The importance of the active complexes of 6 - mercaptopurine with Bi(III) with regards to kinetics and electrode mechanism changes in the presence of non-ionic surfactants

Rhodamine 6G-Anionic Surfactant System Modified by Triton X-100 for Fluorescence Determination of Albumin

The influence of sodium hexadecyl sulfate on the nature of the fluorescence spectra of rhodamine 6G in an aqueous solution and a solution of nonionic Triton X-100 was investigated. The change in the nature of the emission spectra is explained by the formation of hydrophobic stoichiometric and sub-stoichiometric reagent-surfactant associates. Stabilization of the colloid-chemical state and reduction of the total turbidity of rhodamine 6G-anionic surfactant associate solutions with the addition of nonionic surfactant as a modifier were registered. The method of modification of the rhodamine 6G-sodium hexadecyl sulfate system with a nonionic surfactant was used in the development of conditions for the fluorescence determination of protein substances in physiological solutions. The concentration conditions for the use of the modified reagent system rhodamine 6G-anionic surfactant-nonionic surfactant for the fluorescence determination of albumin in urine were optimized.

Application of the nanostructured R-AgLAFE electrode to study the electroreduction process of Bi(III) ions in the presence of N-acetylcysteine

Bi(III) ions electroreduction in the presence of N-acetylcysteine (ACYS)at the nanostructured R-AgLAFE electrode has been studied by the voltammetric and impedance measurements. The experimental data indicates the multistage character of the electrode process and the catalytic influence of N-acetylcysteine on the Bi(III) ions electroreduction rate. It was found that this process is controlled by the chemical reaction of the Bi(III)–Hg(SR)2 activecomplexes formation on the electrode surface, which mediates electron transfer. Active complexes are a substrate in the process of electroreduction, and their different structure and properties are the reason for the diverse catalytic activity of N-acetylcysteine.

Influence of mixed 2-thiocytosine–ionic surfactants adsorption layers on kinetics and mechanism of Bi(III) ions electro reduction: use of the nanostructured R-AgLAFE

The nanostructured cyclically refreshable liquid amalgam film silver-based electrode (R-AgLAFE) was applied to study of the Bi(III) electrode process in the presence of 2-thiocytosine and selected ionic surfactants. The application of voltammetrictechniques (SWV, CV, DC), as well as electrochemical impedance spectroscopy (EIS) allowed the determination of the kinetic which in turn, defined the 2-thiocytosine catalytic effect and also their correlation in the presence of surfactants. The presence of mixed 2-thiocytosine-CTAB and 2-thiocytosine-SDS adsorption layers affects the mechanism and kinetics of Bi(III) ions electro-reduction process in chlorate(VII). CTAB and SDS change the dynamics of the catalytic impact of 2-thiocytosine on Bi(III) ions electro reduction. In both cases, the Bi–(RS–Hg) complex plays a key role, as it is the 2-thiocytosine that dominates in the establishment of the adsorption equilibria of the studied mixed adsorption layers.

Electroreduction of Bi(III) ions in the aspect of expanding the “cap-pair” effect: the role of the nanosized active complexes

The paper discusses the electroreduction of Bi(III) ions in the aspect of expanding the “cap-pair” effect.

The “cap-pair” rule is associated with the acceleration of the electrode’s processes by organic substances. The interpretation of the “cap-pair” effect mechanism was expanded to include the effect of supporting electrolyte concentration on the acceleration process and the type of electrochemical active as well as used protonated organic substances. It has also been shown that the phenomena occurring at the electrode/solution interface can influence a change in the dynamics of the electrode’s process according to the “cap-pair” rule.