Iranian Research and Development Center for Chemical Industries

Tehrān, Iran

Iranian Research and Development Center for Chemical Industries

Tehrān, Iran
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Sobhi H.R.,Payame Noor University | Ghambarian M.,Iranian Research and Development Center for Chemical Industries | Behbahani M.,Kermanshah University of Medical Sciences | Esrafili A.,Iran University of Science and Technology | Esrafili A.,Tehran University of Medical Sciences
Journal of Chromatography A | Year: 2017

Herein, a simple and sensitive method was successfully developed for the extraction and quantification of acrylamide in water samples. Initially, acrylamide was derivatized through a bromination process. Subsequently, a modified hollow-fiber liquid-phase microextraction was applied for the extraction of the brominated acrylamide from a 10-ml portion of an aqueous sample. Briefly, in this method, the derivatized acrylamide (2,3-dibromopropionamide) was extracted from the aqueous sample into a thin layer of an organic solvent sustained in pores of a porous hollow fiber. Then, it was back-extracted using a small volume of organic acceptor solution (acetonitril, 25μl) located inside the lumen of the hollow fiber followed by gas chromatography-electron capture detection (GC-ECD). The optimal conditions were examined for the extraction of the analyte such as: the organic solvent: dihexyl ether+10% tri-n-octyl phosphine oxide; stirring rate: 750rpm; no salt addition and 30min extraction time. These optimal extraction conditions allowed excellent enrichment factor values for the method. Enrichment factor, detection limit (S/N=3) and dynamic linear range of 60, 2ngL-1 and 50-1000ngL-1 to be determined for the analyte. The relative standard deviations (RSD%) representing precision of the method were in the range of 2.2-5.8 based on the average of three measurements. Accuracy of the method was tested by the relative recovery experiments on spiked samples, with results ranging from 93 to 108%. Finally, the method proved to be simple, rapid, and cost-effective for routine screen of acrylamide-contaminated highly-complicated untreated waste water samples. © 2017 Elsevier B.V.


Torkian L.,Islamic Azad University at South Tehran | Amini M.M.,Shahid Beheshti University | Amereh E.,Iranian Research and Development Center for Chemical Industries
Materials Technology | Year: 2013

Silver doped TiO2 nanocomposite [1% (w/w)] and undoped nano-TiO2 particles were prepared by sol-gel method from tetraporopyl orthotitanate as the precursor. To improve the photocatalytic efficiency, silver doped TiO2 nanoparticles were immobilised on NaX zeolite and used as photocatalyst. Chemical composition and optical absorption of the photocatalyst were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), infrared and ultraviolet-visible absorption spectroscopy. The XRD patterns show that the supported TiO2 are crystallised in anatase phase, and the intensity of the zeolite peaks decreases with the increase in TiO2 loading. Characterisation of samples by SEM indicates that the outer surface of the zeolite crystals is covered by the titania particles. Infrared spectroscopy revealed that the nanosize titanium oxide particles are linked to the framework through Ti-O-Si bonds. Ultraviolet-visible diffuse reflectance spectrum of metal doped TiO2 nanocomposite shows red shift in the band gap transition. The photocatalytic performances of these composite semiconductors were examined with respect to an azo dye, Orange G. The effects of pH and irradiation time on photodegradation were investigated. According to the UV-vis absorption spectroscopy results, the photodegradation of orange G dye under UV light irradiation in the presence of silver doped TiO2/NaX zeolite catalyst is more efficient than the Ag/TiO 2 nanocomposite and also undoped nanotitanium oxide powder. © 2013 W. S. Maney & Son Ltd.


Ghambarian M.,Iranian Research and Development Center for Chemical Industries | Yamini Y.,Tarbiat Modares University | Esrafili A.,Tehran University of Medical Sciences
Microchimica Acta | Year: 2013

Microextraction of organic or inorganic analytes using solidified floating drops of organic solvents is a fairly new method that is simple and rapid, and requires only small quantities of solvents and reagents. This review (with 109 references) covers published work up to Sep. 2012, and describes how the method was combined with analytical techniques such as GC, HPLC, ICP-OES and electrothermal atomic absorption spectrometry. We discuss basic principles and the main parameters that affect the extraction efficiency, and give specific applications of the technique. © 2013 Springer-Verlag Wien.


