Interaction of the adhesive protein Mefp-1 and fibrinogen with methyl and oligo(ethylene glycol)-terminated self-assembled monolayers

The interaction of fibrinogen and Mefp-1, the adhesive protein of the common blue mussel Mytilus edulis, with methyl- and oligo(ethylene oxide) (OEG)-terminated self-assembled monolayers (SAMs) has been investigated by Fourier Transform Infrared Reflection (FT-IRAS) analysis. The measurements on the hydrophobic surfaces show that the underlying SAM is structurally undisturbed when the proteins adhere. Mefp-1 is used as an attachment factor (Cell-Tak(TM)) in cell cultures and in biomedical applications, and it is of interest to determine if OEG-terminated surfaces are inert towards Cell-Tak-mediated cell adhesion. We find that, when Langmuir transfer of a protein film at the liquid/air interface is avoided, the moderately hydrophilic hydroxyhexa (ethylene oxide) and methoxytri(ethylene oxide) undecanethiolate SAMs prepared on Au substrates are protein resistant. The inertness of the OEG-terminated surfaces does not depend on any specific protein present in solution, but rather appears to be a general phenomenon that is independent of the specific structure or chemistry of the macromolecule.