Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "cząsteczka" wg kryterium: Temat

  Lista filtrów
Wyrównaj
    Wyświetlanie 1-2 z 2
    Tytuł:
    Propozycje innowacyjnych sorbentów w przygotowaniu próbek biologicznych
    Proposals of innovative sorbents in the preparation of biological samples
    Autorzy:
    Pajewska-Szmyt, Martyna
    Gadzała-Kopciuch, Renata
    Buszewski, Bogusław
    Powiązania:
    https://bibliotekanauki.pl/articles/1413237.pdf
    Data publikacji:
    2021
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    metody przygotowania próbki
    dyspersyjna ekstrakcja do fazy stałej
    próbki biologiczne
    polimery z odciśniętą cząsteczką
    sample preparation method
    dispersive solid phase extraction
    biological sample
    molecularly imprinted polymers
    Opis:
    The sample preparation stage is a critical step in the whole analytical procedure as it often determines the efficiency of the process. What is particularly noticeable in the area of biological samples. Blood, milk, urine, saliva or tissue are only few examples of complicated biological matrix, that require a optimization of sample pre-treatment method for particular analytes. For these purpose, the aim of following chapter was to characterized main problems with sample preparation method as well as highlighted some innovative ways how to improve sample preparation stage. Attention was particularly focused on the use of dispersive solid phase extraction (dSPE), which has achieved high growth in interest in recent years, mainly due to the simplicity and rapidity of performance. This method is not only used with commercially available sorbents, but also provides a basis for trying to apply new analytical tools for separation of analytes from matrix. Following the trends of nanotechnology and within the rules of green analytical chemistry, scientists are facing the challenges of determining and identifying compounds from various chemical groups. Frequently targeting analytes at trace concentration levels as well biological samples. In addition, attention is also focused on reagents reduction and shorter analysis time but also in terms of minimization of sample volume, which should to be collected. Herein the chapter presented describes exemplary new proposals in sorbents such as molecularly imprinted polymers (MIPs), supported ionic liquids (ILs), dendrimers and metal-organic framework (MOFs). In addition, it also looked at the potential use of magnetic nanoparticles as carriers. New sorbents in sample preparation together with modem instrumental techniques therefore allow the development of a procedure that will be characterized by high selectivity and specificity.
    Źródło:
    Wiadomości Chemiczne; 2021, 75, 7-8; 1075-1088
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Spektrometria mas w rozróżnianiu związków chiralnych
    Chiral recognition by mass spectrometry
    Autorzy:
    Drabik, E.
    Powiązania:
    https://bibliotekanauki.pl/articles/172040.pdf
    Data publikacji:
    2011
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    spektrometria mas
    rozróżnianie związków chiralnych
    związki chiralne
    oddziaływania typu gość-gospodarz
    metoda kinetyczna
    reakcje kompleksów jon–cząsteczka
    spektrometria ruchliwości jonów
    mass spectrometry
    chiral recognition
    kinetic method
    host–guest interaction
    ion-molecule reaction
    ion mobility spectrometry
    Opis:
    The phenomenon of optical activity was discovered by Louis Pasteur in 1848. Since this time, chirality of organic compounds observed in biological systems has became a central theme in scientific research. Synthesis and quantitation of enantiomerically pure compounds is important for a wide range of applications. Chirally pure compounds are required not only by pharmacology, but they are also of interest in cosmetic and food industry and many other applications. Similarity of enantiomers in their chemical and physical properties, except for optical rotation, makes their separation and detection very difficult. Until now, many methods have been used for the enantioselective discrimination of organic compounds, including nuclear magnetic resonance spectroscopy (NMR), circular dichroism (CD), capillary electrophoresis (CE) and chromatography (GC, HPLC), where an interference of a solvent cannot be excluded. Recent studies have shown that mass spectrometry (MS) is an alternative approach to traditional method for chiral recognition and determination of enantiomeric composition. Although, mass spectrometry has been considered as insensitive to chirality because enantiomers have the same mass and show identical mass spectra, it is now accepted as important tool for differentiating of enantiomeric compounds through their interactions with chiral reference molecules (Fig. 1). The ability to transfer diastereomeric non-covalent complexes between chiral selectors and analyte enantiomers, which differ in stability, into the gas-phase and measure such differences trough mass spectrometric ion abundances, has appeared with development of soft ionization techniques such electrospray ionization (ESI), fast atom bombardment (FAB) and matrix-assisted laser desorption/ionization (MALDI). Mass spectrometry-based methods for chiral recognition and quantitative determination of enantiomeric purity are attractive due to their speed, high sensitivity, low sample consumption, tolerance to impurities and ability to probe the analyte in a solvent free environment. Currently, there are four well-defined approaches for determining a measure of enantiomer discrimination, using either single-stage or tandem mass spectrometry. They can be classified into the following categories: (1) measurement of the relative abundance of diastereomeric complexes between chiral reference compound and the enantiomers (usually one isotopically labeled [10]), (2) enantioselective ion/molecule reaction between diastereomeric complexes and chiral or achiral reactants [11], (3) kinetic method [12] and (4) collision-induced dissociation (CID) of diastereomeric adducts in a tandem mass spectrometry (MS/MS) experiment [61, 62]. Over the past decade, new approaches to chiral separation and analysis of enantiomers have been introduced, where molecules are separated based on their mobility (ion mobility spectrometry) [66].
    Źródło:
    Wiadomości Chemiczne; 2011, 65, 7-8; 609-649
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-2 z 2

      Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies