Effect of surface nanostructuring of PDMS on wetting properties, hydrophobic recovery and protein adsorption

Poly(dimethylsiloxane) (PDMS) is an inherently hydrophobic material widely used in microfluidic and lab-on-a-chip devices. In this work, plasma-induced surface nanostructuring of PDMS in SF6 was explored as a means to control surface wettability modified in SF6 and O-2 plasmas. In addition, rapid hydrophobic recovery was achieved with a process consisting of washing with de-ionized water and thermal treatment of the surfaces. Immobilization of biotinylated-BSA (b-BSA) on treated surfaces was also investigated. The results indicate that intense surface topography leads to significant delay in hydrophobic recovery of the surface and an enhanced capacity for protein adsorption. (C) 2008 Elsevier B.V. All rights reserved.