Vývoj a aplikace technik ambientní hmotnostní spektrometrie

(CZ) Ambientní hmotnostní spektrometrie zahrnuje širokou skupinu metod umožňujících analýzu povrchu tuhých látek a kapalin v otevřeném prostoru vně hmotnostního spektrometru, kdy je vzorek přístupný k vnějšímu zásahu i během analýzy. Ambientní hmotnostní spektrometrie je dynamicky se rozvíjející oblastí analytické chemie. Umožňuje rychlou přímou analýzu objektů vně přístroje bez předchozí úpravy vzorku. V této práci byla studována desorpční ionizace elektrosprejem (DESI) a desorpční fotoionizace za atmosférického tlaku (DAPPI) se softwarově ovládanou polohou držáku vzorku. Tyto metody využívají sprejování rozpouštědel k desorpci a ionizaci analytu z pevného substrátu a jsou vhodné pro zobrazovací hmotnostní spektrometrii nízkomolekulárních organických sloučenin, kde je chemická identita molekul na povrchu analyzovaného objektu zkoumána jako funkce prostorové distribuce. Tento projekt se zabývá aplikacemi a instrumentálním vývojem. Pokud jde o aplikace, byla studována poloha hmyzích obranných žláz, separace lipidů v reálných vzorcích pomocí tenkovrstvé chromatografie (TLC), nebo metabolity steroidů v ženské moči v průběhu těhotenství. Ohledně instrumentálního vývoje, nejdůležitějším bodem byla konstrukce nového iontového zdroje pro ambientní zobrazovací hmotnostní spektrometrii neplanárních objektů....(EN) Ambient mass spectrometry defines the versatile group of methods providing analysis of solid sample surfaces and liquids in an open atmospheric pressure environment, where the sample is simultaneously accessible to another treatment. Ambient mass spectrometry is a sharply developing research area in the analytical chemistry. It provides fast, direct analysis of objects without any sample pretreatment with the use of the mass spectrometer. Desorption electrospray ionization (DESI) and desorption atmospheric pressure photoionization (DAPPI) equipped with software control of the sample holder were investigated in this doctoral thesis. These methods use a spray of solvents for desorption and ionization molecules from solid substrate and they are suitable tools for mass spectrometry imaging (MSI) of low molecular organic compounds, where the chemical identity of molecules present on a surface is examined as a function of spatial distribution. This project deals with applications and instrumental development. As for the applications, the position of the defense glands on insect bodies, separation of the lipids in complex mixtures on thin-layer chromatography (TLC) plates, or steroid metabolites in woman urine during pregnancy were thus investigated. As for the instrumental development, the most...Katedra analytické chemieDepartment of Analytical ChemistryPřírodovědecká fakultaFaculty of Scienc

