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Öğe Calixarene Nanofiber Design for Human Colon Cancer 3D-Cell Culture(IEEE, 2017) Arpacı, P. Uyar; Özcan, Fatih; Ağaç, Müslüm; Ertul, ŞerefA growing body of evidence has suggested that 3D cell culture systems, in contrast to the 2D systems, represent more accurately the actual microenvironment where cells reside in tissues. Therefore, researchers have concentrated on developing realistic and sophisticated in-vitro 3D cell culture models that actually resemble the complex environment of native tissues. Calixarenes, similar to a ring basket, represent a third generation of supramolecular hosts could be promising candidates in this regard. Due to having a cyclic structure and large surface area, calixarenes, can be functionalized easily with polar and apolar groups, be a good carrier for cations, anions and neutral molecules. Electrospinning of p-tert-butylcalix[4] arene nanofibers with different functional groups were performed and their endothelial (Caco-2) and fibroblastic (L-929) cytocompatibility behaviour on cell adhesion function were examined. Cell attachment kinetics revealed that the (Caco-2) and L-929 attached to the nanofibers functionalized with pyridinumat position 3 at the same rate as to tissue culture plates. In this report, for the first time in literature, it was shown that 3D cultured systems designed with calixarene nanofibers provide excellent in vitro models, allowing the study of cellular responses in a setting that resembles in vivo environments.Öğe Electrospun Nanofibrous Polyacrylonitrile/calixarene Mats: an Excellent Adsorbent for the Removal of Chromate Ions from Aqueous Solutions(SLOVENSKO KEMIJSKO DRUSTVO, 2017) Bayrakcı, Mevlüt; Özcan, Fatih; Yılmaz, Bahar; Ertul, ŞerefHerein, calixarene molecules containing piperidine units at lower rim or upper rim of calix skeleton was turned into a water resistant composite nanofiber adsorbent using polyacrylonitrile (PAN) polymeric support via electrospinning process. The PAN based calixarene nanofibrous adsorbents showed an excellent adsorption capacity toward the toxic chromate anions in aqueous solution. Furthermore, this new nanofiber mats would be promising filter materials for drinking water purification.Öğe Fabrication of Calixarene Based Protein Scaffold by Electrospin Coating for Tissue Engineering(AMER SCIENTIFIC PUBLISHERS, 2018) Çağıl, Esra Maltaş; Özcan, Fatih; Ertul, ŞerefIn this study, calixarene was synthesized by using different functional groups as p-tert-butyl-Calix[4] arene ester and amides. Calixarene nanofibers were produced by electrospin coating. Protein immobilization onto the calixarene nanofibers was carried out with human serum albumin (HSA). The maximum amount of binding on produced three different calixarene nanofibers (DE, 2-AMP and 3-AMP) was compared by using a fluorescence technique for protein analysis. Result showed that maximum binding amount was found to be as 177.85 mg cm(-2) for 3-AMP surface. The protein binding was also characterized by using SEM, TEM, AFM and FT-IR. From obtained results, calixarene-albumin nanofiber was also fabricated by spin coating using 3-AMP which has ability max binding of protein.Öğe Improved Anticancer Efficacy of p-tert-butylcalix[4]arene through Surface Modifications(IEEE, 2017) Arpacı, Pembegül Uyar; Özcan, Fatih; Gök, Emine; Ertul, ŞerefThe search for new potent anticancer drugs that can only target cancer cells, rather than affecting normal tissues is very much commendable. Supramolecular Calixarene (p-tert-butylcalix[4]arene) is a highly promising candidate in this regard and could be modified to enhance preferential cytotoxicity for targeted therapy. Calixarenes are a family of bowl or cone shaped synthetic supramolecular macrocycles, composed of phenol units linked by methylene bridges through and an aldehyde. The proliferation rate of L-929 were observed higher than MCF-7 cells in the Real-Time Cell Analysis (RTCA) Systems. Our research directs that calixarene shows effective preferential cytotoxicity at a concentration range of 25 to 100 mu g/mL with enhanced preferential cytotoxicity shown by the modification of pyridinium group at the position 3 against MCF-7 breast cancer cells. In this present study, the effect of surface altered calixarene by pyridinium groups on preferential cytotoxicity in cancer cell in-vitro by comparing with innate preferential toxicity shown by unaltered. The results reported in this study demonstrated that tumor-preferential in-vitro cytotoxicity of p-tert-butylcalix[4] arene against MCF-7 over L-929 cells present a promising approach for efficient and safe cancer therapy.