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Anthracene excimer-based "turn on" fluorescent sensor for Cr3+ and Fe3+ ions: Its application to living cells
(ELSEVIER SCIENCE BV, 2016) Erdemir, Serkan; Kocyigit, Ozcan
A novel anthracene based fluorescent probe containing benzothiazole group (BFA) was designed and synthesized. The cation binding properties of BFA were studied in the presence of various cations. Both UV-vis and fluorescence spectroscopic studies indicated that BFA was highly sensitive and selective toward trivalent cations (Cr3+ and Fe3+), while there was no response to monovalent, divalent cations and also Al3+ ion. The interaction of BFA with Cr3+ and Fe3+ caused a significant enhancement in emission intensity due to the combination of a unique anthracenyl static excimer formation, the restricted C=N isomerization and the suppression of highly efficient photoinduced electron transfer (PET) process. The detection limits of BFA for Cr3+ and Fe3+ were 0.46 and 0.45 mu M, which presented a pronounced sensitivity toward Cr3+ and Fe3+, respectively. Also, possible utilization of BFA as bioimaging fluorescent probe to detect Cr3+ and Fe3+ in human prostate cancer cell lines was observed by confocal fluorescence microscopy. (C) 2016 Elsevier B.V. All rights reserved.
Bazı kiral ve akiral kaliks[4,6]aren bazlı polimerlerin sentezi ve kolon dolgu maddesi olarak kullanılması
(Selçuk Üniversitesi Fen Bilimleri Enstitüsü, 2011-05-26) Erdemir, Serkan; Yılmaz, Mustafa
u çalışma, bazı kiral ve akiral kalis[4,6]aren bileşiklerinin sentezini, silika bazlı polimerlere immobilize edilmesini ve bu polimerlerin HPLC de kolon dolgu maddesi olarak kullanılmasını içermektedir. Başlangıç maddeleri olarak p-ter-butilkaliks[4]aren (1) ve p-ter-butilkaliks[6]aren (22) literatüre göre sentezlendi. Daha sonra, bileşik 1'in t-bütil grupları AlCl3/fenol ortamında giderildikten sonra, metil bromasetat ve tetraetilenglikolditosilat ile etkileştirilerek kaliks[4]aren'in crown-5 diester (4) türevi elde edildi. Elde edilen bileşik 4, 3-aminopropil silika jel yüzeyine toluen ortamında immobilize edilerek CIMS-1 hazırlandı. Diğer sentez çalışmasında ise 1,3-konformasyonuna sahip kaliks[4]aren'in ftalimit ve propil/oktil grupları bulunduran bileşik 7 ve 8 hazırlandı. Bu bileşiklerin ftalimit grupları etanol ortamında NH2NH2.H2O ile hidrolizlendi ve böylece bileşik 9 ve 10 elde edildi. Daha sonra elde edilen bileşik 9 ve 10'un 3-kloropropil silika jel ile asetonitril ortamında etkileştirilmesiyle CIMS-2 ve CIMS-3 polimerleri elde edildi. Ayrıca p-Ter-bütilkaliks[6]aren 22 bir diğer başlangıç maddesi olarak sentezlendikten sonra, metil bromasetat ile etkileştirilerek hekzaester türevi 23 sentezlendi ve LiAlH4 ile indirgenerek p-tert-bütilkaliks[6]arenin hekzaalkol türevine 24 dönüştürüldü. Daha sonra, bileşik 24, 3-kloropropil silikajel yüzeyine immobilize edilerek CIMS-6 polimeri elde edildi. Kiral özellikteki iki farklı kaliks[4]aren türevi için metil bromasetat ile p-ter-bütilkaliks[4]aren'in (1) diester 13 ve tetraester 17 türevleri sentezlendi. Daha sonra, 13 ve 17 numaralı bileşikler (R)-(+)-1-feniletilamin ile toluen:metanol karışımında etkileştirilerek kiral di-amit 14 ve tri-amit türevlerine 19 dönüştürüldü. CIMS-4 and CIMS-5 polimerleri 14 ve 19 bileşiklerinin 3-aminopropil silikajel üzerine immobilize edilmesiyle hazırlandı. Sentezlenen kaliksaren türevleri ve silika polimerlerinin yapıları NMR, FT-IR, termal ve elemental analiz teknikleri ile aydınlatıldı. Hazırlanan polimerlerin bazı kiral ilaçlar, bazı aromatik hidrokarbonlar, aminler ve fenolik bileşiklerin ayrılmasında sabit faz olarak kullanılması incelendi.