Esrafili A.,Tarbiat Modares University | Esrafili A.,Tehran University of Medical Sciences | Yamini Y.,Tarbiat Modares University | Ghambarian M.,Iranian Research and Development Center for Chemical Industries | Ebrahimpour B.,Tarbiat Modares University
Journal of Chromatography A | Year: 2012

The present work describes the first automated instrument, based on on-line hollow fiber liquid-phase microextraction (HF-LPME)-high performance liquid chromatography (HPLC), for the preconcentration and determination of organic compounds in various matrices. Using an automated syringe pump for loading the supported liquid membrane and acceptor solvents, a platform lift for moving the sample vial, a sampling loop for on-line injection of the extract to HPLC, along with an electronic board with an AVR microcontroller for storage of data and instrument programs, a sample preparation-HPLC method was developed that allowed sample extraction and extract injection to be carried out completely automatically. Pyridine and pyridine derivatives were chosen for the development and for testing the applicability of the automated instrument. The limits of detection (3 times the S/N) ranged from 0.5 to 1.0μgL-1. Effective preconcentration of the analytes was also achieved (preconcentration factors of between 40 and 220). The main advantages of the method developed are minimum sample manipulation, full automation, suitable extraction time, low solvent consumption, and ease of use. The applicability of the on-line automated HF-LPME/HPLC-UV instrument was validated for quantitative extraction and determination of pyridines in cigarette smoke. © 2012 Elsevier B.V.


Ghambarian M.,Tarbiat Modares University | Yamini Y.,Tarbiat Modares University | Esrafili A.,Tarbiat Modares University | Yazdanfar N.,Iranian Research and Development Center for Chemical Industries | Moradi M.,Tarbiat Modares University
Journal of Chromatography A | Year: 2010

A new concept of liquid-liquid-liquid microextraction (LLLME) was introduced based on applying two immiscible organic solvents in lumen and wall pores of hollow fiber (HF). With this methodology, analytes of interest can be extracted from aqueous sample, into a thin layer of organic solvent (dodecane) sustained in the pores of a porous hollow fiber, and further into a μL volume of organic acceptor (acetonitrile or methanol) located inside the lumen of the hollow fiber. Some chlorophenols (CPs) were selected as model compounds for developing and evaluating of the method performance. The analysis was performed by gas chromatography-electron capture detection (GC-ECD) without derivatization. The factors affecting the HF-LLLME of target compounds were investigated and the optimal extraction conditions were established. Under the optimum conditions, preconcentration factors in a range of 208-895 were obtained. The performance of the proposed method was studied in terms of linear dynamic ranges (LDRs from 0.02 to 100ngmL-1), linearity (R2≥0.995), precision (RSD %≤8.1) and limits of detection (LODs in the range of 0.006-0.2ngmL-1). In addition to preconcentration, HF-LLLME also served as a technique for sample clean-up. © 2010 Elsevier B.V.


Ghambarian M.,Tarbiat Modares University | Khalili-Zanjani M.R.,Tarbiat Modares University | Yamini Y.,Tarbiat Modares University | Esrafili A.,Tarbiat Modares University | Yazdanfar N.,Iranian Research and Development Center for Chemical Industries
Talanta | Year: 2010

A simple solidification of floating drop microextraction procedure for preconcentration and speciation of trace amounts of As(III) and As(V) in water samples has been proposed prior to electrothermal atomic absorption spectrometry (ETAAS). In this method, a free microdroplet of organic solvent is floated on the surface of aqueous solution while being agitated by a stirring bar placed on the bottom of the sample vial. The determination of As(III) was achieved by selective formation of the As(III)-pyrrolidine dithiocarbamate complex in the presence of 0.1 M HCl while As(V) forms a weak complex with the ligand in the same pH conditions. Total inorganic As(III, V) was extracted similarly after reduction of As(V) to As(III) with potassium iodide and sodium thiosulfate and As(V) concentration was calculated by difference. Pd(NO3)2 was used as a chemical modifier in ETAAS. Some important extraction parameters such as the type of organic solvent, solvent volume, sample stirring rate, sample solution temperature, salt addition and the exposure time on the extraction recovery were investigated and optimized. Under the optimized extraction conditions, the detection limit of 9.2 pg mL-1 and suitable precision (RSD < 8.6%), along with enhancement factor of 1000 for As were achieved. The developed method was applied successfully to speciation of As(III), As(V) and determination of the total amount of As in water samples. © 2009 Elsevier B.V. All rights reserved.


Ghambarian M.,Iranian Research and Development Center for Chemical Industries | Yamini Y.,Tarbiat Modares University | Esrafili A.,Tarbiat Modares University
Microchimica Acta | Year: 2012

Hollow fiber liquid-phase microextraction (HF-LPME) offers an efficient alternative to classical techniques for sample preparation and preconcentration. Features include high selectivity, good enrichment factors, and improved possibilities for automation. HP-LPME relies on the extraction of target analytes from aqueous samples into a supported liquid membrane (SLM) sustained in the pores of the wall of a porous hollow fiber, and then into an acceptor phase (that can be aqueous or organic) in the lumen of the hollow fiber. After extraction, the acceptor solution is directly subjected to a chemical analysis. HP-LPME can be performed in either the 2- or 3-phases mode. In the 2-phase mode, the organic solvent is present both in the porous wall and inside the lumen of the hollow fiber. In the 3-phase mode, the acceptor phase can be aqueous and this results in a conventional 3-phase system compatible with HPLC or capillary electrophoresis. Alternatively, the acceptor solution is organic and this represents a 3-phase extraction system with two immiscible organic solvents that is compatible with all common analytical instruments. In HP-LPME methods based on the use of SLMs, the mass transfer occurs by passive diffusion, and high extraction yields as well as efficient extraction kinetics are obtained by applying a pH gradient. In addition, active transport can be performed by using carrier or applying an electrical potential across the SLM. Due to high analyte preconcentration, excellent sample clean-up, and low consumption of organic solvent, HF-LPME has a large application potential in areas such as drug analysis and environmental monitoring. This review focuses on the fundamentals of extraction principles, technical implementations, and future trends in HF-LPME. © 2012 Springer-Verlag.


