in this study, magnetic iron oxide nanoparticles (fe3o4) with the size range of 20-30 nm were prepared by the modified controlled chemical co-precipitation method from the solution of ferrous/ferric mixed salt-solution in alkaline medium. in this process polyethylene glycol was used as a surfactant to prevent the solution from agglomeration. the prepared magnetic nanoparticles were characterize...

We developed a new method to measure iron reduction at a distance based on depositing Fe(III) (hydr)oxide within nanoporous glass beads. In this "Fe-bead" system, Shewanella oneidensis reduces at least 86.5% of the iron in the absence of direct contact. Biofilm formation accompanies Fe-bead reduction and is observable both macro- and microscopically. Fe-bead reduction is catalyzed by live cells...

We compare the activity and relevant gold species of nanostructured gold–cerium oxide and gold–iron oxide catalysts for the CO oxidation by dioxygen and water. Well dispersed gold nanoparticles in reduced form provide the active sites for the CO oxidation reaction on both oxide supports. On the other hand, oxidized gold species, strongly bound on the support catalyze the water-gas shift reactio...

zinc and iron nano-oxides (100 ppb) were promoted the hypericin and hyperforin production in hypericum perforatum cell suspension culture. high performance liquid chromatography method was used for detectection and identification of hypericin and hyperforin in h. perfuratum cell suspension cultures elicited with different concentrations of zinc and iron nano-oxide (0, 50, 100 and 150 ppb) after...

Natural products with important therapeutic properties are known to be produced by a variety of soil bacteria, yet the ecological function of these compounds is not well understood. Here we show that phenazines and other redox-active antibiotics can promote microbial mineral reduction. Pseudomonas chlororaphis PCL1391, a root isolate that produces phenazine-1-carboxamide (PCN), is able to reduc...

Mining-impacted sediments of Lake Coeur d'Alene, Idaho, contain more than 10% metals on a dry weight basis, approximately 80% of which is iron. Since iron (hydr)oxides adsorb toxic, ore-associated elements, such as arsenic, iron (hydr)oxide reduction may in part control the mobility and bioavailability of these elements. Geochemical and microbiological data were collected to examine the ecologi...