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    Tytuł:
    Adsorbenty ze związanymi cieczami jonowymi i ich wykorzystanie w przygotowaniu próbek oligonukleotydów
    Adsorbents with bonded ionic liquids and their use in the preparation of oligonucleotides samples
    Autorzy:
    Nuckowski, Łukasz
    Zalesińska, Ewa
    Studzińska, Sylwia
    Powiązania:
    https://bibliotekanauki.pl/articles/172150.pdf
    Data publikacji:
    2020
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    przygotowanie próbek
    oligonukleotydy
    ciecze jonowe
    adsorbenty
    sample preparation
    oligonucleotides
    ionic liquids
    adsorbents
    Opis:
    Oligonucleotides are short fragments of nucleic acids. They have a growing potential in medicine, especially as diagnostic and therapeutic agents. In most cases, these compounds are determined in the complex biological matrix. Thus, the sample preparation step is very important in their bioanalysis. Solid-phase extraction is a predominant technique in this field. However, presently used for this purpose adsorbents have disadvantages. They ensure low extraction effectiveness and procedures using them are labor-intensive or time-consuming. Ionic liquids, since their discovery, are objects of intensive interest of scientists. Their scientific attractiveness is connected with their unique properties. They are used in separation and sample preparation techniques, such as liquid-liquid extraction using water-immiscible ionic liquids. This approach was also used in the extraction of oligonucleotides. Adsorbents modified with ionic-liquids have growing potential in extraction techniques. Few types of materials are used, namely carbon, polymers, and silica. A common feature of these materials modified with ionic liquids is the ion exchange character. Nonetheless, carbon nanomaterials are coated or covalently modified with ionic liquids, and they are used mainly for nonpolar compounds. Polymer and silica-based adsorbents are used mainly for acidic compounds. Polymers are characterized by the highest stability of the presented materials. Due to their ion-exchange properties crosslinked poly(ionic liquids) were used also for extraction of unmodified and modified oligonucleotides. The optimized procedure applying the material with bonded zwitterion ionic liquid gives high recoveries. It is concurrent for presently used adsorbents, thus solves problems connected with their usage. Moreover, it can be used for biological samples without any pre-purification.
    Źródło:
    Wiadomości Chemiczne; 2020, 74, 7-8; 545-565
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Chromatograficzna analiza związków budujących kwasy nukleinowe
    Chromatographic analysis of nucleic acids constituents
    Autorzy:
    Studzińska, S.
    Rola, R.
    Łobodziński, F.
    Krzemińska, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/172180.pdf
    Data publikacji:
    2016
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    nukleozydy
    nukleotydy
    oligonukleotydy
    chromatografia cieczowa
    czułość
    selektywność
    nucleosides
    nucleotides
    oligonucleotides
    liquid chromatography
    sensitivity
    selectivity
    Opis:
    Understanding the characteristics, role and structure of nucleic acids allowed to answer questions about the disease processes. Today, nucleic acids and their constituents are tools, which are used by molecular biology in medicine and biotechnology. Antisense and gene therapy are intensively developing methods for possible treating or preventing disease. They use short fragments of DNA or RNA - oligonucleotides to silence the genes expression. They are not the only ones that allow analytical chemists to obtain information about the state of our body. Determination of modified nucleoside allows detection of cancer, while analysis of nucleotides allows the estimation of strengthening the immune system. There is a great need of sensitive, selective and precise methods of separation of nucleosides, nucleotides and oligonucleotides and their qualitative and quantitative analysis. Consequently liquid chromatography (LC) is the most commonly used for analysis of nucleic acid constituents. The most widely used modes of LC include Ion Exchange Chromatography (IEC) and Reversed Phase High Performance Liquid Chromatography (RP HPLC). Both techniques have their advantages and disadvantages in the analysis of nucleosides, nucleotides and oligonucleotides. In the case of IEC it is necessary to use high concentrations of the salt in the mobile phase or concentration gradients, which considerably limits the possibility of using MS detection. RP HPLC can be coupled with MS detection but only when volatile salts are mobile phase components. On the other hand there is a significant problem is the lack of sufficient selectivity for the most polar nucleosides and nucleotides. RP HPLC MS is still most often used in the determination of nucleosides and nucleotides, due to its high sensitivity and a comprehensive qualitative analysis. Another system used for the HPLC analysis of oligonucleotides is Ion Pair Reversed Phase High Performance Liquid Chromatography (IP RP HPLC). These compounds can not be analyzed by RP HPLC due to their high polarity. The advantage of IP RP HPLC is selectivity, achieved by a suitable choice of mobile phase composition and the possibility of using MS. A disadvantage of IP RP HPLC in the analysis of oligonucleotides is however lower sensitivity compared to RP HPLC. During the last few years Hydrophilic Interaction Liquid Chromatography (HILIC) was applied for the separation of mixtures of nucleosides, nucleotides, oligonucleotides extracted from a biological or food samples. The presented results demonstrate the usefulness of this method, however, the resolving power is limited due to the asymmetric peak shape. On the other hand proper selection of the mobile and stationary phase can lead to a high selectivity in the analysis of the most polar nucleosides, nucleotides and oligonucleotides, which can not be separated by RP HPLC.
