@misc{RoznyatovskayaLaurinavichyuteTsirlinaetal., author = {Roznyatovskaya, Nataliya V. and Laurinavichyute, Veronika K. and Tsirlina, Galina A. and Mirsky, Vladimir M.}, title = {Electrochemistry and catalytic behavior of immobilized binuclear complexes of copper(II) and nickel(II) with Robson type ligand}, series = {Journal of Solid State Electrochemistry}, volume = {11}, journal = {Journal of Solid State Electrochemistry}, number = {7}, issn = {1432-8488}, doi = {10.1007/s10008-006-0235-7}, pages = {981 -- 992}, abstract = {Various systems containing immobilized binuclear copper(II) and nickel(II) complexes with Robson type ligand ([M2L]Cl2) are studied and compared in relation to catalysis of hydrogen peroxide reduction. Molecular complexes adsorbed on mercury and gold, crystalline complexes immobilized in the carbon paste electrode, and complex species entrapped into polyphenol-modified gold electrodes are considered. Electrocatalysis is assumed to result from the formation of H2O2-[M2L]Cl2 adduct, not from mediating redox transformations. Possible geometry of the formed reaction layers supporting adduct formation is discussed.}, language = {en} } @misc{LaurinavichyuteNizamovMirsky, author = {Laurinavichyute, Veronika K. and Nizamov, Shavkat and Mirsky, Vladimir M.}, title = {The Role of Anion Adsorption in the Effect of Electrode Potential on Surface Plasmon Resonance Response}, series = {ChemPhysChem : a European journal of physical chemistry and chemical physics}, volume = {18}, journal = {ChemPhysChem : a European journal of physical chemistry and chemical physics}, number = {12}, issn = {1439-7641}, doi = {10.1002/cphc.201601288}, pages = {1552 -- 1560}, abstract = {Surface plasmon resonance, being widely used in bioanalytics and biotechnology, is influenced by the electrical potential of the resonant gold layer. To evaluate the mechanism of this effect, we have studied it in solutions of various inorganic electrolytes. The magnitude of the effect decreases according to the series: KBr>KCl>KF>NaClO4. The data were treated by using different models of the interface. A quantitative description was obtained for the model, which takes into account the local dielectric function of gold being affected by the free electron charge, diffuse ionic layer near the gold/water interface, and specific adsorption of halides to the gold surface with partial charge transfer. Taking into account that most biological experiments are performed in chloride-containing solutions, detailed analysis of the model at these conditions was performed. The results indicate that the chloride adsorption is the main mechanism for the influence of potential on the surface plasmon resonance. The dependencies of surface concentration and residual charge of chloride on the applied potential were determined.}, language = {en} } @misc{LaurinavichyuteNizamovMirsky, author = {Laurinavichyute, Veronika K. and Nizamov, Shavkat and Mirsky, Vladimir M.}, title = {Real time tracking of the early stage of electrochemical nucleation}, series = {Electrochimica Acta}, volume = {382}, journal = {Electrochimica Acta}, issn = {0013-4686}, doi = {10.1016/j.electacta.2021.138278}, pages = {8}, abstract = {An analysis of early stage of electrochemical nucleation is crucial in order to understand the mechanism of this process and for electrochemical synthesis of new materials. We show here an application of the wide field surface plasmon microscopy (WF-SPRM) for this purpose. It allows us in-situ monitoring of the growth of nuclei in the range from ~20 till over 1000 nm. The system registers the moment and the place of the formation of each individual nucleus for the total number of the tracked nuclei up to ~10,000 per 1 mm2. The results demonstrate that the integral information obtained from electrochemical measurements can be extracted quantitatively from optical measurements while optical data provide also information on the size of each individual nucleus, individual nucleation time, localization and growth kinetics, and allows one to distinguish the rate limiting stage for each individual nucleus. In this work WF-SPRM was applied for investigation of electrochemical deposition of copper on gold, but this technique can be extended easily to other materials or other nucleation types.}, language = {en} } @misc{KolosovaEfremenkoLaurinavichyuteetal., author = {Kolosova, Olga S. and Efremenko, Yulia and Laurinavichyute, Veronika K. and Nizamov, Shavkat and Petrushenko, Serhii I. and Mirsky, Vladimir M.}, title = {Poly-3-thienylboronic Acid Nanoparticles: Synthesis, Characterization, and Interaction with Saccharides Studied at the Level of Individual Nanoparticles}, series = {ACS Applied Nano Materials}, volume = {7}, journal = {ACS Applied Nano Materials}, number = {10}, publisher = {American Chemical Society}, issn = {2574-0970}, doi = {10.1021/acsanm.4c00216}, pages = {11120 -- 11135}, abstract = {Polythiophenboronic acid (PThBA) combines an affinity for saccharides with the unique properties of conducting polymers. This polymer was synthesized by enzymatic catalyzed oxidative polymerization, characterized by UV-vis spectroscopy in solvents of different polarity and by 1H NMR. A suspension of PThBA nanoparticles (PThBA NPs) was prepared by injecting a methanol solution of PThBA into an aqueous electrolyte. PThBA NPs were characterized by scanning electron microscopy. Nanoparticle tracking analysis and dynamic light scattering were used to study the concentration of the particles and the particle size distribution. The effect of pH on these properties was analyzed and an increase in nanoparticle size was observed at alkaline pH. This effect was explained by electrostatic swelling of the nanoparticles. Measurements of ζ-potentials in the wide pH range showed the presence of acidic groups with a pKa of 8.6; the value of the surface charge at the conditions of maximal deprotonation of these groups was estimated to be ∼70 mC/m2. Changes in the optical spectra of PThBA NPs due to variations in pH and additions of organic solvents indicate transformations between twisted and planar conformations of the polymer backbone. The binding of saccharides by PThBA NPs resulted in a decrease in the size and charge of the nanoparticles. Recently developed wide-field surface plasmon resonance microscopy (WF-SPRM) can simultaneously monitor every single nanoparticle among many thousands adsorbed on a surface. It was used for the first time to study chemosensitive nanoparticles. The described above effects of pH change and saccharide binding described above, monitor were confirmed by using integral techniques in monitoring individual nanoparticles, by WF-SPRM. The pH effects were shown to be reversible. An increase in the affinity of PThBA NPs for saccharides at a more alkaline pH was also observed. A fast recovery of polymer binding sites by a pH decrease was demonstrated. The synthesized and characterized PThBA NPs can be further used for various purposes including analytical assays, chemical sensors, or chemosensitive nanotechnological devices.}, subject = {-}, language = {en} }