A selective spectrophotometric method has been developed for the determination of cobalt after extraction of its 2-methoxyethyl xanthate complex into molten naphthalene. Cobalt reacts with this xanthate in the ratio of 1 : 2 (metal : ligand ratio) in a pH range of 3.5-9.2 and over an acid range of 2.5-7.0 M. It absorbs strongly at 355 nm. Beer's law is obeyed over the concentration range of 2.5...

Dendrite-like cobalt selenide nanostructures were synthesized from cobalt and selenium powder precursors by a solvothermal method in anhydrous ethylenediamine. The as-prepared nanocrystalline cobalt selenide was found to possess peroxidase-like activity that could catalyze the reaction of peroxidase substrates in the presence of H2O2. A spectrophotometric method for uric acid (UA) determination...

iron, cobalt and copper are metals, which appear together in many real samples, both natural and artificial. recently a classical univariate micellar colorimetric method has been developed for determination of these metal ions. the organized molecular assemblies such as micelles are used in spectroscopic measurements due to their possible effects on the systems of interest. the ability of micel...

Highly rapid and selective vortex-assisted liquid-liquid microextraction based on solidification of organic drop has been used for determination of cobalt ion. 2-Nitroso-1-naphthol (2N1N) was used as a selective complexing agent to form stable cobalt-2N1N complex which can be extracted with 1-undecanol at a short time by the assistance of vortex agitator system followed by its determination usi...

Optimized and validated spectrophotometric methods have been proposed for the determination of iron and cobalt individually and simultaneously. 2-hydroxy-1-naphthaldehyde-p-hydroxybenzoichydrazone (HNAHBH) reacts with iron(II) and cobalt(II) to form reddish-brown and yellow-coloured [Fe(II)-HNAHBH] and [Co(II)-HNAHBH] complexes, respectively. The maximum absorbance of these complexes was found ...

Cobalt (II) reacts with 5-methylfuran-2-carbaxaldehyde thiosemicarbazone (5-MFAT) and forms a light yellow colored complex, which was extracted into isobutanol from sodium acetate and acetic acid buffer at pH 6.0. The absorbance value of the Co (II)–5-MFAT complex was measured at different intervals of time at 360 nm, to ascertain the time stability of the complex. The extraction of the complex...

The present article reports on the application of modified organo nanoclay as a green, easily prepared and stable solid sorbent for the preconcentration of trace cobalt ion in aqueous solution. The organo nanoclay was modified by adsorption of 5-(4-dimethyl amino-benzylidene) rhodanin reagent onto it. The sorption of Co2+ ions was quantitative in the pH range of 7.0 to 8.5, whereas quantitative...

A rapid and sensitive method has been proposed for the determination of chromium and cobalt in seafood samples by flame atomic absorption spectrometry combined with a dynamic ultrasound-assisted acid extraction and an on-line minicolumn preconcentration. The use of diluted nitric acid as extractant in a continuous mode at a flow rate of 3.5 mL min(-1) and room temperature was sufficient for qua...