Vývoj a aplikace technik ambientní hmotnostní spektrometrie

(CZ) Ambientní hmotnostní spektrometrie zahrnuje širokou skupinu metod umožňujících analýzu povrchu tuhých látek a kapalin v otevřeném prostoru vně hmotnostního spektrometru, kdy je vzorek přístupný k vnějšímu zásahu i během analýzy. Ambientní hmotnostní spektrometrie je dynamicky se rozvíjející oblastí analytické chemie. Umožňuje rychlou přímou analýzu objektů vně přístroje bez předchozí úpravy vzorku. V této práci byla studována desorpční ionizace elektrosprejem (DESI) a desorpční fotoionizace za atmosférického tlaku (DAPPI) se softwarově ovládanou polohou držáku vzorku. Tyto metody využívají sprejování rozpouštědel k desorpci a ionizaci analytu z pevného substrátu a jsou vhodné pro zobrazovací hmotnostní spektrometrii nízkomolekulárních organických sloučenin, kde je chemická identita molekul na povrchu analyzovaného objektu zkoumána jako funkce prostorové distribuce. Tento projekt se zabývá aplikacemi a instrumentálním vývojem. Pokud jde o aplikace, byla studována poloha hmyzích obranných žláz, separace lipidů v reálných vzorcích pomocí tenkovrstvé chromatografie (TLC), nebo metabolity steroidů v ženské moči v průběhu těhotenství. Ohledně instrumentálního vývoje, nejdůležitějším bodem byla konstrukce nového iontového zdroje pro ambientní zobrazovací hmotnostní spektrometrii neplanárních objektů....(EN) Ambient mass spectrometry defines the versatile group of methods providing analysis of solid sample surfaces and liquids in an open atmospheric pressure environment, where the sample is simultaneously accessible to another treatment. Ambient mass spectrometry is a sharply developing research area in the analytical chemistry. It provides fast, direct analysis of objects without any sample pretreatment with the use of the mass spectrometer. Desorption electrospray ionization (DESI) and desorption atmospheric pressure photoionization (DAPPI) equipped with software control of the sample holder were investigated in this doctoral thesis. These methods use a spray of solvents for desorption and ionization molecules from solid substrate and they are suitable tools for mass spectrometry imaging (MSI) of low molecular organic compounds, where the chemical identity of molecules present on a surface is examined as a function of spatial distribution. This project deals with applications and instrumental development. As for the applications, the position of the defense glands on insect bodies, separation of the lipids in complex mixtures on thin-layer chromatography (TLC) plates, or steroid metabolites in woman urine during pregnancy were thus investigated. As for the instrumental development, the most...Katedra analytické chemieDepartment of Analytical ChemistryFaculty of SciencePřírodovědecká fakult

Development and applications of ambient mass spectrometry techniques

(EN) Ambient mass spectrometry defines the versatile group of methods providing analysis of solid sample surfaces and liquids in an open atmospheric pressure environment, where the sample is simultaneously accessible to another treatment. Ambient mass spectrometry is a sharply developing research area in the analytical chemistry. It provides fast, direct analysis of objects without any sample pretreatment with the use of the mass spectrometer. Desorption electrospray ionization (DESI) and desorption atmospheric pressure photoionization (DAPPI) equipped with software control of the sample holder were investigated in this doctoral thesis. These methods use a spray of solvents for desorption and ionization molecules from solid substrate and they are suitable tools for mass spectrometry imaging (MSI) of low molecular organic compounds, where the chemical identity of molecules present on a surface is examined as a function of spatial distribution. This project deals with applications and instrumental development. As for the applications, the position of the defense glands on insect bodies, separation of the lipids in complex mixtures on thin-layer chromatography (TLC) plates, or steroid metabolites in woman urine during pregnancy were thus investigated. As for the instrumental development, the most..

Development and applications of ionization techniques in ambient mass spectrometry

Ambient mass spectrometry is a sharply developing subject area. Desorption electrospray ionization (DESI) and desorption atmospheric pressure photoionization (DAPPI) are two types of ionization techniques in the ambient mass spectometry. Herein, they were investigated in two research areas: (1) TLC analysis. (2) Localization of insect defense glands

Preparation of asymmetrically substituted diphenylacetylenes usable in molecular electronics

Preparation of asymetrically substituted diphenylacetylenes usable in molecular electronics Abstract This bachelor's work deals with synthesis of assymetrically substituted diphenylacetylenes and their transformation into (η4 -cyclobutadiene)-(η5 - cyclopentadienyl)cobalt complexes, which should be used and researched as molecular rotors. Multistep synthesis concerning conversion of primary arylamines into tertiary by N-permethylation, nucleophilic acyl substitution and Sonogashira coupling was prepared asymmetrically substituted diphenylacetylene with, which consequently underwent cycloaddition [2 + 2] with cyclopentadienyldicarbonylcobalt. Creating (η4 -cyclobutadiene)-(η5 -cyclopentadienyl)cobalt complexe was identified by MS. Keywords: diphenylacetylene, Sonogashira coupling, (η4 -cyclobutadiene)- (η5 -cyclopentadienyl)cobalt complex, cycloaddition [2 + 2], molecular roto

