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    Tytuł:
    Nanomateriały w spektrometrii mas z laserową desorpcją/jonizacją wspomaganą powierzchnią
    Nanomaterials applied in surface-assisted laser desorption/ionization mass spectrometry
    Autorzy:
    Arendowski, Adrian
    Powiązania:
    https://bibliotekanauki.pl/articles/2200434.pdf
    Data publikacji:
    2022
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    laserowa desorpcja/jonizacja
    metody bezmatrycowe
    nanocząstki
    SALDI
    spektrometria mas
    laser desorption/ionization
    mass spectrometry
    matrix-free methods
    nanoparticles
    Opis:
    Laser desorption/ionization (LDI) is one of the most popular ionization techniques currently used in mass spectrometry (MS). This technique is most commonly used in a variant of matrix-assisted laser desorption/ionization (MALDI), which uses low molecular weight organic acid mixed with the sample to support the ionization process. However, this approach has some shortcomings such as: high chemical background in the spectral region below m/z 700 making it difficult to analyze compounds giving signals in this spectral region, inhomogeneous co-crystallization of analyte and matrix leading to the formation of so-called "sweet spots", i.e. inhomogeneous distribution of analyte in the crystallizing matrix. For these reasons, increasing research attention is focused on the possibilities offered by the use of matrix-free systems based on nanostructures in laser methods, which are referred to as surface-assisted laser desorption/ionization (SALDI). The use of nanostructures in LDI MS has made it possible to analyze low molecular compounds, often at very low concentrations, without the presence of matrix-derived chemical background, contributing to more applications of the LDI MS method. This work describes what the SALDI technique is and reviews the nanomaterials used in different variations of the approach. Among the described materials used in SALDI there are nanomaterials based on carbon and silicon, including the DIOS method, as well as techniques based on nanoparticles of gold, silver, platinum and titanium oxide. For each method, application examples are given for the detection of different classes of chemical compounds, often also in complex biological mixtures.
    Źródło:
    Wiadomości Chemiczne; 2022, 76, 9-10; 735--754
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Zastosowanie technik laserowej desorpcji/jonizacji w identyfikacji lipidów jako biomarkerów raka prostaty
    Application of laser desorption/ionization techniques in the identification of lipids as prostate cancer biomarkers
    Autorzy:
    Buszewska-Forajta, Magdalena
    Pomastowski, Paweł Piotr
    Maślak, Ewelina
    Fijałkowski, Piotr
    Buszewski, Bogusław
    Powiązania:
    https://bibliotekanauki.pl/articles/1413254.pdf
    Data publikacji:
    2021
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    laserowa desorpcja/jonizacja
    LDI
    lipidy
    biomarker
    rak prostaty
    laser desorption/ionization
    lipids
    prostate cancer
    Opis:
    Mass spectroscopy has grown enormously over the past century and its variations are used in many fields. One of the methods used to ionize particles is to irradiate the sample with laser radiation. This methods are called laser desorption/ionization techniques and they have great potential for diagnostic applications. Thanks to the so-called soft ionization, direct analysis of a wide variety of compound classes can be used for rapid profiling. Lipids are a diverse group of metabolites that share a common feature of having a hydrophobic fragment. They play an important role in various cellular processes. Changes in lipidome correlate with the symptoms of various diseases. The observation of abnormalities in lipid metabolism is especially important in cancers diagnosed in many patients - such as prostate cancer. Monitoring the level of key biomarkers in the development of a given disease will allow for an earlier correct diagnosis and the use of individual treatment. This short review presents the issues of prostate cancer and the applicability of laser desorption/ionization techniques to identify lipid biomarkers that can be used for rapid identification.
    Źródło:
    Wiadomości Chemiczne; 2021, 75, 7-8; 893-909
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Spektrometria mas w analizie białek i peptydów : znaczniki jonizacyjne
    Mass spectrometry in analysis of peptides and proteins : ionization markers
    Autorzy:
    Bąchor, R.
    Biernat, M.
    Cebrat, M.
    Kijewska, M.
    Kluczyk, A.
    Kuczer, M.
    Paluch, A.
    Waliczek, M.
    Wierzbicka, M.
