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    Polypropylene-based microextraction method for determination of fluoxetine in human urine samples

    , Article Analytical Letters ; Volume 45, Issue 13 , 2012 , Pages 1777-1785 ; 00032719 (ISSN) Bagheri, H ; Marzancola, M. G ; Es'haghi, A ; Sharif University of Technology
    A polypropylene (PP) sheet was successfully applied as an extracting medium for trace enrichment of fluoxetine (FLX) from urine samples, followed by high performance liquid chromatography-fluorescence detection (HPLC-FD). The extraction medium was a square, 1 × 1 cm2 piece of polypropylene membrane sheet that was conditioned in methanol. The extraction process was conveniently carried out using a 5 mL urine sample. After extraction, the PP sheet was withdrawn and transferred to a glass vial for performing the desorption process using 210 μL organic solvent. After complete drying, the residue was dissolved in 50 μL of methanol and an aliquot of 20 μL was, finally, injected into the HPLC... 

    On-line trace enrichment of phenolic compounds from water using a pyrrole-based polymer as the solid-phase extraction sorbent coupled with high-performance liquid chromatography

    , Article Analytica Chimica Acta ; Volume 513, Issue 2 , 2004 , Pages 445-449 ; 00032670 (ISSN) Bagheri, H ; Mohammadi, A ; Salemi, A ; Sharif University of Technology
    A pyrrole-based conductive polymer was prepared and applied as new sorbent for on-line solid-phase extraction (SPE) of phenol and chlorophenols from water samples. Polypyrrole (PPy) was synthesized by chemical oxidation of the monomer in non-aqueous solution. The efficiency of this polymer for extraction of phenol and chlorophenols was evaluated using 35 mg of PPy as the sorbent in an on-line SPE system coupled to reversed-phase liquid chromatography with UV detection. The mobile phase were mixture of phosphate buffer-acetonitrile and compounds were eluted by the mobile phase using a six-port switching valve. High volumes of water, up to 160 ml, could be preconcentrated without the loss of... 

    Evaluation of polyaniline as a sorbent for SPE of a variety of polar pesticides from water followed by CD-MEKC-DAD

    , Article Chromatographia ; Volume 59, Issue 5-6 , 2004 , Pages 283-289 ; 00095893 (ISSN) Bagheri, H ; Saraji, M ; Barceló, D ; Sharif University of Technology
    A recently synthesized polyaniline (PANI) has been used and evaluated as a sorbent for solid-phase extraction of a variety of polar pesticides and some of their degradation products from water samples. Several classes of pesticides including phenoxy acids, triazines, ureas, oxime carbamates and carbamates were selected for this study. The determination of these pesticides was carried out using cycladextrin modified micellar electrokinetic chromatography equipped with diode array detection. The recovery results using PANI were compared with those obtained by C18, Isolute ENV+, Oasis HLB and LiChrolut EN. Effect of humic acid, as a major interference, on extraction recovery was also studied.... 

    Coupling of a modified in-tube solid phase microextraction technique with high performance liquid chromatography-fluorescence detection for the ultra-trace determination of polycyclic aromatic hydrocarbons in water samples

    , Article Chromatographia ; Volume 59, Issue 7-8 , 2004 , Pages 501-505 ; 00095893 (ISSN) Bagheri, H ; Salemi, A ; Sharif University of Technology
    Friedr. Vieweg und Sohn Verlags GmbH  2004
    A modified in-tube solid phase microextraction (SPME) technique in conjunction with a high performance liquid chromatography (HPLC) was developed for the trace determination of polycyclic aromatic hydrocarbons (PAHs) in water samples. The extraction device contained a regular HPLC syringe, replacing the metallic needle by two concentric fused silica capillary tubes. The capillary tubes were coated with polydimethylsiloxane (PDMS) as the sorbent and were attached to the syringe by a homemade interface made from polyether ether ketone (PEEK). The sorption of analytes was achieved by frequent withdrawing and ejecting the water sample from/into a vial via the capillary tubes. For the desorption... 

    Determination of the pesticide naptalam and its degradation products by positive and negative ion mass spectrometry

    , Article Fresenius' Journal of Analytical Chemistry ; Volume 369, Issue 2 , 2001 , Pages 176-183 ; 09370633 (ISSN) Ghassempour, A ; Arshadi, M. R ; Asghari, F. S ; Sharif University of Technology
    N-1-naphthylphtalamic acid (naptalam) and its degradation products, 1-naphthylamine and N-(1-naphthyl) phthalimide were simultaneously determined in river water by two independent mass spectrometric (MS) methods. These were negative ion MS (NIMS) and programmable temperature vaporizer gas chromatography mass spectrometry (PTV-GC MS) with electron impact ionization (positive ions). Prior to the NIMS analysis, the samples were preconcentrated by solid phase extraction (SPE) of C18 membrane discs. The PTV-GC MS studies were performed without any preconcentration procedure. Selected ion monitoring (SIM) and internal standardization with naphthalene were applied in both methods. The limits of... 

