Characterization of Ca2+ binding properties of human ameloblastin I and II isoforms and ameloblastin C-term proteins by capillary electrophoresis
Sázelová, Petra; Vetýšková, Veronika; Boušová, Kristýna; Vondrášek, Jiří; Kašička, Václav
2022 - English Keywords: calcium ion; capillary electrophoresis; human ameloblastin Available at various institutes of the ASCR Characterization of Ca2+ binding properties of human ameloblastin I and II isoforms and ameloblastin C-term proteins by capillary electrophoresis

Sázelová, Petra; Vetýšková, Veronika; Boušová, Kristýna; Vondrášek, Jiří; Kašička, Václav
Ústav organické chemie a biochemie, 2022

Study of complexation of 5-phenylazopyrimidines with β-cyclodextrin by affinity capillary electrophoresis
Štěpánová, Sille; Procházková, Eliška; Hruzíková, Anna; Čechová, Lucie; Janeba, Zlatko; Kašička, Václav
2022 - English Keywords: affinity capillary electrophoresis; β-cyclodextrin; 5-phenylazopyrimidines Available at various institutes of the ASCR Study of complexation of 5-phenylazopyrimidines with β-cyclodextrin by affinity capillary electrophoresis

Štěpánová, Sille; Procházková, Eliška; Hruzíková, Anna; Čechová, Lucie; Janeba, Zlatko; Kašička, Václav
Ústav organické chemie a biochemie, 2022

Hmotnostně spektrometrické zobrazování
Vrkoslav, Vladimír; Strnad, Štěpán; Kučera, L.
2022 - Czech Těžiště kurzu bude v MALDI hmotnostním zobrazování. V první části budou shrnuty poznatky a postupy přípravy vzorků, nanášení matrice, měření a vyhodnocováním MALDI MSI analýz. Následovat bude blok věnovaný praktickým zkušenostem MALDI MSI lipidů, metabolitů a dalších analytů na tkáňových řezech a jiných planárních površích. Závěr bude věnován molekulovému zobrazování s využitím dalších používaných ionizačních technik (DESI, DAPPI, LAESI, atd.). The course will focus on MALDI mass spectrometry imaging. Knowledge and procedures of sample preparation, matrix application, measurement, and evaluation of MALDI MSI will be summarized. The first part will be followed by a block dedicated to the practical experience of MALDI MSI of lipids,metabolites, and other analytes on tissue sections and other planar surfaces. We will also explain MSI by other ionization techniques (DESI, DAPPI, LAESI, etc.) Keywords: MALDI - MSI; DESI; sample preparation Available at various institutes of the ASCR Hmotnostně spektrometrické zobrazování

Těžiště kurzu bude v MALDI hmotnostním zobrazování. V první části budou shrnuty poznatky a postupy přípravy vzorků, nanášení matrice, měření a vyhodnocováním MALDI MSI analýz. Následovat bude blok ...

Vrkoslav, Vladimír; Strnad, Štěpán; Kučera, L.
Ústav organické chemie a biochemie, 2022

A new method for double bond characterization in lipids by ultraviolet photodissociation mass spectrometry
Rumlová, Barbora; Strmeň, T.; Cvačka, Josef
2021 - English Lipids are structurally diverse biomolecules with vital functions in biological systems. Some of these functions are closely associated with the specific location of the carbon-carbon double bond in the lipid acyl chains. The chain length and the number of unsaturated carbon-carbon bonds can be determined using conventional MS/MS-based structural elucidation methods employing low or higher energy collision-induced dissociation. However, these dissociation techniques do not provide more subtle structural details, for example, the position of unsaturated bonds. Another type of activation method – ultraviolet photodissociation can be used for this purpose. In this study, a new method for characterization of double bond location in lipids acyl chain was developed using 193 nm ultraviolet photodissociation implemented on Orbitrap Fusion Lumos mass spectrometer. This approach is based on the derivatization of the double bond with bis-(5-iodo-[2]pyridyl)-disulfide, subsequent specific cleavages provide a unique diagnostic pair bearing information about the double bond position. Keywords: double bond; lipids; mass spectrometry; ultraviolet photodissociation Fulltext is available at external website. A new method for double bond characterization in lipids by ultraviolet photodissociation mass spectrometry

Lipids are structurally diverse biomolecules with vital functions in biological systems. Some of these functions are closely associated with the specific location of the carbon-carbon double bond in ...

