Critical evaluation of microextraction pretreatment techniques—Part 2: Membrane‐supported and homogenous phase based techniques

Abstract

This review follows up on Part 1, which focused on classification and evaluation of single drop and sorbent‐based microextraction techniques. Membrane‐ and homogenous phase‐based microextraction techniques are discussed and classified in Part 2. These techniques are more recent than those in Part 1 and considerable attention has been paid to their development. The new methodologies are more sensitive and, thanks to their miniaturization, they can be classified as “green”, but no exhaustive classification is available. We hope that this review will contribute to better orientation in these methods.

Isolation and quantification of synthetic cannabinoid receptor agonists in human urine using membrane-assisted solvent extraction followed by liquid chromatography-tandem mass spectrometry

“…17 The SCRA isolation from biological uids has also been described by conventional liquid-liquid extraction (LLE) methodologies 18,19 and by miniaturised LLE techniques such as dispersive liquid-liquid microextraction (DLLME) 15,20,21 and ultrasound-assisted dispersive liquid-liquid microextraction (UA-DLLME). 22 Membrane-assisted solvent extraction (MASE) 23 is a small-scale alternative to LLE that uses a semi-permeable and hydrophobic polymeric membrane that separates the aqueous sample (donor phase) from the organic solvent (acceptor phase), so that the two liquid phases are not in direct contact with each other but communicate through the membrane polymer. Typically, the membranes are made of polypropylene (PP), low density polyethylene (LDPE), or other hydrophobic materials.…”

Development of a β-cyclodextrin-modified gold nanoparticle-assisted electromembrane extraction method followed by capillary electrophoresis for methadone determination in plasma

“…In the last few decades, scientists focused on miniaturization, efficiency, sensitivity, and environmentally friendly pretreatment techniques such as solid-phase extraction (SPE), solvent bar microextraction, headspace solid-phase microextraction, liquid-phase microextraction, and electromembrane extraction (EME). 12,13 Among these emerging techniques, fast, excellent sample clean-up and highly selective extraction can be obtained with EME. 14 With this method, charged analytes are extracted across a supported liquid membrane (SLM) on a microporous polypropylene hollow ber (HF) based on electrokinetic migration.…”

Substâncias psicoativas no sangue: métodos de análises toxicológicas e prevalência do uso em pacientes com lesões traumáticas

“…A terceira configuração da LPME, baseada em membrana, é a forma mais conhecida. Utiliza-se de uma membrana semipermeável, porosa, separando fisicamente as fases doadoras e aceptoras, impedindo que moléculas não desejáveis migrem para a fase aceptora do sistema e impossibilitando a dissolução da fase aceptora na matriz aquosa 61,62 . A LPME em membrana porosa é a que apresenta melhores resultados, sendo mais facilmente replicada.…”