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micro-solid-phase-extraction
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Electrospinning of Core-shell Nanofibers for Extraction and Determination of Pesticide Residues from Aquatic Media
, M.Sc. Thesis Sharif University of Technology ; Bagheri, Habib (Supervisor)
Abstract
Porosity and high surface area is a profound concept for creating advance materials. Nanofibers are an important class of nano materials which would be used as novel sorbents because of their high surface to volume ratio as a result of long lengths and nano-to-micro-scale diameters. Electrospining is a simple method for producing fine nanofibers from different meterials such as, polymers, composites and ceramics to prepare highly efficient sorbents. Moreover, electrospining has been developed for fabricating nanofibers with core-shell structures. These structures in compared with conventional fibers have gained higher attentions due to their high aspect ratios and flexiblity in surface...
Polybutylene Terephethalate-based Magnetic Nanofibers for Micro-solid phase Extraction of Triazines from Aquatic Media
, M.Sc. Thesis Sharif University of Technology ; Bagheri, Habib (Supervisor)
Abstract
Porosity and high surface area is a profound concept for creating advance materials. Nanofibers are an important class of nanomaterials with high surface to volume ratio as a result of long lengths and nano-to-micro-scale diameters. Electrospinning is a simple method for producing nanofibers from different polymers and composites and prepare highly efficient sorbents. Polymeric nanocomposites are claimed to exhibit markedly improved mechanical, magnetic, thermal and electrical properties. Magnetic iron oxide nanoparticles have gained great attentions due to their low toxicity, stability and biocompatibility and have been extensively used to induce magnetic property to the desired sorbents....
Modified Polystyrene Based Sorbents for Extraction of Trace Organic Pollutants with a Wide Range of Polarity
, Ph.D. Dissertation Sharif University of Technology ; Bagheri, Habib (Supervisor)
Abstract
The main focus of this thesis is based on surface modification of polystyrene in order to prepare extractive phases appropriate for extraction of analytes with a wide polarity range. This goal was achieved by increasing surface polarity. In fact, improved wettability and the possibility of interaction with polar analytes after addition of functional groups on polystyrene surface were the main reason for increased extraction capacity. In the first research, different functional groups including amine, nitro, carboxyl and acetyl were added on polystyrene particles by chemical bonding and to investigate their influence on extraction process, 22 analytes with a wide polarity range (LogP=-2 to...
Magnetic Field Assistedand Flow Injection μ-Solid Pahse Extraction Techniques
, M.Sc. Thesis Sharif University of Technology ; Bagheri, Habib (Supervisor)
Abstract
The main goal of this thesis was to develop μ-solid extraction techniques using electrspun nanofibers under the influence of magnetic field along with flow injection system. The thesis is divided into two sections:The first chapter deals with the use of magnetic field for improving μ-solid phase extraction efficiencies. After preparing the magnetic-based electrospun nanofibers (PBt/MNPs), sufficient numbers of disc from the prepared electrospun composite mat were cut and used as packing materials in a cartridge. The prepared system was coupled on-line to liquid chromatography for microextraction of selected drugs of furosemide, naproxene, diclofenac and clobetasol propionate. The homogeneity...
Modified Lignin Natural Polymer and Graphene Oxide Aerogels and Valuation of their Performance in Sample Preparation
, M.Sc. Thesis Sharif University of Technology ; Bagheri, Habib (Supervisor)
Abstract
A green aerogel was prepared by synthesizing amine-modified lignin from sugarcane bagasse and further modification by CS2 and subsequent freeze drying. This aerogel was implemented as an extractive phase in a home-made online micro solid phase extraction-high performance liquid chromatography (μSPE-HPLC) setup for analyzing cardiovascular drugs (valsartan and losartan) in urine samples. To study the effect of functionalization, bare or functionalized lignin powders were mixed with graphene oxide (GO) at different ratios while functionalized lignin showed the highest efficiency. The prepared aerogel was analyzed using CHNS elemental analysis, and FT-IR spectrometry. Effects of influencing...
