Chemistry / Kimya

Permanent URI for this collectionhttps://hdl.handle.net/11147/4072

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Author: search.filters.author.Eroğlu, Ahmet EminPublisher: search.filters.publisher.Royal Society of Chemistry

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Now showing 1 - 4 of 4
  • Article
    Citation - WoS: 55
    Citation - Scopus: 60
    Development of Molecularly Imprinted Polymers (mips) as a Solid Phase Extraction (spe) Sorbent for the Determination of Ibuprofen in Water
    (Royal Society of Chemistry, 2017) Ölçer, Yekta Arya; Demirkurt, Merve; Eroğlu, Ahmet Emin; Eroğlu, Ahmet Emin; Demir, Mustafa Muammer; 04.01. Department of Chemistry; 03.09. Department of Materials Science and Engineering; 03. Faculty of Engineering; 04. Faculty of Science; 01. Izmir Institute of Technology
    Ibuprofen is a well-known endocrine disrupter. In this study, highly selective molecularly imprinted polymers (MIPs) with different morphologies were synthesized via precipitation and bulk polymerization of methacrylic acid (MAA) and trimethylolpropane trimethacrylate (TRIM) in the presence of ibuprofen as a template. Non-imprinted polymers (NIPs) were also synthesized via the same procedure in the absence of ibuprofen. Spherical and monolithic MIPs were obtained using different experimental conditions, and the spherical MIP was shown to have better sorption towards ibuprofen. The optimum sample pH, sorbent amount, sample volume, and sorption time were determined to be 8.0, 25.0 mg, 10.0 mL, and 30.0 min, respectively. A methanol water mixture (MeOH:H2O, 80:20, pH 3.0) was employed as an eluent with >97% (±0.8, n = 3) desorption. The MIP demonstrated high selectivity towards ibuprofen in the presence of naproxen and ketoprofen. The validity of the proposed method was checked via spike recovery tests using drinking and tap water samples. The method worked efficiently for both water types, resulting in the recoveries of 97.2% (±0.3, n = 3) and 97.7% (±0.2, n = 3).
  • Article
    Citation - WoS: 47
    Determination of Technetium in Sea-Water Using Ion Exchange and Inductively Coupled Plasma Mass Spectrometry With Ultrasonic Nebulisation
    (Royal Society of Chemistry, 1998) Eroğlu, Ahmet Emin; Eroğlu, Ahmet Emin; Leonard, Kinson S.; McCubbin, David; 04.01. Department of Chemistry; 04. Faculty of Science; 01. Izmir Institute of Technology
    An enrichment–separation scheme employing a strong-base type anion-exchange resin was developed for the determination of99Tc in sea-water by inductively coupled plasma mass spectrometry utilising ultrasonic nebulisation with membrane desolvation. Samples were processed through an anion-exchange column to enrich Tc and to eliminate sea-water matrix ions. The limit of detection for 99Tc in sea-water based on processing a 14 ml sample was 0.03 ng l–1. Accuracy was verified with spike recovery experiments. The potential for rapid on-line sample processing via a microcolumn–flow injection system was demonstrated.
  • Article
    Citation - WoS: 16
    Citation - Scopus: 17
    Electrospun Amino-Functionalized Pdms as a Novel Spme Sorbent for the Speciation of Inorganic and Organometallic Arsenic Species†
    (Royal Society of Chemistry, 2013) Boyacı, Ezel; Horzum, Nesrin; Çağır, Ali; Demir, Mustafa Muammer; Eroğlu, Ahmet Emin; Demir, Mustafa Muammer; Eroğlu, Ahmet Emin; 04.01. Department of Chemistry; 03.09. Department of Materials Science and Engineering; 03. Faculty of Engineering; 04. Faculty of Science; 01. Izmir Institute of Technology
    Sol–gel based amine-functionalized SPME fibers (PDMS-weak anion exchanger) were prepared and used for direct mode extraction of dimethylarsinic acid (DMA), monomethylarsonic acid (MMA), and arsenate (As(V)) from aqueous solutions followed by HPLC-ICPMS determination. Two different methods of coating were employed: (i) electrospinning and (ii) dip coating. Electrospinning was used for the first time for preparation of sol–gel based SPME fibers and was found to be superior in terms of extracted amount of arsenicals, coating homogeneity, accessibility of amine groups on the surface, and preparation time for a single fiber. Various parameters such as solution pH, extraction time, agitation speed, extraction temperature, and ionic strength were studied. Optimum extraction conditions were determined as pH of 5.0, extraction time of 30 min, agitation speed of 700 rpm, and extraction temperature of 20 C. Extraction ability of the novel coating decreased by the addition of NaCl as a consequence of the competition between anionic arsenic species and chloride ions for active sites of the weak anion exchanger. This novel sol–gel coating prepared by electrospinning was found to be promising for SPME applications. Vibrational spectroscopy revealed the alignment of PDMS chains by elongational force under electrospinning process. The chain alignment accordingly orients the pendant amino functional groups perpendicular to the fiber surface, which may develop the free active functional groups available to the medium and lead to the enhancement of the extraction performance. Moreover, the proposed coating strategy through electrospinning might be able to break new ground for various applications in analytical chemistry as well as other disciplines.
  • Article
    Citation - WoS: 31
    Citation - Scopus: 32
    Speciation and Preconcentration of Inorganic Tellurium From Waters Using a Mercaptosilica Microcolumn and Determination by Hydride Generation Atomic Absorption Spectrometry
    (Royal Society of Chemistry, 2000) Körez, Aslıhan; Eroğlu, Ahmet Emin; Volkan, Mürvet; Ataman, O. Yavuz; 04.01. Department of Chemistry; 04. Faculty of Science; 01. Izmir Institute of Technology
    A separation–preconcentration method utilising a mercapto-modified silica microcolumn was developed for the determination of trace amounts of Te(IV) and Te(VI) in waters by hydride generation atomic absorption spectrometry. Bottled drinking water, tap water and sea-water samples were spiked with sub-ng ml−1 concentrations of Te(IV) and the spiked solutions were subjected to the mercapto-modified silica microcolumn separation and enrichment procedure. The spike recovery values varied between 86 and 114%. In addition to spike recovery experiments, accuracy was also verified via the analysis of a certified reference material. The limit of detection for Te(IV) in sea-water with a preconcentration factor of 50 was 0.037 ng ml−1. The capability of the microcolumn enrichment scheme for on-line sample processing via flow manifolds was demonstrated. A detailed interference study was performed.