    Źródło:
    Wiadomości Chemiczne; 2016, 70, 9-10; 633-656
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Synteza modyfikowanych oligonukleotydów zawierających stereozdefiniowane internukleotydowe wiązania tiofosforanowe
    Synthesis of modified oligonucleotides containing stereodefined internucleotide phosphorothioate bonds
    Autorzy:
    Radzikowska, E.
    Kaczmarek, R.
    Baraniak, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/172219.pdf
    Data publikacji:
    2015
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    oligonukleozydotiofosforany
    oligonukleotydy antysensowe
    synteza modyfikowanych oligonukleotydów
    synteza stereospecyficzna
    oligo(deoxy)ribonucleoside phosphorothioates
    antisense oligonucleotides
    synthesis of modified oligonucleotide
    stereospecific synthesis
    Opis:
    Synthetic oligonucleotides constitute an important class of compounds which can exhibit biological activity. As potential drugs they could be employed in antisense strategy by acting on the pathogenic mRNA, causing inactivation of the target molecules during the translation process [1]. Ideal antisense agent (ASO) should be resistant to exo and/or endonucleases, exhibit a suitable pharmacological and pharmacokinetic profile and exhibits high binding affinity towards the target mRNA. To improve some properties of the ASO plethora of the chemical modifications introduced within the nucleobase, sugar unit and internucleotide linkage are investigated [3]. Among them, phosphorothioate oligonucleotides (PS-oligo), created by replacing one of the nonbridging oxygen atoms with a sulfur atom, are the major representatives of DNA analogs. PS-oligo display several attractive features like nuclease resistance, activation of RNase H, and good pharmacokinetic properties [1]. Replacement of one of two nonbridging oxygens at phosphorus by sulfur induces asymmetry at the phosphorus atom. Hence, the synthesized oligo(nucleoside phosphorothioate) is a mixture of 2n diastereomers (where n is the number of internucleotide phosphorothioate functions). Therefore the actual biological activity of the P-chiral oligonucleotide analogues, (e.g., interactions with proteins or nucleic acids) may depend on stereochemical factors [7]. One has to keep in mind that the phosphoramidite [5] and H-phosphonate [32] methodologies (commonly used to prepare PS-oligo) are nonstereospecific and give a mixture of 2n diastereomers. Thus, various methods have been elaborated to synthesize these P-chiral oligonucleotide analogs in a stereocontrolled manner [15, 17], among them the oxathiaphospholane method developed by Stec et al. [18], the method utilizing nucleoside 3’-O-(3-N-acyl)oxazaphospholidine derivatives as monomer units [19], and the method based on a stereoselective synthesis of nucleoside 3’-O-oxazaphospholidine monomers [21, 22] are the most significant.
    Źródło:
    Wiadomości Chemiczne; 2015, 69, 11-12; 957-981
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Zastosowania „click chemistry” w modyfikacjach nukleozydów i oligonukleotydów
    Applications of click chemistry in modification of nucleosides and oligonucleotides
    Autorzy:
    Gładysz, M.
