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Öğe Development of molecular imprinted polymer based optical sensor for determination of pesticides(Ege Üniversitesi, Fen Bilimleri Enstitüsü, 2017) İlktaç, Raif; Henden, Emür; Aksuner, NurIn this thesis, molecularly imprinted polymers were used in order to investigate the determination of trace levels of 1-naphthol and carbendazim pesticides. In the first chapter of the thesis, four different imprinted polymers were synthesized for the determination of trace levels of 1-naphthol and the polymer with the highest imprinting factor was determined. Optimum pH for 1-naphthol determination was found to be 9 and the polymer capacity was found to be 70.86±7.22 mg/g (n=3). The method was applied to various types of water and quantitative recovery values were obtained. In the second chapter of the thesis, magnetite-molecularly imprinted polymer has been used for the first time in the literature as selective adsorbent before the fluorimetric determination of carbendazim. Optimum working pH for determination of carbendazim with the synthesized polymer was found to be 8 and the capacity of the polymer was found to be 2.31±0.63 mg/g. The proposed method was applied to apple and orange for the determination of carbendazim.Öğe Innovative alginate-clay shell and magnetite-gelatin core composite for multifaceted contaminant removal: Cadmium, thiabendazole and bacterial adsorption from aqueous solutions(Elsevier, 2024) İlktaç, Raif; Bayır, EceIn this study, a novel magnetic composite adsorbent with an alginate-chamotte clay outer layer and a gelatin-magnetite core was synthesised for effective contaminant removal from aqueous solutions. The alginate component ensures biocompatibility, chamotte clay enhances adsorption, gelatin provides mechanical strength, and magnetite enables easy recovery of the adsorbent. The composite material was characterised using Fourier-transform infrared, X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy-energy-dispersive X-ray analysis, micro-computed tomography, Brunauer-Emmett-Teller analysis and dynamic mechanical analysis techniques. Response surface methodology was employed to optimise cadmium and thiabendazole adsorption. Optimal conditions for cadmium removal were achieved at pH 7 using 500 mg of adsorbent, with a 30-min contact time and a 5 mL sample volume. Additionally, thiabendazole adsorption was optimal at pH 3, with a 65-min contact time. Thermodynamic and kinetic experiments revealed that both adsorption processes were spontaneous and endothermic and followed a pseudo-second-order model. Cadmium adsorption aligned with Langmuir isotherm , while thiabendazole adsorption followed Freundlich isotherm . The adsorbent also showed high antibacterial efficiency, effectively removing both Gram-positive S. aureus and Gram-negative E. coli, with adsorption capacities of 43.86 mg g-1 for cadmium, 5.01 mg g-1 for thiabendazole, 2.5 × 1010 CFU g-1 for E. coli and 6.7 × 1010 CFU g-1 for S. aureus. These results highlight the multifunctional potential of the adsorbent for wastewater treatment.