28 (2022) Scientific papers, Series A
Permanentní URI k tomuto záznamuhttps://hdl.handle.net/10195/80387
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Článek Otevřený přístup peer-reviewedpublished Morin-modified carbon paste electrode as a promising tool for monitoring aluminium: An initial study(University of Pardubice, 2022) Švancara, Ivan; Kopecká, Nikol; Sýs, Milan; Adam, MartinThis article introduces spectrophotometric and electrochemical investigations of the complex-forming reaction between morin (MO) and the aluminium ions in mild acidic media. Already in the initial stage, the latter measurements have indicated that a carbon paste electrode bulk-modified with a small portion of MO could serve as a simple voltammetric sensor for indirect monitoring the Al(III) species in selected samples, such as some pharmaceutical products.Článek Otevřený přístup peer-reviewedpublished Catecholase biomimetic copper(II) complex immobilization via Schiff's base formation onto the cross-linked polymers prepared by drop-casting(University of Pardubice, 2022) Sýs, Milan; Bártová, Michaela; Hartmanová, Aneta; Mikysek, Tomáš; Adam, MartinIn this article, a universal protocol is introduced dealing with covalent immobilization of catecholase biomimetic copper(II) complexes with free carbonyl group onto the primary amine-based polymeric substrates (chitosan and collagen, type II) cross-linked with glutar-aldehyde; both being enabled via Schiff's base formation. As a representative of biomimetic catalysts, [Cu2Ac2O(L)ClO4] consisting of a 2,6-bis(4-methyl piperazin-1-ylmethyl)- 4-formyl-phenoxy ligand (L) was selected. The resulting functionalized polymers formed at the surface of a screen-printed carbon electrode were characterized using scanning electron microscopy with energy dispersive X-ray analysis. As a result, the procedure presented herein could find use in the development of artificial biosensors.Článek Otevřený přístup peer-reviewedpublished Moisture sorption properties of matcha tea powder as affected by high humidity storage(University of Pardubice, 2022) Červenka, Libor; Palarčík, Jiří; Zeman, Vojtěch; Muriqi, Sali; Adam, MartinThe effect of high relative humidity (RH) storage on the subsequent moisture sorption of matcha tea powder was examined. The sample of interest was stored above silicagel (control), at 52.9 and 75.3 % RH for two months at 25 °C. Moisture adsorption and desorption experiments were performed using a dynamic vapor system, and the sigmoid-shaped (type II) isotherms obtained with the aid of multi-Freundlich equation. Hysteresis loop disappeared for powder samples previously exposed to high humidity environment. According to Caurie and multi-Freundlich equations, higher critical values of aw, monolayer content, number of monolayers, and surface area of adsorption were observed for the samples stored under high RH. The change in the particle size distribution was also discussed.Článek Otevřený přístup peer-reviewedpublished Changes in concentrations of 5-hydroxymethylfurfural, carbohydrates, and ethanol during the mead production(University of Pardubice, 2022) Klikarová, Jitka; Melicharová, Šárka; Řezková, Soňa; Česlová, Lenka; Adam, MartinThis work is focused on monitoring changes in the concentrations of 5-hydroxymethylfurfural, ethanol, and carbohydrates during the mead production using various analytical techniques, namely micellar electrokinetic chromatography with spectrophotometric detection, gas chromatography coupled to flame-ionization detector, and hydrophilic interaction liquid chromatography with refractive-index detector, respectively. In this study, production of three mead samples made by different Czech beekeepers has been monitored. The individual mead fractions were regularly sampled for two months of fermentation and always analysed with the aid of the optimised analytical approach.Článek Otevřený přístup peer-reviewedpublished Determination of α-tocopherol in different biological samples by GC-MS without derivatization(University of Pardubice, 2022) Kopčil, Michal; Janeček, Radim; Kanďár, Roman; Adam, MartinA method has been developed to determine the levels of α-tocopherol in human plasma and colon tissue using gas chromatography with mass spectrometric detection. The samples were acquired from 27 patients with Crohn’s disease. Samples were deproteinized and α-tocopherol was obtained using a two-step extraction and measured by GC-MS without prior derivatization. The analytical parameters of the method were satisfactory: the intra-day and inter-day coefficients of variation were below 7% and quantitative recoveries range between 92.2-100.5%. The method shows an excellent linear range from 0.6-64.3 μmol/L. The median measured α-tocopherol concentration in human plasma was 21.6 μmol/L and in healthy colon tissue and tissue affected by Crohn’s disease was 26.5 nmol/mg and 34.9 nmol/mg, respectively. We did not find any statistically significant correlation or differences between the α-tocopherol content in plasma and tissue. Overall, our method has potential to be easily implemented in special studies for monitoring α-tocopherol as a biomarker of oxidative stress.Článek Otevřený přístup peer-reviewedpublished Gadolinium of anthropogenic origin in food crops(University of Pardubice, 2022) Josefová, Dominika; Mišíková, Frederika; Krejčová, Anna; Patočka, Jan; Adam, MartinThe study is focused on the monitoring of rare earth elements (REE) in food crops with particular interest paid to the evaluation of gadolinium of anthropogenic origin. Macroscopic fungi were used as they are culinary processed and being also a good indicator of environmental pollution. In total, 46 dried mushroom samples originating from the Czech Republic and Slovakia were analysed. When using microwave decomposition of samples and the elemental analysis of Ce, Dy, Er, Eu, Gd, Ho, La, Lu, Nd, Pr, Sm, Tb, Tm, Y, Yb using inductively coupled plasma mass spectrometry (ICP-MS), the respective analytical procedure was optimised and validated. The study also included the calculation of the gadolinium anomaly in the processed samples, as well as the calculation of the amount of anthropogenic gadolinium. In the case of the gadolinium monitored, the minimum value found was 1.41 μg kg−1; the maximum being 361 μg kg−1, and the average 33.7 μg kg−1. The contribution of gadolinium of the anthropogenic origin ranged from 0.77 to 270 g kg−1.