Self-assembled nanostructure application

Dendrimers are being used as host molecules, catalysts, self-assembling nanostructures analogs of proteins, enzymes, and viruses and in analytical applications including in ion-exchange displacement chromatography and electrokinetic chromatography. 

In this chapter we study the overview of the various naturally and artificially prepared self-assembled nanostructures which are currently very important and in demand in biomedical applications, for example, bone tissues, natural laminated composites present in sea shells, peptide chain arrays and their derivatives and cell membranes are naturally self-assembled materials. And Langmuir—Blodgett films, surfactant-directed nonporous materials, and molecularly directed films, composites, nanombes, nanofibrils, nanowires, spherical vesicles, and template-assisted growth are artificially prepared self-assembled nanostructures. Here we discuss in brief the synthesis of those nanostructures which exist in nature and are prepared artificially to fulfill certain requirements (Figure 2.1). 

Joshi et al., in Chapter 2, Self-assembled nanostructure preparation and applications, discuss about the fabrication of nanostructures from biological building blocks. The self-assembly of such nanostructures is a spontaneous process by which molecules/nanophase entities will materialize into organized aggregates. Many biomolecules, such as proteins and peptides, can interact and self-assemble into highly ordered supramolecular architectures including nanotubes, nanofibrils, nanowires, spherical vesicles, and hybrids, the subsequent improvement of their properties and their possible applications. 

Molecular self-assembly has been recognized as a powerful approach to designer soft materials with a nanoscopic structural precision [llj. However, self-assembled nanostructures are inherently subject to disruption with heating and exposure to solvents. The HBC nanotubes are not exceptional. Thus, for practical applications of the nanotubes, one has to consider postmodification of their nanostructures for covalent connection of the assembled HBC units. Because the inner and outer surfaces of the nanotubes are covered with TEG chains, incorporation of a polymerizable functionality into the TEG termini allows for the formation of surface polymerized nanotubes with an enhanced morphological stability. 

Device application and integration. It is clear that self-assembled nanostructures hold great promise for future applications. Nanorod structures have been studied for nearly a decade now however, very httle progress has been made in the implementation of these structures into/as devices. Further work is required in order to integrate these structures into devices. Future work in our laboratory will study the catalytic efficiency of RUO2 nanorods in a microthruster device. 

Applications of self-assembled nanostructures for bone tissue engineering... 

In the past decade, there are a number of promising self-assembled nanostructures with attractive properties and great potential for bone tissue engineering applications. These nanostructures of interest are in the forms of hydrogels or scaffolds consisting of nanotubular or nanofibrous materials fabricated by the aforementioned methods. Here, some typical self-assembled nanostractures for bone tissue engineering are inhoduced. 

The scope of this chapter also covers recent studies that have attempted to shed light on the possible fragmentation of these inverted type self-assembled nanostructures for forming nanoparticlulate formulations attractive for food and pharmaceutical applications. These nanostructured aqueous dispersions (mainly cubosomes, hexosomes, and micellar cubosomes) in which the submicron-sized dispersed particles envelope distinctive well-defined self-assembled nanostructures can be utilized in different applications owing to their low viscosity as conqjared to the corresponding non-dispersed bulk liquid crystalline phases and their biological relevance. 

Many reviews, books, proceedings, and chapters have been published on the topic. Serious LLS users should consult References (1) and (2) and other books, rather than proceedings or articles, as reference materials. In particular, the first monograph on the theoretical aspects of dynamic LLS (6) is highly recommended because it remains as the best source reference. In this article there is concentration on experimental detail. Often, static and dynamic LLS are used separately generally, polymer chemists are more familiar with static LLS and only use dynamic LLS to size particles, whereas polymer physicists are not custom to precise static LLS measurements and sample preparation. This seriously limits their application. This article specially deals with this problem by using several typical examples to show how static and dynamic LLS can be combined to extract more information, such as the characterization of molar mass distribution, estimation of composition distribution of a copolymer, the adsorption/grafting of polymer chains on colloidal particle surfaces, and the self-assembled nanostructure of block copolymers. 

Recent progress in nanotechnology has a positive effect on the field of drug delivery. In particular, self-assembled nanostructures are extremely important for therapeutic and delivery applications. Their size, high loading capacity, and reversible character are major assets for the controlled release of therapeutics. 

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