Carbon nanotube with dendrimers

Subrahmanyam KS, Vivekchand SRC, Govindaraj A, Rao CNR (2008) A study of graphenes preprtfed by different methods characterization, properties and solubilization. J Mater Chem 18 1517-1523 Sun J-T, Hong C-Y, Pan C-Y (2011) Surface modification of carbon nanotubes with dendrimers or hyperbianched polymers. Polym Chem 2 998-l(X)7... 

There is currently considerable interest in processing polymeric composite materials filled with nanosized rigid particles. This class of material called "nanocomposites" describes two-phase materials where one of the phases has at least one dimension lower than 100 nm [13]. Because the building blocks of nanocomposites are of nanoscale, they have an enormous interface area. Due to this there are a lot of interfaces between two intermixed phases compared to usual microcomposites. In addition to this, the mean distance between the particles is also smaller due to their small size which favors filler-filler interactions [14]. Nanomaterials not only include metallic, bimetallic and metal oxide but also polymeric nanoparticles as well as advanced materials like carbon nanotubes and dendrimers. However considering environmetal hazards, research has been focused on various means which form the basis of green nanotechnology. 

Newkome-type dendrons were attached to the carbon scaffold of SWCNTs and MWCNTs by defect group functionalization [108], First- and second-generation amine dendrons such as those depicted in Fig. 1.5 were condensed with the carboxyl groups of purified and opened SWCNTs and MWCNTs according to the car-bodiimide technique [108], These CNTderivatives can be expected to combine the characteristics of carbon nanotubes with those of dendrimers, potential building blocks for supramolecular, self-assembling and interphase systems. 

H.C. Choi, W. Kim, D. Wang, H. Dai, Delivery of Catalytic Metal Species onto Surfaces with Dendrimer Carriers for the Synthesis of Carbon Nanotubes with Narrow Diameter Distribution, Journal of Physical Chemistry B 106, 12361, 2002. 

Hirsch A, Vostrowsky O (2001) Dendrimers with Carbon Rich-Cores. 217 51-93 Hirsch A, Vostrowsky O (2005) Functionalization of Carbon Nanotubes. 245 193-237 Hissler M, Dyer PW, Reau R (2005) The Rise of Organophosphorus Derivatives in p-Conjugated Materials Chemistry. 250 127-163 Hiyama T, Shirakawa E (2002) Organosilicon Compounds. 219 61-85 Holmberg K, see Hager M (2003) 227 53-74... 

Like the currently popular area, called nanoscience , the field of supramolecular chemistry has rather hazy boundaries. Indeed, both areas now share much common ground in terms of the types of systems that are considered. From the beginning, electrochemistry, which provides a powerful complement to spectroscopic techniques, has played an important role in characterizing such systems and this very useful book goes considerably beyond the volume on this same topic by Kaifer and Gomez-Kaifer that was published about 10 years ago. Some of the classic supramolecular chemistry topics such as rotaxanes, catenanes, host-guest interactions, dendrimers, and self-assembled monolayers remain, but now with important extensions into the realms of fullerenes, carbon nanotubes, and biomolecules, like DNA. 

Fig. 33.2. Schematic picture of the methods of immobilization of the aptamers (A) chemisorption. Biotinylated aptamer is immobilized on a surface covered by (B) avidin, (C) neutravidin and (D) avidin on a surface of poly(amidoamine) dendrimers (PAMAM). (E) Aptamer is immobilized on carbon nanotubes activated by Tween 20 (it is partially adapted from Ref. [39] with permission of American Chemical Society).

Carbon-based sorbents are relatively new materials for the analysis of noble metal samples of different origin [78-84]. The separation and enrichment of palladium from water, fly ash, and road dust samples on oxidized carbon nanotubes (preconcentration factor of 165) [83] palladium from road dust samples on dithiocarbamate-coated fullerene Cso (sorption efficiency of 99.2 %) [78], and rhodium on multiwalled carbon nanotubes modified with polyacrylonitrile (preconcentration factor of 120) [80] are examples of the application of various carbon-based sorbents for extraction of noble metals from environmental samples. Sorption of Au(III) and Pd(ll) on hybrid material of multiwalled carbon nanotubes grafted with polypropylene amine dendrimers prior to their determination in food and environmental samples has recently been described [84]. Recent application of ion-imprinted polymers using various chelate complexes for SPE of noble metals such as Pt [85] and Pd [86] from environmental samples can be mentioned. Hydrophobic noble metal complexes undergo separation by extraction under cloud point extraction systems, for example, extraction of Pt, Pd, and Au with N, A-dihexyl-A -benzylthiourea-Triton X-114 from sea water and dust samples [87]. 

To summarize, in this chapter we have discussed medium-sized supermolecules with unique shapes. Some of them (fullerenes and carbon nanotubes) are found in nature, while others (dendrimers, rotaxanes and catenanes) can be synthesized via artificial molecular design. As seen from palladium-based molecular capsule formation, spontaneous association can sometimes also provide highly sophisticated supramolecular structures. Indeed, as... 

Siqueira Jr, J.R., et al. Penicillin biosensor based on a capacitive field-effect structure functionalized with a dendrimer/carbon nanotube multilayer. Biosens. Bioelectron. 25(2), 497-501 (2009)... 

P-cyclodextrin incorporated multiwalled carbon nanotube and gold NPs-polyamide amine dendrimer nanocomposites combining with water-soluble chitosan derivative A molecularly imprinted sensor for the detection of chlortetracycline [255]... 

In an attempt to develop synthesis of QDs using dendrimers as template, amino-polyester dendrons were used for t plating and stabilizing of CdS nanoparticles on the surface of single-wall carbon nanotubes (SWNTs) (Fig. 6.19). Attachment to SWNTs can be achieved by focal group while the interior space of the dendron serves for nanoparlicle formation. The obtained CdS nanoparticles with diameter of 1.4 nm were stable for more than 90 days at 25°C. It has been suggested that these characteristics may be useful for fabricating molecular electronic devices [55]. 

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