Öğe Preparation and Application of Calix[4]arene Derivatives Bearing Pyridinium Units-Grafted Magnetite Nanoparticles for Removal of Dichromate and Arsenate Anions(TAYLOR & FRANCIS INC, 2011) Sayın, Serkan; Özcan, Fatih; Yılmaz, MustafaDiamide derivatives of p-tert-butylcalix[4]arene (3a and 3b) have been immobilized onto [3-(2,3-epoxypropoxy)-propyl]-trimethoxysilane-modified Fe3O4 magnetite nanoparticles to obtain D-Calix-GEPPTMS-MNs (4a and 4b) and investigate their sorption capability toward arsenate and dichromate anions at different pH. The novel calixarene derivatives were characterized by a combination of FTIR and H-NMR analyses. The morphology of the magnetic nanoparticles was examined by Transmission Electron Microscopy (TEM) and Thermogravimetric Analyses (TGA). In addition, a simple and versatile method has been used for the determination of arsenate in aqueous solution. In this method, the absorption of the excess dye gradually decreases because of its conversion to colorless carbinol species by combining with methyl violet cation (MV+) and forming stable blue micro particles of (MV+)-molybdoarsenate.Öğe Production of a new platform based calixarene nanofiber for controlled release of the drugs(ELSEVIER SCIENCE BV, 2019) Cağıl, Esra Maltaş; Hameed, Othman; Özcan, FatihThe aim of this study is to develop an electrospun calixarene nanofiber based calixarene for controlled release of hydrophobic drugs. To accomplish this, we have synthesized 5,17-bis[Methyl-N-Methyltranylate]-25,26,27,28-tetrahydroxycalix[4]arene (Compound 3) of which nanofiber (F-14) was produced by electrospinning. The fabricated multilayered electrospun nanofiber was first characterized in terms of morphology and then drug loading and release kinetics were studied in different physiological pH. For this purpose, we have selected two fluorescent drugs which are thiabendazole (Tbz) and donepezil (Dnp) as model drugs to show the usage of the synthesized nanofiber in drug delivery system. Drug loading and release kinetics were monitored by using fluorescence spectroscopy. According to the results, maximum amount of loaded Dnp onto nanofiber was found to be as 30.529 mu g in 20 mM Tris buffer, pH 7.4 end of 120 min. Data showed that loading amount of Tbz onto the nanofiber was measured to be as 1.688 mu g to the 2.25 cm(2) of surface in 20 mM of Tris buffer, pH 7.4 at the end of 120 min. While max release of Dnp from nanofiber was also 9.720 mu g at pH 2.2, that of Tbz from nanofiber was 0.243 mu g at pH 7.4 at the end of 90 min. Drug loading to nanofibers was clarified by SEM, TEM, EDX and FT-IR analysis.Öğe Synthesis and characterization of novel nanofiber based calixarene and its binding efficiency towards chromium and uranium ions(SPRINGER, 2016) Özcan, Fatih; Bayrakcı, Mevlüt; Ertul, ŞerefThe objective of this study is to obtain nanofibrous precursor based calixarene with high ion adsorption capacity by electrospinning of blended solution of polyacrylonitrile (PAN) and upper rim functionalized calix[4]arene bearing N-methylglucamine (Calix-NMG). The obtained electrospun fibers were characterized using fourier transform infrared (FT-IR-ATR), scanning electron microscope (SEM) equipped with energy-dispersive X-ray spectrometry (EDX) and thermogravimetric analyses (TGA and DSC). Analysis indicated that preparation of nanofibers based Calix-NMG was successfully achieved. The ion binding studies exhibited that the nanofiber based Calix-NMG could be efficiently used for the binding of chromate anions and uranium cations. Nanofiber based calix[4]arene with N-methylglucamine chelating groups may be a good candidate as a filter material for treatment of a large quantity of wastewater owing to their very large surface area as well as both the inclusion and donor-acceptor complexation capability of all surfaces associated with the calixarene skeleton.