Calix[4]arene derivative bearing imidazole groups as carrier for the transport of palladium by using bulk liquid membrane
(ELSEVIER SCIENCE BV, 2012) Akın, İlker; Erdemir, Serkan; Yılmaz, Mustafa; Ersöz, Mustafa
The carrier activity of calix[4]arene containing imidazole groups towards the facilitated transport of palladium(II) through dichloromethane bulk liquid membrane has been studied. The optimum transport conditions were established by the studies on the effect of pH, feed concentration, carrier concentration, receiver phase concentration and transport time. A solution of 1 M hydrochloric acid (HCl) served as receiving phase for maximum transport of the metal ion. Maximum transport efficiency was observed for Pd(II) ion when it was present in the concentration of 10(-3) M and the transport efficiency after 24 h was found as 95%. (C) 2012 Elsevier B.V. All rights reserved.
Calixarene-based receptors for molecular recognition
(SCIENTIFIC TECHNICAL RESEARCH COUNCIL TURKEY-TUBITAK, 2013) Yılmaz, Mustafa; Erdemir, Serkan
Calixarene-based molecular receptors have been a widely developing area in material science and technology for the last few decades. Due to their bowl-shaped geometry, calixarene macrocycles are used as hosts allowing organic and inorganic guests to coordinate/sorb onto their cavity. This work briefly reviews the recent development of calixarenes.
Carcinogenic direct azo dye removal from aqueous solution by amino-functionalized calix[4]arenes
(SPRINGER, 2015) Akceylan, Ezgi; Erdemir, Serkan
This study contains a convenient synthesis and azo dye extraction efficiency of amino-functionalized calix[4]arene derivatives. Two calix[4] arene derivatives bearing alkyl amino groups on their upper and lower rim have been successfully synthesized and used as extractant for dye removal in liquid-liquid extraction system. The effect of electrolyte concentration, contact time, and pH on azo dye extraction was also investigated for all calixarene derivatives. From the results, it has been deduced that the amino-functionalized calix[4]arenes showed a better affinity than other parent calix[4]arenes towards the selected azo dyes.
Catalytic effect of calix[n]arene based sol-gel encapsulated or covalent immobilized lipases on enantioselective hydrolysis of (R/S)-naproxen methyl ester
(SPRINGER, 2012) Erdemir, Serkan; Yılmaz, Mustafa
In this paper the catalytic performance of the immobilized lipases was investigated in the presence of calixarene based polymers using different immobilization techniques. For this reason, Candida rugosa lipase was encapsulated in sol-gel matrices using alkoxysilane precursors and calix[n]arene based silica polymers as additives. The hydrolytic activities of encapsulated lipases were evaluated and compared with the free lipase and covalently immobilized lipases (CnP-L). These encapsulated lipases were also used in the kinetic resolution of the R/S-Naproxen methyl ester. The results indicated that the C6P encapsulated lipase has significantly higher conversion and enantioselectivity as compared to the free lipase; other encapsulated lipases and CnP-L. The optimal pH and temperature region of the C6P encapsulated lipase in the kinetic resolution of the R/S-naproxen methyl ester were 7.0 and 55 A degrees C. Nevertheless, the encapsulated lipases have good stability, adaptability and reusability in comparison with the free enzyme.
