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Ming Li Tan, Min Zhang, Feng Li, Fernando Maya, Michael C Breadmore
A concentric electromembrane extraction preconcentration device was designed and fabricated using fused deposition modelling 3D printing. The device consisted of a hemispherical electrode sample vial printed from a filament of conductive polylactic acid (PLA), into which sat a smaller hemispherical 3D printed porous membrane acceptor vial. Application of voltage between a point-electrode placed in the center of 20 μL solution inside the acceptor vial and the electrode vial containing 1 mL of sample, enabled anion migration through the 3D printed porous material into the acceptor solution...
February 22, 2019: Journal of Chromatography. A
Mohammadreza Mohammadi Nilash, Fahimeh Mirzaei, Ali Reza Fakhari
In the present research, a new sample preparation method based on SBA-15 assisted electromembrane extraction coupled with corona discharge ion mobility spectrometer was developed for the determination of Thiabendazole as a model basic pesticide in fruit juice samples. In fact, the addition of SBA-15 in the supported liquid membrane in electromembrane extraction system not only can lead to enhancement of the effective surface area, but also introducing the negatively charged silanol groups into supported liquid membrane might improve migration of positively charged analytes toward the supported liquid membrane and finally into the acceptor solution...
February 25, 2019: Journal of Separation Science
Saied Saeed Hosseiny Davarani, Ahmad Pourahadi, Peivand Ghasemzadeh
An electromembrane extraction followed by HPLC-UV technique was developed and validated for quantification of leuprolide and triptorelin in rabbit plasma. The influencing parameters on the extraction efficiency were optimized using experimental design methodology. The optimized conditions were found to be; supported liquid membrane: a mixture of 1-octanol and 2-ethyl hexanol (1:1) containing 10% (v/v) di(2-ethylhexyl) phosphate, applied voltage: 5 V, extraction time: 5 min, pH of the donor phase: 4.5 and pH of the acceptor phase: 1...
January 17, 2019: Electrophoresis
Andrea Šlampová, Pavel Kubáň
A dynamic two-phase micro-electromembrane extraction (μ-EME) using electrically induced transfer of charged analytes directly into free liquid membrane (FLM) is proposed as a novel technique for improving enrichment capabilities of μ-EME. The presented set-up employs aqueous sample as donor solution and water immiscible organic solvent (1-octanol) as FLM, which form the two-phase μ-EME system for efficient extraction of model acidic drugs (ibuprofen, ketoprofen, naproxen and diclofenac) from standard solutions, human urine, human serum and wastewater samples...
February 7, 2019: Analytica Chimica Acta
Stig Pedersen-Bjergaard
Analytical microextraction techniques, including solid-phase microextraction (SPME) Arthur & Pawliszyn (Anal Chem 62:2145-2148, 1990), stir bar sorptive extraction (SBSE), Baltussen et al. (J Microcol 11:737-747, 1999), single-drop microextraction (SDME) Jeannot & Cantwell (Anal Chem 68:2236-2240, 1996), hollow-fiber liquid-phase microextraction (HF-LPME) Pedersen-Bjergaard & Rasmussen (Anal Chem 71:2650-2656, 1999), dispersive liquid-liquid microextraction (DLLME) Berijani et al (J Chromatogr A...
December 18, 2018: Analytical and Bioanalytical Chemistry
Fereshteh Zarghampour, Yadollah Yamini, Mahroo Baharfar, Mohammad Faraji
In this study, a new chip was designed for simultaneous extraction of acidic and basic drugs by a single chamber on-chip electromembrane extraction (CEME) followed by high performance liquid chromatography. Diclofenac (DIC) and nalmefene (NAL) were selected as acidic and basic model analytes, respectively. In this device, simultaneous extraction of the analytes was carried out using a single compartment. The chip was composed of three PMMA (polymethyl methacrylate) parts with sandwiched structures and carved spiral microfluidic channels in each part...
December 12, 2018: Analyst
Atyeh Rahimi, Saeed Nojavan
In this study, the application of a mixture of organic solvents as a supported liquid membrane for improving the efficiency of the electromembrane extraction procedure was investigated. The extraction process was followed by HPLC analysis of two model drugs (verapamil and riluzole). In this research, four organic solvents, including 1-heptanol, 1-octanol, 2-nitrophenyl octyl ether and 2-ethyl hexanol were selected as model solvents and different binary mixtures (v/v) (2:1, 1:1 and 1:2) were used as the supported liquid membrane...
