Dynamic electromembrane extraction #briefpost

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The potential of electromembrane extraction (EME) is beyond any doubt [1]. As you well know, it is based on the electromigration of the target charged analyte from the donor phase (the sample) to the aqueous acceptor phase through a polymeric membrane that physically separates both phases. The extraction is rapid and it provides high enrichment factors.

In its conventional format, EME is developed in static mode. What would happen if the sample and even the acceptor phase are dynamically introduced in the extraction device? This question has been recently answered in an article published in Journal of Chromatography A [2].

Our colleagues have designed an extraction device where the sample and the acceptor phase can flow dynamically thanks to a peristaltic and a syringe pump, respectively. This configuration permits to process a larger sample volume (increasing the enrichment factor) without modifying the diffusion distance sample/acceptor phase. In fact, the flow of the sample increases the analytical signals two times while a similar effect is observed for the movement of the acceptor phase.

The method has been applied for the determination of amitriptyline and nortriptyline in plasma and urine samples. Limits of detection lower than 1 mg/L are reported using HPLC-UV as instrumental technique.

You will find the device description and optimization in the original article.

References
[1] Electromembrane extraction of biological samples: determining stimulant drugs in whole blood. Link to the post

[2] Dynamic electromembrane extraction: Automated movement of donor and acceptor phases to improve extraction efficiency. Link to the article

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