Publications by authors named "Yadollah Yamini"

203 Publications

Dispersive magnetic solid phase microextraction on microfluidic systems for extraction and determination of parabens.

Anal Chim Acta 2021 Dec 23;1188:339183. Epub 2021 Oct 23.

Department of Chemistry, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran.

In this study, a customized microfluidic system was utilized for magnetic solid phase extraction of parabens. For this sake, magnetite nanoparticles were synthesized and coated with polyaniline to enable efficient extraction and magnetic separation of sorbents particles. The synthesized particles were extensively characterized in terms of morphology, composition, and magnetic properties. The utilized microfluidic platform consisted of a relatively long spiral microchannel fabricated through laser-cutting and multi-layered assembly. To obtain an efficient dispersion, simultaneous flows of sample solution and magnetic beads dispersion were introduced to the chip with the aid of two syringe pumps. In order to increase the stability of the dispersed nanoparticles in the aqueous solution, various chemical and instrumental parameters were investigated and optimized. In this context, exploitation of hydrophobic surfactants and surface charge manipulation of the particles was shown to be a highly promising approach for effective dispersion and maintenance of magnetic beads in long microfluidic channels. Under the optimized conditions, the calibration curves were linear in the range of 5.0-1000.0 μg L for propyl paraben and 8.0-1000.0 μg L for methyl- and ethyl paraben with coefficients of determination greater than 0.992. Relative standard deviations were assessed as intra- and inter-day values which were less than 7.2% and the preconcentration factors in water were 10-15 for 100 μg L of parabens in water. Finally, the method was applied for the extraction of parabens from fruit juice, sunscreen, and urine samples which showed favorable accuracy and precision.
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http://dx.doi.org/10.1016/j.aca.2021.339183DOI Listing
December 2021

Plugged bifunctional periodic mesoporous organosilica as a high-performance solid phase microextraction coating for improving extraction efficiency of chlorophenols in different matrices.

Talanta 2021 Dec 20;235:122724. Epub 2021 Jul 20.

Department of Chemistry, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran.

In this study, a sensitive solid phase microextraction (SPME) coating was developed based on two kinds of plugged and non-plugged bifunctional periodic mesoporous organosilicas (BFPMO) with ionic liquid and ethyl units. The extraction efficiency of all plugged and unplugged sorbents was investigated for the extraction of chlorophenols (CPs) in water and honey samples by emphasizing the effect of different physicochemical properties. The separation and determination of the CPs was performed by gas chromatography-mass spectrometry (GC-MS). The extraction results showed that plugged BFPMO coating exhibited outstanding enrichment ability for the extraction of CPs as model analytes with different polarities. This can be attributed to a valuable hydrophobic-hydrophilic balance in the mesochanels of the plugged BFPMO, which is the result of the combination of plug technology and bridged organic groups. Low limits of detection in the range of 5-70 ng L, wide linearity, and good reproducibility (RSD = 8.1-10.1 % for n = 6) under the optimized extraction conditions were achieved. Finally, the BFPMOs coated fiber was successfully used for determination of CPs in real water samples. The relative recoveries for the five CPs were in the range of 92.3-104.0 %, which proved the applicability of the method.
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http://dx.doi.org/10.1016/j.talanta.2021.122724DOI Listing
December 2021

Molecularly imprinted [email protected] nanocomposite as an in-tube solid-phase microextraction coating for selective extraction of carbamazepine from biological samples.

J Pharm Biomed Anal 2021 Sep 13;204:114256. Epub 2021 Jul 13.

Department of Neurology, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran.

A nanocomposite of molecularly imprinted polypyrrole on copper oxide ([email protected]) was introduced as a new coating for in-tube solid-phase microextraction (IT-SPME). The method coupled with HPLC-UV was successfully applied for analysis of carbamazepine (anticonvulsant and bipolar disorder medication) in biological samples. First, in order to increase the surface area and stability of the coating, copper oxide (CuO) nanosheets were synthesized on the inner surface of a copper tube using a chemical method. Then, molecularly imprinted polypyrrole coating (using carbamazepine as a template) was deposited on CuO by a facile in-situ electrodeposition method. According to the results, The [email protected] coating shows long life time, enhanced extraction efficiency, and good clean-up, for pre-concentration and determination of carbamazepine in biological samples. The synthesized adsorbent also showed high selectivity to carbamazepine compared to other drugs with similar structure. Important factors affecting the extraction efficiency of the analyte in the in-tube SPME method, such as salt concentration, extraction and desorption times, flowrates of the sample solution, and eluent, were optimized. Under optimal conditions, the method showed good linearity for carbamazepine in the range of 0.05-500 μg L, 0.10-500 μg L, and 0.10-500 μg L in water, urine, and plasma samples, respectively, with coefficients of determination better than 0.996. The limits of detection were in the range of 0.01-0.05 μg L in different matrices. The intra- and inter-assay precisions (RSD%, n = 3) were in the range of 6.7-8.1 % and 7.1-9.5 %, respectively.
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http://dx.doi.org/10.1016/j.jpba.2021.114256DOI Listing
September 2021

Environmental impact assessment of salt harvesting from the salt lakes.

J Environ Health Sci Eng 2021 Jun 26;19(1):365-377. Epub 2021 Jan 26.

Department of Chemistry, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran.

Urmia Saline Lake, USL which is registered as an international park by the United Nations, has suffered hypersalinity and serious dryness in recent years. Increasing the dryness trend has been led to a great tendency, especially by private sectors to harvest salt from different parts of the bed sediments. During this study the four- step process was used for environmental impact assessment of such a large scale salt harvesting activities with specialized Folchi matrix and enriched by data on heavy metal concentrations in the limited number of sediment samples. Impact analysis using matrix showed that the most significant impacts were on environmental components, namely "land use", "gradient and topography of the lake bed" and "hydrology and lake water quality" with score values of 73.22, 73.21 and 72.45, respectively. The mean concentrations of As, Cd, Cr, Hg, Pb, Ni and Zn in salt and sediment samples were 15.2±8.8, 0.05±0.047, 15±8.2, 0.54±0.3, 11.9±6.28, 15.4±9.56 and 22.3±13.66 mg/kg, respectively. The higher concentration of arsenic and lead in comparison with earth crust averages, warns that dispersion of salt particles from storage piles may affect local people's health. This study provides readers and authorities with environmental impacts of salt harvesting from unique saline Lake of Iran, presents effective management options such as stopping any unlicensed and unrestrained salt harvesting activities on the USL bed, avoiding deep excavations, minimizing accumulation of piles to prevent the diffusion of salt particles etc. and also specialized the Folchi matrix for application in similar projects.
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http://dx.doi.org/10.1007/s40201-020-00609-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8172734PMC
June 2021

Application of HKUST-1 metal-organic framework as coating for headspace solid-phase microextraction of some addictive drugs.