Coumarin Based Highly Selective "off-on-off" Type Novel Fluorescent Sensor for Cu2+ and S2- in Aqueous Solution
(SPRINGER/PLENUM PUBLISHERS, 2017) Karuk Elmas, Aukriye Nihan; Ozen, Furkan; Koran, Kenan; Yilmaz, Ibrahim; Gorgulu, Ahmet Orhan; Erdemir, Serkan
Solvent free synthesis of 6,7-dihydroxy-3-(3-chlorophenyl) coumarin (CFHC) was designed and obtained by the interaction of 2-(2,4,5-trimethoxyphenyl)-1-(3-chlorophenyl)acrylonitrile with pyridinium hydrochloride in the presence of silica gel by using microwave irradiation. The characterization of CFHC was confirmed by FT-IR, H-1, C-13, C-13-APT and 2D HETCOR spectroscopy methods. The optical behavior of CFHC towards metal ions was investigated by UV-visible and fluorescence spectroscopy. CFHC showed "on-off" type fluorescence response towards Cu2+ with high selectivity in aqueous solution (CH3CN/H2O, 9/1, v/v). Once binding with Cu2+, CFHC-Cu2+ complex also displayed high selectivity for sulfide, resulting in "off-on" type sensing of sulfide anion.
A cyanobiphenyl containing fluorescence "turn on" sensor for Al3+ ion in CH3CN-water
(ELSEVIER SCIENCE SA, 2015) Alici, Onder; Erdemir, Serkan
A novel fluorescent sensor, 4'-hydroxy-3'-(((2-hydroxyphenyl)imino)methyl)-4-biphenylcarbonitrile (AAF) was synthesized and characterized by combination of H-1, C-13, APT, COSY NMR, FT-IR, and elemental analysis. The behaviors of the receptor AAF toward different metal ions were determined by UV-vis and fluorescence spectroscopy. The receptor AAF exhibited a 24-fold increase in fluorescence intensity in the presence of Al3+ over most other competitive metal ions in CH3CN-water (v/v, 1/1). (C) 2014 Elsevier B.V. All rights reserved.
Detection of Hg2+ ion in aqueous media by new fluorometric and colorimetric sensor based on triazole-rhodamine
(ELSEVIER SCIENCE SA, 2015) Erdemir, Serkan; Kocyigit, Ozcan; Malkondu, Sait
A highly efficient and selective rhodamine B sensor bearing triazole unit (RHT) as the metal ion receptor was designed and synthesized. RHT was characterized by H-1 NMR, C-13 NMR, APT COSY, FTIR, elemental analysis, and also its binding selectivity toward various metal ions was studied. Fluorescence enhancement by factors 24 times was achieved upon selective interaction with Hg2+ ion over other metal ions in aqueous solutions. Selective fluorescent enhancement of RHT was attributed to ring opening from the spirolactam (nonfluorescent) to ring-opened amide (fluorescent). Also, distinct color changes from colorless to pink provided "naked eye" detection of Hg2+. (C) 2015 Elsevier B.V. All rights reserved.
Dual recognition of Zn2+ and Al3+ ions by a novel probe containing two fluorophore through different signaling mechanisms
(ELSEVIER SCIENCE SA, 2018) Erdemir, Serkan; Kocyigit, Ozcan
A new reactive and highly selective fluorescent sensor (CBA) containing 4-cyanobiphenyl and anthracene as two fluorophores was synthesized for the detection of Zn2+ and Al3+ ions. CBA exhibited an effectively selective and sensitive recognition towards Zn2+ and Al3+ ions through two different mechanisms (i.e. PET, C = N isomerization and hydrolysis) in EtOH-H2O (v/v = 95/5) over other cations. The complexation properties of CBA with Zn2+ and Al3+ ions were examined by UV-vis, H-1 NMR and FTIR experiments. This sensor showed high sensitivity for Zn2+ and Al3+ with detection limits (LOD) as low as 78.8 and 52.2 nM, respectively, and high selectivity through a 'turn-on' fluorescence response over the other tested metal ions. To check its applicability, an easy prepared test paper strip of CBA was produced for rapid and selective detection of Zn2+ and Al3+ ions. Also, the determination of Zn2+ and Al3+ in water samples was evaluated.
