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1

Capillary column coated with geminal ionic liquids as stationary phases for gas chromatographic separation

Jiang R., Yang S., Luo A.

Acta Chromatographica

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2017

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Vol. 29, no. 1

25--43

EN

Four geminal ionic liquids (GILs), namely, 1,4-bis(1,1′-butyl-3,3′- methylene- imidazolium)-benzene bis[(trifluoromethyl)sulfonyl]imide (BBMIB-NTf2), 1,4- bis(1,1′-butyl-3,3′-methylene-imidazolium)-benzene tetrafluoroborate (BBMIB-BF4), 1,4- bis(1,1′-butyl-3,3′-methylene-imidazolium)-benzene hexafluophosphate (BBMIB-PF6), and 1,4-bis(1,1′-methyl-3,3′-methylene-imidazolium)-benzene bis[(trifluoromethyl) sulfonyl] imide (BMMIB-NTf2), were synthesized. They were statically coated onto the inner walls of fused-silica capillary columns and used as stationary phases for gas chromatography. The evaluation of BBMIB-NTf2, BBMIB-BF4, BBMIB-PF6, and BMMIB-NTf2 as stationary phases is reported here for the first time. These new stationary phases exhibit efficiencies of at least 2.3 × 103 plates per meter. Abraham solvation parameter model was used to evaluate the solvation characteristics. The system constants indicated that the dipolarity/polarizability and the hydrogen-bond basicity play a major role among five molecular interactions between stationary phases and solute molecules. A fundamental understanding into the solvation characteristics of these GILs can be used as a guide to choosing the appropriate geminal ionic liquids for specific applications in various fields. The chromatographic separation performance was evaluated by a Grob test mixture, n-alkanes, alcohols, and aromatic isomers. Furthermore, the thermal stability was tested. The present results demonstrate that these geminal ionic liquids stationary phases possess excellent chromatographic separation performance and good thermal stability (at least up to 270 °C) and may be applicable as gas chromatography stationary phases for more application.

2

Evaluation of a CGC-FID method for qualitative and quantitative analysis of azole antifungal drugs

Ekiert R. J., Krzek J., Czekaj J. S., Hubicka U.

Acta Chromatographica

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2009

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Vol. 21, no. 2

273--282

EN

This paper presents a new method for identification and quantitative analysis of six azole antifungal drugs — bifonazole, clotrimazole, econazole, fluconazole, ketoconazole, and miconazole — by capillary gas chromatography (CGC) combined with flame ionization detection (FID). The chromatographic separation conditions were established and the method was validated for precision (RSD = 1.49–3.55%), recovery (98.6–101.2%), and linearity within the range under investigation (∼1.0–33.3 ng). The results obtained show the newly developed procedure is suitable for qualitative and quantitative pharmaceutical analysis of the six azoles.

3

GC separation of enantiomers of secondary alcohols and n-pentyl secondary alkyl ethers on modified beta- and gamma-cyklodextrin stationary phases

Krupčik J., Benická E., Špánik I., Májek P., Birasová H., Sandra P., Armstrong D. W.

Chemia Analityczna

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2004

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Vol. 49, No. 6

895-904

EN

Gas chromatographic separation of enantiomers of C4 - C8 secondary alcohols and n-pentyl secondary alkyl ethers has been studied using capillary columns with the following stationary phases: heptakis(6-O-tert-butyldimethylsilyl-2,3-di-O-acetyl)- ß-cyclodextrin (6-TBDMS-2,3-DA- ß-CD), permethyl- ß-cyclodextrin (ChirasilDex), heptakis-(2,6-di-Omethyl-3-O-pentyl)- ß-cyclodextrin (2,6-diMe-3-Pe- ß-CD), and octakis-(2,6-di-O-methyl-3-O-pentyl)- gamma-cyclodextrin (2,6-diMe-3-Pe-gamma-CD). On the 6-TBDMS-2,3-DA-ß-CD support enantiomers of secondary alcohols were successfully separated, contrary to n-pentyl secondary alkyl ethers. In turn, the latter were successfully separated on 2,6-diMe-3-Pe-ß-CD and 2,6-diMe-3-Pe-gamma-CD columns, oppositely to the corresponding secondary alcohols. Different enantioselectivities of polar and non-polar cyclodextrin stationary phases were discussed in the light of various contributions of polar and non-polar interactions to the separation phenomena.