J Sep Sci 2021 Jul 25;44(14):2814-2823. Epub 2021 May 25.

Chemistry & Chemical Engineering Research Center of Iran, Tehran, Iran.

In the present study, a copper-based metal-organic framework (HKUST-1) was used first time for preconcentration trace amounts of addictive drugs in biological samples. HKUST-1 was synthesized and coated onto the surface of stainless steel wire. The prepared coating was used in headspace solid-phase microextraction method coupled with gas chromatography-mass spectrometry for preconcentration and determination of some addictive drugs in biological fluids. Prepared coating shows good extraction efficiency due to large surface area, and π-π stacking interaction with selected analytes. Under optimum conditions, the method was validated with a reasonable determination coefficient (R  > 0.9961) and suitable linear dynamic range (0.5-1000 μg L ). Also, the limits of detections were obtained in the range of 0.1-0.4, 0.2-0.6, and 0.4-0.7 μg L for water, urine, and plasma samples, respectively. The limits of quantification of present method were obtained in the range 0.5-1.3, 0.7-1.5, and 1.0-1.9 μg L in water, urine, and plasma samples, respectively. The intra-day and inter-dye single fiber and fiber to fiber relative standard deviations were observed in the range 3.0-13.9% and 3.5-12.3%, respectively. Finally, the present method was applied for the determination of the drugs in biological samples.
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http://dx.doi.org/10.1002/jssc.202100070DOI Listing
July 2021

Applications of porous frameworks in solid-phase microextraction.

J Sep Sci 2021 Mar 25;44(6):1231-1263. Epub 2021 Jan 25.

Department of Chemistry, Tarbiat Modares University, Tehran, Iran.

Porous frameworks are a term of attracting solid materials assembled by interconnection of molecules and ions. These trendy materials due to high chemical and thermal stability, well-defined pore size and structure, and high effective surface area gained attention to employ as extraction phase in sample pretreatment methods before analytical analysis. Solid-phase microextraction is an important subclass of sample preparation technique that up to now different configurations of this method have been introduced to get adaptable with different environments and analytical instruments. In this review, theoretical aspect and different modes of solid-phase microextraction method are investigated. Different classes of porous frameworks and their applications as extraction phase in the proposed microextraction method are evaluated. Types and features of supporting substrates and coating procedures of porous frameworks on them are reviewed. At the end, the prospective and the challenges ahead in this field are discussed.
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http://dx.doi.org/10.1002/jssc.202001172DOI Listing
March 2021

Microfluidic-enabled versatile hyphenation of electromembrane extraction and thin film solid phase microextraction.

Talanta 2021 Mar 5;224:121864. Epub 2020 Nov 5.

Department of Analytical Chemistry, Faculty of Chemistry, K. N. Toosi University of Technology, Tehran, Iran.

In the present study, a versatile combination of electromembrane extraction (EME) with thin film solid phase microextraction (TF-SPME) was introduced using a microfluidic chip device. The device consisted of two single channels on two separate layers. The upper channel was dedicated to donor phase flow pass, while the beneath channel was used as a reservoir for stagnant acceptor solution. A slide of fluorine doped tin oxide (FTO) was accommodated in the bottom of the acceptor phase channel. A thin layer of polyaniline was electrodeposited on the FTO surface to achieve the required thin film for TF-SPME. A stainless-steel wire was embedded in the donor phase channel and another wire was also attached to the FTO surface. The channels were separated by a piece of polypropylene membrane impregnated with 1-octanol and the whole chip was fixed with bolts and nuts. The driving force for the extraction was an 8 V direct current (DC) voltage applied across the supported liquid membrane (SLM). Under the influence of the electrical field, analytes immigrated from sample towards the acceptor phase and then adsorbed on the thin film of the solid phase. Finally, the analytes were desorbed by successive movement of a desorption solvent in the acceptor phase channel followed by injection of the desorption solution to HPLC-UV. The applicability of the proposed device was demonstrated by the determination of four synthetic food dyes: Amaranth, Ponceau 4R, Allura Red, and Carmoisine, as the model analytes. The effective parameters on the efficiency of the both EME and TF-SPME were investigated. Under the optimized conditions, the microchip provided low LODs (1-10 μg L), and a wide linear dynamic range of 10-1000 μg L for all analytes. The system also offered RSD values lower than 5.5% and acceptable reusability of the thin film for multiple extractions.
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http://dx.doi.org/10.1016/j.talanta.2020.121864DOI Listing
March 2021

Deep eutectic solvent dependent carbon dioxide switching as a homogeneous extracting solvent in liquid-liquid microextraction.

J Chromatogr A 2021 Jan 5;1636:461756. Epub 2020 Dec 5.

Department of Chemistry, Tarbiat Modares University, Tehran, Iran.