Dual-channel fluorescent probe based on bisphenol A-rhodamine for Zn2+ and Hg2+ through different signaling mechanisms and its bioimaging studies
(ELSEVIER SCIENCE SA, 2017) Erdemir, Serkan; Yuksekogul, Mesut; Karakurt, Serdar; Kocyigit, Ozcan
A novel dual channel probe based on bisphenol A-rhodamine (BAR) was successfully designed and synthesized with high selectivity and sensitivity to Zn2+ and Hg2+ ions. BAR exhibited an effectively selective and sensitive recognition toward Zn2+ and Hg2+ ions through two different mechanisms (i.e. ESIPT and FRET) in pure MeCN and MeCN-H2O (v/v = 8/2, 5 mM, HEPES, pH 7.0) over other cations. The complexation properties of BAR with Zn2+ and Hg2+ ions were examined by H-1 NMR, C-13 NMR and FTIR experiments. The detection limits for Zn2+ and Hg2+ were 2.21 and 2.16 mu M, respectively. Furthermore, possible utilization of BAR as bio-imaging fluorescent probe to detect Hg2+ in human prostate cancer cell lines was ;also observed by Fluorescent Cell Imager. (C) 2016 Elsevier B.V. All rights reserved.
Effect of the glutaraldehyde derivatives of Calix[n]arene as cross-linker reagents on lipase immobilization
(SPRINGER, 2009) Erdemir, Serkan; Şahin, Özlem; Uyanık, Arzu; Yılmaz, Mustafa
Synthesis of the glutaraldehyde derivatives calix[n]arene (n = 4,6,8) (Calix[n]-GA) and using as cross-linkers for immobilization of Candida rugosa lipase (CRL) have been discussed in this paper. The amino functional calix[n]arene derivatives (Calix[n]-NH (2)) were synthesized via reduction of dinitrile, hexanitrile and octanitrile derivatives of calix[n]arenes. These amino functional calix[n]arene derivatives (Calix[n]-NH (2)) were converted to their aldehyde derivativatives with glutaraldehyde. The calix[n]arene derivatives were used in lipase immobilization in order to see the role of calix[n]arene binding site on the lipase activitiy and stability. The activity recovery of calix[n]arene-supported lipases (Calix[n]-CRL) based on the Calix[4]-CRL, Calix[6]-CRL and Calix[8]-CRL reaches to 53.5, 66.1 and 76.4%, respectively.
Enantioselective hydrolysis of (R/S)-Naproxen methyl ester with sol-gel encapculated lipase in presence of calix[n]arene derivatives
(ELSEVIER SCIENCE BV, 2009) Şahin, Özlem; Erdemir, Serkan; Uyanık, Arzu; Yılmaz, Mustafa
Lipases are enzymes that catalyses a variety of reactions, such esterifications, interesterification and hydrolysis. Several methods have been reported for the immobilization of lipases, such as deposition onto solid supports, covalent binding and encapsulation within a polymer matrix or silica glasses obtained by sol-gel techniques. In this study, the Candido rugosa lipase was encapsulated within a chemically inert sol-gel support prepared by polycondensation by tetraetoxysilane (TEOS)and octyltrietoxysilane(OTES) in the presence and absence of calix[n]arene, calix[n]-NH2 and calix[n]-COOH (n = 4,6,8) compounds as additives. The catalytic activity of the encapsulated lipases was evaluated into model reactions, i.e. the hydrolysis of p-nitrophenylpalmitate (p-NPP), and the enantioselective hydrolysis of rasemic Naproxen methyl ester that was studied in aqueous buffer solution/isooctane reaction system. The results indicated that the particularly calix[4,6]-NH2 and calix[6]-COOH based encapsulated lipases had higher conversion and enantioselectivity compared to the sol-gel free lipase. (C) 2009 Elsevier B.V. All rights reserved.
