Fe3O4 nanoparticles: protein-mediated crystalline magnetic superstructures.

The synthesis of magnetic, monodisperse nanoparticles has attracted great interest in nanoelectronics and nanomedicine. Here we report the fabrication of pure magnetite nanoparticles, less than ten nanometers in size, using the cage-shaped protein apoferritin (Fe(3)O(4)-ferritin). Crystallizable proteins were obtained through careful successive separation methods, including a magnetic chromatography that enabled the effective separation of proteins, including a Fe(3)O(4) nanoparticle (7.

A comparison of the cyclic voltammetry of the Sn/Sn(II) couple in the room temperature ionic liquids N-butyl-N-methylpyrrolidinium dicyanamide and N-butyl-N-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide: solvent induced changes of electrode reaction mechanism.

The Sn/Sn(II) couple is studied in the room temperature ionic liquids N-butyl-N-methylpyrrolidinium dicyanamide, [C(4)mpyrr][N(CN)(2)] and N-butyl-N-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide, [C(4)mpyrr][NTf(2)] using cyclic voltammetry. The Sn(II) species is introduced into each of the ionic liquids by dissolving either SnCl(2) or Sn(CF(3)SO(3))(2). The diffusion coefficient of the Sn(II) species produced is found to vary with the ionic liquid, partly reflecting the difference in the viscosity of the two liquids, but also to vary with the Sn(II) salts used, indicating that different Sn(II) species may be present.

Kinetic and thermodynamic parameters of the Li/Li+ couple in the room temperature ionic liquid N-butyl-N-methylpyrrolidinium bis(trifluoromethylsulfonyl) imide in the temperature range 298-318 K: a theoretical and experimental study using Pt and Ni electrodes.

The Li/Li+ couple is investigated in the room temperature ionic liquid N-butyl-N-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide, [C4mpyrr][NTf2], at a range of temperatures varying from 298 to 318 K.Experiments are conducted using both nickel and platinum microelectrodes. On nickel, a single stripping peak is observed for the stripping of bulk lithium that allowed thermodynamic and kinetic parameters to be extracted via computational simulation.

General theory of cathodic and anodic stripping voltammetry at solid electrodes: mathematical modeling and numerical simulations.

Theory is presented to describe the voltammetric signals associated with the stripping phase of stripping voltammetry at solid electrodes. Three mathematical models are considered, and the importance of the hemispherical diffusion associated with electrochemical dissolution of particles in the micrometer range is investigated. Model A considers a "monolayer" system where the coverage at a specific point cannot exceed a maximum value.

Boron-doped diamond microdisc arrays: electrochemical characterisation and their use as a substrate for the production of microelectrode arrays of diverse metals (Ag, Au, Cu)via electrodeposition.

A novel boron-doped diamond (BDD) microelectrode array is characterised with electrochemical and atomic force microscopic techniques. The array consists of 40 micron-diameter sized BDD discs which are separated by 250 microns from their nearest neighbour in a hexagonal arrangement. The conducting discs can be electroplated to produce arrays of copper, silver or gold for analytical purposes in addition to operating as an array of BDD-microelectrodes.

Novel methods for the production of silver microelectrode-arrays: their characterisation by atomic force microscopy and application to the electro-reduction of halothane.

A new method is proposed for the simple preparation of random silver micro and nano-electrode arrays. This employs acoustic streaming directed at a glassy carbon surface to "mechanically" attach particles from a suspension of metal colloidal or other small particles. The particles tend to adhere to the substrate at points of imperfection such as scratches, crevices etc.

Acoustically fabricated random microelectrode assemblies.

We report the insonation of bismuth, silver, copper and tungsten metal particles suspended in octane in the vicinity of a glassy carbon electrode. AFM and voltammetry reveal that metal particles are immobilised onto the electrode substrate. In the case of bismuth, silver and copper, the possible melting of the metal particles due to the high sonochemical conditions cannot unambiguously be ruled out.