A miscible-immiscible deep eutectic solvent (DES) containing monoethanolamine/4-methoxyphenol was used as an extraction solvent in a homogeneous liquid-liquid microextraction (HLLME). The method was used to preconcentrate chlorobenzenes in water samples followed by separating and analyzing them by gas chromatography-mass spectroscopy (GC-MS). A special feature of the new extraction method is that a green miscible solvent was used as an extractant in the HLLME method. The developed extraction technique provided enrichment factors in the range of 13.1-42.1 for extraction from only 1.0 mL of the aqueous sample solution. The effects of various experimental parameters were investigated and optimized. The optimal conditions were as follows: vortex time: 30.0 s, bubbling CO gas: 1.0 min, salt concentration: 5.0% w/v, rate and time of centrifuge: 4000.0 rpm and 3.0 min, respectively, and DES volume: 30.0 µL. The limit of detections and the limit of quantifications for the four targeted analytes varied from 0.01-0.15 and 0.025-0.5 µg L, respectively. The precision and long-term precision tests for the developed method were found to be less than 11.0%. Two real samples, including toilet air freshener and car perfume, were analyzed. The applied DES in the HLLME method provides a fast means of sample preparation for environmental aqueous sample solutions.
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http://dx.doi.org/10.1016/j.chroma.2020.461756DOI Listing
January 2021

Covalent organic framework and montomorillonite nanocomposite as advanced adsorbent: synthesis, characterization, and application in simultaneous adsorption of cationic and anionic dyes.

J Environ Health Sci Eng 2020 Dec 27;18(2):1555-1567. Epub 2020 Oct 27.

Department of Chemistry, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran.

In this work, Schiff base network-1 (SNW-1), as a new generation of covalent organic frameworks (COFs), was synthesized and modified by fabrication of a composite with clay mineral montomorillonite (Mt). It was used for simultaneous removal of anionic and cationic dyes from aqueous solutions. The fabricated composite was characterized successfully with various techniques. Tartrazine (TT) and methylene blue (MB) were selected as model anionic and cationic dyes, respectively. The effects of the percentage of each component in the composite, initial pH, and initial dye concentration were evaluated on the adsorption capacity. Adsorption reaction models and adsorption diffusion models were used to study the kinetic process of adsorption. Adsorption of both dyes reached equilibrium after 40 min. The obtained results were fitted to Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich (D-R) models to predict the isotherms of adsorption. Under optimum conditions for removal of each dye with the composite, the maximum adsorption capacity of 519.2 and 602.7 mg g were obtained for TT and MB, respectively. The used SNW-1/Mt composite could be regenerated by salty methanol. The high adsorption capacity and excellent reusability make SNW-1/Mt composite attractive for the simultaneous removal of anionic and cationic dyes from aqueous solutions.
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http://dx.doi.org/10.1007/s40201-020-00572-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7721761PMC
December 2020

Application of magnetic nanomaterials in magnetic in-tube solid-phase microextraction.

Talanta 2021 Jan 15;221:121648. Epub 2020 Sep 15.

Department of Chemistry, Faculty of Sciences, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran. Electronic address:

Development of magnetic nanomaterials has greatly promoted the innovation of in-tube solid-phase microextraction. This review article gives an insight into recent advances in the modifications and applications of magnetic nanomaterials for in-tube solid-phase microextraction. Also, different magnetic nanomaterials which have recently been utilized as in-tube solid-phase microextraction sorbents are classified. This study shows that magnetic nanomaterials have gained significant attention owing to large specific surface area, selective absorption, and surface modification. Magnetic in-tube solid-phase microextraction has been applied for the analysis of food samples, biological, and environmental. However, for full development of magnetic in-tube SPME, effort is still needed to overcome limitations, such as mechanical stability, selectivity and low extraction efficiency. To achieve these objectives, research on magnetic in-tube SPME is mainly focused in the preparation of new extractive phases.
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http://dx.doi.org/10.1016/j.talanta.2020.121648DOI Listing
January 2021

Electrodeposition of poly-ethylenedioxythiophene-graphene oxide nanocomposite in a stainless steel tube for solid-phase microextraction of letrozole in plasma samples.

J Sep Sci 2020 Dec 15;43(23):4338-4346. Epub 2020 Oct 15.

Department of Chemistry, Faculty of Sciences, Tarbiat Modares University, Tehran, Iran.

Coated stainless steel was used as an in-tube solid-phase microextraction for the extraction of letrozole from plasma samples. The coating process on the inner surface of the stainless steel was conducted by a simple electrodeposition process. The coated composite was prepared from 3,4-ethylenedioxythiophene and graphene oxide. In this composite, graphene oxide acts as an anion dopant and sorbent. The coated nanostructured polymer was characterized using different techniques. The operational factors affecting the extraction process, including pH, adsorption, and desorption time, the recycling flow rate of the sample solution, sample volume, desorption solvent type and its volume, and ionic strength were optimized to achieve the best extraction efficiency of the analyte. The total extraction time including adsorption and desorption steps was about 15.0 min. The developed method demonstrated a linear range of 5.0-1500.0 μg/L with a limit of detection of 1.0 μg/L. The repeatability of the developed extraction approach in terms of intraday, interday, and fiber to fiber was attained in the range of 4.9-8.3%. After finding the optimal conditions, the potential of the described approach for letrozole quantitation was investigated in plasma samples, and satisfactory results were obtained.
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http://dx.doi.org/10.1002/jssc.202000838DOI Listing
December 2020

Microextraction on a screw for determination of trace amounts of hexanal and heptanal as lung cancer biomarkers.

J Pharm Biomed Anal 2020 Nov 22;191:113528. Epub 2020 Aug 22.

Department of Chemistry, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran.

Solid phase microextraction on a screw was utilized for the extraction of hexanal and heptanal as lung cancer biomarkers from urine samples. Reduced graphene oxide (rGO) was coated on the surface of a stainless-steel set screw by electrophoretic deposition method. The screw was located inside a glass cover, and the created channel acted as the sample solution flow pass. A 5 mL glass syringe was connected to a syringe pump to direct the sample and the eluent through the channel. The extraction procedure was followed by gas chromatography/mass spectrometry (GC/MS) for separation and determination of the extracted aldehydes. The effective parameters on the extraction efficiencies of the analytes were identified and optimized. Under the optimal extraction conditions, the extraction time was as short as 10 min. The calibration curves indicated good linearity (R > 0.97) within the concentration range of 1.0-50 μg L. The obtained limits of detection (LODs) for hexanal and heptanal were down to 0.4 and 0.3 μg L, respectively. Considering the repeatability, simplicity, and eco-friendliness of this simple extraction method, it can be efficiently used for preconcentration of aldehydes in different samples.
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http://dx.doi.org/10.1016/j.jpba.2020.113528DOI Listing
November 2020

Facile magnetization of metal-organic framework TMU-6 for magnetic solid-phase extraction of organophosphorus pesticides in water and rice samples.

