| The functionalization of surfaces with the phosphorylcholine (PC) moiety has been found to confer greatly increased thromboresistance. The PC moiety is the most abundant zwitterionic group in the phospholipids contained in the outer leaflet of lipid bilayer membranes of various organisms.; Poly(dimethylsiloxane) (PDMS) has good intrinsic biocompatibility and may benefit even further from PC incorporation. PC-terminated dimer, pentomer, and 378-mer were synthesized in ca. 50% overall yields. The water contact angles revealed that the dimer (&thetas;a = 0–2°) and pentomer (&thetas;a = 10°) were very hydrophilic while the 378-mer (&thetas;a = 62°) showed an increase in wetting compared to PDMS. X-ray photoelectron spectroscopy (XPS) showed that the PC termini were buried beneath the outermost surface layer. Secondary-ion mass spectrometry (SIMS) revealed the presence of the PC group at the dimer and pentomer surfaces but not at the 378-mer surface.; Self assembled monolayers (SAMs) are widely used as model surfaces for membranes, biorecognition studies, and sensors. A SAM surface of PC groups would permit facile surface characterization of this moiety. To achieve this, 11-thioundecanyl-1-phosphocholine and 6-thiohexanyl-1-phosphocholine were synthesized in ca. 60% yield from the corresponding α,ω-thioalcohols. The compounds were used to make SAMs on gold. The surfaces were hydrophilic, exhibiting advancing water contact angles of 30° and 45°, respectively. |
