Growth-Induced Wrinkles and Dotlike Patterns of a Swollen Fluoroalkylated Thin Film by the Reaction of Surface-Attached Polymethylhydrosiloxane.

The design of hydrophobic surfaces requires a material which has a low solid surface tension and a simple fabrication process for anchoring and controlling the surface morphology. A generic method for the spontaneous formation of robust instability patterns is proposed through the hydrosilylation of a fluoroalkene bearing dangling chains, R = CF(CH)-, with a soft polymethylhydrosiloxane (PMHS) spin-coated gel polymer (0.8 μm thick) using Karstedt catalyst.

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°.

Interface of covalently bonded phospholipids with a phosphorylcholine head: characterization, protein nonadsorption, and further functionalization.

Surface anchored poly(methylhydrosiloxane) (PMHS) thin films on oxidized silicon wafers or glass substrates were functionalized via the SiH hydrosilylation reaction with the internal double bonds of 1,2-dilinoleoyl-sn-glycero-3-phosphorylcholine (18:2 Cis). The surface was characterized by X-ray photoelectron spectroscopy, contact angle measurements, atomic force microscopy, and scanning electron microscopy. These studies showed that the PMHS top layer could be efficiently modified resulting in an interfacial high density of phospholipids.