Self-Assembled Monolayers of Alkanethiolates Presenting Mannitol Groups Are Inert to Protein Adsorption and Cell Attachment

Abstract

This paper reports on a model surface that is inert in biological fluids and that is important for studies in biointerfacial science. A self-assembled monolayer (SAM) terminated in the mannitol group was found to prevent the adsorption of proteins and the attachment of cells. Surface plasmon resonance spectroscopy showed that the mannitol-terminated SAM prevented the adsorption of several proteins and was indistinguishable from a SAM presenting tri(ethylene glycol)groups. In a second set of experiments, monolayers were patterned into circular regions of hexadecanethiolate with the surrounding area terminated in the mannitol group in order to evaluate the inert surface for patterning cell attachment. 3T3 fibroblasts, attached to the circular regions, proliferated to occupy these regions completely and remained patterned on these regions for 25 days. The use of oligo(ethylene glycol)-terminated SAMs, by contrast, showed a loss in fidelity of the pattern after one week in culture. The mannitol-terminated monolayers significantly extend the time course for maintaining patterned cells and will have immediate utility in fundamental and applied biology.