Öğe Investigation of metal ion pre-concentration with metal including nano-particles(Ege Üniversitesi, 2011) İlktaç, Raif; Henden, Emür; Erdem Aksuner, NurBu tezde ilk bölümde, FAAS yöntemi ile eser düzeydeki kurşunun, Ni2B (nikel borür) sorbenti kullanarak ön deriştirilmesinin incelenmesi ve tayininin yapılması, ikinci bölümde ise eser düzeydeki Sn(IV)‘ün Ni/NiXB sorbenti kullanarak önderiştirilmesi ve spektroflorometrik olarak tayininin yapılması incelenmiştir. Ni2B sorbentin sulu çözeltilerden eser düzeydeki kurşunun önderiştirilmesinde kullanılması ve Ni/NiXB sorbentinin de Sn(IV)‘ün önderiştirilmesinde kullanılması optimize edilmiştir. Pb(II) tayinleri Alevli Atomik Absorbsiyon Spektrometresi ile Sn(IV) tayinleri ise UV-Vis spektroflorometre ile yapılmıştır. Kullanılan sorbentin Pb(II) için sorpsiyon veriminin çalışılan pH aralığında (pH 5.50-6.00) yüksek olduğu görülmüştür. Ni2B sorbentinin kapasitesi 217 mg Pb(II)/g sorbent olarak bulunmuştur. Sn(IV) için ise çalışılan pH‘da (6.00) Ni/NiXB sorbentinin kapasitesi 6.8mg Sn(IV)/g sorbent olarak bulunmuştur.Öğe Magnetic Hydrogel Beads as a Reusable Adsorbent for Highly Efficient and Rapid Removal of Aluminum: Characterization, Response Surface Methodology Optimization, and Evaluation of Isotherms, Kinetics, and Thermodynamic Studies(Amer Chemical Soc, 2023) İlktaç, Raif; Bayır, EceBiopolymers such as alginate and gelatin have attracted much attention because of their exceptional adsorption properties and biocompatibility. The magnetic hydrogel beads produced and used in this study had a core structure composed of magnetite nanoparticles and gelatin and a shell structure composed of alginate. The combination of the metal-ion binding ability of alginate and the mechanical strength of gelatin in magnetic hydrogel beads presents a new approach for the removal of metal from water sources. The beads were designed for aluminum removal and fully characterized using various methods, including Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy-energy-dispersive X-ray spectroscopy, vibrating sample magnetometry, microcomputed tomography, and dynamic mechanical analysis. Statistical experimental designs were employed to optimize the parameters of the adsorption and recovery processes. Plackett-Burman Design, Box-Behnken Design, and Central Composite Design were used for identifying the significant factors and optimizing the parameters of the adsorption and recovery processes, respectively. The optimum parameters determined for adsorption are as follows: pH: 4, contact time: 30 min, adsorbent amount: 600 mg; recovery time: reagent 1 M HNO3; and contact time: 40 min. The adsorption process was described by using the Langmuir isotherm model. It reveals a homogeneous bead surface and monolayer adsorption with an adsorption capacity of 5.25 mg g(-1). Limit of detection and limit of quantification values were calculated as 4.3 and 14 mu g L-1, respectively. The adsorption process was described by a pseudo-second-order kinetic model, which assumes that chemisorption is the rate-controlling mechanism. Thermodynamic studies indicate that adsorption is spontaneous and endothermic. The adsorbent was reusable for 10 successive adsorption-desorption cycles with a quantitative adsorption of 98.2% +/- 0.3% and a recovery of 99.4% +/- 2.6%. The minimum adsorbent dose was determined as 30 g L-1 to achieve quantitative adsorption of aluminum. The effects of the inorganic ions were also investigated. The proposed method was applied to tap water and carboy water samples, and the results indicate that magnetic hydrogel beads can be an effective and reusable bioadsorbent for the detection and removal of aluminum in water samples. The recovery values obtained by using the developed method were quantitative and consistent with the results obtained from the inductively coupled plasma optical emission spectrometer.