Low-density self-assembled monolayers

While in the mentioned work on PABA on a charged silver electrode also the adsorption degree of the molecules was controlled by surface charge, Lahann et al. showed a concept in which molecules immobilized as a low-density self-assembled monolayer on a gold surface were electrically stimulated to undergo conformational transitions between a hydrophilic and a hydrophobic state (Lahann et al., 2003). Such a surface wetting switch may then be used to immobilize, for example, enzymes, as was discussed in the previous section. This is an example of switching both the orientation and the activity of adsorbed molecules. 

High-Density and Low-Density Self-Assembled Monolayers... 

Figure 6.1 Low-density self-assembled monolayer on gold - response to an external electric potential. Lahann et ai.

Peng, D.K. and Lahann, J. (2007) Chemical, electrochemical, and structural stability of low-density self-assembled monolayers. Langmuir, 23, 10184-10189. 

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