October 29, 2018: Journal of Separation Science
María Ramos Payán, Elia Santigosa, Rut Fernández Torres, Miguel Ángel Bello López
For the first time, a novel and versatile microfluidic device was developed to achieve the possibility of combining different extraction principles using a miniaturized approach for the extraction of different classes of analytes. This novel microchip is composed of a sandwich of three poly(methyl methacrylate) (PMMA) layers. Four channels allowed the combination of electromembrane extraction (EME) and liquid-phase microextraction (LPME) in three different ways: (I) EME and LPME, (II) EME and EME, or (III) LPME and LPME...
September 4, 2018: Analytical Chemistry
Nicolas Drouin, Serge Rudaz, Julie Schappler
Extraction of polar endogenous compounds remains an important issue in bioanalysis although different techniques have been evaluated. Among them, electromembrane extraction (EME) is a relevant approach but supported liquid membranes (SLMs) dedicated to polar molecules are still lacking. In this study 22 organic solvents were evaluated as SLMs on a set of 45 polar basic metabolites (log P from -5.7 to 1.5) from various biochemical families. To investigate a large variety of organic solvents, a parallel electromembrane extraction device was used and a constant current approach was applied to circumvent the heterogeneous conductivities of the different SLMs...
September 10, 2018: Journal of Pharmaceutical and Biomedical Analysis
Frederik A Hansen, Drago Sticker, Jörg P Kutter, Nickolaj J Petersen, Stig Pedersen-Bjergaard
This paper reports for the first time nanoliter-scale electromembrane extraction (nanoliter-scale EME) in a microfluidic device. Six basic drug substances (model analytes) were extracted from 70 μL samples of human whole blood, plasma, or urine through a supported liquid membrane (SLM) of 2-nitrophenyl octyl ether (NPOE) and into 6 nL of 10 mM formic acid as an acceptor solution. A DC potential of 15 V was applied across the SLM and served as the driving force for the extraction. The cathode was located in the acceptor solution...
August 7, 2018: Analytical Chemistry
Saeed Nojavan, Hossein Shaghaghi, Turaj Rahmani, Ali Shokri, Mahnaz Nasiri-Aghdam
As a well-known extraction procedure, electromembrane extraction (EME) was combined with electro-assisted liquid-liquid microextraction (EA-LLME) in the present work, which resulted in a promising method. This hyphenated sample preparation method, named EME-EA-LLME, was followed by GC for the determination of two model analytes (clomipramine and imipramine). The effective parameters of both EME and EA-LLME (such as organic solvent, pH of acceptor and sample solutions, voltage and extraction time) were optimized...
August 17, 2018: Journal of Chromatography. A
Mahroo Baharfar, Yadollah Yamini, Shahram Seidi, Muhammad Balal Arain
A design of electromembrane extraction (EME) as a lab on-a-chip device was proposed for the extraction and determination of phenazopyridine as the model analyte. The extraction procedure was accomplished by coupling EME and packing a sorbent. The analyte was extracted under the applied electrical field across a membrane sheet impregnated by nitrophenyl octylether (NPOE) into an acceptor phase. It was followed by the absorption of the analyte on strong cation exchanger as a sorbent. The designed chip contained separate spiral channels for donor and acceptor phases featuring embedded platinum electrodes to enhance extraction efficiency...
July 17, 2018: Analytical Chemistry
Saeid Yaripour, Ali Mohammadi, Isa Esfanjani, Roderick B Walker, Saeed Nojavan
In this study, for the first time, an electro-driven microextraction method named electromembrane extraction combined with a simple high performance liquid chromatography and ultraviolet detection was developed and validated for the quantitation of zolpidem in biological samples. Parameters influencing electromembrane extraction were evaluated and optimized. The membrane consisted of 2-ethylhexanol immobilized in the pores of a hollow fiber. As a driving force, a 150 V electric field was applied to facilitate the analyte migration from the sample matrix to an acceptor solution through a supported liquid membrane...