Tajabadi F.,Iranian Research and Development Center for Chemical Industries | Ghambarian M.,Iranian Research and Development Center for Chemical Industries | Yamini Y.,Tarbiat Modares University | Yazdanfar N.,Iranian Research and Development Center for Chemical Industries
Talanta | Year: 2016

In the present research, a carrier mediated hollow fiber based liquid-phase microextraction approach (HF-LPME) prior to high performance liquid chromatography-diode array detection (HPLC-DAD) was developed for the simultaneous determination of the antibacterial residues of four tetracyclines (TCs) and five quinolones (QNs), which are commonly used as veterinary medicines. In order to obtain high extraction efficiency, the parameters affecting HF-LPME were optimized using a three-factor and three-level Box-Behnken design under response surface methodology. This method was validated according to the recommendations of the Food and Drug Administration (FDA), and, for the first time, successfully applied to a wide range of animal source food samples such as fish, milk, and honey as well as the liver and muscles of lamb and chicken. Analytical performance was determined in terms of linearity, intra- and inter-assay precision, detection and quantification limits, matrix effect, accuracy, and drug stability in real samples. Detection and quantitation limits for the different antibiotics ranged between 0.5–20 ng g−1 and 1.25–40 ng g−1, respectively. Intra and inter-day repeatability, expressed as the relative standard deviation, were in the ranges of 3.4–10.7% and 5.0–11.5%, respectively. The procedure allows good preconcentration factors of 175–700. The results of the validation process proved that the method is suitable for determining TCs and QNs residues in surveillance programs. Finally, the applicability of the proposed method was successfully confirmed by the extraction and determination of nine antibiotics in various animal source food samples. The importance of this methodology relies on the combination of HF-LPME/HPLC-DAD second-order data with multivariate curve resolution-alternative least squares (MCR-ALS) algorithm, which improves the resolution of some overlapped chromatograms and, hence, increases the accuracy and repeatability of drug determination. © 2016 Elsevier B.V.


Shamsipur M.,Razi University | Yazdanfar N.,Razi University | Ghambarian M.,Iranian Research and Development Center for Chemical Industries
Food Chemistry | Year: 2016

In this work, an effective preconcentration method for the extraction and determination of traces of multi-residue pesticides was developed using solid-phase extraction (SPE) coupled with dispersive liquid-liquid microextraction and gas chromatography-mass spectrometry (GC-MS). Variables affecting the performance of both extraction steps such as type and volume of elution and extraction solvents, breakthrough volume, salt addition, extraction time were thoroughly investigated. The proposed method resulted in good linearities (R2 > 0.9915) over the ranges of 1-10,000 ng kg-1, limits of detection (LODs) in the range of 0.5-1.0 ng kg-1 at S/N = 3, and precision of RSD% of ≤11.8. Under optimal conditions, the preconcentration factors were obtained in the range of 2362-10,593 for 100 mL sample solutions. Comparison of the proposed method with other ones demonstrated that SPE-DLLME method provides higher extraction efficiency and larger preconcentration factor for determination of pesticides residues. Further, it is simple, inexpensive, highly sensitive, and can be successfully applied to separation, preconcentration and determination of the pesticides (and other noxious materials) in different real food samples. © 2016 Elsevier Ltd. All rights reserved.


Leila T.,Islamic Azad University at South Tehran | Ehsan A.,Iranian Research and Development Center for Chemical Industries
Research Journal of Chemistry and Environment | Year: 2011

Malachite green, a triarylmethane dye, is a water pollutant and conventionally used for materials such as silk, leather and paper. Traditional degradation methods are commonly non destructive and reduce the dye to potentially hazardous aromatic amines. In this work malachite green was degraded photo-catalytically under ultraviolet irradiation using untreated anatase T1O2 nano-particles. Titanium dioxide nano-crystals were prepared via a simple sol-gel process using inorganic precursor and characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The photoreaction was followed by monitoring the degradation of the dye as a function of UV irradiation time, in the presence of the nano photo-catalyst. It has been found that the dye adsorbs on the semiconductor nano-particles and undergoes a series of degradation processes which lead to complete decolorization after 240 min UV irradiation time. The decolorization activity of the prepared photo catalyst was characterized by UV-Vis absorption spectroscopy. For the purpose of comparison the photo-catalytic degradation of Malachite Green was performed by applying the commercial nano T1O2 (Degussa P-25).

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