Fabrication of polyurethane microfluidic channels and their surface modification for blood contacting application

In this study, we report two new fabrication processes for making thin, transparent, flexible and biocompatible polyurethane (PU)-based microfluidic devices. We detail not only the fabrication of microchannels but also their bonding, integration of fluidic interconnections as well as surface modification with hydrophilic polyethylene oxide (PEO) to improve their biocompatibility in blood contacting applications. These processes produced microchannels with high transparency (96% of glass in visible spectrum), high bond-strength (326.4kPa) and low fibrinogen (Fg) adsorption (80% reduction), which is critical for its anti-thrombotic property. Based on these results, PU could serve as an effective alternative to PDMS in many blood contacting biomedical applications. Copyright © (2011) by the Chemical and Biological Microsystems Society.