Digitální knihovnaUPCE
 

26 (2020) Scientific papers, Series A

Permanentní URI k tomuto záznamuhttps://hdl.handle.net/10195/76706

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20202

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Autor: search.filters.author.Sýs, Milan

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Nyní se zobrazuje 1 - 2 z 2
  • Náhled
    Článekpeer-reviewedpublishedOtevřený přístup
    Electrochemical behaviour of substances responsible for the vanilla aroma and a study of their structural analogues at the glassy carbon electrode
    (University of Pardubice, 2020) Farag, Amir Shaaban; Švancara, Ivan; Sýs, Milan
    In this article, the electrochemical behaviour of vanillin, ethylvanilin, and of their structural analogues has been studied at the glassy carbon electrode using cyclic voltammetry. Based on experimental observations and information from literature, the respective electrode reaction pathways were proposed according to the ECE mechanisms in all cases, when up to three oxidation products were identified from one reactant. It has been found that the electrode oxidation of vanillin and ethylvanillin occurs in one single step, followed by hydrolysis in ortho-position and/or cleavage of the corresponding alcohol, giving rise to two electrochemically reversible oxidation products.
  • Náhled
    Článekpeer-reviewedpublishedOtevřený přístup
    Comparison of two different approaches for determination of biomimetic activity of selected copper complexes
    (University of Pardubice, 2020) Sýs, Milan; Novák, Miroslav; Mikysek, Tomáš
    In this article, an evaluation of the catecholase activity of the recently synthesized copper complexes towards dopamine is reported based on a comparison of the performance of two different techniques – UV-Vis spectrophotometry and hydrodynamic amperometry. The results obtained were confronted with those published for natural tyrosinase enzyme (isolated from mushroom 'Agaricus bisporus') and defined by Michaelis–Menten kinetics model. Besides a finding of comparable catalytic activity for the copper catalysts tested, it has to be emphasised that all the measurements have been performed in methanol, in which tyrosinase enzyme loses its catalytic activity.