Transmission Electron Microscopy (TEM), X-ray Absorption Near Edge Spectroscopy (XANES), Energy-Loss (EELS), Small-Angle Scattering (SAXS), and SQUID magnetic studies were performed in a batch of horse spleen ferritins from which iron had been gradually removed, yielding samples containing 2200, 1200, 500, 200 atoms. Taken together, findings obtained demonstrate that the ferritin core consists polyphasic structure (ferrihydrite, magnetite, hematite) proportion phases is modified by removal....

A new approach for the preparation of carbohydrate-coated magnetic nanoparticles is reported. In a first step, we show that pH-driven assembly-disassembly natural process occurs in apoferritin protein effective encapsulation maghemite different sizes: 4 and 6 nm. second demonstrate presence functional amine groups outer shell allows functionalization with two carbohydrates, N-acetyl-d-glucosamine d-mannose. High-resolution electron microscopy (HREM), high angle annular dark field scanning...

Copper and CuFe Prussian Blue nanoparticles have been prepared by using a CuII-loaded apoferritin as chemically spatially confined environment for their construction.

Ni and Co nanoparticles (average diameters 3 3.5 nm) have been prepared within the apoferritin cavity. The protein shell prevents bulk aggregation of metal particles, rendering them water soluble. X-Ray diffraction, transmission electronic microscopy magnetization measurements used for characterizing nanoparticles. magnetic study both confirmed expected superparamagnetic behavior.

An electron microscopy study, in combination with modeling and image simulation, of four different reconstituted ferritin samples: recombinant human H L homopolymers, heteropolymers native L-subunit-rich horse spleen H-subunit-rich heart ferritins, points out the existence a correlation between iron core shape protein shell.

The efficiency of maghemite nanoparticles for the treatment anemia was sensibly higher when were incorporated onto probiotic bacterium Lactobacillus fermentum (MNP-bacteria) than administrated as uncoated (MNP). Plasma iron and hemoglobin, intestine expression divalent metal transporter 1 (DMT1) duodenal Cytochrome b (DcytB), well hepatic hormone hepcidin fully restored to healthy levels after administration MNP-bacteria but not MNP. A magnetic study on biodistribution biodegradation showed...

The presence of neuritic plaques and amyloid fibrils arising from the misfolding certain proteins is principal molecular indicator neurodegenerative diseases such as Alzheimer's Parkinson's disease. Methodologies for studying early stages aggregation are rapidly to provide a better understanding mechanism fibrillization cytotoxicity identify potential targets diagnosis therapy. method presented here involves simultaneous use two different fluorophores, quinolimide derivative Nile Blue A....

Three novel cyanide-bridged heterobimetallic coordination polymers have been synthesized by hydrothermal routes, in superheated water solutions, using K3[Co(CN)6], NiCl2.6H2O, and alpha-diimine ligands: [Ni(CN)4Co(phen)] (1; phen = 1,10-phenanthroline), [Ni(CN)4Co(2,2'-bipy)] (2; 2,2'-bipy 2,2'-bipyiridine), [Ni(CN)4Co(2,2'-bipy)2] (3). The isostructural compounds 1 2 contain a two-dimensional network with Co(II) centers octahedrally coordinated one chelating ligand four cyanide groups of...

We have prepared water-soluble gadolinium oxide nanoparticles that show potential as MRI contrast agents. The particles were built into the apoferritin cavity and an average size of 5 nm. After seven days a loss 5% Gd was detected compared with as-prepared samples; after remained constant stabilized inside apoferritin, indicating capsid acts store, avoiding metal delivery consequent toxicity. NMR longitudinal transverse relaxivities resulted about 10 70 times higher than ones clinically...

Biogenic magnetite is a fascinating example of how nature can generate functional magnetic nanostructures. Inspired by the bacteria, an attempt made to mimic their properties, rather than structures, create living magnets at room temperature. The non‐magnetic probiotic bacteria Lactobacillus fermentum and Bifidobacteria breve are used as bioplatforms densely arrange superparamagnetic nanoparticles on external surfaces, thus obtaining artificial bacteria. Magnetic be produced using maghemite...

Abstract Ag nanoparticles of two different sizes (1 and 4 nm) were prepared within an apoferritin cavity by using + ‐loaded as a nanoconfined environment for their construction. The initial amount ions injected in the dictates size final particles. protein shell prevents bulk aggregation metal particles, which renders them water soluble extremely stable.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

A strong focus on Superparamagnetic Iron Oxide Nanoparticles (SPIOs) has been appreciated recently especially for their use in Magnetic Resonance Imaging (MRI). However, some questions are being raised over these particles due to long-term toxicity related the production of toxic free iron during biodegradation. Here we show by Electron Microscopy how SPIOs (P904) (Guerbet, Paris) degraded after they taken up macrophages, so that from SPIO core is progressively incorporated into iron-storing...

New long-circulating maghemite nanoparticles of 4 and 6 nm, coated with an apoferritin protein capsid, exhibit useful properties to act as magnetic resonance imaging (MRI) contrast agents. A full in vivo study the so-called apomaghemites reveals that their long-term MRI are better than those a standard superparamagnetic iron oxide (SPIO) widely used biomedical applications. The biodistribution SPIO was investigated by mice at two different concentrations, 2.5 mg Fe·kg(-1), over 60 days....

Probiotic bacteria were used as carriers of metallic nanoparticles to develop innovative oral agents for hyperthermia cancer therapy. Two synthetic strategies produce the different therapeutic agents. First, probiotic bacterium Lactobacillus fermentum was simultaneously loaded with magnetic (MNPs) and gold (AuNPs) morphologies AuNP + MNP-bacteria systems both types arranged in same layer bacterial exopolysaccharides (EPS). In second approach, first form AuNP-bacteria subsequently MNP-EPS...

Other| December 01, 1997 Epitaxial overgrowth of goethite on hematite synthesized in phosphate media; a scanning force and transmission electron microscopy study Vidal Barron; Barron Universidad de Cordoba, Departamento Ciencias y Recursos Agricolas Forestales, Spain Search for other works by this author on: GSW Google Scholar Natividad Galvez; Galvez Michael F. Hochella; Hochella Jose Torrent American Mineralogist (1997) 82 (11-12): 1091–1100. https://doi.org/10.2138/am-1997-11-1206 Article...

It has been traditionally considered that catechols release iron from ferritin by reduction to iron(II), which diffuses through the channels into intracellular milieu where it participates in Fenton reaction, producing highly toxic hydroxyl radicals. However, present work we have proved mechanism of catechol does not take place iron(II) but direct iron(III) chelation and therefore without production. A possible extension these findings other is discussed on basis stability with respect...

Lactobacillus fermentum, a bacterium of human microbiota, acts as an electron donor for the electrochromic [P2Mo(VI)18O62](6-). Since reductive capacity L. fermentum correlates with its metabolic activity, reaction [P2Mo(VI)18O62](6-) affords means evaluating activity. Following this logic, we have concluded that vancomycin severely affects activity whereas omeprazole does not.

Ferritin, a soluble and highly robust protein with subunits packed into well-defined helices, is key component of the iron regulatory system in brain thus widely recognized as crucial for metabolism, but may also bear possible implications some neurodegenerative disorders. Here, we present evidence how human recombinant apoferritin can convert an unusual structure from its folded native state; that is, amyloid fibrils analogue to those found pathological disorders such Alzheimer's...