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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
Román-Hidalgo Cristina, Martín-Valero María Jesús, Fernández-Torres Rut, Bello-López Miguel Ángel
The use of polymer inclusion membranes (PIMs) as support of 1-octanol liquid membrane in electromembrane extraction (EME) procedure is proposed. Synthesis of PIMs were optimized to a composition of 29% (w/w) of cellulose triacetate as base polymer and 71% (w/w) of Aliquat®336 as cationic carrier. Flat PIMs of 25µm thickness and 6mm diameter were used. EME protocol was implemented for the simultaneous extraction of four non-steroidal anti-inflammatory drugs (NSAIDs) (salicylic acid, ketoprofen, naproxen and ibuprofen) and four highly polar acidic drugs (anthranilic acid, nicotinic acid, amoxicillin and hippuric acid)...
March 1, 2018: Talanta
Joon Hyuk Suh, Sang Beom Han, Yu Wang
Despite their importance in pivotal signaling pathways due to trace quantities and complex matrices, the analysis of plant hormones is a challenge. Here, to improve this issue, we present an electromembrane extraction technology combined with liquid chromatography-tandem mass spectrometry for determination of acidic plant hormones including jasmonic acid, abscisic acid, salicylic acid, benzoic acid, gibberellic acid and gibberellin A4 in plant tissues. Factors influencing extraction efficiency, such as voltage, extraction time and stirring rate were optimized using a design of experiments...
February 2, 2018: Journal of Chromatography. A
Mahroo Baharfar, Yadollah Yamini, Shahram Seidi, Monireh Karami
In this work, a microfluidic device was developed for on-chip electromembrane extraction of trace amounts of ephedrine (EPH) and clonidine (CLO) in human urine and plasma samples followed by HPLC-UV analysis. Two polymethylmethacrylate plates were used as substrates and a microchannel was carved in each plate. The microchannel channel on the underneath plate provided the flow pass of the sample solution and the one on the upper plate dedicated to a compartment for the stagnant acceptor phase. A piece of polypropylene sheet was impregnated by an organic solvent and mounted between the two parts of the chip device...
November 15, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
Monireh Karami, Yadollah Yamini, Yousef Abdossalami Asl, Maryam Rezazadeh
In the present work, an on-chip pulsed electromembrane extraction technique followed by HPLC-UV was developed for the analysis of codeine, naloxone and naltrexone as model analytes in biological fluids. The chip consisted of two channels for the introduction of the donor and acceptor phases. The channels were carved in two poly (methyl methacrylate) plates and a porous polypropylene membrane, which is impregnated by an organic solvent separating the two channels. Two platinum electrodes were mounted on the bottom of these channels and a pulsed electrical voltage was applied as an electrical driving force for the migration of ionized analytes from the sample solution through the porous sheet membrane into the acceptor phase...
December 8, 2017: Journal of Chromatography. A
Andrea Šlampová, Pavel Kubáň
Aqueous and organic phases in microelectromembrane extraction (μ-EME) were formed as adjacent plugs of free immiscible solutions in narrow-bore polymeric tubing, and each single phase was recovered and analyzed after μ-EME. A three-phase μ-EME setup was employed for investigation of time-dependent distribution of model basic drugs among aqueous and organic phases. Exact concentrations of nortriptyline and papaverine in donor solution, acceptor solution, and free liquid membrane (FLM) were determined by capillary electrophoresis with ultraviolet detection (CE-UV)...
December 5, 2017: Analytical Chemistry
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