Self supramolecular structures

Due to its unique chemical composition and structure, DNA can interact with a plethora of chemical structures via numerous types of bonds. This property ultimately defines the ability of DNA fragments to serve as the building blocks in the complex three-dimensional self-assembled structures. Following we Ust four major types of polymer/DNA interactions that can lead to formation of supramolecular structures ... 

Bikadi Z, Zsila F, Deli J, Mady G, and Simonyi M. 2002. The supramolecular structure of self-assembly formed by capsanthin derivatives. Enantiomer 7 67-76. 

Attempts have recently been made to link the RNA world with the lipid world. Two groups involved in RNA and ribozyme research joined up with an expert on membrane biophysics (Szostak et al., 2001). They developed a model for the formation of the first protocells which takes into account both the most recent experimental results on replication systems and the self-organisation processes of amphiphilic substances to give supramolecular structures. 

Organoclay materials with higher-order organization can also be prepared by template-directed methods involving self-assembled supramolecular structures. In this approach, preformed organic architectures in the form of tubes, fibers, hollow shells, gyroids, helicoids, and so on are transferred into hybrid materials exhibiting structural hierarchy, complex form and ordered mesoporosity [47-55]. For example,... 

Molecular calculations provide approaches to supramolecular structure and to the dynamics of self-assembly by extending atomic-molecular physics. Alternatively, the tools of finite element analysis can be used to approach the simulation of self-assembled film properties. The voxel4 size in finite element analysis needs be small compared to significant variation in structure-property relationships for self-assembled structures, this implies use of voxels of nanometer dimensions. However, the continuum constitutive relationships utilized for macroscopic-system calculations will be difficult to extend at this scale because nanostructure properties are expected to differ from microstructural properties. In addition, in structures with a high density of boundaries (such as thin multilayer films), poorly understood boundary conditions may contribute to inaccuracies. 

Some antimony and bismuth xanthates tend to self-assemble through M - -S secondary bonds into supramolecular structures. 

Chalcogen-Halogen Secondary Bonds in Self-Assembling of Supramolecular Structures... 

Currently the main interest in template reactions lies in their key role in the controlled synthesis or the self-assembly of a variety of supramole-cular entities (449). One needs a combination of intuition, conjecture, and serendipity (450) a recent example of successfully combining serendipity and rational design is provided by the silver(I)-promoted assembly of one-dimensional stranded chains (451). One also needs an understanding of mechanism in order to optimize the selection and design of building blocks and templates for the generation of yet more sophisticated supramolecular structures references cited in this present review contain at least some kinetic or mechanistic information or speculation. Template routes to interlocked molecular structures have been reviewed (452), while a discussion of switching by transition metal contains a little about the kinetics and mechanisms of this aspect of template... 

The rational synthesis of peptide-based nanotubes by self-assembling of polypeptides into a supramolecular structure was demonstrated. This self-organization leads to peptide nanotubes, having channels of 0.8 nm in diameter and a few hundred nanometer long (68). The connectivity of the proteins in these nanotubes is provided by weak bonds, like hydrogen bonds. These structures benefit from the relative flexibility of the protein backbone, which does not exist in nanotubes of covalently bonded inorganic compounds. 

Self-replication, in supramolecular chemistry, 24 49-50 Self-rising flours, 26 281-282, 283 Self-sensing, in rheometers, 21 737 Self-supporting structures, artificial graphite in, 12 745 Self-warming baby milk bottle... 

Model of a supramolecular structure of polymolecular ensembles or clusters, determined by interaction and mutual arrangement of the forming molecules. At this level, the specific mechanisms of supramolecular chemistry, including molecular recognition, self-assembly, etc. [4] can be allocated. In most cases, it is possible to limit this area to objects with the sizes under 1 to 2 nm, since further increase in the sizes admits application of statistical concepts like phase and interphase surface. 

Surfactants are therefore effective solubilizers that can exfoliate CNTs by physical adsorption, which occurs at interfaces, allowing self-assembling into supramolecular structures [50]. 

Tsuda K, Dol GC, Gensch T, Hofkens J, Latterini L, Weener JW, MeijerEW, De SchryverEC. Fluorescence from azobenzene functionalized poly(propylene imine) dendrimers in self-assembled supramolecular structures. J Am Chem Soc 2000 122 3445-3452. 

Fig. 4 Free energy diagram for the two possible situations in enzyme-triggered formation of supramolecular assembly. Left. The enzyme-catalysed reaction and self-assembly process are both favoured independently and therefore uncoupled. Right. Enzyme-triggered self-assembly under thermodynamic control formation of the building blocks is thermodynamically unfavoured in isolation and occurs in reversible fashion when coupled to a sufficiently stable self-assembled structure formation...

Bonaccio, S., Cescato, C., Walde, R, and Luisi, P. L. (1994b). Self-production of supramolecular structures. In Liposomes from Lipidonucleotides and from Lipidopeptides, eds G. R. Fleischaker et al. Kluwer Academic, pp. 225-59. 

Luisi, P. L. (1994). In Self-Reproduction of Supramolecular Structures, Proceedings from the Maratea Symposium, eds. G. Heischacker, S. Colonna and P. L. Luisi. Kluwer. 

The central part of cell walls is a membrane consisting of complex self-assembled structures with built-in channels that execute complicated functions, e.g., the transport of ions briefly discussed in Section 5.3.4). Creating artificial membranes mimicking the functioning of biological membranes is one of the important tasks of supramolecular chemistry. 

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