Nano reactor

Figure l.n Hexapus, a multi-polar amphiphile providing a supramolecular structure [55. Similar types of multi polar amphiphiles were used as nano-reactors for changing the course of reactions [56]. 

A strong surface charge on the halloysite tubules has been exploited for designing nano-organized multilayers using the layer-by-layer (LbL) method of Lvov et al. [8,13,14]. The lumen of the halloysite has been used as an enzymatic nano-reactor by Shchukin et al. [15] The biocompatible nature of the halloysite was... 

Control of the particle size while retaining precise control over the release rate is enabled by compartmentalization of the sol-gel solution into droplets of definite size. This can be achieved by emulsification of the sol-gel solution by mixing it with a solution composed of a surfactant and a non-polar solvent (Figure 2.13). When an active molecule is located in the aqueous droplet of a W/O emulsion, encapsulation occurs as the silicon precursors polymerize to build an oxide cage around the active species. By changing the solvent-surfactant combination, the particle size can be varied from 10 nm to 100 pm as the size of the particles is controlled by the size of the emulsion droplet, which acts as a nano-reactor for the sol-gel reaction (Figure 2.13). 

Recently, two new approaches for the preparation of metallodendritic catalysts were described. The first one involves the use of PAMAM dendrimers [11] as both template and stabilizer of metal ions. The cavities of these dendrimers can serve as host type nano-reactors for metal ion guests. This strategy is referred to as reactive encapsulation . The concept was first elegantly demonstrated by... 

New Challenges for Emulsions Biosensors, Nano-reactors, and Templates... 

Pillai V, Kumar P, Hou M J, Ayyub P, Shah DO (1995) Preparation of Nanoparticles of Silver-Halides, Superconductors and Magnetic-Materials Using Water-in-Oil Microemulsions as Nano-Reactors. Adv Colloid Interface Sci 55 241-269... 

In parallel to the emerging interest for asymmetric organocatalysis seen in recent years, the potential development of supramolecular chirality for the construction of asymmetric self-assembling organocatalytic systems is evident. Moreover, the control over the entire space that surrounds a guest allows in theory fine construction of chiral nano-reactors with the ultimate goal of mimicking nature s efficiency and the selectivity observed in enzymes. 

Secondly, the geometric closure of nanoscopic space, either by endo-skeletal or exo-skeletal constructions, creates new surfaces and enclosures upon and where in reactions may be examined. Turro, Barton and Tomalia [40] refer to these domains, whether evolving from micelles, dendrimers or DNA, as nano-reactors". Cram has described such contained space in his carcerands as new phases of matter [41], Miller et al. [42] have used related linear nanostructures as molecular rulers which are observable as single molecular species by transmission electron miecroscope. On the other hand, Amit et al. [16] have shown that important biological events, such as the formation of antigen-antibody complexes involve nanoscopic areas of 600-1000 A2 (6-10 nm2). 

The giant wheel molyhdenum-oxide based anions can be considered as objects which show a variety of nanoscale structural functionalities ( nanostructured landscape ) not only allowing reactions at a variety of well-defined centres/groups but also offering the option of acting as potential nano-reactors or -containers. Some relevant reactions are ... 

Ordered mesoporous materials, due to their periodic and size-controllable pore channels and high surface areas, have been regarded as a nano-reactor to construct novel ordered and well dispersed nanostructured composites with controlled size and size distribution.[303] A number of studies have reported on the encapsulation of guest materials, such as metal oxides,[304] semiconductors, metal sulfides,[305] carbon, metals,[306] and polymers into mesoporous silica hosts. 

Centi, G. and Perathoner, S. Nano-reactor engineering of catalytic surfaces. Invited lecture at 14fh ICC (Seoul, Korea,... 

In the nanowater pools (called nano reactors), nanosized metals and metallic salts can be conveniently synthesised. In the case of synthesis of metals, metal ions from their salts are reduced by different agents like sodium borohydride, ascorbic acid etc. Metallic salts are generally prepared by exchange reactions. The addition or mixing can be done in two ways. 

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