Thin phosphatidylcholine films as background surfaces with further possibilities of functionalization for biomedical applications.

Non-specific adsorption is a crucial problem in the biomedical field. To produce surfaces avoiding this phenomenon, we functionalized thin (7-180 nm) poly(methylhydrosiloxane) (PMHS) network films at room temperature (≈20°C) with phospholipids (PL) bearing a phosphorylcholine head. Regardless of their mode of preparation (casting or immersion), all surfaces appeared to be very hydrophilic with a captive air-bubble contact angle stabilized around 40°. The thin films were protein-repellent in phosphate saline buffer pH 7.4 according to analysis by normal scanning confocal fluorescence. Neither was any adsorption or spreading of l-α-phosphatidylcholine liposomes on such films observed. In addition, amino functional groups could be easily attached to the surface remaining available for further functionalization.