Nanospheres diameter

Figure 3.2 Extinction spectra of colloidal water solutions of gold nanospheres and nanorods. Dotted curve nanospheres (diameter 15-25 nm). Solid curve nanorods, low aspect ratio. Dashed curve nanorods, high aspect ratio. Extinction is normalized at about 520 nm. (Reproduced with permission from Royal Society of Chemistry [10]).

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],... 

Figure 16.7 Tunability of the extinction cross-section of gold nanostnictuies. Variation of Cext with (a) nanosphere diameter D (b) nanoshell total radius R2 with fixes R1/R2 = 0.857 (c) nanoshell core/shell ratio R1/R2 at fixed R2 = 70 nm (d) nanorod effective radius r ff = (3V/4II) at fixed aspect ratio R = A/B = 3.9 (e) nanorod aspect ratio R at fixed r ff = 11.43 nm. (Reproduced with permission from P. K. Jain et al., 2006. J. Phys. Chem. B 110 7238-7248. Copyright 2006 American Chemical Society.)...

Therefore, RMs with an initial wo = 20 became unstable as soon as the reaction was initiated, and this resulted in tri-modal nanosphere diameter distributions... 

We start by discussing the effect of nanosphere diameter on the phase behavior of monotethered nanospheres in sdective solvent, wherein tethers are in poor solvent and nanospheres are in good solvent (i.e., tethers tend to a egate, nanospheres do not). This system has solvent conditions opposite to those in... 

We note that large values of Pv tend to favor stmctures with high curvature (i.e, spheres), whereas low values favor lamellar stmctures with flat interfaces, and at sufficiently low values, systems with inverted curvature (i.e., PLH). This demonstrates that small changes to the nanosphere diameter relative to the tether may result in a large change to the phase behavior for these dense systems. 

Nanosphere A spherical particle of submicrometer diameter consisting of a solid monolithic polymer matrix with no discernable core. 

The procedure chosen for the preparation of lipid complexes of AmB was nanoprecipitation. This procedure has been developed in our laboratory for a number of years and can be applied to the formulation of a number of different colloidal systems liposomes, microemulsions, polymeric nanoparticles (nanospheres and nanocapsules), complexes, and pure drug particles (14-16). Briefly, the substances of interest are dissolved in a solvent A and this solution is poured into a nonsolvent B of the substance that is miscible with the solvent A. As the solvent diffuses, the dissolved material is stranded as small particles, typically 100 to 400 nm in diameter. The solvent is usually an alcohol, acetone, or tetrahydrofuran and the nonsolvent A is usually water or aqueous buffer, with or without a hydrophilic surfactant to improve colloid stability after formation. Solvent A can be removed by evaporation under vacuum, which can also be used to concentrate the suspension. The concentration of the substance of interest in the organic solvent and the proportions of the two solvents are the main parameters influencing the final size of the particles. For liposomes, this method is similar to the ethanol injection technique proposed by Batzii and Korn in 1973 (17), which is however limited to 40 mM of lipids in ethanol and 10% of ethanol in final aqueous suspension. 

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