Recent advances in label free DNA hybridization sensors employing electrochemical impedance spectroscopy (EIS) as a detection tool are reviewed. These sensors are based on the modulation of the blocking ability of an electrode modified with a probe DNA by an analyte, i.e., target DNA. The probe DNA is immobilized on a self-assembled monolayer, a conducting polymer film, or a layer of nanostruct...

A promising electrochemical sensor was fabricated by the self-assembling of Pt nanoparticles (nano-Pts) on a chitosan (CS) modified glassy carbon electrode (GCE). A field-emission scanning electron microscope (FE-SEM), transmission electron microscopy (TEM) and electrochemical techniques were used for characterization of these composites. It has been found that nano-Pts are inserted into the CS...

high priority at military facilities where site management costs can be very high. A novel approach to control plume migration utilizes electrolytic permeable reactive barriers to degrade these chemical in situ. This research focuses on characterizing the relationship between electrode surface morphology and composition with the rate of electrochemical reduction for mixtures of cyclic nitramine...

An amperometric sensor was constructed, by using humic acids to immobilize Fe3+ ions on a carbon paste electrode (CPE-HA-Fe), and used for ascorbic acid (H2A) determination. The cyclic voltammogram of the electrode showed electrochemical response due to the Fe3+/Fe2+ couple at E1/2=+0.78 V vs SCE, using 0.5 mol L-1 KCl and 0.2 mol L-1 acetate/0.020 mol L-1 phosphate buffer, at pH = 5.4, as supp...

Covalent grafting of chromotropic acid (CA) moiety to a glassy carbon electrode was performed by electrochemical reduction of the corresponding diazonium cation generated in situ. Grafted electrodes were subjected to the electrochemical detection of multivalent cations using Fe(CN)(6)(3-/4-) as an electrochemical probe molecule. In the absence of metal cations, redox reaction of the anionic p...

An ion-channel sensor was demonstrated by immobilizing ETH 1001, an ionophore for ion-selective electrodes, on a gold electrode surface. The approach for preparing the sensor was to incorporate the ionophore into a mixed self-assembled monolayer of 10-mercaptodecanesulfonate and 11-hydroxy-1-undecanethiol formed on the surface. The voltammetric responses for the thus prepared sensor to the prim...

We report on the fabrication and characterization of an 8 × 8 multichannel Boron Doped Diamond (BDD) ultramicro-electrode array (UMEA). The device combines both the assets of microelectrodes, resulting from conditions in mass transport from the bulk solution toward the electrode, and of BDD's remarkable intrinsic electrochemical properties. The UMEAs were fabricated using an original approach r...

Determination of the stability constants of dissolved iron(III) glycine system in water solution (I = 0.6 mol L in NaClO4, pH = 7.3 at 25±1 oC) using differential pulse cathodic voltammetry (DPCV) and cyclic voltammetry (CV) was performed out on a static mercury drop electrode (SMDE). By choosing voltammetry as analytical tool, measurements with lower iron(III) concentrations (10 mol L), at the...

OBJECTIVE: This multicenter study describes the effects of perimodiolar electrode position on 50 adult patients (31 with an implanted Nucleus 24 Contour perimodiolar hugging electrode array [Cochlear Limited, Lane Cove, NSW, Australia] and 19 with an implanted straight electrode array) with a severe-to-profound sensorineural hearing loss. MATERIALS AND METHODS: In all patients, intraoperative i...

Introduction: The response variability between subjects, which is one of the fundamental challenges facing transcranial direct current stimulation (tDCS), can be investigated by understanding how the current is distributed through the brain. This understanding can be obtained by means of computational methods utilizing finite element (FE) models. Materials and Methods: In this study, the effect...