Gold-pyridine monolayers

Similar SCS-Pd(II) complexes have also been used to prepare isolated nanometer-sized objects within a decanethiol self assembled monolayer on gold [88]. In this chemistry, the thioether derivative of a pyridine complex of the SCS-Pd(ll) complex 22 was first prepared and immobilized on gold as part of a self assembled monolayer. Then the much better phosphine ligand... 

The self-assembling complex [Os(bpy)2(dipy)Cl](PF6) (bpy is 2,2 -bipyridine, dipy is trimethylene-4,4 -bipyridine abbreviated as Osdipy Fig. 4(C)) chemisorbs onto platinum and gold surfaces through a dangling pyridine ring with a free energy of adsorption of the order of-50 kJ/mol to form well-ordered, redox-active monolayers... 

Other nitrogen-containing compounds, such as pyridines, also adsorb on the Au(lll) surface . Electrodeposition at a positive potential ca 0.4 V) leads to formation of complete layers. 2,2 -Bipyridine forms more stable monolayers as compared to those of 4,4 -bipyridine because both nitrogen atoms of the former compound could interact with the gold surface . Aliphatic nitriles do not form well-packed monolayers on gold. The compounds with more than 10 methylene units form layers only 6-8 A thick, and contact angles of these layers are ca 90-94°, significantly lower than those expected for a well-packed alkane layer ca 114°) . ... 

Zhang, Z., T. Imae, H. Sato, A. Watanabe, and Y. Ozaki (2001). Surface-enhanced Raman scattering and surface-enhanced infrared absorption spectroscopic studies of a metaUoporphyrin monolayer film formed on pyridine self-assembled monolayer-modified gold. Langmuir 17, 4564. 

Fig. 19 Molecular recognition between barbituric acid derivatives (25) and a diamino-pyridine-based receptor functionalized alkanethiol (26) on the surface of a self-assembled thiolate monolayer on a gold film...

Another application for photoswitchable enzymes attached to gold surfaces is the cytochrome c-mediated biocatalysed reduction of O2 by cytochrome oxidase, using a functional pyridine-nitrospiropyran photoiso-merisable mixed monolayer electrode (see Sect. 6.1, Fig. 39) [8,16,17]. 

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