Self-assembly approach

Adamantane can be used to construct peptidic scaffolding and synthesis of artificial proteins. It has been introduced into different types of synthetic peptidic macrocycles, which are useful tools in peptide chemistry and stereochemistry studies and have many other applications as well. Introduction of amino acid-functionalized adamantane to the DNA nanostmctures might lead to construction of DNA-adamantane-amino acid nanostmctures with desirable stiffness and integrity. Diamondoids can be employed to constmct molecular rods, cages, and containers and also for utilization in different methods of self-assembly. In fact, through the development of self-assembly approaches and utilization of diamondoids in these processes, it would be possible to design and constmct novel nanostmctures for effective and specific carriers for each dmg. 

The optical and electrochemical properties of porphyrins make these chromophores useful building blocks for the synthesis of electro- and photoactive polymers. Two types of linear polymers have been constructed using the self-assembly approach homo-polymeric assemblies and hetero- or shish kebab polymers. 

The advantage of the self-assembly approach is its inherent possibility for combinatorial ligand library generation through mixing of two differ-... 

Molecular imprinting can be accomplished in two ways (a), the self assembly approach and (b), the preorganisation approach3. The first involves host guest complexes produced from weak intermolecular interactions (such as ionic or hydrophobic interaction, hydrogen bonding) between the analyte molecule and the functional monomers. The self assembled complexes are spontaneously formed in the liquid phase and are sterically fixed by polymerisation. After extraction of the analyte, vacant recognition sites specific for the imprint are established. Monomers used for self assembly are methacrylic acid, vinylpyridine and dimethylamino methacrylate. 

Oriented CNT self-assembly route The self assembly approach relies on the alignment of short SWNTs that were cut by oxidative treatments and ultrasonication [43,... 

J. Veinot, H. Yan, S. Smith, J. Cui, Q. Huang, and T.J. Mark Fabrication and Properties of Organic Light-Emitting Nanodiode Arrays. Nano Lett. 2,333 (2002). Y. Xia, B. Gates, and Z.-Y. Li Self-Assembly Approaches to Three-Dimensional Photonic Crystals. Adv. Mater. 13, 409 (2001). 

In the spontaneous self assembly approach to synthesis, the inherent kinetic lability of the Fe/Mo/S system allows for the fcnmation of various thermodynamically stable, heteronuclear products that, as of now, do not include one with the desir le Fe/Mo/S atom ratio of 6-7 1 6-8. 

Modification of the gold surface in the self-assembly approach proceeds after dipping the gold electrode into the solution... 

Several laboratories have described systems by which synthetic linear peptide chains self-assemble into desirable secondary and tertiary structures. One self-assembly approach has been the creation of a peptide-amphiphile, whereby a peptide head group has the propensity to form a distinct structural element, while a lipophilic tail serves to align the peptide strands and induce secondary and tertiary structure formation, as well as providing a hydrophobic surface for self-association and/or interaction with other surfaces. The preparation of a dialkyl ester tail first involves the acid-catalyzed condensation of H-Glu-OH with the appropriate fatty acid alcohol to form the dialkyl ester of H-Glu-OH a typical example is shown in Scheme 7. The assembly of peptide-amphiphiles with mono- and dialkyl ester tails is shown in Scheme 8. A series of studies have demonstrated that triple-helical and a-helical protein-like molecular architecture is stabilized in the peptide-amphiphile 44,63-65 ... 

We wanted to explore the limits of the self-assembly approach for the synthesis of well-defined structures with nanoscale dimensions by further increasing the size of the assemblies. Our group has shown that calix[4]arenes diametrically substituted with two melamine units at the upper rim are very good platforms for the formation of double rosette assemblies. 

While technically simpler than the covalent approach, the self-assembly approach creates more heterogeneous sites and also requires templates with specific functional groups.8 Since sol-gel chemistry is aqueous based, H-bonding interactions are significantly weaker compared to the conventional organic polymerization methods. Often, hydrophobic effects and ionic interactions are utilized. A number of other examples of the noncovalent approach to imprinting in sol-gel-derived materials are provided in recent reviews.5 17 In the sections below, the focus will be on some of the newer aspects of small molecule imprinting in silica that involve the use of chiral templates... 

Figure 12. Dual-Patterning or guided self-assembly approaches to SOMA disks. The array ordering length scale of 1-10 pm is replicated around the circumference of a disk by topographic or chemical guide patterns.

Diamondoid networks represent just one example of the types of architecture that can be generated in a rational manner using the modular self-assembly approach. The remainder of this chapter will focus upon the diversity of simple architectures that are accessible using crystal engineering strategies, many of which have no precedent in minerals yet are afforded via one-pot reactions and commercially available components. 

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