    Stefanowicz, P.
    Szewczuk, Z.
    Powiązania:
    https://bibliotekanauki.pl/articles/171509.pdf
    Data publikacji:
    2018
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    spektrometria mas
    modyfikacje potranslacyjne
    znaczniki jonizacyjne
    fosforylacja
    glikacja
    biblioteki kombinatoryczne
    mass spectrometry
    post-translational modifications
    ionization markers
    phosphorylation
    glycation
    combinatorial libraries
    Opis:
    High sensitivity, accuracy, and ability to provide structural information makes mass spectrometry (MS) the method of choice for both qualitative and quantitative analysis in proteome research. Peptide sequencing by tandem mass spectrometry (MS/MS) was successfully applied to discover new peptide sequences and modifications. Insufficient ionization of some peptides is one of the main limitations of MS- based peptide identification. The development of sensitive detection techniques for the efficient analysis of such samples is very important. Differences in ionizability cause difficulties in quantification studies, which could be overcome by derivatization of peptides to improve both the detectability and the selectivity of an analysis. Incorporation of ionization markers and isotopic labels (particularly the isobaric tags) is often used for this reason. Isobaric labeling reagents (including commercially available iTRAQ, TMT, DiLeu and DiART) have found a wide application in quantitative proteomics. Mass spectrometry is a very good tool for the determination of posttranslational modifications (PTMs), but the modified proteins are usually present in low concentrations. The development of ionization tags specific to a particular PTM and suitable for sensitive analysis of the modified proteins is required. For the analysis of phosphorylated peptides, a combination of β-elimination and the reaction of resulting α,β-dehydroamino acid residues with the nucleophilic thiol group could be used to detect a labile PTM. Such reaction may be used to introduce derivatizing reagents at the original site of phosphorylation, to enhance ionization in MS analysis. Glycation and glycosylation of proteins are other very important PTMs associated with many natural processes as well as diseases. We have designed and synthesized bifunctional quaternary ammonium salt derivatives of phenylboronic acids for selective detection of carbohydrates and peptide-derived Amadori products by ESI-MS. The attachment of a fixed charge (e.g. in a form of a quaternary ammonium salt) to the amino groups in peptides leads to the enhancement of a precursor ion signal in mass spectra. We have developed several new QAS-containing ionization reagents including bicyclic tags with DABCO, ABCO or azoniaspiro groups. It is worth noting that 2,4,6-substituted pyrylium salts react with amino groups in peptides introducing a stable positive charge and improve peptide detection by MS. The newly developed ionization tags were successfully applied for the analysis of OBOC combinatorial libraries as well as for studying possible biomarkers of preeclampsia, a pregnancy disorder.
    Źródło:
    Wiadomości Chemiczne; 2018, 72, 7-8; 609-633
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Maldi – metoda do zastosowań w analizie strukturalnej polimerów
    Maldi – method for use in structural analysis of polymers
    Autorzy:
    Swinarew, B.
    Swinarew, A. S.
