Synthetic bilayer membranes

Kunitake, T. (1992) Synthetic bilayer-membranes - molecular design, self-organization, and application. Angew. Chem. Int. Ed., 31, 709-726. 

Murakami, Y., Kikuchi, J., Hayashida, O. Molecular Recognition by Large Hydrophobic Cavities Embedded in Synthetic Bilayer Membranes. 175, 133-156 (1995). 

Kunitake, T. and Okahata, Y. (1977) Totally synthetic bilayer membrane. Journal... 

The conformational fixation and spatial organization of the catalytic group are important features of the enzyme active site. However, they are not realized by the use of conventional surfactant micelles. Synthetic bilayer membranes are better organized than surfactant micelles. Thus highly organized catalytic centers may be prepared in the future from synthetic bilayer systems. 

The self-assembling character of bilayer membranes is demonstrated by the formation of free-standing cast films from aqueous dispersions of synthetic bilayer membranes. The tendencies for association are sufficiently strong to allow the addition of guest molecules (nanoparticles, proteins, and various small molecules) to these films where the connective forces are secondary in nature and not primary. Synthetic polymer chemists have made use of these self-assembling tendencies to synthesize monolayer films. In particular, a monomer that contains both reactive groups and hydrophobic and hydrophilic areas is cast onto an appropriate template that self-assembles the monomer, holding it for subsequent polymerization. Thus, a bilayer structure is formed by... 

Molecular Recognition by Large Hydrophobic Cavities Embedded in Synthetic Bilayer Membranes... 

A biomembrane is an excellent example of supramolecular assemblies, in which various functional molecules are structurally organized for molecular recognition. In order to develop artificial supramolecular systems capable of mimicking biomembrane functions, it seems important to investigate molecular recognition by macrocyclic hosts embedded in synthetic bilayer membranes. 

The existence of the hydrophobic effect [14] in the formation of micelles, liposomes and other aggregates in water has been recognized and elaborately studied for several decades. Detergents, lipids and many derivatives made from them have been extensively studied and there are numerous reviews which document these in greater detail [15]. Synthetic bilayer membranes (BLMs) have been studied for the past three decades by using a variety of physical techniques [16]. Hydrophobic interaction has also been utilized for the design of hosts that bind guest molecules in water [17]. 

Intrinsic to ionic surfactants and amphiphiles are solvophihc (or ionophilic) groups. We were therefore interested in learning whether the simple dialkylammonium bromides (2C,jN, n = 12, 14 Figure. d) that belong to the original family of synthetic bilayer membranes [10] form a bilayer in ionic liquids. Amphiphiles 2C N" were dispersed in three ionic hquids (Schemes 11.1-11.2) by ultrasonication (concentrations, 10 mM). While 2C12N+ as homogeneously dispersed in the conventional... 

Okahata Y, Lim HJ, Nakamura G, and Hachiya S. A large nylon capsule coated with a synthetic bilayer membrane. Permeability control of NaCl by phase transition of the dialkylammonium bilayer coating. J. Am. Chem. Soc. 1983 105 4855. 

Tanaka, Y. Schroit, A.J. Calcium/phophate-induced immobilization of fluorescent phophatidylserine in synthetic bilayer membranes inhibition of lipid transfer between vesicles. Biochemistry 1986, 25, 2141-2148. 

Up until 1977, the non-covalent polymeric assemblies found in biological membranes rarely attracted any interest in supramolecular organic chemistry. Pure phospholipids and glycolipids were only synthesized for biophysical chemists who required pure preparations of uniform vesicles, in order to investigate phase transitions, membrane stability and leakiness, and some other physical properties. Only very few attempts were made to deviate from natural membrane lipids and to develop defined artificial membrane systems. In 1977, T. Kunitake published a paper on A Totally Synthetic Bilayer Membrane in which didodecyl dimethylammonium bromide was shown to form stable vesicles. This opened the way to simple and modifiable membrane structures. Since then, organic chemists have prepared numerous monolayer and bilayer membrane structures with hitherto unknown properties and coupled them with redox-active dyes, porous domains and chiral surfaces. Recently, fluid bilayers found in spherical vesicles have also been complemented by crystalline mono-... 

Cavities Embedded in Synthetic Bilayer Membranes. 175 133-156 Nagle DG, see Gerwick WH (1993) 167 117-180 Nakamura E,see Kuwajima I (1990) 155 1-39... 

Okahata, Y, Tanamachi, S., Nagai, M., and Kunitake, T., Synthetic bilayer membranes prepared from diaUcyl amphiphiles with nonionic and zwitterionic head groups, J. Colloid Interf. ScL, 82, 401 17, 1981. 

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