PL

Za pomocą chromatografii gazowej badano rozdzielanie enanciomerów drugorzędowych alkoholi C(4)-C(8) i drugorzędowych n-penly!owych eterów alkilowych przy użyciu kolumn kapilarnych, w których fazami stacjonarnymi były: heptakis(6-O-tert-butyodimetyosililo,3-di-O-acety1o)-Beta-cyklodekstryna(6-TBDMS-2,3-DA-Deta-CD), permetyIo-Beta-cyklodeks-tryna (Chirasil Dex), heptakis-(2,6-di-O-metylo-3-O-pentylo)-/Gamma-cyklodekstryna (2,6-di Me-3-Beta--CD) i oktakis-(2.6-di-O-metylo-3-O-pentylo)-y-cyklodekstryna (2,6-di Mc-3-Pe-^CD). Stwierdzono, że enancjomery alkoholi drugorzędowych rozdzielały się dobrze przy użyciu kolumny z ć-TBDMS-2,3-DA-Beta-CD, natomiast drugorzędowe n-pentyiowe etery alkilowe nie rozdzielały się przy użyciu tej kolumny. Enancjomery eterów rozdzielały SIĘ dobrze przy użyciu kolumn z 2,6-di Me-3-Pe-Beta-CD i 2,6-di Me-3-Pe-yCD, przy użyciu tych kolumn nie rozdzielały się jednak drugorzędowe alkohole. Różną enancjoselektywność polarnych i niepolamych cyklodekstrynowych faz stacjonarnych tłumaczy się między innymi różnymi oddziaływaniami o charakterze polarnym i niepolarnym.

4

Organic geochemistry of the Grodziec beds (Upper Carboniferous) : Upper Silesian Coal Basin, Poland

Bzowska G., Fabiańska M., Matuszewska A., Racka M., Skręt U.

Geological Quarterly

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2000

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Vol. 44, Nr 4

425-437

EN

Five lithologically different rock samples from the "Niwka" brickyard exposure, including one coal sample, were geochemically characterized as regards their mineral composition and sedimentary organic matter present in them. Various methods, including: X-ray diffraction, solvent extraction, group separation by preparative thin layer chromatography, infra-red spectroscopy for assessment of the content of different functional groups in total rock extracts and their separated polar compound fractions, and capillary gas chromatography for analysis of aliphatic hydrocarbon fractions. It was found that the "Niwka" brickyard rocks are rich in organic material present as the plant detritus (cane-break) or as compounds adsorbed on clay and carbonaceous minerals. Yields of bitumen extraction, group composition of extracts and content of various functional groups assessed by infra-red spectra seem to be related to mineral composition of the host rocks and type of kerogen present. Higher contents of clay minerals, especially chlorite, enriches both extracts and their polar compound fractions in aliphatic structures while the organic matter of both sandstones analysed contains more condensed aromatic structures and functional oxygen groups. Generally the organic matter of the host rocks was deposited in an oxic environment and belongs to type III kerogen with a dominant terrestrial biogenic source or to type II kerogen of bacterial/terrestrial origin of primary biogenic matter. Its thermal maturity stage can be estimated as end-diagenetic or early catagenetic. The highest maturity is shown by the organic matter in the basal sandstone (the S2 sandstone) and probably is caused by imput of older migrating bitumen. Biodegradation of organic matter seems to be influenced by the mineral composition of the host rock, with a high content of clay minerals giving protection.

5

Determination of Alphacypermethrin in the Air by Capillary Gas Chromatography

Pomorska K.

International Journal of Occupational Safety and Ergonomics

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1999

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Vol. 5, No. 4

529--536

EN

A new method for sampling and chemical analysis of alphacypermethrin in workplace air has been described. Air samples were taken using a glass tube filled with silica gel with chemically bounded octadecyl phase. Chromatographic determinations were conducted using an HP-5 capillary column (10 m x 0.53 mm) and an electron-capture detector. Alphacypermethrin recovery was 100.15%. The calculated detection limit for a 60-L air sample was 0.0001 mg/m3.