Fatih Ozcan

Synthesis and evaluation of chromate and arsenate anions extraction ability of a N-methylglucamine derivative of calix[4]arene immobilized onto magnetic nanoparticles

In 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, (1)H NMR and elemental analyses. Followingly, using the macrocyclic building block, the compound 3 was immobilized by [3-(2,3-epoxypropoxy)propyl]trimethoxysilane-modified Fe(3)O(4) 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.

Two novel calixarene functionalized iron oxide magnetite nanoparticles as a platform for magnetic separation in the liquid-liquid/solid-liquid extraction of oxyanions.

This 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, (1)H 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.

Synthesis and Preparation of Novel Magnetite Nanoparticles Containing Calix[4]arenes With Different Chelating Group Towards Uranium Anions

In this study, four new magnetite nanoparticle containing different chelating groups as ester, amide and azacrown moieties at the lower rim of calix[4]arenes were prepared by the reaction of formylated calix[4]arenes and amino propyl modified magnetite nanoparticles (APTMS-MN). All of the newly synthesized and prepared compounds were characterized by using different analytical techniques such as nuclear magnetic resonance spectroscopy (NMR), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM) and thermogravimetric analyses (TGA). Furthermore, uranium binding abilities of newly prepared magnetite nanoparticles were evaluated by using solid-liquid phase extraction process and obtained results showed that magnetite nanoparticles containing picolinamide units exhibited superior and more efficient extraction percentage for uranium ions at lower pH values.

Preparation and Application of Calix[4]arene Derivatives Bearing Pyridinium Units-Grafted Magnetite Nanoparticles for Removal of Dichromate and Arsenate Anions

Diamide 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.

Synthesis and characterization of novel nanofiber based calixarene and its binding efficiency towards chromium and uranium ions

The 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.

Humic-makeup approach for simultaneous functionalization of polyacrylonitrile nanofibers during electrospinning process, and dye adsorption study

ABSTRACT A useful methodology is represented to functionalize polyacrylonitrile nanofibers by using humic acid as a makeup agent in electrospinning process. Both morphology and surface chemistry of polyacrylonitrile nanofiber mats were understood to be influenced by incorporation of humic acid into the structure. Physicochemical changes were evidenced by Fourier transform infrared spectroscopy, scanning electron microscope, and surface charge measurements. Unlike some anionic dyes (i.e., methyl orange, methyl red, and Congo red), there was an enhancement in crystal violet (a cationic dye) adsorption after incorporation of humic acid. The Langmuir model fitted well to crystal violet data, and monolayer adsorption capacity was calculated as 81.6 mg/g (r2 = 0.998).

Fabrication of Calixarene Based Protein Scaffold by Electrospin Coating for Tissue Engineering

In 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.

Synthesis of a novel calix[4]azacrown ionophore and its extraction ability toward Cr(VI)

The 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.