Publications by authors named "Parviz Aberoomand Azar"

25 Publications

  • Page 1 of 1

A DNA Based Biosensor Amplified With ZIF-8/Ionic Liquid Composite for Determination of Mitoxantrone Anticancer Drug: An Experimental/Docking Investigation.

Front Chem 2020 20;8:814. Epub 2020 Oct 20.

Center for Nanotechnology in Drug Delivery, School of Pharmacy, Shiraz University of Medical Sciences, Shiraz, Iran.

An ultrasensitive DNA electrochemical biosensor based on the carbon paste electrode (CPE) amplified with ZIF-8 and 1-butyl-3-methylimidazolium methanesulfonate (BMIMS) was fabricated in this research. The DNA/BMIMS/ZIF-8/CPE was used for the selective determination of a mitoxantrone anticancer drug in aqueous solution, resulting in a good catalytic effect and a powerful ability for determining mitoxantrone. Also, the interaction of the mitoxantrone anticancer drug with guanine bases of ds-DNA was used as a powerful strategy in the suggested biosensor, which was confirmed with docking investigation. Docking study of mitoxantrone into the ds-DNA sequence showed the intercalative binding mode of mitoxantrone into the nitrogenous-based pairs of ds-DNA. The effective factors such as ds-DNA concentration, temperature, buffer types, and incubation time were also optimized for the fabricated mitoxantrone biosensor. The results showed that, under optimum conditions (T = 25°C; incubation time=12 min; pH= 4.8 acetate buffer solution and [DNA] = 50 mg/L), the DNA/BMIMS/ZIF-8/CPE could be used in mitoxantrone assay in a concentration ranging from 8.0 nM to 110 μM with a detection limit of 3.0 nM. In addition, recovery data between 99.18 and 102.08% were obtained for the determination of mitoxantrone in the injection samples using DNA/ZIF-8/BMIMF/CPE as powerful biosensors.
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http://dx.doi.org/10.3389/fchem.2020.00814DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7606923PMC
October 2020

Evaluation of Pt,Pd-Doped, NiO-Decorated, Single-Wall Carbon Nanotube-Ionic Liquid Carbon Paste Chemically Modified Electrode: An Ultrasensitive Anticancer Drug Sensor for the Determination of Daunorubicin in the Presence of Tamoxifen.

Front Chem 2020 19;8:677. Epub 2020 Aug 19.

Center for Nanotechnology in Drug Delivery, School of Pharmacy, Shiraz University of Medical Sciences, Shiraz, Iran.

Measuring the concentration of anticancer drugs in pharmacological and biological samples is a very useful solution to investigate the effectiveness of these drugs in the chemotherapy process. A Pt,Pd-doped, NiO-decorated SWCNTs (Pt,Pd-NiO/SWCNTs) nanocomposite was synthesized using a one-pot procedure and combining chemical precipitation and ultrasonic sonochemical methods and subsequently characterized by TEM and EDS analysis methods. The analyses results showed the high purity and good distribution of elements and the ~10-nm diameter of the Pt,Pd-NiO nanoparticle decorated on the surface of the SWCNTs with a diameter of about 20-30 nm. Using a combination of Pt,Pd-NiO/SWCNTs and 1-butyl-2,3-dimethylimidazolium tetrafluoroborate (1B23DTFB) in a carbon paste (CP) matrix, Pt,Pd-NiO/SWCNTs/1B23DTFB/CP was fabricated as a highly sensitive analytical tool for the electrochemical determination of daunorubicin in the concentration range of 0.008-350 μM with a detection limit of 3.0 nM. Compared to unmodified CP electrodes, the electro-oxidation process of daunorubicin has undergone significant improvements in current (about 9.8 times increasing in current) and potential (about 110 mV) decreasing in potential). It is noteworthy that the designed sensor can well measure daunorubicin in the presence of tamoxifen (two breast anticancer drugs with a ΔE = 315 mV. According to the real sample analysis data, the Pt,Pd-NiO/SWCNTs/1B23DTFB/CP has proved to be a promising methodology for the analysis and measuring of daunorubicin and tamoxifen in real (e.g., pharmaceutical) samples.
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http://dx.doi.org/10.3389/fchem.2020.00677DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7466574PMC
August 2020

Glucose Oxidase/Nano-ZnO/Thin Film Deposit FTO as an Innovative Clinical Transducer: A Sensitive Glucose Biosensor.

Front Chem 2020 15;8:503. Epub 2020 Jul 15.

Thin Layer and Nanotechnology Laboratory, Institute of Chemical Technology, Iranian Research Organization for Science and Technology (IROST), Tehran, Iran.

