Nanoparticle assemblies multicomponent

Figure 13.8 The assembly of multicomponent nanostructures by using complementary guest- and host-functionalized nanoparticles (a). The nanoparticle assembly from small to large (b) and large to small nanoparticles (c) by supramolecular interactions.

Hammond et al. reported the self-organization of SK>2 and polystyrene nanoparticles on a jlCP patterned polyelectrolyte substrate (Fig. 13.16).28 The multicomponent nanoparticle assembly was driven by spatial electrostatic and hydrophobic... 

Fan, J Boettcher, S.W., and Stucky, G.D. (2006) Nanoparticle assembly of ordered multicomponent mesostructured metal oxides via a versatile sol—gel process. Chem. Mater., 18 (26), 6391-6396. 

NIL patterns were also used for the assembly of nanoparticles via supramole-cular host-guest interactions.95 The NIL-patterned substrate was functionalized with CD SAMs via a three-step synthesis process. The fabrication of 3D nanostructures was achieved by the alternating assembly of multivalent guest-functionalized dendrimers and CD-fnnctionalized Au nanoparticles.88 This methodology can be applied to various nanoparticles, regardless of their size and core material. For instance, CD-functionalized silica and polystyrene nanoparticles were adsorbed onto NIL-patterned CD SAMs with preadsorbed guest-fnnctionalized dendrimers.60 92 Recently, Huskens et al. demonstrated the supramolecular LbL assembly of 3D multicomponent nanostructures of nanoparticles by alternating assembly steps of complementary ferrocenyl-functionalized silica nanoparticles and different kinds of host-fnnctionalized nanoparticles (see Fig. 13.8).66... 

To demonstrate the versatility of this approach, we created binding patterns of different size and allowed different nanoparticles to form superstructures (Fig. 15.7c). Again a fraction of nanoparticles was inactive, and the thermal drift caused a slight distortion of the red structure. However, even the scale bar could be trustfully assembled. The expansion of this approach towards multicomponent structures is straightforward since there exist couplers with orthogonal affinities that can be linked to the transfer DNA. Whereas the assembly of planar nanoparticle structures of arbitrary design can easily be assembled this way, an expansion into the third dimension appears challenging but achievable. 

DNA molecules are the most frequently used building blocks for assemblies of various dimensions between nanometers and micrometers [1,2]. The negative charge in phosphate backbone of DNA molecules is favourable for fastening metal nanoparticles and, consequently, for creating multifunctional and multicomponent nanostructures. 

Park J, Fouche LD, Hammond PT (2005) Multicomponent patterning of layer-by-layer assembled polyelectrolyte/nanoparticle composite thin films with controlled alignment. Adv Mat 17(21) 2575-2579... 

Multicomponent composites built by LbL assembly may consist not only of nanocrystals but also of nanowires, biomolecules, dyes, and functional polymers. In addition, metal nanoparticles may be employed with potential applications in the fields of drug delivery and biodetection, energy harvesting, optical signal processing, and emission enhancement or quenching [70, 93]. 

CuFe204 nanoparticles have also been used as magnetically separable catalysts for the multicomponent assembly of 1,2,3-triazoles in water (Scheme 4.9) (Kumar et at, 2012). 

Kim, B.S. and Taton, T.A. (2007) Multicomponent nanoparticles via self-assembly with cross-linked block copolymer surfactants. Langmuir, 23,2198-2202. 

Capitalizing on multicomponents, organic-inorganic hybrid nanocomposite materials have exhibited a synergistic effect due to properties generated by individual counterparts that may be useful for various technological applications. The surface modification of nanoparticles by functional monolayers of polymer sheUs provides a means of functionalization of nanocomposites and further tunable surface properties that may allow their covalent attachment, self-assembly, and organization on surfaces. 

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