Chemistry / Kimya
Permanent URI for this collectionhttps://hdl.handle.net/11147/4072
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Article Citation - WoS: 55Citation - Scopus: 60Development 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 TechnologyIbuprofen 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).Conference Object Merkezi Laboratuvarların Araştırmadaki Önemi: İyte-mam Örneği(Yükseköğretim Kurulu, 2012) Güden, Mustafa; Akkurt, Sedat; Eroğlu, Ahmet Emin; Demir, Mustafa Muammer; Akkurt, Sedat; Güden, Mustafa; Demir, Mustafa Muammer; 03.09. Department of Materials Science and Engineering; 04.01. Department of Chemistry; 03.10. Department of Mechanical Engineering; 03. Faculty of Engineering; 04. Faculty of Science; 01. Izmir Institute of TechnologyÜniversitelerin üç temel misyonu vardır: bilgiyi üretmek, bilgiyi yaymak ve topluma hizmet etmek. Bunlardan birincisi literatürü takip ederek edinilen bilgi ışığında planlanan deneylerle laboratuvarda güncel veri toplamak ile gerçekleştirilir. İkincisinde, elde edilen güncel veriyi yazılı veya sözlü olarak yayınlayarak bilgiyi yayar. Sonuncusunda ise toplumun bilgi ve birikim bakımından önünde olan üniversite topluma bazı sorunları çözmede katkıda bulunur. Bu çalışmada birinci konu olan veri üretimi ve bunun rasyonalize edilmesi konusunda İzmir Yüksek Teknoloji Enstitüsü (İYTE) Malzeme Araştırma Merkezi (İYTE-MAM) tecrübesi aktarılacaktır. Sanayi firmalarının katma değeri yüksek ürün üretebilmelerinin ön şartı öncelikle kendi ürünlerini geliştirmeleridir. Bunun için de üniversitelerde bulunan ve güncel cihazlarla donatılmış laboratuvarlar büyük önem taşımaktadır. Türk üniversiteleri son yıllarda araştırma makina teçhizat altyapısı bakımından gelişmiş batılı ülkelerin üniversite laboratuvarları ile boy ölçüşecek konuma gelmiştir. Ancak sağlıklı ve güncel veri toplamanın ön şartı deneyimli personel ve verimli bir işletme modeli ile çalıştırılan laboratuvarlarla gerçekleşebilir. Tek disiplinli ve içine kapanık bölüm yapısının dışında çok disiplinli ve farklı bölümlerden araştırmacıları bünyesinde bulunduran merkezler üniversiteden çevresine bilgi akışı köprüsü görevi görmektedir. Türk üniversitelerinde araştırma laboratuvarlarında sıkça rastlanan sorunlar deneyimli teknik personel eksikliği, cihaza erişimde zorluk, cihazın kalibre tutulmaması, teknik desteğin geç gelmesi gibi sıralanabilir. Bu sorunların aşılmasında üniversite çapında ve dışında herkesin kullanımına açık merkez laboratuvar modelinin en etkin çözüm olduğu İYTE-MAM örneğinde geçtiğimiz 10 yılda gözlenmiştir. Bu tür merkez laboratuvarlar randevu sistemiyle çalşarak sanayi firmalarından gelen taleplere hızla cevap verebilmektedir. 2001 yılında kurulan İYTE-MAM kampüste bulunan yüksek maliyetli makina teçhizatı bünyesinde toplayarak malzeme teknolojileri alanında kampüs içi ve kampüs dışında akademik veya sanayi kökenli araştırmacılara randevu sistemiyle hizmet vermektedir.Article Citation - WoS: 16Citation - Scopus: 17Electrospun 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 TechnologySol–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: 70Citation - Scopus: 82Sorption Efficiency of Chitosan Nanofibers Toward Metal Ions at Low Concentrations(American Chemical Society, 2010) Horzum Polat, Nesrin; Boyacı, Ezel; Shahwan, Talal; Shahwan, Talal; Demir, Mustafa Muammer; 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 TechnologyChitosan fibers showing narrow diameter distribution with a mean of 42 nm were produced by electrospinning and utilized for the sorption of Fe(III), Cu(II), Ag(I), and Cd(II) ions from aqueous solutions. The ion concentrations in the supernatant solutions were determined using inductively coupled plasma-mass spectrometry (ICP-MS). The filtration efficiency of the fibers toward these ions was studied by both batch and microcolumn methods. High efficiency in sorption of the metal ions was obtained in the both methods. The effects of sorbent amount (0.10−0.50 mg), shaking time (15−120 min), initial metal ion concentration (10.0−1000.0 μg·L−1), and temperature (25 and 50 °C) on the extent of sorption were examined. The sorbent amount did not significantly alter the efficiency of sorption; however, shaking time, temperature, and metal ion concentration were found to have a strong influence on sorption. By virtue of its mechanical integrity, the applicability of the chitosan mat in solid phase extraction under continuous flow looks promising.