Nanoparticle-induced self-assembly

Lin, J., Zhou, W., Kumbhar, A., Wiemann, J., Fang, J., Carpenter, E.E. and O Connor, C.J. (2001) Gold-coated iron (Fe-Au) nanoparticles Synthesis, characterization, and magnetic field-induced self-assembly./. Solid State Chem., 159, 26-31. 

Perez, J.M., Simeone, F.J., Saeki, Y., Josephson, L., and Weissleder, R. (2003) Viral-induced self-assembly of magnetic nanoparticles allows the detection of viral particles in biological media, J. Am. Chem. Soc. 125, 10192. Description of a viral nanosensor using iron oxide nanoparticles. This group is at Harvard Medical School. 

So far as passivated Ag nanoparticles concerns, diere is known a convenient one-pot preparation method (14). Silver salt of carbonic acid such as myristote is heated at about 620 K without any solvent. Pyrolytically reduced Ag atoms then self-assemble to form metal clusters of about 5 nm in diameter, which are surrounded by remaining Ag myristate to form organo-passivated Ag nanoparticles with yield of 70 %. This type of self-organization may be called reaction-induced self-assembly. 

Xu, J., Xia, J., Lin, Z. Evaporation-induced self-assembly of nanoparticles from a sphere-on-flat geometry. Angew. Chem. Int. Ed. 119, 1892-1895 (2007)... 

Ou C, Su C, Jeng U, Hsu S. Characterization of biodegradable polyurethane nanoparticles and thermally induced self-assembly in water dispersion. Acs Appl Mater Interfaces April 23, 2014 6(8) 5685-94. 

Figure 6.8 One-pot synthesis of shell-fijnctionalized polymeric nanoparticles by ROMP-induced self-assembly. (Reproduced from Ref. [60].)...

Wen, T, et al. Novel electrochemical sensing platform based on magnetic field-induced self-assembly of Fe304 Polyaniline nanoparticles for clinical detection of creatinine. Biosens. Bioelectron. 56C, 180-185 (2014)... 

Figure 2.12 (a) Schematic of evaporation-induced self-assembly of nanoparticle building blocks and block copolymer templates leading first to porous hybrid films and then to fully inorganic films after thermal treatment (b) SEM image of a particle-based mesoporous... 

Fig. 17 Synthesis of multipod-like silica/polymer particles by NMP-mediated polymerization-induced self-assembly (PISA) of block copolymers by means of a PEO-based brush-type macroalkoxyamine initiator previously adsorbed at the surface of colloidal silica nanoparticles. Reproduced from [99] with permission from the American Chemical Society...

Ferguson, Hawkett and coworkers have pioneered the field of polymerization-induced self-assembly by employing RAFT emulsion polymerization of acrylic acid and n-butyl acrylate in aqueous media [39]. This approach led to in situ self-assembled nanoparticles formed by an amphiphilic block copolymer. First, acrylic acid was polymerized in the water phase to yield a water-soluble macro-RAFT agent, followed by the polymerization of hydrophobic n-butyl acrylate. At the completion of the polymerization, self-stabilized micelle-like PAA-b-PnBA particles of number-average diameter of 60.3 nm were obtained. When polymerization was continued by feeding of another hydrophobic monomer, styrene, spherical core-shell particles composed of poly(acrylic acid)-b-poly(butyl acrylate)-b-polystyrene triblock copolymer were formed [40]. 

The polymerization-induced self-assembly is a facile, efficient, and reproducible strategy for preparation of families of polymeric nanoparticles having various morphologies via a one-pot process. Direct preparation of the block copolymer aggregates in the dispersion and emulsion polymerizations at high concentration of sohds provides the possibihty for large-scale industrial production. Preferentially, the polymerization-induced self-assembly should be conducted in aqueous media at quantitative monomer conversion. 

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