2018: EXCLI Journal
Macarena Silva, Carolina Mendiguchía, Carlos Moreno, Pavel Kubáň
Simultaneous electromembrane extraction (EME) of six trace metal cations (Cu2+ , Zn2+ , Co2+ , Ni2+ , Pb2+ , Cd2+ ) from saline samples was investigated. CE with capacitively coupled contactless conductivity detection (C4 D) was used to determine the metals in acceptor solutions due to its excellent compatibility with the minute volumes of acceptor solutions. Bis(2-ethylhexyl)phosphate (DEHPA) was selected as a suitable nonselective modifier for EME transport of target metal cations. Both, the individual effect of each major inorganic cation (Na+ , K+ , Ca2+ , Mg2+ ) and their synergistic effect on EME of the trace metal cations were evaluated...
August 2018: Electrophoresis
Zeinab Tahmasebi, Saied Saeed Hosseiny Davarani, Ali Akbar Asgharinezhad
In this work, a novel, inexpensive and fast strategy was described for selective and effective extraction and determination of propylthiouracil (PTU) with a high polarity (log P = 1.2) based on electromembrane extraction (EME) followed by differential pulse voltammetry (DPV). For this purpose, copper nanoparticles (CuNPs)-decorated hollow fiber was used as the selective membrane for EME of PTU in urine samples. The influential parameters on extraction such as extraction solvent, pH, agitation speed, applied potential and extraction time were systematically investigated...
August 30, 2018: Biosensors & Bioelectronics
Linda Vårdal, Elisabeth L Øiestad, Astrid Gjelstad, Stig Pedersen-Bjergaard
AIM: Electromembrane extraction (EME) of weakly basic benzodiazepines was investigated (-1.47 < pKa < 5.01). MATERIALS & METHODS: 96-well EME was performed with strongly acidic conditions in the acceptor solution using 250-mM trifluoroacetic acid to maximize ionization. RESULTS & CONCLUSION: Recoveries more than 80% were obtained for analytes with pKa > 2, whereas EME was less efficient for substances with pKa < 2...
May 1, 2018: Bioanalysis
Fereshteh Zarghampour, Yadollah Yamini, Mahroo Baharfar, Mohammad Faraji
In the present research, an on-chip electromembrane extraction coupled with high performance liquid chromatography was developed for monitoring the trace levels of biogenic amines (BAs), including histamine, tryptamine, putrescine, cadaverine and spermidine in food samples. A porous polypropylene sheet membrane impregnated with an organic solvent was placed between the two parts of the chip device to separate the channels. Two platinum electrodes were mounted at the bottom of these channels, which were connected to a power supply, providing the electrical driving force for migration of ionized analytes from the sample solution through the porous sheet membrane into the acceptor phase...
June 29, 2018: Journal of Chromatography. A
Stig Pedersen-Bjergaard, Chuixiu Huang, Astrid Gjelstad
Electromembrane extraction (EME) is an analytical microextraction technique, where charged analytes (such as drug substances) are extracted from an aqueous sample (such as a biological fluid), through a supported liquid membrane (SLM) comprising a water immiscible organic solvent, and into an aqueous acceptor solution. The driving force for the extraction is an electrical potential (dc) applied across the SLM. In this paper, EME is reviewed. First, the principle for EME is explained with focus on extraction of cationic and anionic analytes, and typical performance data are presented...
June 2017: Journal of Pharmaceutical Analysis
Miloš Dvořák, Knut Fredrik Seip, Stig Pedersen-Bjergaard, Pavel Kubáň
Manual handling of microliter volumes of samples and reagents is usually prone to errors and may have direct consequence on the overall performance of microextraction process. Direct connection of a syringe pump and a disposable microextraction unit using flexible polymeric tubing was employed for semi-automated liquid handling in micro-electromembrane extraction (μ-EME). A three-phase μ-EME system was formed by consecutive withdrawal of microliter volumes of donor solution, free liquid membrane (FLM) and acceptor solution into the unit...
April 16, 2018: Analytica Chimica Acta
Sakine Asadi, Hadi Tabani, Saeed Nojavan
Introducing new membranes with green chemistry approach seems to be a great challenge for the development of a practical method in separation science. In this regard, for the first time, polyacrylamide gel as a new membrane in electromembrane extraction (EME) was used for the extraction of three model basic drugs (pseudoephedrine (PSE), lidocaine (LID), and propranolol (PRO)), followed by HPLC-UV. In comparison with conventional EME, in this method neither organic solvent nor carrier agents were used for extraction of mentioned drugs...
March 20, 2018: Journal of Pharmaceutical and Biomedical Analysis
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