    Characterization of Essential Oil Components of Green and Black Cardamoms Using GC-MS Combined with Chemometric Resolution Techniques & Quantification of Two Types of Taxus Using Fast Liquid Chromatography Combined with MCR

    , M.Sc. Thesis Sharif University of Technology karimi, Mehdi (Author) ; Jalali Heravi, Mehdi (Supervisor)
    Progress in analysis of multicomponent mixtures and processes focused on the interpretation of the multivariate responses, rely on the combination of sophisticated instrumental techniques and suitable chemometric methods. Among the present chemometric method, curve resolution techniques have a wide application in the analysis of multicomponent mixtures and processes. Chemometric resolution techniques are used in the present work. At the first, Essential oil of green and black cardamoms was extracted by hydrodistillation and was analyzed by gas chromatography–mass spectrometry (GC-MS). Due to the fact that the essential oils are complex mixtures, strong overlap is observed between the peaks.... 

    Application of Diazonium Salts for Grafting the Sol-gel Based Sorbents: A New Approach Towards Unbreakable SPME

    , M.Sc. Thesis Sharif University of Technology Bayat, Parisa (Author) ; Bagheri, Habib (Supervisor)
    A novel application of diazonium salts for grafting the sol-gel based sorbents was sucessfully introduced. Preparation of unbrekable sorbents has been on highly demand and sough after by many researches for several years. However, there are a few achivements in this regard, but it still remains as a big challenge.Regarding to this issue, diazonium salts were sucessfully applied for functionalizing the different substrates, in which there is no limitation in selection of substrates. Different substrates, metallic and non metallic, such as copper, brass, stailess steel and PTFE were chosen to be functionalized by chemical or electrochemical reduction of 4-Amino phenyl acetic acid. Then,... 

    A Polypropylene-Based Microextraction Method Coupled with HPLC-FD for Determination of Fluoxetine in Human

    , M.Sc. Thesis Sharif University of Technology Gharibi Marzankola, Mahsa (Author) ; Bagheri, Habib (Supervisor)
    Considering principles of both micro-solid phase extraction (µ-SPE) and stir-bar sorptive extraction (SBSE) techniques, in this study a microextraction technique was developed using a polypropylene sheet as extracting device for isolation of fluoxetine from biological samples. Being rather inexpensive and simple to prepare extracting device, elimination of time consuming sorbent synthesis step and memory effect are some of the advantages of the proposed method. The extraction process was performed using a polypropylene sheet as extracting device. Solvent desorption was performed in a microvial and then extractant was injected into HPLC system. The effect of various parameters including pH,... 

    Analysis of bioactive constituents of saffron using ultrasonic assisted emulsification microextraction combined with high-performance liquid chromatography with diode array detector: A chemometric study

    , Article RSC Advances ; Volume 5, Issue 33 , 2015 , Pages 26246-26254 ; 20462069 (ISSN) Chaharlangi, M ; Parastar, H ; Malekpour, A ; Sharif University of Technology
    Royal Society of Chemistry  2015
    In recent years, there has been an increasing interest in the analysis of the major active components of saffron owing to their significant role in various industries, such as food, medicine and perfume. In other words, analysis of the major active components of saffron can give complete information about its chemical composition, which can be used as a reliable index for the quality control of different saffron samples (i.e., natural and commercial). The aim of the present work was to develop a simple, low cost, efficient and comprehensive strategy for the extraction and analysis of the bioactive components of saffron. In this regard, ultrasonic-assisted solvent extraction (UASE) combined... 

    High-Throughput Sample Preparation on a 96-Well Plate and LC-MS Analysis of Thimerosal in Biological Products

    , M.Sc. Thesis Sharif University of Technology Khakinejad, Mahdiar (Author) ; Bagheri, Habib (Supervisor) ; Eshaghi, Ali (Supervisor)
    Thiomersal is an organomercury compound. This compound is a well established antiseptic and antifungal agent. It has been used as a preservative in vaccines, immuno-globulin preparations, skin test antigens, antivenins, ophthalmic and nasal products, and tattoo inks. Thiomersal is very toxic by inhalation, ingestion, and in contact with skin, with a danger of cumulative effects. It is also very toxic to aquatic organisms and may cause long-term adverse effects in aquatic environments.
    Thiomersal's main use is as an antiseptic and antifungal agent in vaccines. In multidose injectable drug delivery systems, it prevents serious adverse effects such as the Staphylococcus infection that,... 

