Nanospheres transport

Since the uptake of particles in nasal epithelial tissue is known to be mostly mediated by M cells, nasal administration has been investigated as a noninva-sive delivery of vaccines [37], However, since the uptake of naked DNA by endocytocis is limited, use of either nanoparticles as mucosal delivery systems [37] or hypotonic shock [38] is reported for the efficient transfection of gene and vaccine into the nasal epithelium. It was also reported that polypeptides and polypeptide-coated nanospheres (diameter about 500 nm) are transported through endocytic process in rat M cells [39],... 

Transport of carboxylated polystyrene nanospheres (20 nm) across the BBB was studied in vivo following cerebral ischemia and reperfusion [100], A microdialysis probe was... 

As of today, there are no commercially available pharmaceutical products of this technology. The pharmaceutical industry however, is involved in developing nanoparticle-based delivery systems. Use of nanospheres to modify the blood-brain barrier (BBB)—limiting characteristics of the drug enables targeted brain delivery via BBB transporters and provides a sustained release in brain tissue and vaccine delivery systems to deliver therapeutic protein antigens into the potent immune cells are under investigation.103... 

Sanders NN, De Smedt SC, Van Romaey E, Simoens P, De Baets F, Demeester J. Cystic fibrosis sputum a barrier to the transport of nanospheres. Am J Respir Crit Care Med 2000, 162, 1905-1911. 

Fig. 26 Differences in the chlorobenzene (a) and toluene (b) based MDMO-PPV PCBM blend film morphologies are shown schematically. In a both the polymer nanospheres and the fullerene phase offer percolated pathways for the transport of holes and electrons, respectively. In b electrons and holes suffer recombination, as the percolation is not sufficient. (Reprinted from [61], 2005, with permission from Elsevier)...

In the MCNS, the microporous nanospheres are interlinked to form a three-dimensional mesoporous network. Their exceptional performance could be also related with the presence of mesopores which provide a rapid mass transport of ions within the electrode, facilitating the charging and discharging of the double layer. This effect has been already consider when studying activated carbons, which surface capacitance was found to increase with the mesopore content The optimal proportion of mesopores for using activated carbons in EDLCs was found to be between 20 and 50% [57]. 

In polyalkylcyanoacrylate nanoparticles, CyDs are able to slightly decrease the toxic effect induced by polymer degradation on Caco-2 cells [42]. However, saquinavir-loaded CyD nanospheres are not able to promote the transport of this drug through Caco-2 cell monolayers [104]. In contrast, HP-j8-CyD is useful in metoclopramide-loaded nanopartides, where it enhances the absorption of meto-clopramide by a factor of 2 after subcutaneous administration in rat [43]. 

Nanospheres for oral delivery Encapsulating the bioactive molecules prevents enzymatic degradation of drug which makes it an apt vehicle for oral delivery. Nanospheres for drug delivery in the brain Capability of targeting specific receptor-mediated transport system in the blood—brain barrier (BBB) makes nanospheres an ideal choice for drug delivery in the brain. For example, Polysorbate 80/LDL is capable of delivery to the brain. 

Hole-transport layer, 8-42 Hollow nanospheres, 8-53, 8-59 Holmes, 9-18 Holstein theory, 2-13 HOMO, 19-4, 19-20, 19-25, 19-29 HOMO-LUMO gap, 9-14... 

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