Host-guest system

Fig. 11.6 The SC24/halide system. (Figure adapted from Lybrand T P, ] A McCammon and G Wipff 1986. Theoretical Calculation of Relative Binding Affinity in Host-Guest Systems. Proceedings of the National Al adeniy of Sciences USA 83 833-835.)...

The main supramolecular self-assembled species involved in analytical chemistry are micelles (direct and reversed), microemulsions (oil/water and water/oil), liposomes, and vesicles, Langmuir-Blodgett films composed of diphilic surfactant molecules or ions. They can form in aqueous, nonaqueous liquid media and on the surface. The other species involved in supramolecular analytical chemistry are molecules-receptors such as calixarenes, cyclodextrins, cyclophanes, cyclopeptides, crown ethers etc. Furthermore, new supramolecular host-guest systems arise due to analytical reaction or process. 

Enoki, T., Novel carbon-based host-guest systems. In Supercarbon, Synthesis, Properties and Applications, ed. S. Yoshimura and R. P. H. Chang. Springer-Verlag, Heidelberg, 1998, pp. 129 138. 

Badertscher, M., Welti, M., Portmann. P., and Pretsch, E. Calculation of Interaction Energies in Host-Guest Systems. 136, 17-80 (1986). 

Borovkov VV, Inoue Y (2006) Supramolecular Chirogenesis in Host-Guest Systems Containing Porphyrinoids. 265 89-146... 

Host-guest systems made from dendritic materials have potential in the areas of membrane transport and drug delivery [68, 84, 85]. In a recent report [136] Tomalia and coworkers investigated structural aspects of a series of PAM AM bolaamphiphiles (e.g., 50) with a hydrophobic diamino do decane core unit. Fluorescence emission of added dye (nile red) was significantly enhanced in an aqueous medium in the presence of 50 unlike the cases when 51 and 52 were added (Fig. 23). Addition of anion surfactants to this mixture generated supramolecular assemblies which enhanced their ability (ca.by 10-fold) to accommodate nile red (53). Further increase in emission was noted by decreasing the pH from the normal value of 11 for PAMAM dendrimers to 7. At lower pH values the... 

Another elimination triggered tetrafold anionic domino process has been reported by Risch and coworkers [301]. These authors synthesized polycyclic bipyridine scaffolds as 2-585 (Scheme 2.132) which are potentially useful as ligands for host-guest systems or interesting building blocks for supramolecular applications [302]. The process combines an amine elimination from 2-584 and a Michael addi-... 

In host-guest systems based on electron donor/ acceptor interactions, association/dissociation can be driven by redox processes so that it is possible to design electrochemical switches than can be used to control energy- and electron-transfer processes. 

G. Vamvounis and S. Holdcroft, Enhancing solid-state emission from conjugated polymers via self-forming host-guest systems, Adv. Mater., 16 716-719, 2004. 

Further investigation of this host-guest system showed not only that different guests could be incorporated in one host, but also that guest molecules of different size could be liberated in a shape selective fashion [168, 169]. 

Single-molecule spectroscopy of a dendrimer-based host-guest system. Chem Eur J 7 4126-4133... 

This chapter shows that zeolite L is a very suitable host for the arrangement of a wide variety of chromophores. The structure of zeolite L is such that the formation of non-fluorescent dimers inside the channels can be prohibited and chromophores can be aligned in a certain direction. We have shown that this host-guest system can be used to make very efficient nanoscale two-directional photonic antenna systems. A broad spectral absorption range can be achieved by using several different cationic and neutral dyes. 

Thus, the Platonic and Archimedean solids not only provide a means for host design, but a way in which to maximize chemical information, allowing the chemist to simplify the structures of complex molecular frameworks and, in effect, engineer host-guest systems. 

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