Plasma Treatment of PDMS for Microfluidics

Plasma treatment of PDMS in microfluidic fabrication produces a permanent and irreversible bond between PDMS and glass, improving analyte flow within microfluidic channels.

PDMS (Polydimethylsiloxane) is by far the most popular material used in microfluidics research where it is deployed for rapid prototyping with minimal cost. PDMS, however, requires a surface treatment step in order to produce strong, conformal bonds between surfaces. Plasma treatment of PDMS increases hydophilic (-OH) groups on the PDMS surface which subsequently form strong covalent bonds (Si– O–Si) when brought together with glass. These covalent bonds form the basis of a practically inseparable seal between the layers.

Plasma Treatment of PDMS

  • Removal of hydrocarbon groups
  • Exposure of hydrophilic -OH groups
  • Improved bonding to PDMS and glass substrates
  • Improve analyte flow
  • Possibility of patterned surfaces with alternating hydrophilic/hydrophobic regions