Search results for "Superparamagnetism"
showing 4 items of 54 documents
Multifunctional polymer-derivatized γ-Fe2O3 nanocrystals as a methodology for the biomagnetic separation of recombinant His-tagged proteins
2008
Abstract Multifunctional polymer-derivatized superparamagnetic iron oxide (γ-Fe2O3) nanoparticles were prepared for biomagnetic separation of histidine-tagged recombinant proteins building up a faster and efficient method for protein separation by making use of their intrinsic magnetic properties. Using polymer bound γ-Fe2O3 nanocrystals, a 6× histidine-tagged recombinant protein (silicatein) with a molecular weight of 24 kDa has been isolated and purified. The supermagnetic iron oxide nanocrystals were characterized by transmission electron microscopy (TEM), high-resolution TEM (HRTEM), SQUID and Mossbauer and the polymer functionalization of the γ-Fe2O3 nanocrystals was monitored by UV–vi…
Langmuir–Blodgett films based on inorganic molecular complexes with magnetic or optical properties
2005
Langmuir and Langmuir–Blodgett (LB) films of a great variety of molecular metal complexes with interesting magnetic or optical properties have been prepared in the last few years. Some of the results obtained by our group and others are summarized in this article. (i) LB films of polyoxometalates (POM) were first prepared taking advantage of the adsorption properties of these cluster anions along a positively charged monolayer of an organic surfactant spread in water. A correct choice of the POM allowed the preparation of LB films with magnetic, electrochromic, or luminescent properties. Besides this semiamphiphilic method, two new methods to prepare LB films of POMs have been developed by …
Metal Oxide/Polymer Hybrid Nanoparticles with Versatile Functionality Prepared by Controlled Surface Crystallization
2012
Metal oxide/polymer hybrids are prepared from polystyrene nanoparticles functionalized at the surface with phosphonate and phosphate groups. The polymer particles are synthesized with specifically designed surface-active monomers (surfmers) and used as nucleation surfaces for the controlled in situ crystallization of cerium, iron, and zinc oxide nanocrystals. The formation of the metal oxide is driven by the addition of a base to suspensions of the polymer particles containing the corresponding precursor. The crystal formation at the particle surface is studied for the different hybrid systems by X-ray diffraction and transmission electron microscopy (TEM). The potential catalytic activity …
Evaluation of Superparamagnetic Silica Nanoparticles for Extraction of Triazines in Magnetic in-Tube Solid Phase Microextraction Coupled to Capillary…
2014
The use of magnetic nanomaterials for analytical applications has increased in the recent years. In particular, magnetic nanomaterials have shown great potential as adsorbent phase in several extraction procedures due to the significant advantages over the conventional methods. In the present work, the influence of magnetic forces over the extraction efficiency of triazines using superparamagnetic silica nanoparticles (NPs) in magnetic in tube solid phase microextraction (Magnetic-IT-SPME) coupled to CapLC has been evaluated. Atrazine, terbutylazine and simazine has been selected as target analytes. The superparamagnetic silica nanomaterial (SiO2-Fe3O4) deposited onto the surface of a capil…