Talanta 2020 Oct 15;218:121139. Epub 2020 May 15.

Department of Chemical Engineering, Kermanshah University of Technology, Kermanshah, Iran.

In the present work, a magnetic metal-organic framework composite ([email protected]@TMU-6) was synthesized and used as an adsorbent for magnetic solid-phase extraction (MSPE) of some organophosphorus pesticides (phosalone, chlorpyrifos and, profenofos) in rice and environmental water samples. Extraction, separation and determination of the analytes were performed by MSPE-HPLC-UV. Due to the large surface area and unique porous structure of the metal-organic frameworks (MOFs) as well as π-π and hydrophobic interactions between the analytes and the MOF ligands, the prepared sorbents showed a high affinity towards the target analytes. The affecting parameters on the extraction efficiency, including type and volume of eluent, pH, amount of MFC, extraction time, salt effect and desorption time were investigated and optimized. Under optimum conditions, calibration curves were found to be linear in the range of 7.5-75 μg L, 10-100 μg L, and 10-150 μg L for phosalone, chlorpyrifos, and profenofos in water samples, respectively. The LODs (based on S/N = 3) were 0.5, 1 and 0.5 μg L for phosalone, chlorpyrifos, and profenofos in water samples, respectively.
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http://dx.doi.org/10.1016/j.talanta.2020.121139DOI Listing
October 2020

Synthesis of an organic-inorganic hybrid absorbent for in-tube solid-phase microextraction of bisphenol A.

J Sep Sci 2021 Mar 20;44(6):1122-1129. Epub 2020 Jul 20.

Department of Chemistry, Faculty of Sciences, Tarbiat Modares University, Tehran, Iran.

This research is an application of fiber-in-tube solid-phase microextraction followed by high-performance liquid chromatography with UV detection for the extraction and determination of trace amounts of bisphenol A. Nanomagnetic Fe O was formed on the surface of polypropylene porous hollow fibers to increase the surface area and then it was coated with polystyrene. The introduction of polystyrene improves the surface hydrophobicity and is an appropriate extractive phase because it is highly stable in aquatic media. The extraction was carried out in a short capillary packed longitudinally with the fine fibers as the extraction medium. Extraction conditions, including extraction and desorption flow rates, extraction time, pH, and ionic strength of the sample solution, were investigated and optimized. Under optimal conditions, the limit of detection was 0.01 µg/L. This method showed good linearity for bisphenol A in the range of 0.033-1000 µg/L, with the coefficient of determination of 0.9984. The inter- and intraday precisions (RSD%, n = 3) were 7.9 and 6.3%, respectively. Finally, the method was applied to analysis of the analyte in thermal papers, disposable plastic cups, and soft drink bottles.
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http://dx.doi.org/10.1002/jssc.202000526DOI Listing
March 2021

Hollow fiber-based liquid phase microextraction followed by analytical instrumental techniques for quantitative analysis of heavy metal ions and pharmaceuticals.

J Pharm Anal 2020 Apr 12;10(2):109-122. Epub 2019 Dec 12.

Department of Chemistry, Tarbiat Modares University, P. O. Box 14115-175, Tehran, Iran.

Hollow-fiber liquid-phase microextraction (HF-LPME) and electromembrane extraction (EME) are miniaturized extraction techniques, and have been coupled with various analytical instruments for trace analysis of heavy metals, drugs and other organic compounds, in recent years. HF-LPME and EME provide high selectivity, efficient sample cleanup and enrichment, and reduce the consumption of organic solvents to a few micro-liters per sample. HF-LPME and EME are compatible with different analytical instruments for chromatography, electrophoresis, atomic spectroscopy, mass spectrometry, and electrochemical detection. HF-LPME and EME have gained significant popularity during the recent years. This review focuses on hollow fiber based techniques (especially HF-LPME and EME) of heavy metals and pharmaceuticals (published 2017 to May 2019), and their combinations with atomic spectroscopy, UV-VIS spectrophotometry, high performance liquid chromatography, gas chromatography, capillary electrophoresis, and voltammetry.
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http://dx.doi.org/10.1016/j.jpha.2019.12.003DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7192972PMC
April 2020

Polyoxomolybdate /polyaniline nanocomposite as a novel fiber for solid-phase microextraction of antidepressant drugs in biological samples.

J Sep Sci 2020 Jul 4;43(13):2636-2645. Epub 2020 May 4.

Department of Chemistry, Amir Kabir University of Technology, Tehran, Iran.

A novel solid-phase microextraction fiber was synthesized by coating a stainless steel wire with polyoxomolybdate /polyaniline as a sorbent aimed at extraction of amitriptyline, nortriptyline, and doxepin as antidepressant drugs from urine and blood samples. The polyoxomolybdate /polyaniline composite coating was applied using electropolymerization process under constant potential. This composition leads to enhanced extraction efficiency of the fiber. Scanning electron microscopy images show that huge three-dimensional structures of polyoxomolybdate in composite induced more non-smooth and porous fiber. In order to optimize of the extraction process, a series of variables including concentration of the composite materials, coating thickness, pH, extraction time, salt addition, and stirring rate was investigated and optimum conditions were determined. Analysis of surface morphology and chemical composition was performed. High-performance liquid chromatography was used for separation and evaluation of mentioned antidepressant drugs from the matrixes. The experiments indicated a detection limits of <0.2 ng/L and a linear dynamic range of 0.3-100 ng/L (R > 0.994). The relative recovery values were found to be in the range of 92-98%. It was concluded that the purposed fiber is highly efficient in analyzing traces of antidepressant drugs in urine and blood.
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http://dx.doi.org/10.1002/jssc.201901152DOI Listing
July 2020

Reduced graphene-decorated covalent organic framework as a novel coating for solid-phase microextraction of phthalate esters coupled to gas chromatography-mass spectrometry.

Mikrochim Acta 2020 04 2;187(4):256. Epub 2020 Apr 2.

Department of Chemistry, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran.