Öğe Synthesis and Evaluation of Chromate and Arsenate Anions Extraction Ability of a N-methylglucamine Derivative of Calix[4]arene Immobilized Onto Magnetic Nanoparticles(ELSEVIER SCIENCE BV, 2010) Sayın, Serkan; Özcan, Fatih; Yılmaz, MustafaIn this study, 5,17-bis-[(N-methylglucamine)methyl]-25,26,27,28-tetrahydroxy-calix[4]arene (3) was synthesized by the treatment of calix[4]arene with a secondary amine N-methylglucamine and formaldehyde. The calixarene derivative (3) was characterized by a combination of FTIR, H-1 NMR and elemental analyses. Followingly, using the macrocyclic building block, the compound 3 was immobilized by [3-(2,3-epoxypropoxy)propyl]trimethoxysilane-modified Fe3O4 magnetite nanoparticles (EPPTMS-MN). The prepared calix[4]arene immobilized material was characterized by a combination of Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and thermogravimetric analyses (TGA). Moreover, the studies regarding the removal of arsenate and dichromate ions from the aqueous solutions were also carried out by using the compound in solid-liquid extraction experiments. It was found that the calix[4]arene-based magnetic material has high extraction ability towards dichromate and arsenate anions in 66% (at pH 1.5) and in 86% (at pH 3.5), respectively.Öğe Synthesis and Oxoanions (Dichromate/Arsenate) Sorption Study of N-methylglucamine Derivative of Calix[4]arene Immobilized Onto Poly[(Phenyl Glycidyl Ether)-co-formaldehyde](SPRINGER, 2010) Sayın, Serkan; Özcan, Fatih; Memon, Shahabuddin; Yılmaz, MustafaThe article describes synthesis as well as the evaluation of sorption properties of new N-methylglucamine substituted calix[ 4] arene and its poly[(phenyl glycidyl ether)-co-formaldehyde] immobilized product. Firstly, 5,17-bis-[(N-methylglucamine)methyl]-25,26,27,28-tetra-hydroxy-calix[4]arene (3) was synthesized by the treatment of calix[4] arene with a secondary amine N-methylglucamine and formaldehyde via Mannich reaction. The immobilization of 3 onto poly[( phenyl glycidyl ether)-co-formaldehyde] to form calixarene based polymer (4) was carried out under suitable reaction conditions via nucleophilic substitution reaction. All the new compounds were characterized by a combination of FT-IR, H-1-NMR spectroscopic and elemental analysis techniques. The sorption studies of 4 reveal that it is an excellent material for the removal of toxic oxoanions especially arsenate from aqueous environment. To understand the selectivity of 4, we also examined the retention of dichromate anions in the presence of Cl-, NO3- and SO42- anions at pH 1.5.Öğe Synthesis of a glutaraldehyde derivative of calix[4]arene as a cross-linker reagent for lipase immobilization(SPRINGER, 2009) Özcan, Fatih; Şahin, Özlem; Yılmaz, MustafaThis article describes the synthesis of a new calix[4]arene 1,3-distal glutaraldehyde derivative 4 as a cross-linker-reagent for immobilization of Candida rugosa lipase (CRL). p-tert-Butylcalix[4]arene 1,3-distal diaminoalkyl derivative (3) synthesized via aminolysis reaction of 5,11,17,23-tert-butyl-25,27-ethoxycarbonylmethoxy-26,28-hydroxycalix[4]arene (2) with 1,8-diaminooctane. Compound 3 was converted to its aldehyde derivative (4) by the treatment with glutaraldehyde solution. 4 was used in lipase immobilization in order to see the role of calix[4]arene binding site on the lipase activity and stability. It was observed that the immobilized lipase activity was maintained at levels exceeding 95% of its original activity after 40 min.Öğe Synthesis of a novel calix[4]azacrown ionophore and its extraction ability toward Cr(VI)(SPRINGER, 2013) Özcan, Fatih; Malkondu, Sait; Koçak, Ahmet; Koçak, Nuriye; Yılmaz, MustafaThe present study describes the synthesis of a novel extractant p-tert-butyl-calix[4]azacrown ionophore (5) and evaluation of its extraction capability toward dichromate ion from aqueous solution. At first, p-tert-butyl-calix[4]azacrown ionophore (5) has been synthesized from the condensation of p-tert-butyl-calix[4]arene diamine (3) with N-(4-formylphenyl)-aza-15-crown-5 (4). The studies regarding the removal of dichromate ion from the aqueous solutions have been carried out in the liquid-liquid extraction systems. The extraction results showed that p-tert-butyl-calix[4]azacrown derivative (5) exhibited generally higher affinity towards dichromate ion than both 3 and 4 at all studied pHs.