In the present research, a new biocompatible electrode is proposed as a rapid and direct glucose biosensing technique that improves on the deficiencies of fast clinical devices in laboratory investigations. Nano-ZnO (nanostructured zinc oxide) was sputtered by reactive direct current magnetron sputtering system on a precovered fluorinated tin oxide (FTO) conductive layer. Spin-coated polyvinyl alcohol (PVA) at optimized instrumental deposition conditions was applied to prepare the effective medium for glucose oxidase enzyme (GOx) covalent immobilization through cyanuric chloride (GOx/nano-ZnO/PVA/FTO). The electrochemical behavior of glucose on the fabricated GOx/nano-ZnO/PVA/FTO biosensor was investigated by - techniques. In addition, field emission scanning electron microscopy and electrochemical impedance spectroscopy were applied to assess the morphology of the modified electrode surface. The - results indicated good sensitivity for glucose detection (0.041 mA per mM) within 0.2-20 mM and the limit of detection was 2.0 μM. We believe that such biodevices have good potential for tracing a number of biocompounds in biological fluids along with excellent accuracy, selectivity, and precise analysis. The fast response time of the fabricated GOx/nano-ZnO/PVA/FTO biosensor (less than 3 s) could allow most types of real-time analysis.
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http://dx.doi.org/10.3389/fchem.2020.00503DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7374262PMC
July 2020

Magnetic solid phase extraction based on poly(β-cyclodextrin-ester) functionalized silica-coated magnetic nanoparticles (NPs) for simultaneous extraction of the malachite green and crystal violet from aqueous samples.

Environ Monit Assess 2020 Apr 3;192(5):262. Epub 2020 Apr 3.

Department of Chemistry, Science and Research Branch, Islamic Azad University, Tehran, Iran.

In this research, an efficient sorbent based on poly(β-cyclodextrin-ester)-functionalized silica-coated magnetic nanoparticles (MNPs-CDP) was prepared and used for magnetic solid-phase extraction of the malachite green (MG) and crystal violet (CV) from water samples prior to their determination by high-performance liquid chromatography-ultra violet detection (HPLC-UV). The synthesized nanoparticles were characterized by the field emission-scanning electron microscopy (FE-SEM) and Fourier transform infrared spectroscopy (FT-IR). Of course, the factors, which could influence the extraction efficiency like pH, sorbent amount, salt content, extraction time, desorption time, eluent type, and volume and sample volume, were optimized by response surface methodology. Then, for both of MG and CV, good linearity (0.1-200 μg L, r ≥ 0.99) was achieved under the optimized conditions. The limits of detection (LODs) and the limits of quantification (LOQs), for both of MG and CV, were 0.03 μg L and 0.1 μg L, respectively. Precision of the method expressed as the relative standard deviations (RSDs) at concentration level of 100 μg L was 5.6 and 4.2 for MG and CV, respectively. Ultimately, usability of proposed method was investigated by analysis of CV and MG in tap water, fish pond water, and the lake water, and the satisfactory recoveries were obtained in the range of 92-100.5%.
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http://dx.doi.org/10.1007/s10661-020-8185-6DOI Listing
April 2020

Experimental design in formulation optimization of vitamin K oxide-loaded nanoliposomes for skin delivery.

Int J Pharm 2020 Apr 11;579:119136. Epub 2020 Feb 11.

Department of Chemistry, Central Tehran Branch, IAU, Tehran, Iran. Electronic address:

Due to the vitamin K sensitizing potential, the oxidized-isoform of vitamin K (vitamin K oxide, VKO), has been recently used for treating laser-induced purpura and hyperpigmentation in cosmetics. The objective of this study was to formulate VKO in nanoliposomes by using Box-Behnken experimental design to obtain an optimized formula with higher efficiency. The ratio of phospholipid to cholesterol (PC/CHO ratio), VKO concentration and sonication time in low, medium, and high levels were independent variables, while the percent of VKO entrapment efficiency (EE%) and vesicle size were selected as dependent variables. Optimum desirability was identified and an optimized formulation was prepared, characterized, and selected for in vitro VKO release and ex vivo skin permeation. The PC/CHO ratio showed the greatest effect on both responses (P < 0.0001). This effect was positive on EE%, while a negative effect was shown on vesicle size. The optimized formulation showed controlled drug release of 79.2% through a silicon membrane, and achieved flux of 327.36 ± 22.1 μg/cm through human skin after 24 h. So, nanoliposomes were proven as a suitable drug delivery system for topical delivery of VKO.
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http://dx.doi.org/10.1016/j.ijpharm.2020.119136DOI Listing
April 2020

Synthesis of N-doped TiO/SiO/FeO magnetic nanocomposites as a novel purple LED illumination-driven photocatalyst for photocatalytic and photoelectrocatalytic degradation of naproxen: optimization and different scavenger agents study.

J Environ Sci Health A Tox Hazard Subst Environ Eng 2019 8;54(12):1254-1267. Epub 2019 Oct 8.

Department of Chemistry, Science and Research Branch, Islamic Azad University , Tehran , Iran.