The use of ambient ionization techniques in mass spectrometry

Keywords: ambient ionization techniques; mass spectrometry; desorption electrospray ionization; desorption atmospheric pressure photoionization; thin layer chromatography; lipids, mass spectrometry imaging Ambient ionization technique in mass spectrometry is an ionization, which carries out in open space outside the machine and which does not require any, or only a minimal sample pretreatment. DESI (desorption electrospray ionization) and DAPPI (desorption atmospheric pressure photoionization) equipped with software control of the spray emitter position for analysis of low molecular organic compounds were investigated in this thesis. These methods use a spray of solvents for desorption and ionization molecules from solid substrate. Conditions for the successful analysis of phospholipids, wax esters and some other compounds were developed. Ambient ionization techniques were quantitatively compared. The application was HPTLC/DESI-MS of lipid's mixture and HPTLC/DAPPI-MS of vernix caseosa. DAPPI-MS was applied for the analysis of termites of Prorhinotermes genus (Isoptera, Rhinotermitidae). Pilot experiments of two dimensional analysis and mass spectrometry imaging were realized

The use of ambient ionization techniques in mass spectrometry

Keywords: ambient ionization techniques; mass spectrometry; desorption electrospray ionization; desorption atmospheric pressure photoionization; thin layer chromatography; lipids, mass spectrometry imaging Ambient ionization technique in mass spectrometry is an ionization, which carries out in open space outside the machine and which does not require any, or only a minimal sample pretreatment. DESI (desorption electrospray ionization) and DAPPI (desorption atmospheric pressure photoionization) equipped with software control of the spray emitter position for analysis of low molecular organic compounds were investigated in this thesis. These methods use a spray of solvents for desorption and ionization molecules from solid substrate. Conditions for the successful analysis of phospholipids, wax esters and some other compounds were developed. Ambient ionization techniques were quantitatively compared. The application was HPTLC/DESI-MS of lipid's mixture and HPTLC/DAPPI-MS of vernix caseosa. DAPPI-MS was applied for the analysis of termites of Prorhinotermes genus (Isoptera, Rhinotermitidae). Pilot experiments of two dimensional analysis and mass spectrometry imaging were realized

New Perspectives on the 143Nd/144Nd Palaeoceanographic Tracer on Foraminifera: The State‐of‐the‐Art Frontiers of Analytical Methods

Abstract The 143Nd/144Nd isotopic composition of foraminifera represents one of the most prominent palaeoceanographic proxies enabling tracing of particular water masses due to the short residence time of Nd in seawater and large‐scale provinciality resulting from its lithogenic origin. Despite its wide use, the applicability of foraminiferal Nd isotopic systematics as a palaeoceanographic tracer is largely hampered by the amount of material needed for precise analyses. Here, we analyzed for the first time foraminiferal samples of a combined weight of only ∼300–500 μg (ca. 300 pg to 1 ng Nd loaded). We followed a methodology that utilizes Nd separation from the matrix and provides precise 143Nd/144Nd determinations by thermal ionization mass spectrometry with sensitive 1013 Ω amplifiers. Two different techniques analyzing NdO+ and Nd+ (single/double filament configurations) were employed and tested to assess the limits both in terms of in‐run precision and accuracy concluding that the former method yielded an external reproducibility on the determined 143Nd/144Nd better than ∼90 ppm (2RSD; relative standard deviation) for 100 pg Nd loads. The overall veracity was tested by multiple analyses of Holocene and Miocene foraminifera from the Mediterranean region. Pooled data were obtained in agreement with previous studies attesting that multiple analyses of even very low Nd loads (≤1 ng) can lead to sufficient precision. As revealed by our newly obtained data, individual foraminiferal species show a significant naturally induced 143Nd/144Nd variability that needs to be considered when pursuing Nd isotopic analysis