Nanoparticles self assembly

Tian, L. and Hammond, P.T. Comb-dendritic block copolymers as tree-shaped macromolecular amphi-philes for nanoparticle self-assembly, Chem. Mater., 18, 3976, 2006. 

Arumugam P, Xu H, Srivastava S, Rotello VM. Bricks and mortar nanoparticle self-assembly using polymers. Polym Int 2007 56 461-466. 

Figure 6.9 A schematic representation of orthogonal process for nanoparticles self-assembly (a) a patterned sihcon wafer with Thy-PS and PVMP polymers fabricated through photolithography and (b) orthogonal surface functionahzation through Thy-PS/DP-PS recognition and PVMP/acid-nanoparticle electrostatic interaction. Reprinted with permission from Xu et al. (2006). Copyright 2006 American Chemical Society.

Srivastava S, Frankamp BL, Rotello VM. Controlled plasmon resonance of gold nanoparticles self-assembled with PAMAM dendrimers. Chem Mater 2005 17 487-490. 

One of the points made in Schwenz and Moore was that the physical chemistry laboratory should better reflect the range of activities found in current physical chemistry research. This is reflected in part by the inclusion of modem instrumentation and computational methods, as noted extensively above, but also by the choice of topics. A number of experiments developed since Schwenz and Moore reflect these current topics. Some are devoted to modem materials, an extremely active research area, that I have broadly construed to include semiconductors, nanoparticles, self-assembled monolayers and other supramolecular systems, liquid crystals, and polymers. Others are devoted to physical chemistry of biological systems. I should point out here, that with rare exceptions, I have not included experiments for the biophysical chemistry laboratory in this latter category, primarily because the topics of many of these experiments fall out of the range of a typical physical chemistry laboratory or lecture syllabus. Systems of environmental interest were well represented as well. 

Materials Nanoparticles, Self-Assembled Monolayers Supramolecular Systems, Liquid Crystals and Polymers... 

Tagawa, T., Manvell, M., Brown, N., et al. (2002). Characterisation of LMD viruslike nanoparticles self-assembled from cationic liposomes, adenovirus core peptide mu and plasmid DNA. Gene Then, 9(9), 564-576. 

Mi, F. L., Y. Y. Wu, et al. (2008). Oral delivery of peptide drugs using nanoparticles self-assembled by poly(gamma-glutamic acid) and a chitosan derivative functionalized by trimethylation. Bioconjug Chem 19(6) 1248-55. 

Figure 3. Schematic illustration of nanoparticle self-assembly via solvent evaporation.

One assembly example is polyethylenamine (PEI)-mediated self-assembly of FePt nanoparticles [56]. PEI is an all -NH-based polymer that can replace oleate/oleylamine molecules around FePt nanoparticles and attach to hydrophilic glass or silicon oxide surface through ionic interactions [52], A PEI/FePt assembly is readily fabricated by dipping the substrate alternately into PEI solution and FePt nanoparticle dispersion. Figure 10 shows the assembly process and TEM images of the 4 nm Fes8Pt42 nanoparticle self-assemblies on silicon oxide surfaces. Characterizations of the layered structures with X-ray reflectivity and AFM indicate that PEI-mediated FePt assemblies have controlled thickness and the surfaces of the assemblies are smooth with root mean square roughness less than 2 nm. 

Fig. 7 Illustration depicting molecular recognition based polymer-mediated nanoparticle self-assembly. Interparticle distance and corresponding blocking temperature (Tb) of hexanes induced precipitations and polymer mediated aggregates...

Sayle et al. (2008) also developed (Figure 9) a route exploiting the classical atomistic simulation to make combined studies of theoretical and experimental works. A typical selected system is ceria. Since the pair potential model based on electrostatic interaction and Buckingham short range presentations are often adequate to describe the fluorite structure of ceria, Sayle et al. explored the application of such models in nano-sized particles. A series of works have been reported on the assembly behaviors of nano-building blocks into complex nanostructures, including the ceria nanoparticles self assembly in ice mold (Karakoti... 

Biological systems provide numerous examples of self-assembled objects. Owing to the relatively weak interactions involved, a self-assembled structure is much more sensitive and responsive to its environment than a more rigid structure held together by covalent bonds. Unlike processes involving simple surfactants, polymers, and nanoparticles, self-assembly processes in biological systems are usually directional and functional and often lead to the formation of extremely complex structures. For example, the three-dimensional structure adopted by a protein in solution is critical to the protein s function, and this structure is determined by both strong (covalent) and weak... 