Rumlová, Barbora; Strmeň, T.; Cvačka, Josef
Ústav organické chemie a biochemie, 2021

Copper complexes with triazoles
Jaklová Dytrtová, Jana; Jakl, M.
2020 - English Triazoles are artificial chemicals used as fungicides as well as for pharmaceutical treatment. However, their reactivity is highly influenced by the presence of other chemicals. Especially, the presence of copper cations changes the reactivity of triazole by theoretically unexpected way. We have studied the interactions of the triazole ring with copper cations to help explain the reactivity of triazoles as a group. Keywords: triazoles; Cu(I); Cu(II); mass spectrometry; ESI-MS; complexes Available at various institutes of the ASCR Copper complexes with triazoles

Triazoles are artificial chemicals used as fungicides as well as for pharmaceutical treatment. However, their reactivity is highly influenced by the presence of other chemicals. Especially, the ...

Jaklová Dytrtová, Jana; Jakl, M.
Ústav organické chemie a biochemie, 2020

Separation of triazoles from real samples with capillary electrophoresis
Kovač, Ishak; Jakl, M.; Šolínová, Veronika; Jaklová Dytrtová, Jana
2020 - English The CE has become one of the advantageous tools in fungicides analysis in complex matrices due to its simplicity and separation efficiency. The separation of a group of thee triazole (i.e. penconazole, tebuconazole, and cyproconazole) fungicides was achieved with CD-MEKC with anionic Sg-CD as a selector at pH=4,8. The background electrolyte consisted of TRIS phosphate buffer (50 mmol/L) and 15 mmol/L SDS. The separation was performed on uncoated fused silica capillary with 500/425 mm (total/effective) length under -15 kV separation voltage. Achieved LOD values with this method were: 0,73, 1,88, 0,60, 1,18 (umol/L) for penconazole, tebuconazole, cyproconazole A and B respectively. Keywords: capillary electrophoresis; penconazole; tebuconazole; cyproconazole; γ-cyclodextrin Available at various institutes of the ASCR Separation of triazoles from real samples with capillary electrophoresis

The CE has become one of the advantageous tools in fungicides analysis in complex matrices due to its simplicity and separation efficiency. The separation of a group of thee triazole (i.e. ...

Kovač, Ishak; Jakl, M.; Šolínová, Veronika; Jaklová Dytrtová, Jana
Ústav organické chemie a biochemie, 2020

Tebuconazole and its behaviour in the presence of magnesium
Jakl, M.; Jaklová Dytrtová, Jana
2020 - English Tebuconazole is a fungicide frequently used in agriculture. Its possible impact to (non-)target species is influenced by its presence. Moreover, the presence of triazoles in soil has an impact to bioavailability of nutrients. This study brings the information potentially useful in the evaluation of tebuconazole fate in the environment. The studies based on the electrospray gas phase experiments provide an estimation of the tebuconazole ability to create complexes with magnesium. Keywords: triazoles; Mg(II); mass spectrometry; ESI-MS; complexes Available at various institutes of the ASCR Tebuconazole and its behaviour in the presence of magnesium

Tebuconazole is a fungicide frequently used in agriculture. Its possible impact to (non-)target species is influenced by its presence. Moreover, the presence of triazoles in soil has an impact to ...

Jakl, M.; Jaklová Dytrtová, Jana
Ústav organické chemie a biochemie, 2020

Structural characterization of fatty acids with triple bond and unusual double bond positions by HPLC/APCI-MS2
Horká, Petra; Vrkoslav, Vladimír; Cvačka, Josef
2019 - English Fatty acid methyl esters (FAMEs) were analyzed by reversed-phase HPLC coupled to atmospheric pressure chemical ionization (APCI) mass spectrometry. Acetonitrile was used as mobile phase. The gas-phase reactions of acetonitrile and unsaturated FAMEs in the APCI source provided [M + C3H5N]+• adducts. Subsequent MS/MS analysis of these ions gave diagnostic fragments. The formation and fragmentation of the acetonitrile-related adducts were utilized for the structural characterization of FAME with isolated double bonds in (Z)-9,19-hexacosadienoic acid methyl ester, FAME with conjugated double bonds in (Z)-9,11-octadecadienoic acid methyl ester and FAME with a triple bond in 9-octadecynoic acid methyl ester. Keywords: acetonitrile-related adducts; acetylenic lipids; multiple bond localization; mass spectrometry Available at various institutes of the ASCR Structural characterization of fatty acids with triple bond and unusual double bond positions by HPLC/APCI-MS2

Fatty acid methyl esters (FAMEs) were analyzed by reversed-phase HPLC coupled to atmospheric pressure chemical ionization (APCI) mass spectrometry. Acetonitrile was used as mobile phase. The gas-phase ...

