High-density fabrication of normally closed microfluidic valves by patterned deactivation of oxidized polydimethylsiloxane Academic Article uri icon


MeSH Major

  • Dimethylpolysiloxanes
  • Microfluidic Analytical Techniques


  • The use of polydimethylsiloxane (PDMS) in microfluidic devices is extensive in academic research. One of the most fundamental treatments is to expose PDMS to plasma oxidation in order to render its surface temporarily hydrophilic and capable of permanent bonding. Here, we show that changes in the surface chemistry induced by plasma oxidation can spatially be counteracted very cleanly and reliably in a scalable manner by subsequent microcontact printing of residual oligomers from a PDMS stamp. We characterize the surface modifications through contact angle, atomic force microscopy, X-ray photoelectron spectroscopy, and bond-strength measurements. We utilize this approach for negating the bonding of a flexible membrane layer within an elastomeric valve and demonstrate its effectiveness by integration of over one thousand normally closed elastomeric valves within a single substrate. In addition, we demonstrate that surface energy patterning can be used for "open microfluidic" applications that utilize spatial control of surface wetting.

publication date

  • February 21, 2011



  • Academic Article



  • eng

Digital Object Identifier (DOI)

  • 10.1039/c0lc00112k

PubMed ID

  • 21132212

Additional Document Info

start page

  • 738

end page

  • 42


  • 11


  • 4