New robust and efficient liquid membranes for conductive vial electromembrane extraction of acids with low to moderate hydrophilicity in human plasma.

The current paper reports two new, robust, and efficient conditions for electromembrane extraction of acidic substances from human plasma. Two systems were developed based on eutectic solvents: A1 ("A" for acid) comprised dodecyl methyl sulfoxide and thymol in 1:2 ratio (w/w) as liquid membrane, while A2 used [6-methylcoumarin:thymol (1:2)]:2-nitrophenyl octyl ether in 2:1 ratio (w/w). The performance of A1 and A2 was characterized by extraction of 31 acidic model analytes (pharmaceutical drugs and nutrients) spiked into 100 µL human plasma diluted 1:1 (v/v) with phosphate buffer pH 7.

Electromembrane extraction of peptides based on charge, hydrophobicity, and size - A large-scale fundamental study of the extraction window.

This study investigated the capability of electromembrane extraction (EME) as a general technique for peptides, by extracting complex pools of peptides comprising in total of 5953 different substances, varying in size from seven to 16 amino acids. Electromembrane extraction was conducted from a sample adjusted to pH 3.0 and utilized a liquid membrane consisting of 2-nitrophenyl octyl ether and carvacrol (1:1 w/w), containing 2% (w/w) di(2-ethylhexyl) phosphate.

Parallel electromembrane extraction of peptides with monoterpene and medium-length fatty acid deep eutectic solvents.

Background: Electromembrane extraction (EME) involves the process of mass transfer of charged analytes from an aqueous sample through an organic liquid membrane into an aqueous acceptor medium under the influence of an electrical field. Successful solvation of the analyte within the liquid membrane is of paramount importance and involves molecular interactions with the liquid membrane. In this comprehensive investigation, parallel EME was examined using a training set of 13 model peptides employing deep eutectic solvents as the liquid membrane.

Generic conditions for electromembrane extraction of polar bases.

The current paper reports the first generic conditions for electromembrane extraction (EME) of polar bases within -2.0 < log P < 1.0 from human plasma.

Electromembrane extraction of peptides based on hydrogen bond interactions.

Background: Electromembrane extraction (EME) of peptides reported in the scientific literature involve transfer of net positively charged peptides from an aqueous sample, through a liquid membrane, and into an aqueous acceptor solution, under the influence of an electrical field. The liquid membrane comprises an organic solvent, containing an ionic carrier. The purpose of the ionic carrier is to facilitate peptide solvation in the organic solvent based on ionic interactions.

Generic Liquid Membranes for Electromembrane Extraction of Bases with Low or Moderate Hydrophilicity.

For the first time, this paper introduces the idea of generic extraction conditions in electromembrane extraction (EME), where the selection of the liquid membrane is based on the charge () and hydrophobicity (log ) of the analyte. A broad range of organic solvents were tested as liquid membranes, and 90 basic pharmaceuticals were used as model analytes (-4.2 < log < 8.

A green microfluidic method based liquid phase microextraction for the determination of parabens in human urine samples.

Development of green approaches have emerged as a challenge that highlight the pressing need for nontoxic solvents, miniaturized method and bio-degradable materials. In this regard, an environmentally-friendly microfluidic system based on natural deep eutectic solvents (DESs) immobilized in agarose membranes was developed to extract parabens from urine samples for the first time. A comprehensive study of the support liquid membrane showed that only 3 µL of camphor and thymol (2:1 molar ratio) was an interesting option as a substitute for conventional (toxic) solvents used to date.

Microfluidic liquid-phase microextraction based on natural deep eutectic solvents immobilized in agarose membranes.

In liquid-phase microextraction (LPME), the sample and the acceptor are separated by a synthetic organic solvent, which is immobilized in a porous polymeric membrane of polypropylene or polyvinylidene fluoride. The organic solvent serves as extraction phase, while the polymeric membrane serves as support membrane. The combination of extraction phase and support membrane is termed supported liquid membrane (SLM).

A microchip device based liquid-liquid-solid microextraction for the determination of permethrin and cypermethrin in water samples.

In this work, for the first time, a microchip device integrating liquid-liquid-solid phase microextraction is presented. As a novel approach to microchip systems, liquid-liquid-solid microextraction was performed in a sandwiched microchip device. The microchip device consisted of three poly(methyl methacrylate) layers along with a double "Y"-shaped microchannel.

A selective and efficient microfluidic method-based liquid phase microextraction for the determination of sulfonamides in urine samples.

Liquid phase microextraction (LPME) into a microfluidic has undergone great advances focused on downscaled and miniaturized devices. In this work, a microfluidic device was developed for the extraction of sulfonamides in order to accelerate the mass transfer and passive diffusion of the analytes from the donor phase to the acceptor phase. The subsequent analysis was carried out by high performance liquid chromatography with UV-DAD (HPLC-DAD).

A novel nanocomposite based on covalent organic polymer and nanocellulose for thin-film microextraction of imipramine from biological samples.

A novel covalent organic polymer was prepared using 1,5-diaminonaphthalene as a linker and cyanuric chloride as a node. A thin-film nanocomposite of 1,5-diaminonaphthalene covalent organic polymer and cellulose nanocrystalline was then fabricated via filtering and casting method. The effect of incorporation of various amounts of 1,5-diaminonaphthalene covalent organic polymer and cellulose nanocrystalline was studied to obtain an efficient nanocomposite thin-film with a large number of polar functional groups and high mechanical stability.

A silica-based three-dimensional molecularly imprinted coating for the selective solid-phase microextraction of difenoconazole from wheat and fruits samples.

In this work, a selective silica-based molecular imprinted solid-phase microextraction (SPME) sorbent was prepared through the sol-gel process. Difenoconazole was used as a template to prepare imprinted materials on the surface of mesoporous silica. The SPME fiber followed by gas chromatography-electron capture detection was applied for the extraction and determination of difenoconazole.

A solid-phase microextraction platinized stainless steel fiber coated with a multiwalled carbon nanotube-polyaniline nanocomposite film for the extraction of thymol and carvacrol in medicinal plants and honey.

A mechanically hard and cohesive porous fiber, with large surface area, for more strong attachment of the coating was provided by platinizing a stainless steel wire. Then, the platinized stainless steel fiber was coated with a multiwalled carbon nanotube/polyaniline (MWCNT/PANI) nanocomposite using electrophoretic deposition (EPD) method and applied for the extraction of thymol and carvacrol with direct-immersion solid-phase microextraction (DI-SPME) method followed by high-performance liquid chromatography-ultraviolet detection (HPLC-UV) quantification. To provide a larger coarse surface for the tightened attachment of coating on the fiber, a stainless steel wire was platinized using a suitable optimized EPD method.