    Liquid-liquid-liquid microextraction and high performance liquid Chromatography for Seperation and Determination of Estrogens in Aquatic Media

    , M.Sc. Thesis Sharif University of Technology Maleki, Hossein (Author) ; Bagheri, Habib (Supervisor)
    Liquid-liquid-liquid microextraction (LLLME) is a new miniaturized liquid extraction to preconcentrate and purify for ionizable analytes. In LLLME firstly analytes extracted in an organic phase, and subsequently back-extracted into a second aqueous phase. Main advantages of LLME are their speed, simplicity, negligible volume of solvents, analytical precision, short sample preparation and low cost. This technique was shown to be an efficient preconcentration method for the extraction of estrone and estriol from biological samples. A basic microdrop in the tip of microsyringe was fixed in the organic layer over the sample solution. After extraction for a preset time, the microdrop was... 

    Synthesis and Optimization of Endohedral Metall of Ullerene Production in Arc Reactor Applying Vertical Graphite Electrodes

    , M.Sc. Thesis Sharif University of Technology Zarepour Jevinani, Morteza (Author) ; Ghanbari, Bahram (Supervisor)
    One of the considerable issues in fullereneresearch is low yield of endohedral fullerene production.In this project, synthesis and optimization of endohedral metallofullereneproduction was undertaken byarc reactor applying vertical graphite electrodes, using vaporizing composite lanthanum-oxide-graphite-dopped rod. Increasing the efficiency of endohedral fullerrene production in sootwas followed applyingcarbide formation in electrode which was studied by X-ray diffraction(XRD), thermogravimetric analysis(TGA) and infrared (IR) spectroscopy. In addition, as a simple and fast method, the liquid column chromatography was applied in separation and purification of fullerenes as well as endohedral... 

    On-line SPE of Clodinafop Propargyl Traces from Aquatic Media Using Electrospun Polyamide Nanofibers Disks

    , M.Sc. Thesis Sharif University of Technology Asgari, Sara (Author) ; Bagheri, Habib (Supervisor)
    An on-line solid phase extraction (SPE) method coupled with high performance liquid chromatography (HPLC) was developed using electrospun polyamide (PA) nanofibers as the extractin medium for trace determination of clodinafop propargyl herbicide in environmental aqueous samples. The sufficient numbers of disc sheets were cut from the electrospun PA mat and used as packing material in a cartridge. The homogeneity and the porosity of the prepared PA sheet were studied using the scanning electron microscopy (SEM) and the observed nanofiber diameters and lengths proved that the prepared sorbent possess a high aspect ratio. Major parameters affecting the extraction efficiency were optimized. The... 

    Electrospun Functionalized Silica / Polyvinyl Alcohol Nanofibers for On-Line μ-Solid Phase Extraction of Estrone and Estradiol in Biological Samples

    , M.Sc. Thesis Sharif University of Technology Taheri, Navid (Author) ; Bagheri, Habib (Supervisor)
    A method for determination of estrogens in biological samples was developed. This method was based on high performance liquid chromatography using online micro-solid phase extraction with 25 mg sorbent synthesized by electrospining of silica/PVA nanofibers. Poly (vinyl alcohol) (PVA) is an easily electrospun polymer with unique properties such as biocompatibility, processability, and hydrophilicity. Silica is biocompatible, thermally stable, and comparatively inert. Incorporation of silica with PVA produces hybrids with enhanced thermal and chemical stability in sample media and elution solvents without relinquishing the biocompatibility of PVA. The sufficient numbers of disc sheets were cut... 

    Novel Approach Towards Mechanical and Thermal Resistant Capillary Microextraction by Sol-Gel Technique in On-Line Combination with High Performance Liquid Chromatography

    , Ph.D. Dissertation Sharif University of Technology Piri-Moghadam, Hamed (Author) ; Bagheri, Habib (Supervisor)
    In this thesis, a new approach was developed to achieve mechanical and chemical resistant capillary microextraction (CME) in on-line combination with high performance liquid chromatography (HPLC) based on sol-gel technology. This thesis is divided into three chapters:
    First chapter contains of two parts. Overcoming the lack of mechanical stability of the substrate of CME by replacing the fused silica by copper tubings was the main objective of the first part. Self-assembled monolayers technique was employed to functionalize the copper tube followed by chemical bonding of the sorbent on the inner surface of the copper tube by sol-gel technology. The prepared copper tube containing the... 