Evaluation of the Chromatographic Performance of di-and tri-amide Calix[4]arene Derivatives Bonded Silica Stationary Phases
(TAYLOR & FRANCIS INC, 2012) Erdemir, Serkan; Yılmaz, Mustafa
The chromatographic behaviors of di- and tri-amide derivatives of calix[4]arene immobilized onto aminopropyl silica gel (Calix-SP1 and Calix-SP2) were evaluated by using some aromatic hydrocarbons and aromatic amines in the HPLC. The effect of organic modifier content, pH and column temperature on retention and selectivity of these compounds were investigated. The results of the study of column temperature influence have shown a high linear correlation between the logarithm of capacity factor and reciprocal value of absolute temperature for each studied analyte. The thermodynamic parameters implicated in chromatographic retention were determined using the van't Hoff method. The retention mechanism was also discussed. The results indicated that the stationary phases behave like a reversed-phase packing. However inclusion, hydrophobic, hydrogen bonding, and pp interactions seem to be involved in separation process.
Extraction of carcinogenic aromatic amines from aqueous solution using calix[n]arene derivatives as carrier
(ELSEVIER SCIENCE BV, 2009) Erdemir, Serkan; Bahadır, Müfit; Yılmaz, Mustafa
The extraction abilities of p-tert-butylcalix[n]arenes (n = 6, 8) and their carboxylic acid and methyl ester derivatives upon some carcinogenic aromatic amines have been investigated. The separation and quantification of aromatic amines were performed by high-performance liquid chromatography with Ace 5 C-18 column and diode array detection. The optimum pH values for aromatic amines sorption were observed at pH 4.0, 7.0 and 8.5 for all calixarene derivatives. In batch sorption experiments of selected carcinogenic aromatic amines, the experimental results show that octacarboxylic acid derivative of p-tert-butylcalix[8]arene exhibited a better affinity than other compounds towards all aromatic amines species at almost all pHs. The sorption of aromatic amines by carboxylic acid derivatives of p-tert-butylcalix[n]arene indicates that carboxyl groups play the major role for the formation of hydrogen bonds and electrostatic interactions between sorbent and aromatic amine. (C) 2009 Elsevier B.V. All rights reserved.
Fast and reversible "turn on" fluorescent sensors based on bisphenol-a for zn2+ in aqueous solution
(SPRINGER/PLENUM PUBLISHERS, 2019) Tabakci, Begum; Ahmed, Hayder Mahdi Ahmed; Erdemir, Serkan
Two novel bisphenol-A derivatives (R1 and R2) linked pyrene and napthylthiazole moieties were synthesized via condensation reaction, and positively applied for the selective recognition of Zn2+ ion in EtOH/H2O. Their optical properties were observed by using UV-vis and fluorescence measurements. R1 and R2 exhibited high selectivity and sensitivity towards Zn2+ over other metal ions. This fluorescence selectivity may be owing to inhibited excited-state intramolecular proton transfer (ESIPT) and photoinduced electron transfer (PET). The fluorescence titration analysis indicated detection limits of R1 and R2 for Zn2+ at 17.5 nM and 0.94 mu M, respectively. Moreover, R1 and R2 were successfully applied to the detection of Zn2+ with different concentrations in water samples.
