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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
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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 ...
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 ...
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. ...
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 ...
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 ...
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 ...
Aldrithiol-2 as a new derivatization agent for double bond localization in unsaturated compounds by mass spectrometry
Strmeň, Timotej; Cvačka, Josef
2019 - English
A new method for localizing double bonds in lipids using derivatization with 2,2'-clipyridyl disulfide (Aldrithio-2) and electrospray ionization mass spectrometry (EST-MS) is presented. The derivatization introduces a permanent charge to the molecules. When collisionally activated, the derivatives provide diagnostic peaks useful for establishing the position of the original double bond. Since permanent charge of the derivative significantly increases the detectability of analytes, the method works well also for of very low polarity like hydrocarbons.
Keywords:
aldrithiol-2; double bond; electrospray; lipids; mass spectrometry
Available at various institutes of the ASCR
Aldrithiol-2 as a new derivatization agent for double bond localization in unsaturated compounds by mass spectrometry
A new method for localizing double bonds in lipids using derivatization with 2,2'-clipyridyl disulfide (Aldrithio-2) and electrospray ionization mass spectrometry (EST-MS) is presented. The ...
Monitoring of enzymatic enantioselective acetylation of gem-difluorinated alcohols by capillary electrophoresis
Šolínová, Veronika; Pomeisl, Karel; Lamatová, Nikola; Pohl, Radek; Brabcová, Jana; Krečmerová, Marcela; Kašička, Václav
2018 - English
A new fast and highly efficient capillary electrophoretic (CE) method has been developed for chiral analysis of non-charged gem-difluorinated alcohol (3-(benzyloxy)-1,1-difluoro-propan-2-ol) using sulfobutylether-β-CD as chiral selector. The method was applied for monitoring of enzymatic (lipase mediated) enantioselective acetylation of the above alcohol and for determination of enantiomeric purity of both substrates and products of the enzymatic reaction.
Keywords:
enantioselective acetylation; difluorinated alcohols; capillary electrophoresis
Available at various institutes of the ASCR
Monitoring of enzymatic enantioselective acetylation of gem-difluorinated alcohols by capillary electrophoresis
A new fast and highly efficient capillary electrophoretic (CE) method has been developed for chiral analysis of non-charged gem-difluorinated alcohol (3-(benzyloxy)-1,1-difluoro-propan-2-ol) using ...
Affinity capillary electrophoresis applied to chiral separations of diquats and to determination of the stability constants of their complexes with sulfated cyclodextrins
Kašička, Václav; Bílek, Jan; Koval, Dušan; Sázelová, Petra; Talele, Harish Ramesh; Severa, Lukáš; Reyes Gutierrez, Paul Eduardo; Teplý, Filip
2018 - English
Affinity capillary electrophoresis (ACE) using an aqueous 22/35 mM sodium/phosphate buffer, pH 2.5, as the background electrolyte (BGE), and 6 mM randomly highly sulfated alpha-, beta- and gamma-cyclodextrins (CDs) as chiral selectors has been successfully applied for separation of (P)- and (M)-enantiomers of a series of eleven new diquats (DQs) and for estimation of the strength of their complexes with the above CDs. The apparent stability constants of the DQs-CDs complexes were determined from the simultaneous ACE measurements of the dependence of effective electrophoretic mobilities of (P)- and (M)-enantiomers of DQs on the concentrations of CDs in the BGE by nonlinear regression analysis. The DQs enantiomers formed strong complexes with all three types of CDs with the apparent stability constants in the range (7.80 547.4) × 103 L/mol.
Keywords:
affinity capillary electrophoresis; chiral separations; diquats
Available at various institutes of the ASCR
Affinity capillary electrophoresis applied to chiral separations of diquats and to determination of the stability constants of their complexes with sulfated cyclodextrins
Affinity capillary electrophoresis (ACE) using an aqueous 22/35 mM sodium/phosphate buffer, pH 2.5, as the background electrolyte (BGE), and 6 mM randomly highly sulfated alpha-, beta- and ...
Determination of stability constants of antamanide complexes with sodium and potassium ions by affinity capillary electrophoresis
Pangavhane, Sachin; Böhm, S.; Makrlík, E.; Ruzza, P.; Kašička, Václav
2018 - English
Affinity capillary electrophoresis (ACE) was applied for quantitative investigation of the interactions between important biomolecule, cyclic decapeptide antamanide (AA), cycl[-Val(1)-Pro(2)-Pro(3)-Ala(4)-Phe(5)-Phe(6)-Pro(7)-Pro(8)-Phe(9)-Phe(10)-], and sodium and potassium cations in methanol. Apparent stability constants of AA complexes with these alkali metal ions were determined from the dependence of effective mobility of AA on the concentration of these ions in the background electrolyte by the non-linear regression analysis. The AA complexes with Na+ and K+ ions were found to be relatively weak, with the apparent stability constants 343 L/mol and 35 L/mol, respectively.
Keywords:
affinity capillary electrophoresis; antamanide; binding constant
Available at various institutes of the ASCR
Determination of stability constants of antamanide complexes with sodium and potassium ions by affinity capillary electrophoresis
Affinity capillary electrophoresis (ACE) was applied for quantitative investigation of the interactions between important biomolecule, cyclic decapeptide antamanide (AA), ...
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