A broad view of principal findings and processes utilized for the development of oriented polymer morphologies has been presented. New trends toward the advancement of this topic are being developed within the realm of multidisciplinary research. Studies of order development in polymers have—for a few years already—transcended beyond traditional disciplines in chemistry and engineering. Genetically engineered polymers, nanoparticles, self-assembled molecules, supercritical fluids, and hybrids are some of the few areas that are now an integral part of macromolecular structural property relationship studies. 

Jana, N.R. (2004) Shape effect in nanoparticle self-assembly. Angew. Chem., 116, 1562-1566. 

A special case of nanoparticle self-assembly is the Janus particle. It was shown that Janus particles are considerably more active than homogeneous particles of comparable size and chemical nature and that the interfacial activity can be increased by increasing the amphiphilic character of the particles. Thus, the Janus particles show a significant advantage in the stabilization of emulsions and foams over homogeneous particles as they unify the Pickering concept and the amphiphilicity of a simple surfactant. 

Kutuzov S et al (2007) On the kinetics of nanoparticle self-assembly at liquid/liquid interfaces. Phys Chem Chem Phys 9(48) 6351—6358... 

Y. Wang, S. Gao, W.-H. Ye, H. S. Yoon, and Y.-Y. Yang, Co-delivery of drugs and DNA from cationic core-shell nanoparticles self-assembled from a biodegradable copolymer. Nat. Mat. 5, 791 (2006). 

Rana RK, Murthy VS, Yu J et al (2005) Nanoparticle self-assembly of hierarchically ordered microcapsule stmctures. Adv Mater 17(9) 1145-1150... 

Figure4.40 TEM images of 1-D ordered cobalt nanoparticles self-assembled in the magnetic fields of different strengths. Reproduced with permission from Ref [30] 2002, Elsevier Science.

Manufacturing Improvements for precision engineering new processes, and tools to manipulate matter at the atomic level nanopowders that are sintered into bulk materials with special properties that may include sensors to detect incipient failures and actuators to repair problems chemical-mechanical polishing with nanoparticles, self-assembling of structures from molecules bioinspired materials and biostructures... 

Ho, S., Kwak, S., Sohn, B., and Hyun, T. 2003. Design of TiOj nanoparticle self-assembled aromatic polyamide thin-fihn-composite (TFC) membrane as an approach to solve biofouling problem. Journal of Membrane Science 211 157-165. 

Kwak SY, Kim SH, and Kim SS, Hybrid organic/inorganic reverse osmosis (RO) membrane for bactericidal antifouling. 1. Preparation and characterization of TiOj nanoparticles self-assembled aromatic polyamide thin-film composite (TFC) membrane, Environmental Science and Technology 2001, 35, 2388-2394. 

Furthermore, the FT-IR analytical technique was ap>plied in analysis of surface of membranes interacted with other materials. For instance, Luo et. al., fabricated the SPES/Nano-Ti02 composite ultrafiltration membrane. In their studies, the Ti02 nanoparticle self-assembly on the SPES membrane surface was confirmed by X-ray photoelectron spectroscopy (XPS) and FT-IR spectrometer. When the nano-TiCb was self-assembled on the SPES membrane the absorption peak at 1243 cm-i attributes to the stretching vibration of the ether C-O-C bond in the SPES polymer shifted to 1239 cmri. The result of FT-IR spiectrometer effectively verified the self-assembly process of nano-Ti02 on the SPES membrane.P ... 

Mu S, Tang H, Wan Z, Pan M, Yuan R (2005) Au nanoparticles self-assembled onto Nafion membranes for use as methanol-blocking barriers. Electrochem Conunun 7 1143-1147... 

This method along with effect of nanoparticles self-assembly on the substrate paves the way for the preparation of stable nanoparticles dispersions and the formation of capacitor dielectric layers of thickness about 200 nm, which is ten... 

Decomposition of organometallic compounds with subsequent synthesis of nanostructures is often accompanied by the phenomenon of so-called self-assembly (Self-assembling) [335]. Last decade, many papers on nanoparticles self-assembly and self-organization have been published [336, 337]. Some of them belong to nanoferroics. 

---