actuation principles with concepts for passive valving and metering, for liquid handling methods and for contamination free transport of various media between microfluidic chambers. We achieve high flexibility, reproducibility, reliability and accuracy without using membranes. The electrolysis actuation and metering principle are implemented in a microfluidic system in a simple and robust way resulting in constant flow rates tested between 7 µl/min and 60 µl/min. Two AA batteries are sufficient to supply the constant low power consumption between 2.7 mW to 11.2 mW of the pump. Microfluidic problems during the filling and emptying of micro-chambers and controlled metering are solved by adaptation of the phaseguide technology for liquid control. Euglena gracilis is pumped in growth medium as proof of concept for pumping cell cultures. In order to simulate viscous biological solutions, pumped liquids also involved glycerine solutions. Furthermore, it is demonstrated that DNA solutions can be pumped without observable loss in concentration and without heating.