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Liquid phase microextraction techniques combined with chromatography analysis: a review

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Dugheri S. , Mucci N. , Bonari A. , Campagna M. , Montalti M. , Arcangeli G. , Ubiali D. , Marrubini G. , Cappelli G.

Acta Chromatographica

2020

tom Vol. 32, no. 2

69--79

Sample pretreatment is the first and the most important step of an analytical procedure. In routine analysis, liquid–liquid microextraction (LLE) is the most widely used sample pre-treatment technique, whose goal is to isolate the target analytes, provide enrichment, with cleanup to lower the chemical noise, and enhance the signal. The use of extensive volumes of hazardous organic solvents and production of large amounts of waste make LLE procedures unsuitable for modern, highly automated laboratories, expensive, and environmentally unfriendly. In the past two decades, liquid-phase microextraction (LPME) was introduced to overcome these drawbacks. Thanks to the need of only a few microliters of extraction solvent, LPME techniques have been widely adopted by the scientific community. The aim of this review is to report on the state-of-the-art LPME techniques used in gas and liquid chromatography. Attention was paid to the classification of the LPME operating modes, to the historical contextualization of LPME applications, and to the advantages of microextraction in methods respecting the value of green analytical chemistry. Technical aspects such as description of methodology selected in method development for routine use, specific variants of LPME developed for complex matrices, derivatization, and enrichment techniques are also discussed.

Solid phase microextraction techniques used for gas chromatography: a review

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Dugheri S. , Mucci N. , Bonari A. , Marrubini G. , Cappelli G. , Ubiali D. , Campagna M. , Montalti M. , Arcangeli G.

tom Vol. 32, no. 1

1--9

In the last decade, the development and adoption of greener and sustainable microextraction techniques have been proved to be an effective alternative to classical sample preparation procedures. In this review, 10 commercially available solid-phase microextraction systems are presented, with special attention to the appraisal of their analytical, bioanalytical, and environmental engineering. This review provides an overview of the challenges and achievements in the application of fully automated miniaturized sample preparation methods in analytical laboratories. Both theoretical and practical aspects of these environment-friendly preparation approaches are discussed. The application of chemometrics in method development is also discussed. We are convinced that green analytical chemistry will be really useful in the years ahead. The application of cheap, fast, automated, “clever”, and environmentally safe procedures to environmental, clinical, and food analysis will improve significantly the quality of the analytical data.

Fast gas chromatography of polar and non-polar compounds with the on-column injection

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Dömötörova M. , Matisowa E. , Hrouzkova S. , Hercegova A.

Chemia Analityczna

2005

tom Vol. 50, No. 2

365-375

Fast gas chromatography (GC) with the on-column injection of large volumes of polar compounds of a broad range of volatility (in the range of volatilities ofrt-alkanes C16-C26) has been performed. The GC system comprised a normal-bore retention gap (1 m x 0.32 mm I.D. and/or 0.53 mm I.D.) coupled with a narrow-bore analytical column (5 m x 0.1 mm I.D. x 0.4 [am film thickness, HP-1 MS) using a standard glass press-fit connector. The effect of the injection volume, pre-column I.D. and polarity, and solvent polarity and volatility on the peak width and shape, as well as on the focusing of polar pesticides and n-alkanes has been discussed. The precision of chromatographic measurements with hydrogen as the carrier gas under the constant inlet pressure and fast temperature programming for fast separations of large volume injections (1-8 μL) was found to be good. For polar pesticides the occurrence of adsorption phenomena was evidenced. They were dependent on the quality of the pre-column.

Za pomocą szybkiej chromatografii gazowej, stosując bezpośrednie dozowanie do kolumny dużych objętości, chromatografowano związki polarne różniące się znacznie lotnością (w zakresie lotności n-alkenów C16-C26). W chromatografie zastosowano przedkolumnę, I m x 0,32 mm i/lub 0.53 mm, połączoną z kolumną analityczną 5 m x O, l mm x 0.4 μm; HP-1 MS. Przedyskutowano wpływ objętości zadozowanej próbki, średnicy i polarności przed kolumny oraz lotności i polarności rozpuszczalnika na szerokość i kształt piku oraz na szerokość pasm polarnych pestycydów i n-alkenów. Stwierdzono, że precyzja pomiarów chromatograficznych przy zastosowaniu wodoru jako gazu nośnego, stałego ciśnienia na wlocie oraz szybkiego programowania temperatury do szybkiego rozdzielania dużych objętości (1-8 1-8 μL) była dobra. W przypadku polarnych pestycydów wystąpiły zjawiska adsorpcyjne. Były one zależne od jakości przedkolumny.