Artificial mimics

Interest in the development of synthetic schemes and approaches to create molecular recognition elements has blossomed during the past half century for a number of reasons. In contrast to biologically based receptors, artificial mimics have the potential advantages of being less costly, more stable, and better able to withstand harsher conditions.7-12 Furthermore, synthetic methodologies can be used to create receptors for molecules for which an artificial receptor does not exist. These designer materials have enormous potential in catalysis, clinical and pharmaceutical applications, chemical sensors, separation science, and electronics.7-12... 

Several channel architectures have been considered when designing artificial mimics. The most obvious biologically inspired method is to prepare extended helical molecules in an attempt to reproduce the channels either within the helix or where the molecules meet. A small number of systems have been designed using this... 

The arrangement of the proteins buried in the lipid bilayer allows them to respond dynamically to external stimuli. These characteristics of the membrane proteins are related to their various functions. In the following sections, the excellent functions expressed by these membrane proteins are explained and their artificial mimics are introduced. 

Another way to transport ions is to provide them with a polar channel—in cells, a protein pore embedded in the membrane with a lipophilic outer face and a hydrophilic inner face. Artificial mimics of ion chaimels include peptide nanotubes—cyclic peptide molecules designed to stack into cylindrical channels by the suitable placement of hydrogen-bonding groups around their edges (Fig. 

Fig. 6.8 Water molecules sit in two different positions (WG, WA) in the binding site of the ionotropic glutamate receptor protein and help two different molecules to bind the natural neurotransmitter glutamate (Glu) and an artificial mimic called AMPA (From Ref. [61]. 2011 American Chemical Society)...

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