AVS 52nd International Symposium
    Biomaterial Interfaces Monday Sessions
       Session BI-MoP

Paper BI-MoP6
Micropatterned Surface Modification of Polydimethylsiloxane via UV-Initiated Graft Polymerization of Acrylates

Monday, October 31, 2005, 5:00 pm, Room Exhibit Hall C&D

Session: Biomaterial Interfaces Poster Session
Presenter: N. Patrito, University of Western Ontario, Canada
Authors: N. Patrito, University of Western Ontario, Canada
S. Chiang, University of Western Ontario, Canada
P.R. Norton, University of Western Ontario, Canada
N.O. Petersen, National Institute for Nanotechnology, Canada
Correspondent: Click to Email
Polydimethylsiloxane (PDMS) is a transparent, elastic polymer that is becoming an increasingly popular substrate for the fabrication of microfluidic devices. The widespread application of PDMS-based microfluidic devices to bioanalytical research has, however, been limited by the material's extreme hydrophobicity and surface inactivity. A desire to improve the wettability and biocompatibility of PDMS has resulted in a large body of research into the surface modification of siloxane polymers. One promising method for the permanent modification of PDMS is the covalent linkage of hydrophilic polymers on its surface via UV-initiated graft polymerization (UV-GP). Combining UV-GP with photolithographic techniques, poly(acrylic acid) and poly(methacrylic acid) patterns are successfully grafted onto PDMS thin films with micron-scale fidelity. Contact angle measurements, AFM imaging, surface roughness analyses, and XPS spectra confirm the presence of the grafted layers and provide insights into their morphology and surface coverage. This report also examines the effects of the graft materials on the adhesion and proliferation of common experimental cell lines, CV-1 and A-431. AFM images illustrate the improved attachment and growth of both cell types on the PAA and PMAA patterned substrates. These observations confirm the utility of UV-GP as a means of improving PDMS biocompatibility. They also demonstrate the amenability of the UV-GP technique to precise patterning, providing researchers with an effective, efficient means of localizing bio-adhesion on a variety of substrates.