Schiff base network-1 (SNW-1), as a new generation of covalent organic frameworks (COFs), was synthesized and modified by fabrication of a composite with graphene oxide (GO). The fabricated nanocomposite was characterized with FT-IR spectroscopy, XRD, FE-SEM, EDX, TGA, and the nitrogen adsorption-desorption technique. Characterization results showed that SNW-1 can reduce GO during the fabrication procedure and produce an effective and stable nanocomposite. This nanocomposite was deposited on the surface of a stainless steel wire via a single phase inversion method with the help of polyethersulfone, as a porous adhesive material. This robust and stable coating was used for head space solid-phase microextraction of phthalate esters (PhEs) from water samples. Determination of the PhEs was performed with gas chromatography coupled to mass spectrometry. SNW-1 is N-rich, and reduced-GO is full of hexagonal conjugated rings. Therefore, due to hydrogen binding and π-interaction, the coating has a high tendency to PhEs. Effective adsorption and desorption parameters were optimized. The performance of the method was evaluated in terms of linear ranges (LRs from 0.05 to 100 μg L with R ≥ 0.9942) and limits of detection (LODs in the range of 0.01-0.50 μg L). The average repeatability and fiber-to-fiber reproducibility were 6.8% and 9.2%, respectively. The method was employed to trace determination of PhEs in drinking water and pickled cucumber solution with good recovery (80.5-111.0%) and reliable reproducibility (5.5-9.5%). Graphical abstract Schematic representation of headspace-solid phase microextraction (HS-SPME) of phthalate esters (PhEs) from pickled cucumber solution and determination with gas chromatography-mass spectrometry (GC-MS).
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http://dx.doi.org/10.1007/s00604-020-4224-9DOI Listing
April 2020

On-disc electromembrane extraction-dispersive liquid-liquid microextraction: A fast and effective method for extraction and determination of ionic target analytes from complex biofluids by GC/MS.

Anal Chim Acta 2020 Apr 15;1105:95-104. Epub 2020 Jan 15.

Department of Chemistry, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran. Electronic address:

In this study, an electromembrane extraction-dispersive liquid-liquid microextraction (EME-DLLME) was performed using a lab-on-a-disc device. It was used for sample microextraction, preconcentration, and quantitative determination of tricyclic antidepressants as model analytes in biofluids. The disc consisted of six extraction units for six parallel extractions. First, 100 μL of a biofluid was used to extract the analytes by the drop-to-drop EME to clean-up the sample. The extraction then was followed by applying the DLLME method to preconcentrate the analytes and make them ready for being analyzed by gas chromatography (GC). Implementing the EME-DLLME method on a chip device brought some significant advantages over the conventional methods, including saving space, cost, and materials as well as low sample and energy consumption. In the designed device, centrifugal force was used to move the fluids in the disc. Both sample preparation methods were performed on the same disc without manual transference of the donor phases for doing the two methods. Scalable centrifugal force made it possible to adjust the injection speed of the organic solvent into the aqueous solution in the DLLME step by changing the spin speed. Spin speed of 100 rpm was used in dispersion step and spin speed of 3500 rpm was used to sediment organic phase in DLLME step. The proposed device provides effective and reproducible extraction using a low volume of the sample solution. After optimization of the effective parameters, an EME-DLLME followed by GC-MS was performed for determination of amitriptyline and imipramine in saliva, urine, and blood plasma samples. The method provides extraction recoveries and preconcentration factors in the range of 43%-70.8% and 21.5-35.5 respectively. The detection limits less than 0.5 μg L with the relative standard deviations of the analysis which were found in the range of 1.9%-3.5% (n = 5). The method is suitable for drug monitoring and analyzing biofluids containing low levels of the model analytes.
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http://dx.doi.org/10.1016/j.aca.2020.01.024DOI Listing
April 2020

3D Printing in analytical sample preparation.

J Sep Sci 2020 May 16;43(9-10):1854-1866. Epub 2020 Mar 16.

Australian Centre for Research on Separation Science (ACROSS), School of Natural Sciences. Chemistry, University of Tasmania, Hobart, Tasmania, Australia.

In the last 5 years, additive manufacturing (three-dimensional printing) has emerged as a highly valuable technology to advance the field of analytical sample preparation. Three-dimensional printing enabled the cost-effective and rapid fabrication of devices for sample preparation, especially in flow-based mode, opening new possibilities for the development of automated analytical methods. Recent advances involve membrane-based three-dimensional printed separation devices fabricated by print-pause-print and multi-material three-dimensional printing, or improved three-dimensional printed holders for solid-phase extraction containing sorbent bead packings, extraction disks, fibers, and magnetic particles. Other recent developments rely on the direct three-dimensional printing of extraction sorbents, the functionalization of commercial three-dimensional printable resins, or the coating of three-dimensional printed devices with functional micro/nanomaterials. In addition, improved devices for liquid-liquid extraction such as extraction chambers, or phase separators are opening new possibilities for analytical method development combined with high-performance liquid chromatography. The present review outlines the current state-of-the-art of three-dimensional printing in analytical sample preparation.
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http://dx.doi.org/10.1002/jssc.202000035DOI Listing
May 2020

Accordion-like TiCT MXene nanosheets as a high-performance solid phase microextraction adsorbent for determination of polycyclic aromatic hydrocarbons using GC-MS.

Mikrochim Acta 2020 01 29;187(2):151. Epub 2020 Jan 29.

Department of Chemistry, Tarbiat Modares University, P. O. Box 14115-175, Tehran, 1411713116, Iran.

