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High-Throughput Determination of Pesticide Residues by Solid-Phase Microextraction and Micro-Solid Phase Extraction on 96-Well Plate
, Ph.D. Dissertation Sharif University of Technology ; Bagheri, Habib (Supervisor) ; Es-haghi, Ali ($item.subfieldsMap.e)
Abstract
Novel high-throughput device and their applications as the microextraction systems for pesticide multiresidue determination is the centre of this research. 96 extracting unit based on solid phase microextraction and micro-Solid phase extraction were constructed and applied for high-throughput extraction.
In the first work, a high-throughput SPME on 96-well plate together with gas chromatography-mass spectrometry was developed for the determination of pesticide residues in cucumber samples. A home-made Teflon block consisting ninety-six holes was constructed to 96 SPME fibers being positioned in. SPME fibers consisted of stainless steel rods with a 1.0 cm polydimethylsiloxane tubing...
In the first work, a high-throughput SPME on 96-well plate together with gas chromatography-mass spectrometry was developed for the determination of pesticide residues in cucumber samples. A home-made Teflon block consisting ninety-six holes was constructed to 96 SPME fibers being positioned in. SPME fibers consisted of stainless steel rods with a 1.0 cm polydimethylsiloxane tubing...
A Nanocomposite Based on Polyurethane and Cu-TATAB Metal-Organic Framework as a Highly Efficient Sorbent for the Microextraction of Some Chlorinated Pesticides in the Environmental Samples
, M.Sc. Thesis Sharif University of Technology ; Bagheri, Habib (Supervisor)
Abstract
In this research, Cu-TATAB/Polyurethane (PU) nanocomposite fibers were prepared via electrospinning method in order to increase the overall extraction efficiency. The incorporation of Cu-TATAB, as a metal organic framework (MOF), in the synthesized nanocomposite contributed to the enhanced efficiency. The prepared sorbent was implemented for the thin film microextraction (TFME) of organochlorine species and their determination was subsequently performed by gas chromatography-mass spectrometry (GC-MS). To achieve the maximum efficiency of the synthesized sorbent, the parameters of MOF percentage in nanocomposites, solvent type and volume, desorption time, solution ionic strength and...
A high-throughput approach for the determination of pesticide residues in cucumber samples using solid-phase microextraction on 96-well plate
, Article Analytica Chimica Acta ; Volume 740 , 2012 , Pages 36-42 ; 00032670 (ISSN) ; Es'haghi, A ; Eshaghi, A ; Mesbahi, N ; Sharif University of Technology
Abstract
A high-throughput solid-phase microextraction (SPME) on 96-well plate together with gas chromatography-mass spectrometry (GC-MS) was developed for the determination of some selected pesticides in cucumber samples. Pieces with the length of 1.0cm of silicon tubing were precisely prepared and then coated on the end part of stainless steel wires. The prepared fibers were positioned in a home-made polytetrafluoroethylene (PTFE)-based constructed ninety-six holes block to have the possibility of simultaneous immersion of the SPME fibers into the center of individual wells. Pesticides such as diazinon, penconazol, tebuconazol, bitertanol, malathion, phosalone and chlorpyrifos-methyl were selected...
Multiresidue determination of pesticides from aquatic media using polyaniline nanowires network as highly efficient sorbent for microextraction in packed syringe
, Article Analytica Chimica Acta ; Volume 740 , 2012 , Pages 43-49 ; 00032670 (ISSN) ; Alipour, N ; Ayazi, Z ; Sharif University of Technology
Abstract
A simple, rapid and sensitive method based on microextraction in packed syringe (MEPS), in combination with gas chromatography-mass spectrometry (GC-MS) was developed. Polyaniline (PANI) nanowires network was synthesized and used as sorbent of MEPS for the multiresidue determination of selected analytes from triazine, organochlrorine and organophosphorous pesticides in aqueous samples. The PANI nanowires network was prepared using soft template technique and its characterization was studied by scanning electron microscopy (SEM). The presence of micelles in this methodology showed to be an important parameter in shaping the growing polymer. Hexadecyltrimethylammonium bromide (HTAB) was used...
