Surface properties, fibrinogen adsorption, and cellular interactions of a novel phosphorylcholine-containing self-assembled monolayer on gold

A novel synthetic route for the preparation of a phosphorylcholine terminat ed thiol is presented. The new molecule was characterized by FTIR and NMR a nd was used to prepare one- and two-component monolayers rich in phosphoryl choline. The new surfaces had an intermediate hydrophilicity based on their sessile contact angles, but dynamic contact angle measurements showed that the surfaces became completely wettable when in contact with water. Ellips ometric measurements revealed that the molecules extended toward the monola yer-air interface similar to well-studied monolayers prepared from methyl- or hydroxyl-terminated thiols. Angle-resolved XPS survey measurements verif ied that phosphorus, nitrogen, and oxygen were situated closer to the monol ayer-air interface, a conclusion also supported by angle-resolved C Is meas urements. crazing-angle FTIR data indicated a less ordered structure for al l the PC-containing monolayers than that of a methyl-terminated SAM. Fibrin ogen adsorption and neutrophil adhesion on the new surfaces were significan tly lower than on gold and on CH3-terminated SAMs. Bacterial adhesion was n ot found to vary significantly between the surfaces examined.