Two dimensional accordion-like TiCT MXene, where T represents surface termination groups such as -OH, -O-, and -F, is synthesized by selective etching of aluminum layers from TiAlC. This manuscript reports on the adsorption of organic molecules from head-space and aqueous environments containing TiCT, a representative of the MXene family. TiCT coated by gluing method on a stainless steel wire was successfully utilized as a highly sensitive and stable head-space solid-phase microextraction (SPME) fiber. A SPME method with the MXene as the adsorbent combined with gas chromatography with MS detector was used to determine the polycyclic aromatic hydrocarbons (PAHs) in water samples. Low detection limits in the range of 0.2-5 ng L, wide linearity and good reproducibility (RSD = 4.6 to 7.4% for n = 6) under the optimized extraction conditions was achieved. Finally, the MXene coated fiber was successfully used for the determination of PAHs in real water samples. The relative recoveries for six PAHs are from 91.3-105.0%, which proved the applicability of the method. Also, melamine was selected as a polar analyte and it has been shown that TiCT MXene has good capability in extraction of melamine (the extraction recovery for melamine = 80.1%) from aqueous media by dispersive micro solid-phase extraction. Graphical abstractTwo dimensional accordion-like TiC MXene was synthesized by selective etching of aluminum layers from TiAlC. TiC MXene was employed as solid phase microextraction fiber coating for the extraction of polycyclic aromatic hydrocarbons from water samples.
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http://dx.doi.org/10.1007/s00604-020-4123-0DOI Listing
January 2020

An electrodeposited terephthalic acid-layered double hydroxide (Cu-Cr) nanosheet coating for in-tube solid-phase microextraction of phthalate esters.

Mikrochim Acta 2020 01 10;187(2):118. Epub 2020 Jan 10.

Department of Chemistry, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran.

A CuCr-layered double hydroxide nanosheet intercalated with terephthalic acid (TPA/LDH) was introduced as a coating for the in-tube solid phase microextraction (IT-SPME). The coating was placed on the inner surface of a stainless steel tube by using two-electrode electrodeposition. The sorbent was characterized by X-ray diffraction, scanning electronic microscopy, and Fourier transform infrared spectroscopy. The TPA/LDH coating, compared to a nitrate-LDH coating, exhibits enhanced extraction efficiency, long lifetime, good mechanical stability, and a large specific surface. The method was used for the extraction, preconcentration, and subsequent HPLC-based determination of dimethyl phthalate (DMP), dibutyl phthalate (DBP), diallyl phthalate (DAP), and diethylhexyl phthalate (DEHP). The effects of pH value of the solution, salt concentration, extraction and desorption conditions, and the effect of the alcohol content of the solution on the extraction efficiency were optimized. Under optimal conditions, the response is linear in the 0.05 to 1000 μg L ester concentration range, and the limits of detection (at S/N = 3) range between 0.01 to 0.1 μg L. The inter- and intra-assay precisions (RSD%, for n = 3) range from 3.8 to 6.8% and from 3.5 to 5.7%, respectively. The method was successfully applied to the determination of four phthalate esters in different beverage samples. Graphical abstractA CuCr-layered double hydroxide nanosheet intercalated with terephthalic acid was used as a coating for in-tube solid phase microextraction of some phthalate esters from beverage samples.
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http://dx.doi.org/10.1007/s00604-019-4102-5DOI Listing
January 2020

Developing a novel packed in-tube solid-phase extraction method for determination 9-tetrahydrocannabinol in biological samples and cannabis leaves.

J Sep Sci 2020 Mar 9;43(6):1128-1136. Epub 2020 Jan 9.

Department of Chemistry, Tarbiat Modares University, Tehran, Iran.

A novel plate-like nano-sorbent based on copper/cobalt/chromium layered double hydroxide was synthesized by a simple coprecipitation method. The synthesized nanoparticels were introduced into a stainless steel cartridge using a dry packing method. Then, the packed cartridge was introduced as a novel on-line "packed in-tube" configuration and followed by high performance liquid chromatography for the determination of trace amounts of 9-tetrahydrocannabinol from biological samples and cannabis leaves. The as-prepared sorbent exhibited long lifetime, good chemical stability, and high anion-exchange capacity. Several important factors affecting the extraction efficiency, such as extraction and desorption times, pH of the sample solution and flow rates of the sample and eluent solutions, were investigated and optimized. Under optimized conditions, this method showed good linearity for 9-tetrahydrocannabinol in the ranges of 0.09-500, 0.3-500, and 0.4-500 µg/L with coefficients of determination of 0.9999, 0.9991, and 0.9994 in water, serum and plasma samples, respectively. The inter- and intra-assay precisions (n = 3) were respectively in the ranges of 1.8-4.6% and 1.9-4.0% at three concentration levels of 10, 50, and 100 µg/L. The limits of detection were also in the range of 0.02-0.1 µg/L.
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http://dx.doi.org/10.1002/jssc.201900965DOI Listing
March 2020

On-chip ion pair-based dispersive liquid-liquid extraction for quantitative determination of histamine H receptor antagonist drugs in human urine.

Talanta 2020 Jan 8;206:120235. Epub 2019 Aug 8.

Reference Laboratory, Health Deputy, Iran University of Medical Siences, Tehran, Iran.

In the present work, an ion-pair based dispersive liquid-liquid microextraction was performed on a centrifugal chip for the first time. The entire DLLME procedure, including flow direction, desperation, and sedimentation of the extracting phase, can be fulfilled automatically on a solitary chip. The chip was made of Poly(methyl methacrylate) (PMMA) and was of two units for two parallel extractions, each consisting of three chambers (for the sample solution, extracting solvents, and sedimentation). As the chip rotated, fluids flowed within the chip, and the dispersion, mixing, extraction, and sedimentation of the final phase were performed on the chip by simply adjusting the spin speed. Determination of two histamine H receptor antagonist drugs, cimetidine and ranitidine, as the model analytes from the urine samples was done using the developed on-chip ion-pair based DLLME method followed by an HPLC-UV. The effective parameters on the extraction efficiency of the model analytes were investigated and optimized using the one variable at a time method. Under optimized conditions, the calibration curve was linear in the range of 15-2000 μg L with a coefficient of determination (R) more than 0.9987. The relative standard deviations (RSD %) for extraction and determination of the analytes were less than 3.7% based on five replicated measurements. LODs less than 10.0 μg L and preconcentration factors higher than 39-fold were obtained for both of the model analytes. The proposed chip enjoys the advantages of both the DLLME method and miniaturization on a centrifugal chip.
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http://dx.doi.org/10.1016/j.talanta.2019.120235DOI Listing
January 2020

Carbon fibers modified with polypyrrole for headspace solid phase microextraction of trace amounts of 2-pentyl furan from breath samples.

J Chromatogr A 2020 Jan 29;1609:460497. Epub 2019 Aug 29.

Department of Chemistry, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran.

