Wyniki wyszukiwania - BazTech

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Zastosowanie cieczy jonowych jako modyfikatorów fazy ruchomej w chromatografii cieczowej

Kilanowska Anna, Zielak Judyta, Studzińska Sylwia

Wiadomości Chemiczne

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2020

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[Z] 74, 7-8

507--525

EN

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.

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Analiza oligonukleotydów antysensownych pierwszej i drugiej generacji za pomocą chromatografii par jonowych

Kaczmarkiewicz Anna, Nuckowski Łukasz, Studzińska Sylwia, Buszewski Bogusław

Analityka : nauka i praktyka

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2019

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nr 2

4--11

PL

Rosnące zainteresowanie badaczy potencjalnymi terapeutykami, jakimi są oligonukleotydy antysensowne, sprawia, że wymagana jest ich czuła analiza na różnych etapach badań klinicznych.

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Determination of sulfite by ion pair chromatography using pre-column derivatization with iron(III)-1,10-phenanthroline complex

Janovskiene G., Paliulionyte V., Padarauskas A.

Chemia Analityczna

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2002

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Vol. 47, No. 6

847-854

EN

An ion-pair chromatographic (IP-HPLC) method was developed for the selective and sensitive determination of sulfite. The proposed method is based on the pre-column derivatiza-tion of sulfite with iron(III)-l,10-phenathroline complex (Fe(phen)(3+/(3) and direct photometric detection of Fe(phen)(2+)(3) formed. The optimized separations were carried out on a C(18) column using acetonitrile-water (60:40) mobile phase containing 50 mmol L(-1) NaClO4 and 5 mmol L(-1) acetate buffer (pH 5.0) and direct photometric detection at 510 nm. The optimal conditions for the derivatization reaction were established by varying pH, concentration of Fe(phen)(3+)/3 and reaction temperature. Valid calibration (r2 = 0.998) is demonstrated in the range 2 x 10(-6)-5 x 10(-4) mol L(-4) of sulfite. The detection limit (S/N = 3) was 5 x 10(-7) mol L(-1). The proposed system was applied to the determination of free sulfite in wines. The recovery tests established for wine samples were within the range 94-105%. The IP-HPLC results agree with those obtained by iodometric titration technique.

PL

Opracowano selektywną i czułą metodę oznaczania siarczynów przy pomocy chromatografii par jonowych (IP-HPLC). Proponowana metoda jest oparta na przedkolumnowej derywaty-zacji siarczynu przy użyciu kompleksu żelazo(III)-1, 10-fenantrolina Fe(phen)(+3/3 Utworzony jon Fe(phen)j+jest bezpośrednio mierzony fotometrycznie przy długości fali 510 nm. Optymalizację rozdziału przeprowadzono na kolumnie C(18) z fazą ruchomą acetonitryl-woda (60:40) z dodatkiem 50 mmol L(-1) NaClO(4) i 5 mmol L(-1) buforu octanowgo (pH 5,0). Optymalne warunki reakcji derywatyzacji ustalano zmieniając wartości pH, stężenie Fe(phen)(+3)/(3) oraz temperaturę. Liniową zależność kalibracyjną (r2 = 0,998) uzyskano w zakresie stężeń 2 x 10(-6) -5 x 10(-4) mol L(-1) siarczynów. Granica wykrywalności (S/N = 3).