N-doped TiO/SiO/FeO as a new magnetic photocatalyst that is active in visible light has been prepared by simple sol-gel method. The prepared samples were characterized by XRD, FESEM, EDX, TEM, BET, BJH, VSM, XPS, FT-IR, and DRS-UV/Vis analysis. The photocatalytic effect of synthesized samples on naproxen degradation was studied. The operational parameters were optimized through central composite design to achieve maximum efficiency. The optimum values for maximum efficiency were obtained at pH of 4.29, catalyst mass of 0.06 g, naproxen concentration of 9.33 mg L, and irradiation time of 217.06 min. At these optimum conditions, the maximum photocatalytic degradation percentages of naproxen were found to be 96.32% at desirability function value of 1.0. Coupling the electrical current with the photocatalytic process proved that the electrical current was considerably efficient in decreasing the degradation time of removing the naproxen from aqueous solutions. The photocatalytic activity of the nanoparticles was also studied under sunlight. Considering the results provided by UV-Vis spectrophotometry and total organic carbon, it was found that the prepared samples are extraordinarily efficient to degrade naproxen under both purple LED and solar lights. Furthermore, the effect of different scavenger agents on naproxen degradation has been studied.
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http://dx.doi.org/10.1080/10934529.2019.1673609DOI Listing
December 2019

Salt-assisted liquid-liquid extraction in microchannel.

J Sep Sci 2019 Aug 6. Epub 2019 Aug 6.

Department of Chemistry, Science and Research Branch, Islamic Azad University, Tehran, Iran.

In this study, for the first time, salt-assisted liquid-liquid extraction was performed in a microchannel system. The proposed design is based on the increase of contact surface area between target analytes and extracting phase during the sample and extracting phase transfer in microchannel. In this method, first sample solution, extracting solvent, and salt were mixed by stirrer and simultaneously delivered into a microchannel using a syringe pump. In order to optimize the influential parameters on the extraction efficiency of the proposed method, zidovudine and tenofovir disoproxil fumarate were selected as model analytes. The main parameters such as extracting solvent and its volume, salt amount, pH of sample solution, and microchannel shape, length, and its inner diameter were investigated and optimized. Under the optimized conditions, the proposed method was linear in the range of 0.1-30 µg/mL and R coefficients were equal to 0.9922 and 0.9947 for zidovudine and tenofovir disoproxil fumarate, respectively. Extraction efficiency of the proposed method was compared with conventional salt-assisted liquid-liquid extraction. The results show that the proposed design has higher extraction efficiency than conventional salt-assisted liquid-liquid extraction. Finally, the proposed method was successfully applied for the determination of zidovudine and tenofovir disoproxil fumarate in plasma samples.
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http://dx.doi.org/10.1002/jssc.201900512DOI Listing
August 2019

Ultrasensitive separation of methylprednisolone acetate using a photoresponsive molecularly imprinted polymer incorporated polyester dendrimer based on magnetic nanoparticles.

J Sep Sci 2019 Apr 18;42(7):1468-1476. Epub 2019 Feb 18.

Tehran Chemie Pharmaceutical Co, Tehran, Iran.

We developed an approach for the use of polyester dendrimer during the imprinting process to raise the number of recognized sites in the polymer matrix and improve its identification ability. Photoresponsive molecularly imprinted polymers were synthesized on modified magnetic nanoparticles involving polyester dendrimer which uses the reactivity between allyl glycidyl ether and acrylic acid for the high-yielding assembly by surface polymerization. The photoresponsive molecularly imprinted polymers were constructed using methylprednisoloneacetate as the template, water-soluble azobenzene involving 5-[(4, 3-(methacryloyloxy) phenyl) diazenyl] dihydroxy aniline as the novel functional monomer, and ethylene glycol dimethacrylate as the cross-linker. Through the evaluation of a series of features of spectroscopic and nano-structural, this sorbent showed excellent selective adsorption, recognition for the template, and provided a highly selective and sensitive strategy for determining the methylprednisoloneacetate in real and pharmaceutical samples. In addition, this sorbent according to good photo-responsive features and specific affinity to methylprednisoloneacetate with high recognition ability, represented higher binding capacity, a more extensive specific area, and faster mass transfer rate than its corresponding surface molecularly imprinted polymer.
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http://dx.doi.org/10.1002/jssc.201801093DOI Listing
April 2019

Synthesis of graphene by in situ catalytic chemical vapor deposition of reed as a carbon source for VOC adsorption.

Environ Sci Pollut Res Int 2019 Feb 8;26(4):3643-3650. Epub 2018 Dec 8.

Department of Basic Sciences, Islamic Azad University, Science and Research Branch, Tehran, 14778-93855, Iran.