    Powiązania:
    https://bibliotekanauki.pl/articles/171598.pdf
    Data publikacji:
    2014
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    polimery
    spektrometria mas z jonizacją laserową wspomaganą matrycą
    MALDI-TOF
    kopolimery
    degradacja polimeru
    polymers
    matrix-assisted laser desorption ionization mass spectrometry
    MALDI-TOF MS
    copolymers
    polymer degradation
    Opis:
    Polymers as one of the fastest growing groups of widespread use of synthetic materials are characterized by a great diversity of structures. Structural characterization of polymers generally includes: an assessment of the average molecular weight (Mn) and the molar mass distribution (PD) to determine the structure of repeating units (mers) sequence analysis of the copolymer, identification of the end groups, the detection and identification of contaminants and substances present in the composition of the polymer asa dopant. Modern mass spectrometry (MS) offers the opportunity to study the smallest structural details of macromolecular materials [1–10]. Because of the variety of potential structures of polymer analysis process is to answer a few questions by a certain pattern. The first step is to determine the chemical structure of the polymer backbone. The second step is to identify whether the chains have branching points and define the degree of branching. The third important step is to correct end groups identification, also for the detection of cyclic oligomers that can be present. The structural studies can be made by mass spectrometer using reflectron mode. In the essence, the method involves three steps. The first analysis is performed with standard mass spectrum of the sample. Then the precursor ion (parent ion) is selected, which is subjected to further analysis by MS changed voltages and reflectron mode. This paper aims to present the issues related to the detailed analysis and characterization of polymeric materials produced on a large scale. Before, for materials such as poly(propylene), poly(ethylene), poly(styrene), polycarbonate, etc., increasing demands on the mechanical and technological parameters were placed. Maintaining a high level of products is associated with a very rigorous process control of the manufacturing, processing and transportation at every stage. The optimal tool for the structural characteristics of these polymeric materials is the defense technique MALDI-TOF MS (Matrix-Assisted Laser Desorption/Ionization Time- -Of-Flight Mass Spectrometer) due to its versatility, speed and extremely high precision. Below, we present some aspects of MALDI MS analysis of polymeric materials and composites. Note, that the following literature review focuses on the recent developments in the field of preparation of the samples, to achieve high mass resolution, the identification of polymers and copolymers, the accuracy of the molar mass determination and the identification of functional end groups, sequence analysis of the copolymer.
    Źródło:
    Wiadomości Chemiczne; 2014, 68, 7-8; 645-660
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Zastosowanie nanocząstek srebra w laserowej spektrometrii mas oraz w obrazowaniu MS : przegląd
    Application of silver nanostructures in laser desorption/ionization mass spectrometry and mass spectrometry imaging
    Autorzy:
    Sekuła, J.
    Nizioł, J.
    Ruman, T.
    Powiązania:
    https://bibliotekanauki.pl/articles/172137.pdf
    Data publikacji:
    2016
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    związki niskocząsteczkowe
    spektrometria mas
    obrazowanie spektrometrią mas
    matryca
    układy bezmatrycowe
    nanocząstki srebra
    low molecular weight compounds
    mass spectrometry
    mass spectrometry imaging
    matrices
    matrix free-system
    silver nanoparticles
    Opis:
    Metallic nanoparticles, especially silver nanoparticles, have attracted much attention due to their unique physical, chemical and opto-electronic properties. Silver nanoparticles have been successfully applied as a matrix replacement for the laser desorption/ionization time-of-flight mass spectrometry (LDI-ToF-MS). Silver nanoparticles (AgNPs) can efficiently absorb ultraviolet laser radiation, transfer energy to the analyte and promote analyte desorption, but also constitute a source of silver ions suitable for analyte cationisation. Nanoparticles, producing spectra with highly reduced chemical background in the low m/z region, are perfectly suited for low-molecular weight compound analysis and imaging. AgNPs have been demonstrated to allow efficient capture of different chemical compounds (including amino acids, cholesterol, fatty acids) on their surface, thus efficiently promoting their desorption and gas phase cationisation. The minimum detectable amount for those organic and biological molecules is often in the fmol range [23]. Despite the fact that scientists have developed a variety of methods for the synthesis of silver nanoparticles, there are still problems with obtaining surfaces with nanoparticles of high durability and chemical purity. Recently, a successful application of cationic silver nanoparticles (AgNPs), which were placed on MALDI targets for highly sensitive detection of d-ribose at attomolar levels as well as analysis of biological samples such as urine and blood serum [51] was shown. The application of new 109AgNPET surface has been presented with examples of analysis of nucleosides and nucleic bases [60]. One of the main directions of development of LDI-MS is the imaging mass spectrometry (MSI), enabling the visualization of surface distribution of biological samples. The critical limitations of the spatial resolution of MALDI-MSI are the size of the organic matrix crystals and the analyte migration during the matrix application process. To overcome these problems, researchers tried to use nanoparticles as substitutes of organic matrices. In 2013 Ruman group presented that direct contact of the analysed object with Ag nanoparticle-covered target permits direct surface transfer of chemical compounds. The active surface becomes then a “chemical photograph” of an object and allows MS analysis and MS imaging [68].
    Źródło:
    Wiadomości Chemiczne; 2016, 70, 7-8; 519-539
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-5 z 5

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