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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...
Gradient Surfaces as New Media in Microextraction Methods
, Ph.D. Dissertation Sharif University of Technology ; Bagheri, Habib (Supervisor)
Abstract
The main idea of this thesis is on the preparation and use of gradian surfaces as extractive phase in the development of microextraction methods in non-targeted analysis.In the first research, a structural gradient of nanoclusters of organoclay-Cu(II) on a copper wire were fabricated by bipolar electrofunctionalization. The headspace in-tube microextraction (HS–ITME) technique was used for the extraction of chlorobenzenes (CBs) as model compounds. The limits of detection (LODs) and linear dynamic range (LDR) were obtained in the range of 0.5-10 and 50-10000 μg L-1, respectively and precision of the method was also obtained (RSD%) in the range of 6-10%. The developed method in this study...
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...
Gradient extractive phase prepared by controlled rate infusion method: An applicable approach in solid phase microextraction for non–targeted analysis
, Article Journal of Chromatography A ; Volume 1574 , 2018 , Pages 130-135 ; 00219673 (ISSN) ; Kazemi, E ; Bagheri, H ; Sharif University of Technology
Elsevier B.V
2018
Abstract
The aim of this study is to introduce an extractive phase based on gradient concept by continuous changing in chemical functional groups for non–targeted analysis. For this purpose, three different two–component coatings containing (3–aminopropyl)trimethoxysilane (APTES) as polar and either phenyltriethoxysilane (PTES), octyl–trimethoxysilane (OTMS) or methyltrimethoxysilane (MTMS) as nonpolar precursors were formed on the modified stainless steel wires using controlled rate infusion (CRI) method. The presence of polar and/or non–polar functional groups on the surface of substrate was evaluated by Fourier–transform infrared spectroscopy (FTIR) together with contact angles determined...