Článek Otevřený přístup peer-reviewedpublished Voltammetric behavior of indole-3-butyric acid and a novel approach for its determination in mixture with indole-3-acetic acid using boron-doped diamond electrode as a sensor(University of Pardubice, 2022) Chýlková, Jaromíra; Janíková, Lenka; Jehlička, Vladimír; Šelešovská, Renáta; Adam, MartinIn the present paper, the voltammetric behavior of indole-3-butyric acid (IBA) is described employing a boron-doped diamond electrode (BDDE). In acidic media, IBA exhibited one well-developed oxidation signal. Two voltammetric methods, linear-sweep (LSV) and differential pulse voltammetry (DPV), were optimized and low limits of quantification obtained (0.79 μg mL−1 for LSV and 0.52 μg mL−1 for DPV). The latter technique with optimized parameters was successfully applied to the determination of IBA in growth stimulation formulas. Moreover, simultaneous voltammetric determination of IBA and other auxin phytohormone, indole-3-acetic acid (IAA), employing BDDE was also examined. Despite their similar structures, a simple method based on DPV and derivatization of a selected part of the obtained curves was developed. It has been proven that simultaneous determination of IBA and IAA is possible at various concentration ratios with satisfactory results. Applicability of the proposed method was verified by successful analysis of the growth stimulation preparation containing IBA or a mixture of the auxins studied.Článek Otevřený přístup peer-reviewedpublished Waste textile processing and its impact on the environment(University of Pardubice, 2022) Audrlická Vavrušová, Lenka; Zídková, Petra; Krejčová, Anna; Adam, MartinThe work is focused on mapping the current state of waste textile management, its possible further processing in the Czech Republic and its environmental impact assessment. More specifically, it deals with the topic of sustainability in the textile industry, textile waste in terms of legislation, and environmental impact assessment using the Life Cycle Assessment (LCA) method. Also, it maps the situation in waste management in the Czech Republic and makes comparison with data available for the European Union (EU). Data collection on textile waste management was performed. The data are further used in LCA analysis and waste treatment methods are evaluated in terms of environmental impact using GaBi software. The lowest environmental impacts are associated with the re-wearing of waste textiles. A secondary production of cleaning cloths, as well as disposal by incineration or landfilling, are more demanding for the environment. In comparison with data from other European countries, the efficiency of textile waste management ranks the Czech Republic to the forefront in the EU. The most beneficial and cheapest solution of the problem, not only in the management of textile waste, is to reduce the production of goods, the supply of producers, and strengthen market requirements so that waste is generated as little as possible. Then, there will be no need to seek a solution to dispose of excess waste.Článek Otevřený přístup peer-reviewedpublished Advances in perovskite doping – SrTiO3 with cobalt ions(University of Pardubice, 2022) Fejk, Jiří; Dohnalová, Žaneta; Honcová, Pavla; Adam, MartinThis paper supports the point of research on doping of inorganic materials – in this case, pigments – with various elements. Compounds on the basis of SrTiO3 with individually substituted titanium positions for the cobalt ions have been prepared by the solid-state reaction boosted by the prior-to-made mechanoactivation. Calcination temperature and the molar ratio of reactants were varied in order to study their effect on the pigment synthesis. Powdered materials were characterised in terms of thermal behaviour and the phase composition. Particle size distribution and application possibilities in ceramic glaze and organic binder along with colour properties were subsequently determined for selected samples. The prepared set of pigments SrTi1–xCoxO3 (x = 0.1–0.9) differed in characteristics according to a diverse range of substitution and conditions of the synthesis.Článek Otevřený přístup peer-reviewedpublished Synthesis and antiproliferative activity of the salicyl-based Weinreb amides and their derivatives in cancer cell lines(University of Pardubice, 2022) Pilařová, Eliška; Jorda, Radek; Svobodová, Klára; Pauk, Karel; Kryštof, Vladimír; Imramovský, Aleš; Adam, MartinA series of 11 pseudotripeptide Weinreb amides and 8 pseudodipeptide sulfonylhydrazides were synthesized and assessed using the resazurin-based method to determine their antiproliferative activity against the following cancer cell lines: lymphoblastic leukaemia (CEM), acute myeloid leukaemia (MV4-11), multiple myeloma (U266), and breast adenocarcinoma (MCF-7). The investigated compounds have shown a mid-micromolar range of inhibition. When L-Trp was included in the centre of the tripeptide chain, the derivatives exhibited a single-digit micromolar activity against the MV4-11 and U266 cell lines. Further immunoblotting experiments and caspase-3/7 activity assays for the most active compound 3e have confirmed apoptosis as the mechanism of cell death.