Nanoparticles template

Another method to synthesize hollow nanocapsules involves the use of nanoparticle templates as the core, growing a shell around them, then subsequently removing the core by dissolution [30-32]. Although this approach is reminiscent of the sacrificial core method, the nanoparticles are first trapped and aligned in membrane pores by vacuum filtration rather than coated while in aqueous solution. The nanoparticles are employed as templates for polymer nucleation and growth Polymerization of a conducting polymer around the nanoparticles results in polymer-coated particles and, following dissolution of the core particles, hollow polymer nanocapsules are obtained. 

Prior to use as a nanoparticle template, the p subunits were genetically modified by adding cysteine residues at different solvent exposed sites to yield two mutant variations of the... 

Galvanic replacement reactions with small silver nanoparticies have been studied in detail by Lu et al. [132], They found that a complete gold shell did not form on the surface of each individual silver nanoparticle template. Instead, the replacement reaction resulted in the formation of alloy nanorings and nanocages from multiply-twinned silver nanoparticies of decahedral or icosahedral shape. 

Prior to use as a nanoparticle template, the p subunits were genetically modified by adding cysteine residues at different solvent exposed sites to yield two mutant variations of the P subunits. The two variations consisted of p subunits with exposed 28 amino acid loops and p subunits with these amino acid loops deleted. These p subunits were then assembled into chaperonin proteins upon Mg +/ATP binding and crystallized into a reactive protein template with a ring of thiol groups that protruded into the protein pore to different extents (3 nm and 9 nm pore diameters). ... 

X. Luo, A. J. Killard, A. Moirin, and M. R. Smyth, Electrochemical preparation of distinct polyaniline nanostructures by surface charge control of polystyrene nanoparticle templates, Chem. Commun., 3207-3209 (2007). 

Figure 14.9 The application of porous PAN films and composites to the sensing of nitrite. Scale 7 gm (A) Porous film ofpoly(aniline) formed from the in situ electrochemical synthesis in the presence of WO nm polystyrene nanoparticle templates. (B) Enhanced electrocatalysis of concentrations of 50 gM nitrite in 0.7 M HCI at+ 50 mVvs. Ag/AgCI of the nanocomposite film (d) compared to classy carbon (a), pre-treatedglassy carbon (b) and bulk PANI [85]. (Reprinted with permission from Chemistry A European journal, Nanocomposite and nanoporous polyaniline conducting polymers exhibit enhanced catalysis of nitrite reduction by X. Luo, A.j. Killard and M.R. Smyth, 13, 2138-2143. Copyright (2007) Wiley-VCH)...

Meltzer, S., Resch,R., et al. Fabrication of Nanostructures by Hydroxylamine Seeding of Gold Nanoparticle Templates. Langmuir,17(5), 1713-1718(2001). 

Viruses are similar to biomolecular templates because the viral capsid is in fact a complex composed of protein subunits. Viruses coupled with nanoparticles can be used as building blocks to form nanoparticle assemblies or virus assemblies of two and three dimensions can be used as templates. Virus is advantageous as a building block because identical viruses can be produced in large amounts at low cost, and nanoparticles templated by viruses generally have a high monodispersity. Viruses may have inherent self-assembly, for example, nanowires mineralized... 

Wang W, Luo C, Shao S et al (2010) Chitosan hollow nanospheres fabricated from biodegradable poly-D,L-lactide-poly(ethylene glycol) nanoparticle template. Eirr J Pharm Biopharm... 

In this chapter, we provide an overview of the recent research and development in the preparation, characterization, and application of novel porous carbons using both the endotemplate and the exotemplate methods. A discussion of zeolite templates for microporous carbons is followed by that of ordered mesoporous silica templates for OMCs, nanoparticle templates for mesoporous carbons, sol-gel processed porous carbons, self-assembled colloidal crystal templates for ordered macroporous carbons, and colloidal sphere templates for hollow carbon spheres, as well as other templating approaches to preparing carbon nanostructures. Then,... 

FIGURE 2.32 FESEM images of (a) TiOj nanoparticles, (b) carbon-TiOj composite, (c) a porous carbon prepared using TiOj nanoparticle template, and (d) TEM image of the carbon. (From Su, F. and Zhao, X.S. Unpublished work, 2006b.)... 

FIGURE 2.33 Proposed mechanism for the formation of nanopores in carbon using a colloidal silica nanoparticle template. (From Pang, J., Hu, Q., Wu, Z., Hampsey, J.E., He, J., and Lu, Y. Micropor Mesopor Mater lA 73-78, 2004. With permission.)... 

C. Chauvierrea, R. Manchandab, D. Labarrec, C. Vauthier, M.C. Mardena, and L. Leclerc, Artificial oxygen carrier based on polysaccharides-poly(alkylcyanoacrylates) nanoparticles templates. Biomaterials, 31 (23), 6069-6074,2010. 

---