Electrospun Nanofibers and Their Application for Microextraction of Environmental Samples
, Ph.D. Dissertation Sharif University of Technology ; Bagheri, Habib (Supervisor)
Abstract
Novel electrospun nanofibers and their applications as the microextractionsorbents are the centre of this research. Polymeric nanofibers with diameter in the scale of nano-to-micro were prepared by the electrospinning method and employed for microextraction purposes. Two major microextraction methods included solid phase microextraction (SPME) and micro-Solid phase extraction (µ-SPE). In the first work, a novel SPME fiber was fabricated by electrospinning method. A thin stainless steel wire was coated by the network of polymeric nanofibers. The polymeric nanofiber coating on the wire was mechanically stable due to the fine and continuous nanofibers formation around the wire with a three...
Synthesis and Application of Nanocomposites Containing Metallic Nanoparticles for Microextraction of Environmental and Biological Samples
, M.Sc. Thesis Sharif University of Technology ; Bagheri, Habib (Supervisor)
Abstract
This thesis deals with the synthesis and characterization of some nanostructured conductive polymers and their applications toward microextraction of drugs, environmental pollutants and pesticides from aqueous and biological samples. In chapters 3–6, silver nanoparticles and their relevant nanocomposites were applied as the desired extracting media while in the last chapter, a polyaniline nanocomposite, containing titanium oxide nanoparticles, was synthesized and employed as an efficient medium for the extraction purposes. In the first work, a nanocomposite based on polyaniline-silver nanoparticles (PANI-Ag NPs) was synthesized and used as an extraction medium for microextraction in packed...
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 ; Bagheri, Habib (Supervisor)
Abstract
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...
Polysaccharide-Based Nanocomposites as Green Sorbents in Microextraction Methodologies
, Ph.D. Dissertation Sharif University of Technology ; Bagheri, Habib (Supervisor)
Abstract
This thesis is focused on the preparation and use of polysaccharides as extractive phases in various extraction methods, such as the micro solid phase extraction (µ-SPE), needle trap microextraction (NTME) and thin film microextraction (TFME).In the first research, feasibility of the online µ-SPE method using cellulose acetate (CA) fibers was investigated. For this purpose, CA fibers were prepared by electrospinning technique and then placed into µ-SPE cartridge. With this method, it was possible to simultaneously extract the drug compounds in the urine and plasma samples. The enrichment factor and limits of detection (LODs) were obtained in the range of 194-210 and 1.0-2.4 μg L-1,...
Synthesis Of A Stable Triazole-Containing Structure And Compare Its Sorption Capability Versus other Extractive Phases for the Sorption of Triazole Fungicides in Environmental Samples
,
M.Sc. Thesis
Sharif University of Technology
;
Bagheri, Habib
(Supervisor)
Abstract
In this study, a 1,2,3-triazole-containing ligand and the subsequent zinc-based MOF were synthesized. Then, in order to investigate the role of structural similarity of analytes and sorbent on sorption efficiency, the sorption capability of triazole-containing MOF along with several other well-known sorbents toward selected triazole fungicides were tested using dispersive micro solid phase extraction (d-μSPE). In order to further investigate the role of structural similarity on the sorption efficiency, the performance of synthesized MOF in the extraction of other compounds such as triazine herbicides, organochlorine, and organophosphorous pesticides was also evaluated. As expected, the...
Microwave-assisted extraction and high-throughput monolithic-polymer-based micro-solid-phase extraction of organophosphorus, triazole, and organochlorine residues in apple
, Article Journal of Separation Science ; Volume 39, Issue 3 , 2016 , Pages 576-583 ; 16159306 (ISSN) ; Es Haghi, A ; Basiri Pour, F ; Sharif University of Technology
Wiley-VCH Verlag
Abstract
A high-throughput micro-solid-phase extraction device based on a 96-well plate was constructed and applied to the determination of pesticide residues in various apple samples. Butyl methacrylate and ethylene glycol dimethacrylate were copolymerized as a monolithic polymer and placed in the cylindrically shaped stainless-steel meshes of 96-micro-solid-phase extraction device and used as an extracting unit. Before the micro-solid-phase extraction, microwave-assisted extraction was employed to facilitate the transfer of the pesticide residues from the apple matrix to liquid media. Then, 1 mL of the aquatic samples was transferred into the 96-well plate and the 96-micro-solid-phase extraction...