Few-layer graphene was synthesized by in situ catalytic carbon vapor deposition (CCVD) method, using reed as a carbon source and Ni, Cu, and Mg salts as the catalyst compounds. The synthesized graphene was also used for adsorption of VOCs. Furthermore, the effect of organic additives, sorbitol, and citric acid on catalyst compounds was investigated by temperature-programmed reduction analysis (H-TPR). The products' properties were characterized by thermo-gravimetric analysis (TGA), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), and Brunauer-Emmett-Teller (BET) surface area analysis. TEM and FE-SEM images confirmed the formation of graphene sheets. Activation of the graphene by phosphoric acid at 500 °C and then by CO at 800 °C increased the surface area from 298 to 568 m/g. Gasoline working capacity of the activated graphene was 65.24 g/l. Graphical abstract Few-layer graphene was synthesized by in situ catalytic carbon vapor deposition (CCVD) method using reed as a carbon source and Ni, Cu, and Mg salts as the catalyst compounds and used for adsorption of VOCs.
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http://dx.doi.org/10.1007/s11356-018-3799-8DOI Listing
February 2019

Erratum to "Comparison between Different Extraction Methods for Determination of Primary Aromatic Amines in Food Simulant".

J Anal Methods Chem 2018 6;2018:6423428. Epub 2018 Sep 6.

Department of Analytical Chemistry, Faculty of Basic Science, Science and Research Branch, Islamic Azad University, Tehran, Iran.

[This corrects the article DOI: 10.1155/2018/1651629.].
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http://dx.doi.org/10.1155/2018/6423428DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6146773PMC
September 2018

Providing hyper-branched dendrimer conjugated with β-cyclodextrin based on magnetic nanoparticles for the separation of methylprednisolone acetate.

J Chromatogr A 2018 Oct 2;1571:38-46. Epub 2018 Aug 2.

Tehran Chemie Pharmaceutical Co., Tehran, Iran.

This study introduced a developed approach for dendritic β-cyclodextrin (β-CD) in order to obtain high sorption capacity. Synthetic strategy exploits the reactivity between acrylic acid and allyl glycidyl ether for high-yielding assembly via grafting on to the magnetic nanoparticles that are modified using 3-mercaptopropyltrimethoxysilane for various building branches and host-guest molecules of β-CD. The methodology has been applied for the preparation of a series of β-CD conjugated magnetic nanoparticles with dendrimers as a nano-sorbent for the extraction of methylprednisolone acetate. This study allowed us to probe (i) the effects of the dendric-cyclodextrin architecture on the affinity of sorption capacity, (ii) the drug influence between the cyclodextrin core and the polyester dendrimer, and (iii) the result of sorbent formation for using the anti-inflammatory drug as a target guest into the ring of β-CD on biological extraction. It was found that the adsorption behavior could be fitted by the Langmuir adsorption isotherm model. The adsorption capacity of MPA is found to be 12.4 mg g and indicated the homogeneous sites onto polymer grafted magnetite nano-sorbent surface. Our results confirm the high capability of this type of dendrimer-β-CD for drug extraction in biological fluids and pharmaceutical samples. This nano-sorbent assists the magnetic solid phase extraction technique represented in the high extraction yield (up to 97%) for methylprednisolone acetate in biological human fluids and pharmaceutical samples. Moreover, the achieved polymeric nano-sorbent of the reaction combination was facilitated by a magnetic field and reusability was performed without any notable loss in the sorbent activity.
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http://dx.doi.org/10.1016/j.chroma.2018.08.005DOI Listing
October 2018

Essential oil composition and in vitro antibacterial activity of Chenopodium album subsp. striatum.

Acta Biol Hung 2018 Jun;69(2):144-155

7 Phytochemistry Research Center, Shahid Beheshti University of Medicinal Sciences , Tehran , Iran.

The objective of this study was to identify the bioactive compounds of essential oil and evaluate the antibacterial activity of the essential oil extracted from Chenopodium album subsp. striatum against multidrug-resistant bacterial strains (MDR) which were isolated from clinical specimens by conventional methods. Furthermore, eight different Gram-negative and Gram-positive multidrug-resistant bacterial strains were used to investigate the antibacterial potential of the essential oil. The antibacterial activity was tested using MIC and MBC microdilution method, well and disc diffusion in different concentration. The hydro-distillation of aerial parts powder yield was 0.466% (v/w). Essential oil showed bactericidal activity against both MDR Gram-negative and Gram-positive bacterial strains. MIC and MBC results were ranged from 0.31 to 2.5 and 0.62 to 5.0 mg/mL. The inhibition zones in well-diffusion method were ranged from 7 ± 0.6 mm to 15 ± 1.0 mm. Disc diffusion method was ranged from 7 ± 0.0 mm to 16 ± 0.6 mm depending on the type of bacteria strain and essential oil concentration. Essential oil of Ch. album had the greatest potential to be considered as an antibacterial agent against MDR bacteria strain. This potential was due to different biological and bioactive compounds like phytol, linalool, α-terpineol and linolenic acid in the plant.
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http://dx.doi.org/10.1556/018.69.2018.2.4DOI Listing
June 2018

Comparison between Different Extraction Methods for Determination of Primary Aromatic Amines in Food Simulant.

