Self-assembly assisted

Addadi and Weiner (1999) have concisely and critically reviewed these various strategies and have added their own variant - the use of biological templates, for instance bacterium surfaces to assist self-assembly. Here, self-assembly and biomimetics join forces productively. 

Two-dimensional planar interpenetrating networks have been formed using the spacer ligand 2,2 -bis-l,6-naphthyridine with a zinc salt.274 Helicate structures have been synthesized which rely heavily on non-covalent interactions in the metal-assisted self-assembly process in solution.275... 

Nadagouda, M.N. and Varma., R.S. (2006) Green and controlled synthesis of gold and platinum nanomaterials using vitamin B2 density-assisted self-assembly of nanospheres, wires and rods. Green Chemistry. 8 516-518. 

Historically, the first multivalent glycoconjugate obtained by metal-assisted self-assembly was described in 1994 by Sakai and Sasaki (Fig. 35).267 The methodology was based on the trimerization of unsymmetrical Bipy-GalNAc (307) induced by the presence of Fe(II) salts, to give the tridentate Fen(bipy-GalNAc)3 cluster 308 as a mixture of four diastereomeric isomers (A-fac, A-fac, A-mer, and A-mer). 

Redox enzymes have been assembled in a monolayer on the solid surface by a potential-assisted self-assembling method as well as a thiol-gold selfassembling method. These enzymes are electronically communicated with the solid substrate through a molecular interface of conducting polymer and a covalently bound mediator. Electron transfer type of enzyme sensors have been fabricated by the self-assembling methods. 

Two different types of self-assembling processes are described. The one is a potential-assisted self-assembly of redox enzymes on the surface of an electrode. The potential-assisted self-assembly is followed by electrochemical... 

Potential-assisted Self-assembly of Enzymes on the Electrode Surface... 

Fig. 7 Procedure of the potential-assisted self-assembly of enzyme molecules...

Y. Yin, Y. Lu, B. Gates, and Y. Xia Template-Assisted Self Assembly A Practical Route to Complex Aggregates of Monodispersed Colloids with Well-Defined Sizes, Shapes and Structures. J. Am. Chem. Soc. 123, 8718 (2001). 

Y. Xia, Y. Yin, Y. Lu, and J. Me Lellan Template-Assisted Self-Assembly of Spherical Colloids into Complex and Controllable Structures. Adv. Funct. Mater. 13, 907 (2003). 

Spatially confined self-assembly has been further confirmed by localizing ther-molysin on certain areas of a PEGylated surface. Upon immersion of this modified surface into a solution containing self-assembling precursors, nanostructures were formed in the vicinity of the enzyme, as observed through congo-red staining (Fig. 7c) [21]. Thus, enzyme-assisted self-assembly allows for construction of supramolecular polymers with spatiotemporal control, i.e. where and when they are required. 

WiUiams RJ, Smith AM, Colhns R, Hodson N, Das AK, UUjn RV (2009) Enzyme- assisted self-assembly under thermodynamic control. Nat Nanotechnol 4 19-24... 

Yin W, Zhang MS (2003) Characterization of nanosized Tb-MCM-41 synthesized by the sol-gel-assisted self-assembly method. J Alloys Compounds 360 231-235... 

Applications of the TASP approach are then considered for such aspects as four-helical bundles (Section 13.1.2.4.2)J4 The details of structures and synthetic routes for the preparation of the bundles are described. Other chain assemblies and applications are discussed (Section 13.1.2.5) including metal-ion assisted self assemblies, disulfide linkages in the formation of four-helical bundles (Section 13.1.2.5.2), multiple antigenic peptide systems (Section 13.1.2.5.4), and templates constructed from a trialdehyde template by reductive amination to form a three-helical bundle (Section 13.1.2.5.5))5 ... 

Metal Ion Assisted Self-Assembly into Triple-Helix Bundle Proteins... 

Template-Assisted Self-Assembly of Colloidal Particles by Wrinkled Surfaces 87... 

Self-assembly can be divided into a number of classes 1. strict self-assembly, 2. irreversible self-assembly, 3. precursor modification followed by self-assembly, 4. self-assembly with post-modification, 5. assisted self-assembly, 6. directed self-assembly, 7. self-assembly with intermittent processing. 

Xia, Y., Yin, Y., Lu, Y. McLellan, J. Template-assisted self-assembly of spherical colloids into complex and controllable structures. Adv. Funct. Mat. 13, 907—918 (2003). 

Balzer, F. and Rubahn, H.-G. (2001) Dipole-assisted self-assembly of light-emitting p-np needles on mica. Applied Physics Letters, 79, 3860-2. 

Lu Y., Fan H., Stump A., Ward T. L., Rieker T. and Brinker C. J., Aerosol-assisted self-assembly of mesostructured spherical nanoparticles. Nature 398 (1999) pp.223-226. 

Jami, A.K., Kishore, P.V.V.N., and Baskar, V. (2009) Functionalised -diketone assisted self-assembly of a hexanuclear yttrium oxo-hydroxo cluster. Polyhedron, 28, 2284—2286. 

Assisted and directed self-assembly are derivatives of thermodynamic and irreversible self-assembly in which an external agent or template either prevents the formation of non-functional intermediates (assisted self-assembly), or stabilizes key intermediates or products (directed self-assembly). The external agent need not appear in the final product. Numerous examples of directed self-assembly, in particular, have been described. Such systems provide important new pathways to novel structures. However, the factors controlling such processes are often not easily rationalized. 

Figure 4.38 Patterned zeolite films prepared by using a) soft-lithography. Reproduced with permission from [140], Copyright (2000) American Chemical Society b) convection-assisted self-assembly. Reproduced with permission from [143]. Copyright (2001) American Chemical Society) c) gel-casting. Reproduced with permission from [141], Copyright (2001) Royal Society of Chemistry...

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