Thiols, self-assembled monolayers

Nakagawa, O. S., Ashok, S., Sheen, C. W., Martensson, J. and Allara, D. L. GaAs interfaces with octadecyl thiol self-assembled monolayer structural and electrical properties. Japanese Journal of Applied Physics, Part 1 30, 3759 (1991). 

Humblot V, Yala JF, Thebault P et al. (2009) The antibacterial activity of Magainin I immobilized onto mixed thiols self-assembled monolayers. Biomaterials 30 3503-3512... 

The formal potential, E0/, contains useful information about the ease of oxidation of the redox centers within the supramolecular assembly. For example, a shift in E0/ towards more positive potentials upon surface confinement indicates that oxidation is thermodynamically more difficult, thus suggesting a lower electron density on the redox center. Typically, for redox centers located close to the film/solution interface, e.g. on the external surface of a monolayer, the E0 is within 100 mV of that found for the same molecule in solution. This observation is consistent with the local solvation and dielectric constant being similar to that found for the reactant freely diffusing in solution. The formal potential can shift markedly as the redox center is incorporated within a thicker layer. For example, E0/ shifts in a positive potential direction when buried within the hydrocarbon domain of a alkane thiol self-assembled monolayer (SAM). The direction of the shift is consistent with destabilization of the more highly charged oxidation state. 

Sportsman, K.S., Bluhm, E.A., and Abney, K.D., Removal of actinides from acidic solution via carrier-mediated facihtated transport across mesoporous substrates with nanoengineered surfaces Thiol self-assembled monolayers with D(tBu)4>D(iBu)CMPO ligands. Sep. Sci. Tech., 2005, 40 709-723. 

Reimers, J.R., Zhang, J.D., and Ulstrup, J. (2009) Scanning tunneling microscopic observation of adatom-mediated motifs on gold-thiol self-assembled monolayers at high coverage. Journal of Physical Chemistry C, 113, 19601-19608. 

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