Microfluidic deivices have increasing application as analytical systems

biomedical devices

tools for chemistry and biochemistry

and systems for fundamental research. Conventional methods of fabricating microfluidic devices have focused on etching in glass and silicon. Fabrication of microfluidic devices in poly (dimethylsiloxane) (PDMS) by soft lithography provides faster

less expensive routes than these conventional methods. These softlithographic methods are based on rapid prototyping and replica molding. At the same time

they are also more accessible for chemists and biologists to work under benchtop conditions because devices do not need to be fabricated in a cleanroom using soft lithography. This paper describes devices fabricated in PDMS for separations and patterning of biological material.