Surface engineering of microfluidic systems for cellular biochips

In this paper, we describe a rapid and cost-effective hydrophilic surface modification method for PDMS microsystems that is both durable and biocompatible. The method involves a combination of an oxygen plasma treatment followed by coating the activated surfaces with a hydrophilic and biocompatible polymer. In this case, poly(vinylpyrrolidone) (PVP) is used to increase the surface energy of PDMS microchannels and render them hydrophilic. Contact angle experiments show that the surface of the PDMS remains hydrophilic for an extended period of time under dry conditions. Uses for microfluidic and cell chip applications are demonstrated.