Fluorescent nanoparticles have a variety of biomedical applications as diagnostics and traceable drug delivery agents. Highly fluorescent porous silica nanoparticles were synthesized in a water/oil phase by a microemulsion method. What is unique about the resulting porous silica nanoparticles is the combination of a single-step, efficient synthesis and the high stability of its fluorescence emi...

in this study, sio2 nanoparticles were successfully synthesized via sol-gel precipitation method and the effects of different parameters such as temperature, ethanol, ammonia and tetraethylorthosilicate (teos) contents based on water were investigated in a systematic way applying taguchi experimental design method. it was found that, among all the investigated parameters, ethanol as a co-solven...

The surface aggregate structure of dimethyldodecylamine-N-oxide (C(12)DAO) in three silica dispersions of different particle sizes (16-42 nm) was studied by small-angle neutron scattering (SANS) in a H(2)O/D(2)O solvent mixture matching the silica. At the experimental conditions (pH 9), the surfactant exists in its nonionic form, and the structure of the adsorbed layer is not affected by added ...

Occupational exposure to crystalline silica is a well-established occupational hazard. Once in the lung, crystalline silica particles can result in the activation of alveolar macrophages potentially leading to silicosis, a fibrotic lung disease. Because the activation of alveolar macrophages is the beginning step in a complicated inflammatory cascade, it is necessary to define the particle char...

The goal of this research is to determine the feasibility of loading rifampin into mesoporous silica nanoparticles. Rifampin was selected as a model lipophilic molecule since it is a well-documented and much used anti tuberculosis drug. The mesoporous silica nanoparticles were prepared by using Tetraethyl ortho silicate and cetyltrimethyl ammonium bromide (as surfactant); The prepared nanoparti...

Twenty nine samples of silica sinter, ranging in age from modern to Miocene, record temporal changes in both mineralogy and texture. When ®rst deposited, sinters consist largely of noncrystalline spheres (<1±8 lm diameter) of opal-A exhibiting varying degrees of closepacking. Particle densities range from 1.5 to 2.1 g cm, total water 4±10 wt%, and porosities 35±60%. Changes over 10,000 years fo...

We developed a straightforward method to form non-close-packed highly ordered fcc direct and inverse opal silica photonic crystals. We utilize an electrostatically self assembled crystalline colloidal array (CCA) template formed by monodisperse, highly charged polystyrene particles. We then polymerize a hydrogel around the CCA (PCCA) and condense silica to form a highly ordered silica impregnat...

Pickering emulsions are emulsions whose drops are stabilized against coalescence by particles adsorbed at their interface. Recent research on oil/water/particle systems shows that particles can sometimes adsorb at two oil/ water interfaces. Such “bridging particles” can glue together drops of oil in water or vice versa. We hypothesize that the same effect should apply in immiscible polymer blen...

Magnetic properties of particles are generally determined from randomly oriented ensembles and the influence of the particle orientation on the magnetic response is neglected. Here, we report on the magnetic characterization of anisotropic spindle-type hematite particles. The easy axis of magnetization is within the basal plane of hematite, which is oriented perpendicular to the spindle axis. T...