J Anal Methods Chem 2018 15;2018:1651629. Epub 2018 May 15.

Department of Analytical Chemistry, Faculty of Basic Science, Science and Research Branch, Islamic Azad University, Tehran, Iran.

The primary aromatic amines (PAAs) are food contaminants which may exist in packaged food. Polyurethane (PU) adhesives which are used in flexible packaging are the main source of PAAs. It is the unreacted diisocyanates which in fact migrate to foodstuff and then hydrolyze to PAAs. These PAAs include toluenediamines (TDAs) and methylenedianilines (MDAs), and the selected PAAs were 2,4-TDA, 2,6-TDA, 4,4'-MDA, 2,4'-MDA, and 2,2'-MDA. PAAs have genotoxic, carcinogenic, and allergenic effects. In this study, extraction methods were applied on a 3% acetic acid as food simulant which was spiked with the PAAs under study. Extraction methods were liquid-liquid extraction (LLE), dispersive liquid-liquid microextraction (DLLME), and solid-phase extraction (SPE) with C18 ec (octadecyl), HR-P (styrene/divinylbenzene), and SCX (strong cationic exchange) cartridges. Extracted samples were detected and analyzed by HPLC-UV. In comparison between methods, recovery rate of SCX cartridge showed the best adsorption, up to 91% for polar PAAs (TDAs and MDAs). The interested PAAs are polar and relatively soluble in water, so a cartridge with cationic exchange properties has the best absorption and consequently the best recoveries.
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http://dx.doi.org/10.1155/2018/1651629DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5977034PMC
May 2018

A novel impedimetric glucose biosensor based on immobilized glucose oxidase on a CuO-Chitosan nanobiocomposite modified FTO electrode.

Int J Biol Macromol 2018 Oct 31;118(Pt A):649-660. Epub 2018 May 31.

Department of Chemistry, Science and Research Branch, Islamic Azad University, Tehran, Iran.

This research aims at elaborating on the construction of a novel nanostructured copper oxide (Nano-CuO) sputtered thin film on the conductive fluorinated-tin oxide (FTO) layer that was exploited to immobilize glucose oxidase (GOx) enzyme via chitosan for developing impedimetric glucose biosensing. The distinct Nano-CuO thin film was fabricated by reactive DC magnetron sputtering system at the optimized instrumental deposition conditions. The FTO/Nano-CuO/Chitosan/GOx biosensor containing several layers afforded excellent microenvironment for rapid biocatalytic reaction to glucose. Field emission-scanning electron microscopy (FE-SEM), Ultraviolet-Visible spectroscopy (UV-Vis), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) were established the morphology of modified electrode's surface and electrochemical behavior of glucose on the fabricated biosensor. Characterization of the surface morphology and roughness of CuO thin film by FE-SEM exhibits cavities of the nanoporous film as an effective biosensing area for covalent enzyme immobilization. Invented FTO/Nano-CuO/Chitosan/GOx biosensor was employed for glucose determination using the impedimetric technique. The impedimetric outcomes display high sensitivity for glucose (0.261 kΩ per mM) detection within 0.2-15 mM and limit of detection as 27 μM. The declared biosensor has been applied as a careful, noncomplicated, and exact biosensor for recognition of glucose in the real samples analysis.
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http://dx.doi.org/10.1016/j.ijbiomac.2018.05.228DOI Listing
October 2018

Facile preparation of multifunctional carbon nanotube/magnetite/polyaniline nanocomposite offering a strong option for efficient solid-phase microextraction coupled with GC-MS for the analysis of phenolic compounds.

J Sep Sci 2018 Jul 29;41(13):2736-2742. Epub 2018 May 29.

Department of Chemistry, Science and Research Branch, Islamic Azad University, Tehran, Iran.

The aim of this study was to synthesize a highly efficient organic-inorganic nanocomposite. In this research, the carbon nanotube/magnetite/polyaniline nanocomposite was successfully prepared through a facile route. Monodisperse magnetite nanospheres were prepared through the coprecipitation route, and polyaniline nanolayer as a modified shell with a high surface area was synthesized by an in situ growth route and characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray diffraction, and energy-dispersive X-ray spectroscopy. The prepared nanocomposite was immobilized on a stainless-steel wire for the fabrication of the solid-phase microextraction fiber. The combination of headspace solid-phase microextraction using carbon nanotube/magnetite/polyaniline nanocomposite fiber with gas chromatography and mass spectrometry can achieve a low limit of detection and can be applied to determine phenolic compounds in water samples. The effects of the extraction and desorption parameters including extraction temperature and time, ionic strength, stirring rate, pH, and desorption temperature and time have been studied. Under the optimum conditions, the dynamic linear range was 0.01-500 ng/mL and the limits of detection of phenol, 4-chlorophenol, 2,6-dichlorophenol, and 2,4,6-trichlorophenol were the lowest (0.008 ng/mL) for three times. The coefficient of determination of all calibration curves was more than 0.990.
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http://dx.doi.org/10.1002/jssc.201800062DOI Listing
July 2018

Fe(3)O(4)/polyethylene glycol nanocomposite as a solid-phase microextraction fiber coating for the determination of some volatile organic compounds in water.