Preparation and evaluation of various banana-based biochars together with ultra-high performance liquid chromatography-tandem mass spectrometry for determination of diverse pesticides in fruiting vegetables
, Article Food Chemistry ; Volume 360 , 2021 ; 03088146 (ISSN) ; Mahdavi, V ; Roustaei, Z ; Bagheri, H ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Biomass, originates from plant- or animal-based materials with a huge potential to be reused. Here we report a simple, rapid and inexpensive method for preparation of modified biochars derived from the banana peel followed by their applications in pipette-tip micro solid-phase extraction (PT-µSPE). Due to the contribution of various effective parameters on modification of banana peel biochars (BPBs), Taguchi design was used to optimize activation temperature, activation repetition, treatment material and impregnation ratio. Efficiency of the prepared BPBs were studied by extraction of twelve various pesticides, as model analytes with an extended range of log P values (1.4–5.7), followed by...
Dispersive micro-solid phase extraction using magnetic nanoparticle modified multi-walled carbon nanotubes coupled with surfactant-enhanced spectrofluorimetry for sensitive determination of lomefloxacin and ofloxacin from biological samples
, Article Materials Science and Engineering C ; Volume 60 , 2016 , Pages 30-36 ; 09284931 (ISSN) ; Pourghazi, K ; Hajjaran, S ; Sharif University of Technology
Elsevier Ltd
Abstract
A dispersive micro-solid-phase extraction (D-μ-SPE) procedure coupled with surfactant-enhanced spectrofluorimetric detection was developed for determination of ofloxacin and lomefloxacin from biological and environmental samples. The D-μ-SPE procedure was performed using magnetic Fe3O4 nanoparticle grafted multi-walled carbon nanotube as an efficient adsorbent. The main factors affecting the signal enhancement (including surfactant concentration and pH) and extraction efficiency (including pH, extraction time, sample volume, amount of magnetic adsorbent, and desorption conditions) were investigated in detail. Under the optimized conditions, the calibration curves were linear (R2 0.9995) over...
An innovative chemometric approach for simultaneous determination of polycyclic aromatic hydrocarbons in oil-contaminated waters based on dispersive micro-solid phase extraction followed by gas chromatography
, Article Microchemical Journal ; Volume 159 , 2020 ; Jabbari, A ; Parastar, H ; Sharif University of Technology
Elsevier Inc
2020
Abstract
In the present study, an analytical strategy was developed using reduced graphene oxide (rGO) as an effective sorbent in dispersive micro-solid phase extraction (DMSPE) for simultaneous determination of seven polycyclic aromatic hydrocarbons (PAHs) combined with gas chromatography (GC-FID). rGO was synthesized using modified Hummer's method and characterized using scanning electron microscope (SEM), atomic force microscope (AFM) and Raman spectroscopy. A rotatable central composite design (CCD) combined with multiple linear regression (MLR) and analysis of variance (ANOVA) was used for designing, modelling and optimization of the extraction procedure. In this regard, principal component...
A stable nitrogen-rich zinc-based metal organic framework to investigate the structural similarity effect on the sorption efficiency of nitrogen-containing compounds
, Article Microchemical Journal ; Volume 170 , 2021 ; 0026265X (ISSN) ; Naderi, M ; Bagheri, H ; Sharif University of Technology
Elsevier Inc
2021
Abstract
A stable porous zinc-based metal organic framework (MOF) containing nitrogen-rich bis-tetrazolate ligand was synthesized to study the role of similar structures concerning both extractive phase and the desired solutes to achieve greater sorption efficiency. With implementing a dispersive micro-solid phase extraction (d-µ-SPE) methodology, the sorption capability and influencing structural parameters i.e., porosity, surface area and interactions types were investigated for the synthesized zinc-bis-tetrazolate (ZnBT) MOF and compared with some synthesized sorbents such as MIL-101, MIL-101-NH2, cadmium naphthalene dicarboxylic acid dimethyl formamide [Cd(NDC)(DMF)], polyaniline and LiChrolut®...