Öğe Synthesis of Calix[4]arene Bearing Pyridinium Units Supported Silica Gel for Sorption of Arsenate and Dichromate Anions(ELSEVIER, 2010) Sayın, Serkan; Özcan, Fatih; Yılmaz, MustafaIn the present study two new silica gel-immobilized calix[4]arene polymers 4a and 4b have been prepared via modification of calix[4]arene, which contains pyridinium units 3a or 3b with silica-based polymer (ECHES) and investigated their sorption ability towards arsenate and dichromate anions at different pH. The prepared polymers were characterized by Fourier transform infrared spectroscopy, elemental analysis and thermal gravimetric analysis. Finally, the sorption properties of polymers (4a and 4b) towards dichromate and arsenate anions were reported. It was found that these calix[4]arene-based polymers exhibit a high level of sorption abilities towards dichromate and arsenate anions. It was observed that the percentage of arsenate removal reached 62-57% for polymer 4a and 59-50% for 4b when the pH of the aqueous solution was kept in the range of 3.5-4.5. The sorption of arsenate and dichromate anions by calix[4]arenes-based polymers indicates that the partially protonated pyridyl groups play a major role for the formation of hydrogen bonds and electrostatic interactions. In order to fully comprehend the selectivity of 4a, we also examined the retention of dichromate anions in the presence of Cl-, NO3 and SO42- anions at pH 1.5.Öğe Synthesis of Calix[4]arene-Grafted Magnetite Nanoparticles and Evaluation of Their Arsenate as well as Dichromate Removal Efficiency(WILEY, 2010) Sayın, Serkan; Özcan, Fatih; Yılmaz, Mustafa; Tor, Ali; Memon, Shahabuddin; Çengeloğlu, YunusIn this study, 5,17-bis-[(4-benzylpiperidine)methyl]-25,26,27,28-tetrahydroxy-calix[4]arene (3) has been prepared by the treatment of calix[4]arene with a secondary amine (4-benzylpiperidine) and formaldehyde by means of Mannich reaction. The prepared Mannich base (3) has been grafted onto [3-(2,3-epoxypropoxy)-propyl]-trimethoxysilane-modified Fe3O4 magnetite nanoparticles (EPPTMS-MN) in order to obtain 5,17-bis-[(4-benzylpiperidine)methyl]-25,26,27,28-tetrahydroxy calix[4]arene-grafted EPPTMS-MN (BP-calix[4]arene-grafted Fe3O4). All new compounds were characterized by a combination of FTIR and H-1-NMR analyses. The morphology of the magnetic nanoparticles was examined by transmission electron microscopy. Moreover, the studies regarding the removal of arsenate and dichromate ions from the aqueous solutions were also carried out by using 5,17-bis-[(4-benzylpiperidine)methyl]-25,26,27,28-tetrahydroxy-calix[4]arene in liquid-liquid extraction and BP-calix[4]arene-grafted Fe3O4 (4) in solid-liquid extraction experiments. The extraction results indicated that 3 is protonated at proton-switchable binding sites in acidic conditions. Hence, facilitating binding of arsenate and dichromate is resulted from both electrostatic interactions and hydrogen bonding. To understand the selectivity of 3, the retention of dichromate anions in the presence of Cl-, NO3-, and SO42- anions at pH 1.5 was also examined.Öğe Transportation of Cr(VI) through calix[4]arene based supported liquid membrane(ELSEVIER SCIENCE BV, 2013) Solangi, Imam Bakhsh; Özcan, Fatih; Arslan, Gülşin; Ersöz, MustafaThe present study describes a comparative transportation of Cr(VI) across supported liquid membranes (SLMs) containing p-tert-butylcalix[4]arene diamide derivative bearing pyridinium units (3 and 4). These carriers were impregnated onto the supported membrane i.e. Celgard (R) 2500. The impregnated membranes were characterized by using various analytical techniques such as Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FT-IR), Atomic Force Microscopy (AFM) and contact angle measurements. The transport efficiency of 3 and 4 for Cr(VI) from the source to stripping phase has been evaluated. The experiments have been conducted involving the effect of pH, role of NaOH in stripping phase, concentration of Cr(VI), amount of carrier and contact time. Moreover, from the results of stability test, the effect of other co-existing metal ions and field study confirmed the applicability of p-tert-butylcalix[4]arene diamide derivative bearing pyridinium units (4) for the selective recovery of Cr(VI) in the acidic medium. The study also confers its impact on human health, reinstatement of polluted sites and other fields of material science. (C) 2013 Elsevier B.V. All rights reserved.