J Sep Sci 2017 02 30;40(3):717-724. Epub 2017 Jan 30.

Department of Chemistry, Science and Research Branch, Islamic Azad University, Tehran, Iran.

A high-performance metal oxide polymer magnetite/polyethylene glycol nanocomposite was prepared and coated in situ on the surface of the optical fiber by sol-gel technology. The magnetite nanoparticles as nanofillers were synthesized by a coprecipitation method and bonded with polyethylene glycol as a polymer. The chemically bonded coating was evaluated for the headspace solid-phase microextraction of some environmentally important volatile organic compounds from aqueous samples in combination with gas chromatography and mass spectrometry. The prepared fiber was characterized by scanning electron microscopy and Fourier transform infrared spectroscopy. The mass ratio of nanofiller and polymer on the coating extraction efficiency, morphology, and stability were investigated. The parameters affecting the extraction efficiency, including the extraction time and temperature, the ionic strength, desorption temperature, and time were optimized. The sol-gelized fiber showed excellent chemical stability and longer lifespan. It also exhibited high extraction efficiency compared to the two types of commercial fibers. For volatile organic compounds analysis, the new fiber showed low detection limits (0.008-0.063 ng/L) and wide linearity (0.001-450 × 10 ng/L) under the optimized conditions. The repeatability (interday and intraday) and reproducibility were 4.13-10.08 and 5.98-11.61%, and 7.35-14.79%, respectively (n = 5). For real sample analysis, three types of water samples (ground, surface, and tap water) were studied.
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http://dx.doi.org/10.1002/jssc.201600888DOI Listing
February 2017

Solid-phase nanoextraction of polychlorinated biphenyls in water and their determination by gas chromatography with electron capture detector.

J Sep Sci 2017 01 13;40(2):449-457. Epub 2016 Dec 13.

Veterinary Organization, Tehran, Iran.

A solid-phase nanoextraction method has been developed for the extraction and preconcentration of polychlorinated biphenyls using carboxyl multiwalled carbon nanotubes as a solid nano-sorbent. Parameters affecting extraction efficiency such as sorbent amount, desorption solvent type and volume, extraction time, pH, and salt content have been studied. Under optimized conditions, the correlation coefficient was up to 0.9989, the limits of detection was in the range of 1.4-3.5 ng/L, and limits of quantification was between 4.8 and 11.6 ng/L. The recoveries were in the range of 99-106% for different spiked analytes. The relative standard deviation for water samples spiked with two different spiking levels has been between 4 and 10%. The proposed sustainable method is rapid, easy to use, and small consumption of organic solvent for the detection and determination of trace levels of polychlorinated biphenyls in environmental waters.
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http://dx.doi.org/10.1002/jssc.201600720DOI Listing
January 2017

Potent Antioxidant Properties of rolB-transformed Catharanthus roseus (L.) G. Don.

Iran J Pharm Res 2016 ;15(2):537-50

Department of Chemistry, Science and Research Branch, Islamic Azad University, Tehran, Iran.

Free radicals play an important role in pathological processes such as aging and developing cancer; hence, natural products inhibit free radical production, and can play an important role in preventing diseases. We aimed to evaluate the scavenging activity of free radicals, reducing power, inhibition of lipid peroxidation and malondialdehyde (MDA) formation, and the antioxidant composition of rolB-transformed hairy roots and leaf callus of Catharanthus roseus. Hairy roots of the Catharanthus roseus were induced using Agrobacterium rhizogenes strain ATCC 15834 to transfer the rolB gene. Polymerase chain reaction analysis was used to identify the presence of the gene in the transformed hairy roots. Folin-Ciocalteu reagent, aluminum chloride calorimetry and high performance liquid chromatography were used to determine the content of total phenolic, flavonoid and gallic acid, respectively. To this end, we assayed the free radicals scavenging activity by 1-diphenyl-2-picrylhydrazyl (DPPH), reducing power, inhibition of lipid peroxidation and inhibition of malondialdehyde production. The results showed that phenolic, flavonoid, and gallic acid contents in the ethanol extract of the hairy roots were significantly higher (p ≤ 0.01) than those naturally found in the extracts of root, leaf, and leaf callus of C. roseus. The hairy roots extract showed the lowest IC50 for the inhibition of DPPH(•). Furthermore, the ethanol extract showed the best reducing power and had the highest potential to inhibit lipid peroxidation and to form the MDA. The transformed hairy roots can be considered a rich natural source of antioxidants.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5018282PMC
September 2016

A fabricated electro-spun sensor based on Lake Red C pigments doped into PAN (polyacrylonitrile) nano-fibers for electrochemical detection of Aflatoxin B1 in poultry feed and serum samples.