Horká, Petra; Vrkoslav, Vladimír; Cvačka, Josef
Ústav organické chemie a biochemie, 2019

Lokalizace poloh dvojných a trojných vazeb u methylesterů mastných kyselin pomocí HPLC/APCI-MS2
Horká, Petra; Vrkoslav, Vladimír; Cvačka, Josef
2019 - Czech Poloha a počet dvojných vazeb v alifatickém řetězci ovlivňuje fyzikální, chemické a biologické vlastnosti lipidů, avšak jednoznačné určení poloh těchto násobných vazeb je problematické. V roce 2012 byla publikována metoda kapalinové chromatografie s chemickou ionizací za atmosférického tlaku s hmotnostní detekcí (HPLC/APCI-MS) [1] vhodná pro analýzu polohy dvojných vazeb využívající tvorby molekulových aduktů [M + C3H5N]+. při APCI za přítomnosti acetonitrilu. Methylestery mastných kyselin (FAMEs) byly analyzovány HPLC/APCI-MS2 se 100% acetonitrilem jako mobilní fází. Při APCI docházelo v plynné fázi k tvorbě reaktivních částic, vznikajících ze složek mobilní fáze, které se vázaly na násobné vazby v alifatickém řetězci FAMEs za vzniku aduktu [M + C3H5N]+.. Kolizně indukovanou disociací (CID) aduktu [M + C3H5N]+., se získaly diagnostické fragmenty určující polohu (polohy) násobných vazeb. Zmíněná metoda byla evaluována pro běžně analyzované polynenasycené FAMEs s tradiční polohu dvojných vazeb (methylene-interrupted). Keywords: acetonitrile-related adducts; multiple bond localization Available at various institutes of the ASCR Lokalizace poloh dvojných a trojných vazeb u methylesterů mastných kyselin pomocí HPLC/APCI-MS2

Poloha a počet dvojných vazeb v alifatickém řetězci ovlivňuje fyzikální, chemické a biologické vlastnosti lipidů, avšak jednoznačné určení poloh těchto násobných vazeb je problematické. V roce 2012 ...

Horká, Petra; Vrkoslav, Vladimír; Cvačka, Josef
Ústav organické chemie a biochemie, 2019

Method optimization for simultaneous separation of six triazole fungicides in HPLC
Kovač, Ishak; Martín Miján, P.; Del Sol Vega Alegre, M.; Dejmková, H.; Jaklová Dytrtová, Jana; Schwarzová, K.
2019 - English Triazole pesticides are widely used in agriculture against fungi pathogens. Their application is not restricted on just one member of the group, more importantly, the application is usually carried out in the mixture of two or more triazoles. Hence, this work focuses on simultaneous separation and detection of six triazole fungicides: penconazole, tebuconazole, propiconazole, cyproconazole, fenbuconazole, and difenoconazole. Two different columns were tested with different parameters for isocratic and gradient elution in HPLC with UV detector. On Purospher Reverse Phase-18 column with gradient elution isomers of triazoles cyproconazole and propiconazole were successfully separated. However, on this column, there was an overlap of some triazoles. In contrast, the isocratic elution on Kromasil Eternity-5-PhenylHexyl column showed sufficient separation capabilities. In further research, chiral separation of triazoles will be considered using capillary electrophoresis. Keywords: capillary electrophoresis; HPLC; triazole pesticides Available at various institutes of the ASCR Method optimization for simultaneous separation of six triazole fungicides in HPLC

Triazole pesticides are widely used in agriculture against fungi pathogens. Their application is not restricted on just one member of the group, more importantly, the application is usually carried ...

Kovač, Ishak; Martín Miján, P.; Del Sol Vega Alegre, M.; Dejmková, H.; Jaklová Dytrtová, Jana; Schwarzová, K.
Ústav organické chemie a biochemie, 2019