Micro-patterned Polymer Devices for Biological Applications

Polymers are increasingly being used to fabricate microfluidic devices for chemical and biological applications. In combination with silicon, glass or other materials, miniaturized components such as channels, mixers, pumps and valves can be realized using standard semiconductor processing technology. Electrical, magnetic or pressure actuation is frequently employed in these devices to manipulate fluid flow. Thus, complete "lab-on-chip" devices have been engineered with complex functionality for specific applications. In this talk, I will provide an overview of the polymer structures fabricated in our laboratory and their utility for research in the life sciences. Specifically I will outline the soft lithography process for realizing poly-dimethyl siloxane (PDMS) devices from SU8 photoresist masters. Then I will demonstrate four examples of micro-patterned PDMS devices studied in our laboratory: (1) Micro-reservoirs with induction heating for amplification of DNA using the polymerase chain reaction (PCR) on a small scale (2) Micro-channels for electrophoresis and controlled movement of cells (3) Micro-electrode patterns for controlled movement of liquid droplets, now known as "digital microfluidics" and (4) Micro-valves to trap micro-organisms for in-vivo imaging of neuronal activity.