Analyst 2015 Nov;140(22):7761-7

Department of Mechanical Engineering, Engineering Faculty, Razi University, Kermanshah, Iran.

The aim of this work was to fabricate a novel nano-fiber modified electrode, involving Lake Red C (LRC) pigments doped into electrospun polyacrylonitrile (PAN) fibrous films. Cyclic voltammetry (CV), scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV) techniques were used for electrochemical and morphological characterization of the composite fibers. This sensor responds to Aflatoxin B1 (AFB1) over the concentration range of 40-120 nM with high accuracy and precision in analysis. The modified electrode exhibited an excellent electrocatalytic ability (α = 0.42, log K(s) = 4.21 s(-1), and Γ = 1.49 × 10(-5) mmol cm(-2)) for reduction of AFB1 at the optimum pH of 6 and working potential of -0.75 V (vs. SCE). The common substances accompanying AFB1 had no serious interferences on the response of the modified electrode to AFB1. The modified electrode indicated reproducible behavior and a high level stability during the experiments, making it particularly suitable for the analytical determination of AFB1 in poultry feed and serum samples.
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http://dx.doi.org/10.1039/c5an01602aDOI Listing
November 2015

Determination of residual nonsteroidal anti-inflammatory drugs in aqueous sample using magnetic nanoparticles modified with cetyltrimethylammonium bromide by high performance liquid chromatography.

ScientificWorldJournal 2014 1;2014:127835. Epub 2014 Jun 1.

Department of Chemistry, Science and Research Branch, Islamic Azad University, Poonak Hesarak, Tehran, Iran.

A simple and sensitive solid-phase extraction method for separation and preconcentration of trace amount of four nonsteroidal anti-inflammatory drugs (naproxen, indomethacin, diclofenac, and ibuprofen) using Fe3O4 magnetic nanoparticles modified with cetyltrimethylammonium bromide has been developed. For this purpose, the surface of MNPs was modified with cetyltrimethylammonium bromide (CTAB) as a cationic surfactant. Effects of different parameters influencing the extraction efficiency of drugs including the pH, amount of salt, shaking time, eluent type, the volume of solvent, amount of adsorbent, sample volume, and the time of desorption were investigated and optimized. Methanol has been used as desorption solvent and the extracts were analysed on a reversed-phase octadecyl silica column using 0.02 M phosphate-buffer (pH = 6.02) acetonitrile (65 : 35 v/v) as the mobile phase and the effluents were measured at 202 nm with ultraviolet detector. The relative standard deviation (RSD%) of the method was investigated at three concentrations (25, 50, and 200 ng/mL) and was in the range of 3.98-9.83% (n = 6) for 50 ng/mL. The calibration curves obtained for studied drugs show reasonable linearity (R (2) > 0.99) and the limit of detection (LODs) ranged between 2 and 7 ng/mL. Finally, the proposed method has been effectively employed in extraction and determination of the drugs in biological and environmental samples.
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http://dx.doi.org/10.1155/2014/127835DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4058801PMC
April 2015

Polyvinylimidazole/sol-gel composite as a novel solid-phase microextraction coating for the determination of halogenated benzenes from aqueous solutions.

J Sep Sci 2014 Jun 15;37(12):1475-81. Epub 2014 May 15.

Department of Chemistry, Science and Research Branch, Islamic Azad University, Tehran, Iran.

A polyvinylimidazole/sol-gel composite is proposed as a novel solid-phase microextraction fiber to extract five halobenzenes from the headspace of aqueous solutions in combination with gas chromatography with mass spectrometry. The prepared fiber was characterized by scanning electron microscopy and Fourier transform infrared spectroscopy. The obtained results showed that porous polyvinylimidazole/sol-gel composite was chemically deposited on fused silica fiber. The effect of important extraction parameters including extraction temperature, extraction time, and salt content were investigated. The optimum conditions were as follows: extraction temperature 25°C, extraction time 20 min, and salt concentration 30 w/v%. Detection limits and relative standard deviations of the developed method for halogenated benzenes were below 0.1 pg/mL and 15%, respectively. Repeatability of the proposed method, explained by relative standard deviation, varied between 5.48 and 9.15% (n = 5). The limits of detection (S/N = 3) ranged between 0.01 and 0.10 ng/L using gas chromatography with mass spectrometry with selected ion monitoring mode. For real sample analysis, three types of water samples with different matrices (ground, surface, and tap water) were studied. The optimized procedure was applied to extraction and method validation of halogenated benzenes in spiked water samples.
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http://dx.doi.org/10.1002/jssc.201301238DOI Listing
June 2014

A single step technique for preparation of porous solid phase microextraction fibers by electrochemically co-deposited silica based sol-gel/Cu nanocomposite.