This study introduces micrometric carbon strands as a suitable fiber for headspace solid phase microextraction. Compared to previous supports, carbon fibers have mechanical flexibility, wide thermal expansion, and a large surface area, which is an important factor in headspace solid phase microextraction. The electrophoretic technique was applied to modify the surface of stainless steel and carbon fibers with polypyrrole. Modified carbon fibers were used for extraction of 2-pentylfuran (2-PF) as a model analyte from patients' breath and coffee samples. 2-PF belongs to the furan family, which was suggested as a biomarker for Aspergillus fumigatus and was classified as a possible carcinogen. 2-PF can be found in many heat-processed foods and drinks. The separation and detection of the analyte was performed by gas chromatography coupled to mass spectrometry. The effective factors in the extraction performance of the analyte by carbon fiber supports were investigated and optimized. Under optimized extraction conditions (temperature, 20 °C; time, 15 min; desorption temperature, 200 °C; desorption time, 2 min; salt concentration, 10% w/v; and stirring rate, 700 rpm), the limit of detection was calculated as 0.05 ng mL, whereas repeatability and fiber-to-fiber reproducibility (RSD %) was found to be in the range of 3.2-4.1%. The experimental results showed that the proposed fiber had greater extraction performance for 2-pentylfuran.
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http://dx.doi.org/10.1016/j.chroma.2019.460497DOI Listing
January 2020

Microextraction on a screw.

Anal Chim Acta 2019 Nov 2;1083:130-136. Epub 2019 Aug 2.

Chemistry & Chemical Engineering Research Center of Iran, P.O. Box 14334-186, Tehran, Iran.

For the first time, a rapid, efficient, simple, and inexpensive approach for solid phase microextraction on a screw (MES) was developed. MES is a miniaturized form of solid-phase extraction without any backpressure. In this system, analytes were adsorbed on the surface of micro channels of a screw that was coated by polypyrrole (PPy). Based on this procedure, the analytes are adsorbed on the solid phase and then eluted by a desorption solvent. The MES method followed by gas chromatography-mass spectrometry (MES-GC-MS) was applied for the rapid extraction and determination of six polycyclic aromatic hydrocarbons (PAHs) (as model analytes) in well water samples. Several parameters affecting the extraction procedure, including the sampling flow rate, the number of the loading/desorption cycles of the sample, and the volume of the desorption solvent, were evaluated and optimized. Under optimum conditions, the detection limits for the PAHs varied between 0.5 and 1 μg L and linear ranges varied between 2 and 600 μg L. The results showed good correlation coefficients (R > 0.99) for all of the analytes in the studied calibration range. The relative recovery (RR%) of the desired MES-GC-MS method for the studied PAHs was between 83.0 and 104.0% and the interday and intraday precision (n = 5 days), expressed as relative standard deviation (RSD %), were between 3.9-6.2% and 6.2-8.9%, respectively. To evaluate the matrix effect, the developed method was also applied for preconcentration and determination of the selected PAHs in real water samples, and good results were obtained.
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http://dx.doi.org/10.1016/j.aca.2019.07.069DOI Listing
November 2019

Chitosan-based sorbent for efficient removal and extraction of ciprofloxacin and norfloxacin from aqueous solutions.

Mikrochim Acta 2019 06 20;186(7):459. Epub 2019 Jun 20.

Department of Chemistry, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran.

Nanosheets prepared from magnesium oxide, chitosan and graphene oxide (MgO/Chit/GO) were hydrothermally synthesized and used as a sorbent for removal of ciprofloxacin and norfloxacin from aqueous solutions. Residual antibiotics in sample were determined by HPLC/UV instrument. The sorbent was characterized by FTIR, XRD, BET, SEM, and TEM. Its high adsorption capacity is attributed to the high surface area (294 m.g) as compared to bare MgO/chit or bare GO. The pore size of the mesoporous sorbent typically is 15 Å. The adsorption isotherms for the two model antibiotics studied (norfloxacin, ciprofloxacin) can be described with the Langmuir model, and the maximum adsorption capacities are 1111 and 1000 mg.g for ciprofloxacin and norfloxacin, respectively. The analysis of the kinetic data revealed that the synthesized sorbent followed pseudo-second-order kinetics and the maximum equilibrium was at over 120 and 150 min for ciprofloxacin and norfloxacin, respectively. Therefore, it is introduced as an economical, eco- friendly, and high-performance sorbent for removal of antibiotics from aqueous solutions. Graphical abstract Schematic presentation of dispersion of magnesium oxide/chitosan/graphene oxide (MgO/chit/GO) nanosheets in waste water for removal of ciprofloxacin and norfloxacin as water pollutants.
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http://dx.doi.org/10.1007/s00604-019-3563-xDOI Listing
June 2019

Imidazolium-based mesoporous organosilicas with bridging organic groups for microextraction by packed sorbent of phenoxy acid herbicides, polycyclic aromatic hydrocarbons and chlorophenols.

Mikrochim Acta 2019 03 13;186(4):239. Epub 2019 Mar 13.

Department of Anatomy and Cell Biology and Facility for Electron Microscopy Research, McGill University, Montreal, Quebec, H3A2A7, Canada.

The authors describe the preparation of two kinds of periodic mesoporous organosilicas (PMOs). The first kind is monofunctional and has a bridged alkyl imidazolium framework (PMO-IL). The other is a two-dimensional (2D) hexagonal bifunctional periodic mesoporous organosilica (BFPMO) with bridged IL-phenyl or -ethyl units. The CPMOs were utilized as highly sensitive and stable sorbents for microextraction by packed sorbent. The materials were characterized by SEM, TEM, FT-IR, and N adsorption-desorption analysis. The adsorption capacities of the sorbents were investigated by using phenoxy acid herbicides as model analytes. The effects of bifunctionality and type of additional surface groups (phenyl or ethyl) on the efficiency of the extraction is emphasized. Three kinds of environmental contaminants, viz. phenoxy acid herbicides (CPAs), polycyclic aromatic hydrocarbons and chlorophenols were then studied with respect to their extraction by the sorbents. The interactions between the CPAs and the sorbents were evaluated by pH-changing processes to explore the interactions that play a major role. The selectivity of the sorbents was investigated by extraction of other types of analytes of with various polarity and charge. The BFPMOs display the typical good chemical stability of silica materials. The extraction properties are much better compared to commercial silicas. This is assumed to be due to the highly ordered mesoporous structures and the different types of probable interactions with analytes. The performance of the method was evaluated by extraction of CPAs as model analytes from aqueous samples, and quantification by GC with FID detection. Under optimized conditions, low limits of detection (0.1-0.5 μg.L) and a wide linearity (0.5-200 μg.L) were obtained. The method was applied to the trace analysis of CPAs in farm waters and rice samples. Graphical abstract Monofunctional periodic mesoporous organosilica with bridged alkyl imidazolium frameworks and bi-functional periodic mesoporous organosilica containing bridged ionic liquids and phenyl or -ethyl, have been successfully synthesized and utilized in microextractions by packed sorbent sorbents.
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http://dx.doi.org/10.1007/s00604-019-3355-3DOI Listing
March 2019