Öğe Two novel calixarene functionalized iron oxide magnetite nanoparticles as a platform for magnetic separation in the liquid-liquid/solid-liquid extraction of oxyanions(ELSEVIER SCIENCE BV, 2013) Sayın, Serkan; Özcan, Fatih; Yılmaz, MustafaThis article focuses on the syntheses of 25,27-bis[3-(N-ethylsulfonic acid)aminopropxy]-26,28-dihydroxy-5,11,17,23-tetra-tert-butyl-calix[4]arene (3) and 25,27-bis[3-(N-ethyl-dihydrogen phosphate)aminopropxy]26,28-dihydroxy-5,11,17,23-tetra-tert-butyl-calix[4]arene (4) as well as their immobilization onto [3-(2,3-epoxypropoxy)-propyl]-trimethoxysilane-modified Fe3O4 magnetite nanoparticles, and the extraction abilities of four new extractants which were characterized by a combination of FTIR, H-1 NMR, elemental analyses, transmission electron microscopy (TEM) and thermogravimetric analyses (TGA) involving electrostatic and hydrogen bonding interactions between the calixarene and oxide anions such as arsenate and dichromate anions. The extraction results indicate that these new calixarene derivatives having high extraction capabilities would be used as effective extractants for the removal of the dichromate/arsenate ions from water. (C) 2013 Elsevier B.V. All rights reserved.Öğe The Use of Calixarene Nanofibers as an HPLC Column Filler(IEEE, 2017) Ali, S. S.; Şen, Nejdet; Durmaz, Fatih; Özcan, Fatih; Ertul, ŞerefThe third generation molecule of supramolecule chemistry, the calixarenes, is superior to the first and second generation molecules, Tac Ethers and Cyclodextrins, due to their ability to be obtained in greater quantities in higher purity and easier to function. The fact that the calixarenne compounds are important in the host-guest chemistry, and that they are ring structures, can carry molecules, anions or cations with advantages such as the absence of molecules [1-3]. In this work, the p-tert-butylcalix[4] arene diester compound was reacted with benzylamine. The structure of the p-tert-butylcalix[4] arene benzylamide molecule obtained as a result of the reaction was elucidated by H-1-NMR and then electrospun nanofibers were used as an HPLC column filler.Öğe Yeni kaliks[4]aren türevlerinin sentezi ve arsenat anyonunun sulardan giderilmesinde kullanılması(Selçuk Üniversitesi Fen Bilimleri Enstitüsü, 2009-07-13) Özcan, Fatih; Yılmaz, MustafaSupramoleküler kimyada daha önceki çalışmalar crown eter ve kriptantlar gibi nötral iyonoforların bazı iyonik moleküllerle iki boyutlu kompleksleri üzerine yoğunlaşmıştı. Son yıllarda halkalı yapıda bir fenol-formaldehit oligomeri olan kaliksarenler crown eterlerde olduğu gibi halkalı yapıda olduklarından katyon, anyon ve nötral moleküllerle seçimli kompleks yapabilmektedirler. Kaliksarenler, crown eter ve kriptantlara göre daha ucuz çıkış maddelerinden kolayca sentezlenmeleri bakımından supramoleküler ve konuk-konak kimyasında vazgeçilmez hale gelmiştir. Kaliksarenler (Gutsche 1989, Böhmer 1995, Gutsche 1995), hidroksil gruplarının orto pozisyonlarından metilen grupları ile bağlı fenil halkalarının siklik dizilişlerinden oluşan, bir metasiklofan sınıfı olarak bilinmektedir.Kaliksarenler, halkalı yapıda olması, kolaylıkla türevlendirilebilmesi ve farklı büyüklükte molekül boşluğu oluşturabilmesi nedeniyle katyon, anyon ve nötral moleküller için iyi birer taşıyıcıdırlar. Bu özelliklerinden dolayı da oldukça geniş uygulama alanına sahiptirler. Bu tez çalışmasında pridil, sülfanat ve fosfat grubu taşıyan farklı p-tert-bütilkalix[4]aren amid türevleri sentezlendi. Başlangıç maddesi olan p-tert-bütil kaliks[4]aren(1), p-ter-bütil fenol ve formaldehitin bazik ortamdaki kondenzasyon reaksiyonu sonucu elde edildi. Bu bileşiğin metilbromasetat ile reaksiyonu sonucu p-tert-bütil kaliks[4]aren(2) diesterleri elde edildi. Bu bileşik sırasıyala 2-aminometil piridin, 3-aminometil piridin, taurine ve 2-aminoetil fosfat ile etkileştirildi. Polimer sentezi için manyetik Fe3O4 nanopartikülleri sentezlendi. Fe3O4 nanopartikülleri epoksipropoksipropil trimetoksisilan ile etkileştirilerek manyetik özellikte silika bazlı polimerler sentezlendi. Sentezlenen bu polimer üzerine pridil grubu (2-aminometil piridin, 3-aminometil piridin ) taşıyan p-tert-bütil kaliks[4]aren (3 ve 4) diamidleri immobilize edildi. Reaksiyonlar İTK ile izlendi, elde elden ürünler kolon kromotografi tekniği ile saflaştırıldı. Sentezlenen bileşiklerin yapıları FTIR, 1H-NMR and elemental analiz spektrofotometreleri ile aydınlatıldı ve bu bileşikler arsenat iyonu için ekstraksiyon çalışmalarında kullanıldı.
