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Comparison of headspace solvent microextraction, hydrodistillation solvent microextraction, and solid-phase microextraction for the study of volatile components of Kelussia odoratissima Mozaff. by GC-MS

Hashemi P., Yarahmadi A, Shamizadeh M, Khademi K

Acta Chromatographica

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2012

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Vol. 24, no. 1

97--109

EN

Kelussia odoratissima Mozaff. is a wild and endangered endemic plant found only in limited areas of central Zagros mountains, Iran. Three microextraction methods, that is, headspace solvent microextraction (HS-SME), hydrodistillation solvent microextraction (HD-SME), and solid-phase microextraction (SPME), and a conventional hydrodistillation method were used and compared for the extraction and gas chromatography- mass spectrometric (GC-MS) analysis of volatile components of the plant. In the HS-SME and HD-SME methods, a suspended n-heptadecane microdroplet was used for the extraction from the sample headspace, while in the SPME method, a PDMS fiber was applied. The highest extraction efficiency was obtained for the SPME method, with the highest number of identified components and best precision. As a consequence, the SPME method was used for the comparison of the volatile components of seeds, leaves, and pedicles of K. odoratissima collected from three different regions. One of the major components of the plant was butyl phthalide. The levels of this compound in the extractions from leaves, pedicles, and seeds were 34.1, 23.8, and 12.9%, respectively. The results also showed considerable variation between the volatile components of the samples collected from different areas.

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Headspace-solvent microextraction for identification of volatile components of Myrtus communis L.

Hashemi P., Abolghasemi M. M., Ahmadi S., Ghiasvant A. R.

Acta Chromatographica

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2009

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Vol. 21, no. 1

139-149

EN

Headspace-solvent microextraction (HS-SME) and hydrodistillation coupled with GC-MS have been used for isolation and identification of the volatile components that characterize Myrtus communis L. aroma. In the HS-SME method a suspended micro-drop of n -butanol was used as solvent. The effect of six different parameters on extraction efficiency, including sample weight, drop volume, extraction temperature, conditioning time, extraction time, and ionic strength were optimized using a simplex optimization method. The volatile components were studied both by HS-SME and an ordinary hydrodistillation method and the major components identified were 1,8-cineol, #945-pinene, limonene, and linalool.

3

Headspace solvent microextraction of trace amounts of BTX from water samples

Arab J., Yamini Y., Hosseini M. H., Shamsipur M.

Chemia Analityczna

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2004

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Vol. 49, No. 1

129-137

EN

Headspace solvent microextraction (HSME) is an excellent preconcentration method for the analysis of BTX (benzene, toluene, p-xylene and o-xylene) in aqueous matrices by gas chromatography (GC). A droplet of benzyl alcohol containing methylcyclohexane as an internal standard was used for extraction. Analytes were extracted by suspending a 3 žL droplet directly from a microsyringe tip over the surface of the solution placed in a sealed vial. After extraction, the droplet was retracted back into the syringe and injected directly into a GC injection port. Experimental conditions have been optimised and their influence on the analyte peak-to-internal standard peak ratio have been studied. The linear range and the precision of the method were examined.

PL

Rozpuszczalnikowa mikroekstrakcja z fazy nadpowierzchniowej jest doskonalą metodą zatężania benzenu, toluenu, p- i oksylenu (BTX) z wodnych próbek do oznaczeń metodą chromatografii gazowej. Do ekstrakcji stosowano 3 uL kroplę alkoholu benzylowego zawierającego metylocylkoheksan jako wewnętrzny standard. Kropla była zawieszona na końcu mikrostrzykawki umieszczonej nad powierzchnią roztworu w zamkniętej ampułce. Po zakończonej ekstrakcji kropią cofano do strzykawki, a następnie wstrzykiwano wprost do chromatografu gazowego. Optymalizowano warunki doświadczalne i określono ich wpływ na stosunek piku analitu do piku wewnętrznego standardu. Zbadano zakres liniowości i precyzję metody.