Öğe Metal içeren nano-tanecikler ile metal iyonların ön deriştirilmesinin araştırılması(Ege Üniversitesi, 2011) İlktaç, Raif; Henden, EmürBu tezde ilk bölümde, FAAS yöntemi ile eser düzeydeki kurşunun, Ni2B (nikel borür) sorbenti kullanarak ön deriştirilmesinin incelenmesi ve tayininin yapılması, ikinci bölümde ise eser düzeydeki Sn(IV)'ün Ni/NiXB sorbenti kullanarak önderiştirilmesi ve spektroflorometrik olarak tayininin yapılması incelenmiştir. Ni2B sorbentin sulu çözeltilerden eser düzeydeki kurşunun önderiştirilmesinde kullanılması ve Ni/NiXB sorbentinin de Sn(IV)'ün önderiştirilmesinde kullanılması optimize edilmiştir. Pb(II) tayinleri Alevli Atomik Absorbsiyon Spektrometresi ile Sn(IV) tayinleri ise UV-Vis spektroflorometre ile yapılmıştır. Kullanılan sorbentin Pb(II) için sorpsiyon veriminin çalışılan pH aralığında (pH 5.50-6.00) yüksek olduğu görülmüştür. Ni2B sorbentinin kapasitesi 217 mg Pb(II)/g sorbent olarak bulunmuştur. Sn(IV) için ise çalışılan pH'da (6.00) Ni/NiXB sorbentinin kapasitesi 6.8mg Sn(IV)/g sorbent olarak bulunmuştur.;Kurşun, Nikel borür, Alevli Atomik Absorbsiyon Spektrometresi (FAAS), Kalay(IV), Spektroflorometre, Önderiştirme.;Lead, Nickel boride, Flame Atomic Absorption Spectrometry (FAAS), Tin(IV), Spectrofluorometer, Preconcentration.Öğe Moleküler baskılanmış malzemelerin pestisit analizlerine yönelik kullanımı ve LC/Q-TOF/MS ile doğrulama(Ege Üniversitesi, 2020) İlktaç, Raif; Aksuner, Nur; Gümüş, Zinar PınarBu proje kapsamında, manyetik özellikteki moleküler baskılanmış polimerler kullanarak eser miktardaki imidacloprid ve pirimicarb pestisitlerinin analizleri ve doğrulaması LC/Q-TOF/MS ile gerçekleştirilmiştir. Her iki pestisitin analizi için de, çeşitli parametrelerin optimizasyonu gerçekleştirilmiş ve kullanılan baskılanmış polimerlerin karakterizasyonları gerçekleştirilmiştir. Ayrıca her iki pestisit için de çeşitli organik maddelerin girişim etkisi incelenmiştir. Gerçekleştirilen çalışmalarda, sulu ortamlardaki eser düzeydeki pirimicarb tayini için kullanılması gereken minimum adsorban dozunun 15 g/L, geri-bağlama ortamının pH'ı yaklaşık 9 olan su ortamı, geri-bağlama süresinin 15 dakika, geri kazanım süresinin ise 15 dakika olduğu belirlenmiştir. Eser düzeydeki imidacloprid pestisiti için ise kullanılması gereken minimum adsorban dozunun 20 g/L, geri-bağlama ortamının metanol:su (v/v, 50/50), geri-bağlama süresinin 30 dakika, geri kazanım süresinin ise 30 dakika olduğu belirlenmiştir. Manyetik-moleküler baskılanmış polimerlerin (MMIP) karakterizasyonu, ATR-FTIR, SEM-EDS ve VSM cihazları kullanılarak gerçekleştirilmiştir. LC/Q-TOF/MS cihazı kullanılarak yapılan analizlerde pirimicarb için geri-bağlama çalışmalarında çalışma aralığı 5-250 ?g/L, belirtme alt sınırı (LOD) ise 1.22 ?g/L olarak, geri kazanım çalışma aralığı 7.5-250 ?g/L, LOD ise 1.60 ?g/L olarak bulunmuştur. İmidacloprid için ise geri-bağlama çalışmalarında çalışma aralığı 10-500 ?g/L, LOD ise 1.88 ?g/L olarak, geri kazanım çalışma aralığı 10-500 ?g/L, LOD ise 2.33 ?g/L olarak bulunmuştur.;Imidacloprid, pirimicarb, moleküler baskılanmış polimerler, LC/Q-TOF/MS.;Imidacloprid, pirimicarb, molecularly imprinted polymer, LC/Q-TOF/MS.Öğe Pestisit veya ilaç etken maddeleri tayini için moleküler baskılı polimer esaslı optik sensör geliştirilmesi(Ege Üniversitesi, 2017) İlktaç, Raif; Aksuner, NurBu tezde, moleküler baskılanmış polimerler kullanılarak eser düzeydeki 1-naftol ve carbendazim pestisitlerinin tayinlerinin yapılması incelenmiştir. Tezin ilk bölümünde, eser düzeydeki 1-naftol tayinini gerçekleştirmek üzere dört farklı moleküler baskılanmış polimer sentezlenmiş ve baskılama faktörü en yüksek olan polimer belirlenmişir. 