Fluorogenic Recognition of Zn2+, Al3+ and F- Ions by a New Multi-Analyte Chemosensor Based Bisphenol A-Quinoline
(SPRINGER/PLENUM PUBLISHERS, 2015) Erdemir, Serkan; Kocyigit, Ozcan; Malkondu, Sait
A new available multi-analyte fluorescent sensor based on a bisphenol A-quinoline conjugate (BFQ) was synthesized in two facile steps and was characterized systematically. BFQ exhibited an effectively selective and sensitive recognition toward Zn(2+)and Al3+ cations in EtOH-H2O (v/v = 9/1) over other cations and F- anion in CH3CN over other anions with remarkably enhanced fluorescent intensities. According to the quantum yield (I broken vertical bar) measurements, BFQ-Zn2+, BFQ-Al3+ and BFQ-F- complexes showed 16, 22 and 30 times higher I broken vertical bar values than BFQ, respectively. The complexation properties of BFQ with Zn2+, Al3+ and F- ions were also examined by H-1 NMR titration experiments.
A highly selective and sensitive benzothiazole-based 'turn-on' fluorescent sensor for Hg2+ ion
(WILEY, 2015) Erdemir, Serkan; Malkondu, Sait; Alici, Onder
A simple benzothiazole-based fluorescent probe (TDA) for the determination of Hg2+ ion in aqueous solutions was synthesised in one step and characterised by H-1 NMR, C-13 NMR, APT, COSY, FTIR, and elemental analysis. TDA shows a significant fluorescence change upon the interaction of Hg2+ ion in DMF-water (v/v=1/1), while only minor changes in fluorescence intensity are observed with 18 other metal ions. Fluorescence enhancement by a factor of 15 is achieved upon selective interaction with Hg2+ ion. The Hg2+ ion detection process is found to be pH dependent; therefore, TDA could be feasible within a pH range of 4.0-7.0.
A highly selective fluorescent sensor based on calix[4]arene appended benzothiazole units for Cu2+, S2- and HSO4- ions in aqueous solution
(ELSEVIER SCIENCE SA, 2016) Erdemir, Serkan; Tabakci, Begum; Tabakci, Mustafa
A novel calix[4]arene receptor containing benzothiazole units in 1,3-alternate conformation (L) was synthesized and characterized by H-1, C-13, APT, COSY NMR, FTIR, elemental analysis, and UV-vis spectral data. The cation and anion binding properties of L were investigated in the presence of various cations and anions. L showed "on-off' type fluorescence response towards Cu2+ with high selectivity in aqueous solution (CH3CN/H2O, 4/1, v/v). Once binding with Cu2+, L-Cu2+ complex displayed high selectivity for sulfide. Among the various anions, only sulfide anion induced the revival of fluorescence of L, resulting in "off-on" type sensing of sulfide anion. Furthermore, L served exclusive response towards HSO4- ion via hydrolysis process with 10-fold fluorescence enhancement at 542 nm. (C) 2016 Elsevier B.V. All rights reserved.
Highly sensitive fluorometric detection of Zn2+ ion by calix [4] arene derivative appended 4-biphenylcarbonitrile
(ELSEVIER SCI LTD, 2018) Erdemir, Serkan; Tabakci, Begum
A novel calix[4]arene derivative bearing 4-biphenylcarbonitrile unit (CCP) was developed for the selective fluorescent sensing of Zn2+ with a discriminating enhancement of 14-folds over the other metal ions. CCP exhibited highly selective and sensitive fluorescence "off-on" recognition to Zn2+ with a 1:1 binding stoichiometry in aqueous solution (EtOH/H2O, 8/2, v/v). The binding constant was calculated as 3.50 x 10(5) M-1 with detection limit of 0.31 mu M, which presented a pronounced sensitivity toward Zn2+ ion. To check its applicability, an easy prepared test paper strip of CCP was made for rapid and selective detection of Zn2+. Also, the determination of Zn2+ in water samples was evaluated. Otherwise, the results demonstrated that the binding between CPP and Zn2+ is chemically reversible in presence of only cysteine among the various amino acids and anions, resulting in "on-off" type sensing of cysteine.

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