Core-shell electrospun polybutylene terephthalate/polypyrrole hollow nanofibers for micro-solid phase extraction
, Article Journal of Chromatography A ; Volume 1434 , 2016 , Pages 19-28 ; 00219673 (ISSN) ; Rezvani, O ; Banihashemi, S ; Sharif University of Technology
Elsevier B.V
2016
Abstract
In the present work, a new micro-solid phase extraction (μ-SPE) sorbent as an extracting medium based on core-shell nanofibers was synthesized by electrospinning. The core-shell nanofibers of polyvinylpyrrolidone-Polybutylene terephthalate/polypyrrole (PVP-PBT/PPy) were electrospun and subsequently, modified hollow nanofibers were prepared by removing the central PVP moiety. Moreover, conventional PBT/PPy was also prepared for the comparison purposes. The homogeneity and the porous surface structure of the core-shell nanofibers were confirmed by scanning electron microscopy (SEM). The applicability of the fabricated nanofibers-coating was examined by immersed μ-SPE of some selected triazine...
Generic extraction medium: From highly polar to non-polar simultaneous determination
, Article Analytica Chimica Acta ; Volume 1066 , 2019 , Pages 1-12 ; 00032670 (ISSN) ; Khalilzadeh, M ; Bagheri, H ; Sharif University of Technology
Elsevier B.V
2019
Abstract
Sample preparation for non-target analysis is challenging due to the difficulty in the extraction of polar and non-polar analytes simultaneously. Most commercial solid sorbents lack the proper comprehensiveness for extraction of analytes with different physiochemical properties. A possible key is the combination of hydrophobic polymer and hydrophilic surface functional groups in solid based extraction methods in order to generate the susceptibility for retaining both polar and non-polar analytes. To pursue this goal, in this study, four polar groups including [sbnd]NH 2 , [sbnd]NO 2 , [sbnd]COOH, and [sbnd]COCH 3 were chemically bound to Amberlite XAD-4 substrate in order to prepare a...
Graphene oxide-starch-based micro-solid phase extraction of antibiotic residues from milk samples
, Article Journal of Chromatography A ; Volume 1591 , 2019 , Pages 7-14 ; 00219673 (ISSN) ; Behkami, S ; Raoofi, M ; Bagheri, H ; Sharif University of Technology
Elsevier B.V
2019
Abstract
In this study, a method was described for the extraction of three antibiotic residues from cow milk samples using a graphene oxide–starch–based nanocomposite. The prepared nanocomposites were employed as an extractive phase for micro-solid phase extraction of antibiotics from cow milk samples. The extracted antibiotics, i.e. amoxicillin, ampicillin and cloxacillin, were subsequently analyzed by high-performance liquid chromatography–ultraviolet detection (HPLC–UV). Important variables associated with the extraction and desorption efficiency were optimized. High extraction efficiencies for the selected antibiotics were conveniently achieved using the starch–based nanocomposite as the...
Super-porous semi-interpenetrating polymeric composite prepared in straw for micro solid phase extraction of antibiotics from honey, urine and wastewater
, Article Journal of Chromatography A ; Volume 1631 , 2020 ; Bagheri, H ; Es-haghi, A ; Sharif University of Technology
Elsevier B.V
2020
Abstract
A cryogel–based semi–interpenetrating polymer network (Cryo–SIPN) was prepared in which conductive polymers such as polyaniline (PANI) and polypyrrole (PPy) were formed within the super porous network of acrylic acid cryogel. For completion of cryo-polymerization, all the constituent solutions were severely mixed and placed into the plastic straws and kept at -20°C and then the synthesized cyrogels were cut into the 1-cm length and freeze dried after washing with water. The Cryo–SIPN polymeric composite was applied in micro solid phase extraction (µSPE) of some selected antibiotic residues from various samples. The µSPE method combined with a high performance liquid...
Preparation of amine–modified lignin and its applicability toward online micro–solid phase extraction of valsartan and losartan in urine samples
, Article Journal of Chromatography A ; Volume 1643 , 2021 ; 00219673 (ISSN) ; Zeinali, S ; Bagheri, H ; Sharif University of Technology
Elsevier B.V
2021
Abstract
In the present work, with the focus on an environmentally–friendly approach, some gels were prepared by synthesizing amine–modified lignin, extracted from sugarcane bagasse, and further esterification and subsequent freeze–drying. These lignin–based gels were implemented as extractive phases in an online micro–solid phase extraction (μSPE) setup in conjunction with high performance liquid chromatography (HPLC) with UV detector. The developed method was used for analytical determination of valsartan and losartan in urine samples. To study the effect of the functionalization process, the efficiency of the unmodified lignin and the functionalized lignin were compared both in the absence and the...