1-naftol tayini için optimum çalışma pH'ı 9, polimerin kapasitesi ise 70.86±7.22 mg/g (n=3) olarak bulunmuştur. Yöntem, 1-naftol tayini için çeşitli su örneklerine uygulanmış ve nicel geri kazanım değerleri elde edilmiştir. Tezin ikinci bölümünde ise, florimetrik carbendazim tayini öncesi manyetitmoleküler baskılanmış polimer literatürde ilk defa seçimli adsorban olarak kullanılmıştır. Hazırlanan polimerle carbendazim tayini için optimum çalışma pH'ı 8, polimerin kapasitesi ise 2.31±0.63 mg/g olarak bulunmuştur. Geliştirilen yöntem, elma ve portakaldaki carbendazimi belirlemekte kullanılmıştır.;1-naftol, Carbendazim, Moleküler Baskılanmış Polimer (MIP), Spektroflorometre, Önderiştirme.;1-naphthol, Carbendazim, Molecular Imprinted Polymer (MIP), Spectrofluorometer, Preconcentration.Öğe Selective and sensitive fluorimetric determination of carbendazim in apple and orange after preconcentration with magnetite-molecularly imprinted polymer(Elsevier B.V., 2017) İlktaç, Raif; Aksuner N.; Henden E.In this study, magnetite-molecularly imprinted polymer has been used for the first time as selective adsorbent before the fluorimetric determination of carbendazim. Adsorption capacity of the magnetite-molecularly imprinted polymer was found to be 2.31 ± 0.63 mg g- 1 (n = 3). Limit of detection (LOD) and limit of quantification (LOQ) of the method were found to be 2.3 and 7.8 µg L- 1, respectively. Calibration graph was linear in the range of 10–1000 µg L- 1. Rapidity is an important advantage of the method where re-binding and recovery processes of carbendazim can be completed within an hour. The same imprinted polymer can be used for the determination of carbendazim without any capacity loss repeatedly for at least ten times. Proposed method has been successfully applied to determine carbendazim residues in apple and orange, where the recoveries of the spiked samples were found to be in the range of 95.7–103%. Characterization of the adsorbent and the effects of some potential interferences were also evaluated. With the reasonably high capacity and reusability of the adsorbent, dynamic calibration range, rapidity, simplicity, cost-effectiveness and with suitable LOD and LOQ, the proposed method is an ideal method for the determination of carbendazim. © 2016 Elsevier B.V.Öğe A study of mechanism of nickel interferences in hydride generation atomic absorption spectrometric determination of arsenic and antimony(2011) Henden E.; Işlek Y.; Kavas M.; Aksuner N.; Yayayürük O.; Çiftçi T.D.; İlktaç, RaifStudies have been carried out to clarify the mechanism of nickel interferences in the hydride generation atomic absorption spectrometric determination of arsenic and antimony. The most serious nickel interferences are observed when nickel/nickel boride nanoparticles are produced during NaBH 4 reduction. In this study these particles have been observed to have diameters of less than 40 nm and sorb As(III), As(V) and Sb(III) species rather than arsine and stibine generated as so far assumed. Bulk chemical composition and surface structure of these nanoparticles were studied and it was found that if the NaBH 4 reduction is carried out while passing nitrogen through the solution the black nanoparticles were composed of Ni 2B and, if the reduction is carried out under air the black nanoparticles were found to consist of Ni 3B or possibly a mixture of Ni(0) and Ni 2B. Surface analysis studies with scanning electron microscopy, energy dispersive X-ray spectrometry, X-ray photoelectron spectrometry and X-ray diffraction analysis have shown that the particles have amorphous structure consisting of Ni(0), Ni 2B, Ni 3B and Ni(OH) 2. However, sorption studies have shown that Ni(0) and Ni(OH) 2 do not sorb the analyte ions and arsine and stibine significantly. © 2011 Elsevier B.V. All rights reserved.
