Figure 1.
Representation of a self-assembled monolayer (SAM) of alkanethiolates on the surface of gold. The sulfur atoms of the alkanethiolates coordinate to the gold surface and arrange the alkyl chains in a close-packed layer. The properties of the SAM are determined by the terminal functional group of the precursor alkanethiol. The figure shows alkanethiolates that are terminated in the methyl group and in the tri(ethylene glycol) group. The latter have proven important because they are effective at preventing the non-specific adsorption of protein.