The electrochemistry of 3-alkoxy- and 3-hydroxy-1-[omega-(dialkylamino)alkyl]-5-nitroindazole derivatives were characterized using cyclic voltammetry in DMSO. The nitro reduction process was studied and this was affected by the acid moieties present in these compounds. A nitro anion self-protonation process was observed. This phenomenon was studied by cyclic voltammetry in presence of increasin...

Voltammetric detection of metals in natural waters suffers from interference by dissolved oxygen. We describe here a deoxygenation method suitable for ̄ow analysis with detection by cathodic stripping voltammetry (FIA-CSV). The apparatus is based on the permeation of oxygen through semi-permeable tubing (silicone, Pore ̄on and others) into an oxygen-free chamber. Two methods of oxygen removal ar...

A mercury-sensitive chemically modified graphite paste electrode was constructed by incorporating modified silica gel into a conventional graphite paste electrode. The functional group attached to the (3-chloropropyl) silica gel surface was 2-mercaptoimidazole, giving a new product denoted by 3-(2-thioimidazolyl)propyl silica gel, which is able to complex mercury ions. Mercury was chemically ad...

In the oxygen-rich layer of the Black Sea, above the permanent halocline, the Fe and nitrate concentrations are low where fluorescence is relatively high, indicating uptake by phytoplankton. In this study we used ligand exchange adsorptive cathodic stripping voltammetry (CLE-aCSV), using 2-(2-Thiazolylazo)-p-cresol (TAC) as measuring ligand, to investigate the role of Fe-binding dissolved organ...

ABSTRACT In this paper, the square-wave adsorptive stripping voltammetric (SWAdSV) determination of the veterinary drug closantel using a renewable silver amalgam film electrode (Hg(Ag)FE) is presented. As observed in SWAdSV, closantel provided one well-shaped reduction peak suitable for analytical purposes at potential ca. -1.4 V in the Britton-Robinson (B-R) buffer at pH 7.0. At optimal condi...

Hydrothermal vent fluids are highly enriched in iron (Fe) compared to ambient seawater, and organic ligands may play a role in facilitating the transport of some hydrothermal Fe into the open ocean. This is important since Fe is a limiting micronutrient for primary production in large parts of the world’s surface ocean. We have investigated the concentration and speciation of Fe in several vent...

Carbonic anhydrase (CA) is inactive unless associated with zinc, with possible substitution by cobalt. In this work, the complexation of zinc by CA was determined in sea-water using cathodic stripping voltammetry (CSV) with ligand competition. The zinc was found to be released from the CA over a period of 3 h when equilibrated with a competing complexing ligand and the complex was re-formed wit...

Total dissolved Zn and Zn speciation were investigated by cathodic stripping voltammetry (CSV) in the northeastern Indian Ocean and the Andaman Sea. Vertical distributions of total dissolved Zn concentration (CZn) in the northeastern Indian Ocean and the Andaman Sea reflect that the deep water from the Andaman Sea was rapidly replaced by incoming waters from the northeastern Indian Ocean across...

Trace minerals play an essential role in methane production via anaerobic digestion (AD). It is important to monitor Ni(II) and Co(II) concentrations the Ni/Co concentration ratio for rapid diagnosis of ecological status or activity methanogens AD. Electrochemical detection was investigated by coating Bi-chitosan nanocomposite on a glassy carbon electrode (GCE) electrodeposition technique. A sq...