Edge amphiphile

The edge amphiphile character is even more pronounced in the glycosylated derivative of cholic acid which crystallizes in the form of planar bilayers with the axial carbohydrate moieties in the centre. Large channels containing organized water molecules and potassium counter-ions are thus formed (Figure 7.18). 

EDGE AMPHIPHILES AS PORES IN AND HARPOONS AS DISRUPTORS OF LIPID MEMBRANES... 

Figure 2.7.3 A disulfone bolaamphiphile forms vesicles, which are perforated by a tetraamino edge amphiphile containing two carboxylate end groups. The amine presumably occurs in the conformation given. It assembles in vesicle membranes to form pores that let iron(II) ions pass the membrane. Large organic ions close the pore. EDTA in the bulk water phase cannot pass through the pore and sucks iron ions out of the vesicle, (From Fuhrhop et al., 1988.)...

Cholesterol has, in general, the effect of making fluid membrane structures manageable and selective. Edge amphiphiles form charmels in vesicle membranes containing cholesterol. It has been shown that efficient pore formation for... 

Figure 9.6.10 A synthetic heme pocket. Both the peptide and the porphyrin react as bolaamphiphiles and as edge amphiphiles.

Figure 5.4. An example of variegated cells that may be used in modeling an amphiphile molecule with different trajectory rules for the different types of edges...

Figure 7. SEM and XRMA microphotographs of palladium catalysts supported on the amphiphilic resin made by DMAA, MTEA, MBAA (cross-linker) [30]. Microphotographs (a) and (b) show an image and the radial palladium distribution after uptake of [Pd(OAc)2] from water/acetone the precursor diffuses only into the outer layer of the relatively little swollen CFP after reduction the nanoclusters remain close to the edge of the catalyst beads. Microphotographs (c) and (d) show the radial distribution of sulfur and palladium, respectively, after uptake of [PdCU] from water after reduction palladium is homogenously distributed throughout the catalyst particles. This indicates that under these conditions the CFP was swollen enough to allow the metal precursor to readily penetrate the whole of polymeric mass. (Reprinted from Ref. [30], 2005, with permission from Elsevier.)...

In the proposed model, Figure 7.24, the edges of the aromatic side-walls of the receptor amphiphile form the floor and the roof of the rectangles. A consequence of this architecture is that the rectangles in some cases organize themselves further, tilted on their edges,... 

The relationship between the lifetime rof amphiphile bilayer and the hole edge energy % is described by Eqs. (3.123), (3.124) and (3.126). This relationship is applicable to bilayers both free of or containing foreign bodies if in the latter case % is described by a numerical factor accounting for the ability of the foreign body to stimulate hole formation [403]. The latter case is of special interest, since in enables the rupture of BLMs containing proteins or... 

The chiral SOs bear either a strongly electron-deficient aromatic group (rt-acid), e.g. 3,5-dinitrophenyl, or an electron-rich aromatic moiety (rt-base), e.g. naphthyl, placed for face-to-face and/or face-to-edge 7i-it-interaction with complementary sites within the SA molecule. If these molecular features are not available in the SA, they have to be introduced by achiral derivatization. This concept includes also rt-amphiphilic SOs. 

The most stable and diversified porphyrin assemblies were received from protoporphyrin IX derivatives. It is characteristic that no crystal structure of an amphiphilic porphyrin is known. Crystal structures of esters have frequently been solved (see section 7.5), but protoporphyrin IX or similar porphyrins with a hydrophilic and a hydrophobic edge withstood all attempts at crystallization. This may be because they prefer to occur in curved fibrous assemblies. 

Figure 6.20 Lipid multilayers in cast films may be doped with water-soluble or amphiphilic porphyrins. The hydrophobic macrocycle of protoporphyrin derivatives (—) with one hydrophilic edge integrates into the hydrophobic membrane, but their orientation is not fixed. Water-soluble porphyrins with four sulfo-nated phenyl rings at the methine bridges are oriented parallel to the film surface. The ordering of the hydrophobic bilayer can also be controlled by azo-dyes which are covalently bound to the hydrophobic chains of the lipids, hereC,H,r-C6H4-N=N—C6H4-C,oH2o—N(CHs)sBr.

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