Synthesis and Preparation of Metal Organic Frameworks Based on Metals such as Zinc, Copper, Chromium and Nickel and their Applications in Microextraction Techniques
, Ph.D. Dissertation Sharif University of Technology ; Bagheri, Habib (Supervisor) ; Abbasi, Alireza (Co-Supervisor)
Abstract
The main approach of this thesis is the study of metal- organic frameworks (MOFs) performance as extractive phases in sample preparation methods. Hence, various MOFs were synthesized to investigate the roles of sorbent properties such as surface areas, pore sizes and shapes, interaction types, bonds and building units in extraction procedures of analytes. The prepared sorbents in conjugation with gas chromatography- mass spectrometry (GC-MS) were applied to determination of the environmental pollutants like chlorobenzenes, benzene derivatives (BTEX), polyaromatic hydrocarbons (PAHs) and residues of agriculture herbicides.In the first work, considering studying the roles of the sorbent pore...
Preparation of Nanobiocomposites Based on Halloysite Nanotubes-Zein and Evaluation of their Performance for Thin Film Microextraction
, M.Sc. Thesis Sharif University of Technology ; Bagheri, Habib (Supervisor)
Abstract
In this work, a biocompatible sorbent based on halloysite nanotubes-zein bionanocomposite for direct-immersion thin film microextraction (DI-TFME) is introduced. Zein as a biodegradable, low cost and accessible polymer was used to prepare a flexible thin film with the possession of different interactions and good adsorption capacity. To improve the mechanical and chemical resistance of the film, halloysite nanotubes were combined with zein to prepare the thin film sorbent. The film was used for TFME of 16 pesticides from different chemical classes, including organochlorines and organophosphates followed by gas chromatography with electron capture detector (GC-ECD). To achieve the maximum...
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...
High-throughput micro-solid phase extraction on 96-well plate using dodecyl methacrylate-ethylen glycol dimethacrylate monolithic copolymer
, Article Analytica Chimica Acta ; Volume 792 , August , 2013 , Pages 59-65 ; 00032670 (ISSN) ; Es'haghi, A ; Es-haghi, A ; Mohammadkhani, E ; Sharif University of Technology
2013
Abstract
A novel high-throughput device based on 96-micro-solid phase extraction (96-μ-SPE) system was constructed for multiresidue determination of nine pesticides in aquatic samples. The extraction procedure was performed on a commercially available 96-well plate system. The extraction module consisted of 96 pieces of 1cm×3cm of cylindrically shaped stainless steel meshes. The prepared meshes were fixed in a home-made polytetrafluoroethylene-based constructed ninety-six holes block for possible simultaneous immersion of meshes into the center of individual wells. Dodecyl methacrylate and ethylene glycol dimethacrylate was copolymerized as a monolithic polymer and placed in the cylindrically shaped...
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...
Reinforced polydiphenylamine nanocomposite for microextraction in packed syringe of various pesticides
, Article Journal of Chromatography A ; Volume 1222 , January , 2012 , Pages 13-21 ; 00219673 (ISSN) ; Ayazi, Z ; Es'haghi, A ; Aghakhani, A ; Sharif University of Technology
2012
Abstract
Reinforced polydiphenylamine (PDPA) nanocomposite was synthesized by oxidation of diphenylamine in 4molL-1 sulfuric acid solution containing a fixed amount of carbon nanotubes (CNTs) in the presence of cetyltrimethylammonium bromide (CTAB). The surface characteristic of PDPA and PDPA/CNT nanocomposites was investigated using scanning electron microscopy (SEM). The prepared PDPA/CNT nanocomposite was used as an extraction medium for microextraction in packed syringe (MEPS) of selected pesticides from aquatic environment. The effect of CNT doping level and the presence of surfactant on the extraction capability of nanocomposite was investigated and it was revealed that when 4% (w/w) of CNT in...