Introduction of Amino Groups on Poly(dimethylsiloxane) Surface Using Low-pressure Nitrogen-based Inductively Coupled Plasma

Abstract

Poly(dimethylsiloxane) (PDMS) has been widely used as a fabrication material of biomicrosystem devices which are called as lab-on-a-chip or μ-TAS. Generally, the devices when used in biological applications require some surface modification for the control of hydrophilicity and nonspecific adsorption and selective attachment of functionalized biomolecules on their surfaces. In this paper, we report the introduction of amino gourps on PDMS surfaces using low-pressure inductively coupled plasmas. Nitrogen/hydrogen (N₂+H₂) mixed plasma and pure N₂ plasma system were examined. In the case of pure N₂ plasmas, surface atomic concentration of N reached approximately 10 atom%, and formation of primary amino groups was confirmed by XPS and ATR-FTIR measurement. Furthermore, attachment of biotinylated-PEG was demonstrated via active-ester method.