Publications by authors named "Michal Voldrich"

DART (direct analysis in real time), a novel technique with wide potential for rapid screening analysis, coupled with high-resolution time-of-flight mass spectrometry (TOF-MS) has been used for quantitative analysis of 5-hydroxymethylfurfural (5-HMF), a typical temperature marker of food. The DART/TOF-MS method was optimised and validated. Quantification of 5-HMF was achieved by use of a stable isotope-labelled 5-HMF standard prepared from glucose.

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Phytic acid (PA) and lower inositolphosphates (InsP(n) ) is the main storage form of phosphorus in grains or seeds. The content of PA and InsP(n) in different varieties of barley was analyzed by capillary isotachophoresis and online-coupled capillary isotachophoresis with CZE. The electrolytes (in demineralized water) for the isotachophoretic analysis consisted of 10 mM HCl, 14 mM glycylglycine, and 0.

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Potatoes, members of the Solanaceae plant family, contain calystegines, water-soluble nortropane alkaloids, which are biologically active as glycosidase inhibitors. The content of calystegines A(3) and B(2) in different varieties of potato and in various parts of the tubers (whole potato, peel, flesh, and sprouts) were analysed by new capillary zone electrophoresis and capillary isotachophoresis methods and by the routine GC method. The optimized background electrolyte for capillary zone electrophoretic analysis was mixture of 20 mM histidine, 20 mM N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid and 20% (v/v) methanol in demineralized water.

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An on-line coupled capillary isotachophoresis-capillary zone electrophoresis method for the determination of glycyrrhizin in liqueurs is described. The optimised electrolyte system was 5 mM HCl+11 mM epsilon-aminocaproic acid+0.05% hydroxyethylcellulose+30% methanol (leading electrolyte), 5 mM caproic acid+30% methanol (terminating electrolyte) and 20 mM caproic acid+10 mM histidine+0.

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An on-line coupled capillary isotachophoresis--capillary zone electrophoresis (cITP-CZE) method for the determination of domoic acid in shellfish and algae is described. The optimised cITP-CZE electrolyte system was 10 mM HCl + 20 mM beta-alanine (BALA) + 0.05% hydroxyethylcellulose (leading electrolyte), 5 mM caproic acid (terminating electrolyte) and 20 mM caproic acid + 20 mM BALA + 0.

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A capillary zone electrophoresis (CZE) method with conductometric detection of biogenic amines (cadaverine, putrescine, agmatine, histamine, tryptamine and tyramine) is described. The optimised background electrolyte was the following: 15 mM histidine + 5 mM adipic acid + 1.5 mM sulphuric acid + 0.

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Butorphanol tartrate is a synthetic opioid agonist-antagonist used as analgesic, possessing three chiral centres in the basic part of the molecule. Its chiral purity is routinely controlled only by optical rotation. A new capillary zone electrophoresis method, capable to separate the enantiomers of butorphanol and intermediate of its synthesis, cycloamine, was developed.

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L-Carnitine is a substance natural for human body which transfers fatty acids to the place of burning-mitochondria and aids the transformation of fats into energy and this way supports overweight reduction and immediate physical performance, increases resistance from physical load and protect heart from overload. In this study are described newly developed electrophoretic methods (ITP, CZE with direct and/or indirect UV detection) for carnitine determination in various samples. The results were compared with results obtained by validated HPLC method.

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