    Synthesis and Implementation of Metal-organic Frameworks Based on Chromium Metal Salt in μ-solid Phase Extraction of Anti-hypertension Drugs in Biological Samples

    , M.Sc. Thesis Sharif University of Technology Sheshkhan, Abbas (Author) ; Bagheri, Habib (Supervisor)
    Several metal-organic frameworks based on chromium metal salt and terephthalic acid were synthesized by the solvo-thermal method and modified directly using amino acids or their imidazole derivatives. Suitable characteristics of the synthesized novel MOFs led to their use as novel extracting phases for sample preparation. The sorbent’s performance in extracting anti-hypertension drugs such as eprosartan, losartan and valsartan was tested using the magnetic solid phase extraction which is a form of μ-SPE, followed by HPLC analysis. Different parameters effecting the extraction and desorption procedures were optimized to achieve the highest performance of extraction and sensitivity. Said... 

    A horizontally oriented setup for liquid-liquid-liquid microextraction of estrogens

    , Article Analytical Methods ; Volume 5, Issue 22 , 2013 , Pages 6517-6522 ; 17599660 (ISSN) Bagheri, H ; Maleki, H ; Es'Haghi, A ; Sharif University of Technology
    A horizontally oriented liquid-liquid-liquid microextraction (HOLLLME) setup was developed and applied for the isolation of two major estrogens from aquatic media. In contrast to the conventional procedure, in this setup the extracting microdrop was suspended from a horizontally positioned needle in order to provide much higher stability to the extracting phase. The developed HOLLLME approach was applied to isolate two major selected estrogens from aquatic media followed by high performance liquid chromatography-ultraviolet (HPLC-UV) determination. Estrogens were, initially, extracted from water samples into hexane and subsequently, the back extraction stage was performed with 6 μL of sodium... 

    Supercritical extraction of phenanthrene in the crossover region

    , Article Journal of Chemical and Engineering Data ; Volume 50, Issue 1 , 2005 , Pages 49-51 ; 00219568 (ISSN) Esmaeilzadeh, F ; Goodarznia, I ; Sharif University of Technology
    An experimental flow-type apparatus has been tested for the separation of phenanthrene from a mixture of solids (phenanthrene, anthracene, and carbazole) and also from anthracene oil of the Isfahan Coal Tar Refining Company based on retrograde crystallization phenomena in supercritical carbon dioxide. The results show that by exploiting the crossover effect it is possible to obtain (82 and 24) mass % of phenanthrene from the solid mixture and anthracene oil, respectively, with a single temperature cycle  

    Modification of Evolving Factor Analysis and Multivariate Curve Resolution Methods and Using their Applications in Analysis of Medicinal Plants Essential Oils

    , Ph.D. Dissertation Sharif University of Technology Moazeni-Pourasil, Roudabeh (Author) ; Jalali-Heravi, Mehdi (Supervisor) ; Ghassempour, Alireza (Co-Advisor)
    Factor analysis based methods are one of the applied methods in the Chemometrics. In this regard, some modifications on one of the factor analysis based method named fixed size moving window evolving factor analysis were done and two new methods named variable size moving window evolving factor analysis and preselected variable size moving window evolving factor analysis were introduced. The performance of the new introduced methods were examined and compared by the fixed size moving window evolving factor analysis.
    Pure variable selection methods are useful for curve resolution methods which need to define an initial estimate from chromatographic profile or spectra. In this aspect the... 

    On-line micro solid-phase extraction of clodinafop propargyl from water, soil and wheat samples using electrospun polyamide nanofibers

    , Article Chromatographia ; Vol. 77, issue. 9-10 , May , 2014 , p. 723-728 Bagheri, H ; Asgari, S ; Piri-Moghadam, H ; Sharif University of Technology
    An on-line extraction/determination set up was designed for micro solid-phase extraction of clodinafop propargyl from water, soil and wheat samples using electrospun polyamide nanofiber mats. The prepared mats were packed in a stainless steel tube which conveniently acted as a high-performance liquid chromatography injection loop. Influential parameters affecting the extraction efficiency were optimized using a distilled water sample fortified with 25 μg L-1 of clodinafop propargyl. An enrichment factor of 440 was achieved for clodinafop propargyl indicating the ability of the whole procedure. Under the optimum conditions, the linearity for the analyte was in the range of 6-700 μg L-1, while...