Poly(dimethylsiloxane)-coated sensor devices for the formation of supported lipid bilayers and the subsequent study of membrane interactions

Abstract

The development of smooth hydrophilic surfaces that act as substrates for supported lipid bilayers (SLBs) is important for membrane studies in biology and biotechnology. In this article, it is shown that thin films of poly(dimethylsiloxane) (PDMS) formed on a sensor surface can be used as a substrate for the deposition of reproducible and homogeneous zwitterionic SLBs by the direct fusion of vesicles. Poly(dimethylsiloxane) solution (1% w/v) was spin coated on Love acoustic wave and surface plasmon resonance devices to form a thin PDMS layer. Acoustic, fluorescence, and contact angle measurements were used for the optimization of the PDMS film properties as a function of plasma etching time; parameters of interest involve the thickness and hydrophilicity of the film and the ability to induce the formation of homogeneous SLBs without adsorbed vesicles. The application of PDMS-coated sensor devices to the study membrane of interactions was demonstrated during the acoustic and fluorescence detection of the binding of melittin and defensin Crp4 peptides to model supported lipid bilayers.