J Chromatogr A 2013 Feb 21;1278:1-7. Epub 2012 Nov 21.

Department of Chemistry, Science and Research Branch, Islamic Azad University, P.O. Box 14515-775, Tehran, Iran.

In this study, electrochemically co-deposited 3-trimethoxysilyl propyl methacrylate (3TMSPMA)/Cu nanocomposite is introduced as a novel and single-step technique for preparation of efficient and unbreakable solid phase microextraction (SPME) fibers; having strong interaction between the substrate and the coating. The applicability of prepared nanocomposite films was evaluated through extraction of some aromatic pollutants as model compounds from the headspace of aqueous samples in combination with gas chromatography-mass spectrometry (GC-MS). Different parameters affecting the structure and composition of the deposited films including applied potential, electrodeposition time, and precursor concentration; and the parameters affecting extraction efficiency such as extraction temperature, extraction time, and salt content were investigated. The results showed that morphology and grain size of the films are strongly affected by the ratio between the sol-gel precursor and Cu(2+) ions. Furthermore, potential of deposition influences the composition of films as it controls the kinetics of sol-gel/Cu co-deposition. Finally, characterization of the deposited films was accomplished by scanning electron microscopy (SEM) and thermogravimetric analysis (TGA).
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http://dx.doi.org/10.1016/j.chroma.2012.11.035DOI Listing
February 2013

A novel strategy to increase performance of solid-phase microextraction fibers: electrodeposition of sol-gel films on highly porous substrate.

J Sep Sci 2012 Dec 29;35(23):3354-60. Epub 2012 Oct 29.

Department of Chemistry, Science and Research Branch, Islamic Azad University, Tehran, Iran.

In the present work, the effect of substrate porosity for preparation of solid-phase microextraction (SPME) fibers was investigated. The fibers were prepared by electrodeposition of sol-gel coatings using negative potentials on porous Cu wire and compared with previous reported technique for preparation of SPME fibers using positive potentials on smooth gold wire. Porous substrate was prepared by electrodeposition of a thin layer of Cu on a Cu wire. The extraction capability of prepared fibers was evaluated through extraction of some aromatic hydrocarbons from the headspace of aqueous samples. The effect of substrate porosity and some operating parameters on extraction efficiency was optimized. The results showed that extraction efficiency of SPME fibers highly depends on porosity of the substrate. The LOD ranged from 0.005 to 0.010 ng/mL and repeatability at the 1 ng/mL was below 12%. Electrodeposited films were characterized for their surface morphology and thermal stability using SEM and thermogravimetric analysis, respectively. SEM analysis revealed formation of porous substrate and subsequently porous coating on the wire surface and thermogravimetric analysis showed high thermal stability of the prepared fiber.
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http://dx.doi.org/10.1002/jssc.201200580DOI Listing
December 2012

5,5'-Dimeth-oxy-2,2'-[4,5-dimethyl-o-phenyl-enebis(nitrilo-methyl-idyne)]diphenol.

Acta Crystallogr Sect E Struct Rep Online 2010 Mar 3;66(Pt 4):o728. Epub 2010 Mar 3.

In the crystal structure of the title compound, C(24)H(24)N(2)O(4), the dihedral angles between the central and the two outer benzene rings are 48.12 (8) and 21.44 (8)°. Intra-molecular O-H⋯N hydrogen bonding generates S(6) rings.
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http://dx.doi.org/10.1107/S1600536810007282DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2983852PMC
March 2010

Antibacterial diterpenoids from Astragalus brachystachys.

Z Naturforsch C J Biosci 2002 Nov-Dec;57(11-12):1016-21

Laboratory of Ecological Chemistry, Division of Applied Bioscience, Graduate School of Agriculture, Hokkaido University, Kita-ku, Sapporo 060-8589, Japan.

Antibacterial bioassay guided fractionation of acetone extracts of Astragalus brachystachys resulted in isolation of sclareol and two related labdane-type diterpenoids, 14R-epoxysclareol and 6beta-hydroxysclareol. The antibacterial activity of the isolated compounds was measured and it was deduced that the epoxidation at the double bond of sclareol or hydroxylation at C-6 decreased the activity of the resulting compounds. Salvigenin (5-hydroxy-4',6,7-trimethoxyflavone) was also separated from this plant for the first time.
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http://dx.doi.org/10.1515/znc-2002-11-1211DOI Listing
April 2003
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