Extraction of antidepressant drugs in biological samples using alkanol-based nano structured supramolecular solvent microextraction followed by gas chromatography with mass spectrometric analysis.

J Sep Sci 2019 Apr 27;42(8):1620-1628. Epub 2019 Feb 27.

Department of Chemistry, Faculty of Sciences, Tarbiat Modares University, Tehran, Iran.

In the present study, a supramolecular solvent was formed from reverse micelle aggregates of octanol. The proposed supramolecular solvent was used for rapid extraction of some antidepressants drugs including amitriptyline, imipramine, desipramine, maprotiline, sertraline, and doxepin from biological samples. Alkanol-based supramolecular solvents have a unique array of physicochemical properties, making them a very attractive alternative to replace organic solvents in analytical extractions. The parameters affecting the extraction of target analytes (i.e., the volume of tetrahydrofuran and octanol as the major components comprising the supramolecular solvent, chain length of alkanols, sample solution pH, salt addition, and ultrasonic time) were investigated and optimized by factor by factor optimization method. Under the optimum conditions, preconcentration factors of 470, 490, 460, 385, 370, and 430 were obtained for amitriptyline, doxepin, imipramine, desipramine, maprotiline, and sertraline, respectively. The linear ranges and coefficients of determination (R ) were obtained in the range of 0.01-100 μg/L and 0.9974-0.9991, respectively. Also the limits of detection (S/N = 3) of 0.003-0.03 μg/L, and precisions (n = 5) of 4.9-8.9% were calculated. Finally, the method was successfully applied for the extraction of antidepressant drugs in biological samples, and relative recoveries in the range of 91-102% were obtained.
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http://dx.doi.org/10.1002/jssc.201801152DOI Listing
April 2019

Synthesis and characterization of a novel biocompatible pseudo-hexagonal NaCa-layered double metal hydroxides for smart pH-responsive drug release of dacarbazine and enhanced anticancer activity in malignant melanoma.

Mater Sci Eng C Mater Biol Appl 2019 Apr 7;97:96-102. Epub 2018 Dec 7.

Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran.

Layered metal hydroxides have exhibited remarkable benefits in drug delivery, days or even weeks of continuous drug release with improved bioavailability and minimized adverse effects. Here, we report synthesis of a new M (Na) and M (Ca) layered double metal hydroxide-based phases with the general formula of [NaCa(OH)] (NO), and 3D pseudo-hexagonal morphology. NaCa layered double metal hydroxide (NaCa-LDH), which is biodegradable, biocompatible, and pH-sensitive, could have broad applicability in drug release and other biomedical applications. Dacarbazine (DAC) is one of the most commonly used chemotherapy drugs for treating various cancers. However, its poor water solubility, short half-life in blood circulation, low response rate and high side effects limit its application. This study aimed to increase its half-life and anticancer activity; minimize its side effects; and prolong its drug release by intercalating of DAC in biodegradable NaCa-LDH (DAC-LDH). Results from the intercalation process show that NaCa-LDH is able to intercalate DAC with a simple procedure and with a good drug loading (38% w/w) through a one pot reaction. The DAC shows a sustained and pH-sensitive release, and the release rate of DAC from DAC-LDH at pH 7.4 is remarkably lower than that at pH 6.0 due to its different release mechanisms. In the latter case, the release was not complete at 24 h. We show that DAC-LDH anticancer efficacy on malignant (A-375) melanoma and breast cancer (MCF-7) cell lines is higher than that of free DAC. These nanoparticles may open a significant way toward the development of a pH-sensitive drug release system that minimizes drug side effect for a wide range of applications.
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http://dx.doi.org/10.1016/j.msec.2018.12.017DOI Listing
April 2019

Simultaneous extraction of acidic and basic drugs via on-chip electromembrane extraction using a single-compartment microfluidic device.

Analyst 2019 Feb;144(4):1159-1166

Department of Chemistry, Faculty of Sciences, Tarbiat Modares University, P.O. Box: 14115-175, Tehran, Iran.

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. The middle part was cut and an "M" pattern provided interfaces for contact between the sample solution flow and two porous polypropylene sheets on both sides. Two other parts had the same spiral channels dedicated to the corresponding acceptor phases of the acidic and basic analytes and were located at both sides. Each polypropylene sheet was impregnated with the appropriate organic solvent for the acidic and basic analytes. Two platinum electrodes connected to a power supply were mounted at the bottom of the acceptor channels. These electrodes provided the electrical fields across SLMs to extract the analytes from a single sample flow. When the extraction was completed, the acceptor solutions were collected, mixed, and then injected into the chromatographic system. The effective parameters on the extraction efficiency were investigated and optimized. Under the optimal conditions, the calibration curves were linear in the range of 9.0-500 μg L-1 for NAL and 11.0-500 μg L-1 for DIC with the coefficient of determination (R2) higher than 0.9913. The relative standard deviations (RSD%) based on five replicate measurements were less than 6.3%. LOD values were 4.0 and 3.0 μg L-1 for DIC and NAL, respectively. Finally, the method was successfully applied to determine DIC and NAL in the human urine samples and satisfactory results were obtained (recovery ≥90).
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http://dx.doi.org/10.1039/c8an01668bDOI Listing
February 2019
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