in this work, the results concerning to the mean activity coefficient measurements for nacl in the (glycerol + water) system using the potentiometric method are reported. the potentiometric measurements were performed on the galvanic cells without liquid junction of the type: ag|agcl|nacl (m), glycerol (wt%), h2o (1 - wt)%|na-ise, in various mixed solvent systems containing 0, 5, 10, 20 and 30 ...

the acidity constants of some amino acids (am) were determined by potentiometric ph titration. the stability constants of the 1:1 complexes formed between m2+: ca2+, mg2+, mn2+, co2+, ni2+, cu2+ or zn2+ and am2-, were determined by potentiometric ph titration in aqueous solution (i = 0.1 m, nano3, 25°c). the order of the stability constants was reported. it is shown that the stability of the bi...

The chemical methods for estimation of vitamin E, recommended in the literature, are all based on the oxidation ofa hydroquinone nucleus which is present in all modifications of tocopherol. This nucleus can either be oxidized in such a way as to give a coloured product, or its reducing power may be measured and hence the quantity of tocopherol calculated. The latter principle is employed in the...

Unraveling the biology, pharmacology, and toxicology of NO depends on accurate NO assays, two of the more common being the oxyHb (oxyhemoglobin) assay and potentiometric detection using a Clark-type NO-selective electrode. Comparison of the specificity and sensitivity of the oxyHb and potentiometric methods was carried out using a broad series of nitrovasodilators, including organic nitrates, n...

Potentiometric sensors are attractive tools for the fabrication of various electronic tongues that can be used in wide area of applications, ranging from foodstuff recognition to environmental monitoring and medical diagnostics. Their main advantages are the ability to modify their selectivity (including cross-sensitivity effects) and the possibility of miniaturization using appropriate constru...

The effects of nitrogenous synergists on the potentiometric responses to divalent transition metal ions were investigated concerning polymeric liquid membranes containing thenoyltrifluoroacetone (Htta) as an ionophore. The tested synergists were pyridine (py) and 4,4'-dioctyl-2,2'-bipyridyl (C8bpy). The potentiometric responses to metal ions, such as Cd2+, Co2+, Ni2+ and Zn2+, were induced by a...

Bacillus pyocyaneus produces, according to the conditions, different varieties of pigment of which pyoeyanine is best known and easily isolated because of its solubility in chloroform. This pigment is indigo blue at alkaline reaction, wine-red at acid reaction, and is reducible to a leuco compound by various reductants or in the absence of air by the living bacillus itself, and the leucodye is ...

For the first time, an MIP potentiometric sensor based covalent recognition for determination of protonated dopamine is described.