Low cost polymeric material in sorptive microextraction

By R. Lucena -
The usefulness of sorptive microextraction approaches, like solid phase microextraction (SPME) or stir bar sorptive extraction (SBSE), in the isolation and preconcentration of organic pollutants from water is well established in the scientific literature. Classic SPME or SBSE are mainly focused on the extraction of non-polar compounds since the typical coating, polydimethlysiloxane (PDMS), is hydrophobic. While the main pollutants considered 20 years ago had a hydrophobic nature, most of the emerging contaminants present a medium to high polarity. Therefore, new sorptive phases are desirable in order to extend the scope of these extraction techniques.


In a article recently published in Analytica Chimica Acta, Prieto et al. evaluated the extraction performance of three polymeric materials, namely: polyethersulphone (PES), polypropylene (PP) and Kevlar (Kv). For this purpose 15 different analytes, covering a wide range of polarities, were evaluated as probes. In fact, the log Kow (Kow, octanol/water partition coefficient) were in the range between -0.07 and 6.88. In this research, the main variables involved in the extraction process are studied in depth for any type (polar and non-polar) of analyte. Moreover, the experimental results were also used to calculate the partition coefficient between the polymeric phase and water (Kpw) which can be useful for further applications. In this sense, PES presents the higher Kpw values compared to PDMS for almost all the analytes.

For more detailed information the readers are referred to the original article

Link to the article: Evaluation of low-cost disposable polymeric materials for sorptive extraction of organic pollutants in water

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