    Milecki, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/171589.pdf
    Data publikacji:
    2014
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    click chemistry
    CuAAC
    modyfikacje nukleozydów
    oligonukleotydy
    DNA
    kwas deoksyrybonukleinowy
    RNA
    kwas rybonukleinowy
    Click Chemistry
    nucleosides modifications
    oligonucleotides
    deoxyribonucleic acid
    ribonucleic acid
    Opis:
    Since the year 2001 new ideology of clean and simple synthesis in organic chemistry has been established. The outstanding scientists Meldal and Sharpless presented their concepts of Click Chemistry. Among the reactions chosen for this concept the reaction of Copper(I) Catalyzed Alkyne-Azide Cycloaddition (CuAAC) became the most popular one. It is the basis of syntheses employed for building blocks synthesis in medicinal chemistry and material science. Libraries of potentially pharmacologically active anticancer and antivirus compounds possessing neutral triazol linkage could be easily obtained. Remarkable efficiency of CuAAC reaction influenced on DNA- and RNAbased synthesis of novel oligonucleotides derivatives. Many of nucleic acid molecular modifications found applications in enzymatic transformation, nucleic acid hybridization, molecular tagging and gene silencing. The CuAAC reaction allows for introducing modifications into practically every region of nucleoside/nucleotide/ oligonucleotide. This includes versatile modifications of the base moiety both aiming at the base pairing ability or specific labeling of the nucleoside unit. Different conjugates (bio-, fluorescent-, affinity- or spin labels) are being attached to the base part of the nucleic acid taking advantage of the presence of azide or alkyne substituents, which can be installed without great difficulty. Labeling at the sugar part of the nucleoside can be realized at the position 2’, 3’ or 5’, the latter two giving rise to the end-labeled oligonucleotides and the 2’ position serving as the attachment point for labeling inside the oligonucleotide chain. These kind of nucleic acid modifications are very promising. Versatility of CuAAC reactions is demonstrated by numerous examples of introducing modifications into practically every reactive site of the nucleotide/oligonucleotide molecule. The review systematically presents application of the “click” technique for modification of nitrogenous base, sugar or pseudosugar moiety or phosphorus center. Possibility of creating new kind of chain linkage, devoid of negative charge and nuclease resistant is also shown. This allows to design a new class of nucleic acid analogues, similar in its DNA-mimicking properties to PNA’s.
    Źródło:
    Wiadomości Chemiczne; 2014, 68, 7-8; 617-643
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Zastosowanie cieczy jonowych jako modyfikatorów fazy ruchomej w chromatografii cieczowej
    Application of ionic liquids as mobile phase modifiers in liquid chromatorgaphy
    Autorzy:
    Kilanowska, Anna
    Zielak, Judyta
    Studzińska, Sylwia
    Powiązania:
    https://bibliotekanauki.pl/articles/172012.pdf
    Data publikacji:
    2020
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    ciecze jonowe
    chromatografia cieczowa
    blokowanie wolnych silanoli
    chromatografia par jonowych
    oligonukleotydy antysensowne
    ionic liquids
    liquid chromatography
    free silanol suppressors
    ion pair chromatography
    antisense oligonucleotides
    Opis:
    Ionic liquids are molten salts composed of large, asymmetric, organic cations (e.g. imidazolium or piperidine) and inorganic anions such as e.g chloride or fluoroborate. These compounds are characterized by low melting point, below 1000C, however, they also have other interesting properties including high thermal stability, minor vapor pressure or negligible volatility. Moreover, by the appropriate selection of the cation and anion building the ionic liquid, it is possible to obtain the desired physicochemical properties of these salts. For this reason, ionic liquids are applied to the synthesis, catalysis, electrochemical methods, extraction methods, etc. Application of these compounds in separation techniques merits special attention, especially considering liquid chromatography. Ionic liquids are commonly used in this technique as free silanols suppressors, especially regarding the analysis of basic compounds. Moreover, the excess amount of ionic liquids ions may adsorb on the hydrophobic ligands present at the stationary phase surface, which also plays a significant role in the retention of analytes. Besides their application as silanols suppressors, these compounds were also used as ion pair reagents in the analysis of antisense oligonucleotides, which are short nucleic acid fragments with therapeutic potential due to the ability to bind with complementary sequences of ribonucleic acid. For this reason, antisense oligonucleotides are used in the treatment of several diseases. This article briefly presents structures, properties and the application of ionic liquids as mobile phase modifiers for the analysis of the wide range of different analytes using liquid chromatography. Moreover, a part of this paper was devoted to the analysis of antisense oligonucleotides with the use of the different chromatographic techniques, including the application of ionic liquids as mobile phase additives in ion pair chromatography.
    Źródło:
    Wiadomości Chemiczne; 2020, 74, 7-8; 507-525
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-5 z 5

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