Membrane mimetic chemistry

(organic chemistry) The study of processes and reactions that have been developed by using information obtained from biological membrane systems.

The study of processes and reactions whose developments have been inspired by the biological membrane. Faithful modeling of the biomembrane is not an objective of membrane mimetic chemistry. Rather, only the essential components of natural systems are recreated from relatively simple, synthesized molecules. (The term membrane mimetic is more restrictive than the term biomimetic. Biomimetic chemistry is directed at the mechanistic elucidation of biochemical reactions and at the development of new compounds modeled on specific biological systems.)

Various surfactant aggregate systems have been used in membrane mimetics.

Surfactants (detergents) contain distinct hydrophobic (apolar) and hydrophilic (polar) regions. Depending on the chemical structure of their hydrophilic polar head groups, surfactants can be neutral, positively charged, or negatively charged.

Aqueous micelles are spherical aggregates, 4–8 nanometers in diameter, formed dynamically from surfactants in water above a characteristic concentration, the critical micelle concentration. See also Micelle.

Monomolecular layers are formed by spreading naturally occurring lipids or synthetic surfactants, dissolved in volatile solvents, over water in a trough. The polar head groups of the surfactants are in contact with water, the subphase, while their hydrocarbon tails protrude above it. See also Monomolecular film.

Other systems used in membrane mimetics are multilayer assemblies (Langmuir-Blodgett films), bilayer lipid membranes, and vesicles prepared by sonication from naturally occurring lipids. See also Sonochemistry.

Membrane mimetic chemistry has become a versatile chemical tool. Applications of compartmentalization of reactants in membrane mimetic systems involve altered reaction rates, products, stereochemistries, and isotope distributions. Monolayers and organized multilayers can be employed profitably as molecular electronic devices. Opportunities also exist for using different surfactant aggregates with polymeric membranes for the control and regulation of reverse osmosis and ultrafiltration. See also Surfactant; Ultrafiltration.