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Adsorption behaviours of lysozyme onto poly-hydroxyethyl methacrylate cryogels containing methacryloyl antipyrine-Ce(III)
(Taylor & Francis As, 2018) Baysal, Zubeyde; Aksoy, Eyyup; Dolak, Ibrahim; Ersoz, Arzu; Say, Ridvan
In this study, Ce3+-based cryogel with methacryloyl antipyrine (MAAP) and 2-hydroxyethyl methacrylic acid (HEMA) [p(HEMA-MAAP-Ce3+] was prepared. MAAP-Ce3+ complex was characterized by UV-near infrared and energy-dispersive X-ray spectroscopy. Cryogel was characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, and swelling test. Pore size of the cryogel was found to be about 30-50 mu m. The effects of flow rate, pH, temperature, and initial enzyme concentration have been investigated. Maximum adsorption capacity was found to be 57.84 mg g(-1) cryogel at pH 6.0. After seven times of adsorption-desorption cycles of same cryogel, it was observed that there is negligible decrease in the adsorption capacity. [GRAPHICS] .
Anoxybacillus sp. SO B1-Immobilized Amberlite XAD-16 for Solid-Phase Preconcentration of Cu(II) and Pb(II) and Their Determinations by Flame Atomic Absorption Spectrometry
(Taylor & Francis Inc, 2015) Oral, Elif Varhan; Ozdemir, Sadin; Dolak, Ibrahim; Okumus, Veysi; Dundar, Abdurrahman; Ziyadanogullari, Berrin; Aksoy, Zehra
A new method for the determination of Cu(II) and Pb(II) by flame atomic absorption spectrometry (FAAS) after preconcentrating on a column containing Anoxybacillus sp. SO B1-immobilized Amberlite XAD-16 was developed. The functional groups of Anoxybacillus sp. SO B1 immobilized on Amberlite XAD-16 were characterized in KBr tablets by Fourier transform infrared (FT-IR) spectrometry. Various parameters such as pH, amount of the adsorbent, eluent type and volume, and flow rate of the sample solution were studied. The optimum pH values of quantitative sorption for Cu(II) and Pb(II) were found to be pH 7.0 and 5.0 and Cu(II) and Pb(II) ions could be quantitatively eluted with 5.0ml of 1.0mol L-1 HCI and 10.0ml of 0.25mol L-1 HNO3, respectively. Recoveries of Cu(II) and Pb(II) were found to be 100.9 +/- 1.57% and 100.3 +/- 0.49% (N = 5), the limits of detection of Cu(II) and Pb(II) in the determination by FAAS (3s, N = 10) were found to be 0.8 and 1.6 mu g L-1, respectively. The proposed enrichment method was applied for metal ion determination from water samples such as two parts of Tigris River water in Diyarbakir and Elazig, Lake of Hazar in Elazig, and tap water in Diyarbakir. Furthermore, the accuracy of the proposed method was verified by studying the analytical recovery and by analyzing certified reference material (NCS-DC 73350 leaves of poplar).
Development of molecular imprinting-based smart cryogels for selective recognition and separation of serum cytochrome-c as a biochemical indicator
(Elsevier Sci Ltd, 2021) Canpolat, Gurbet; Dolak, Ibrahim; Onat, Ruken; Kecili, Rustem; Baysal, Zubeyde; Ziyadanogullari, Berrin; Ersoz, Arzu
The recognition and detection of proteins has an important role in the fields of biochemistry and medicine in term of diagnosis and prognosis. In this study, molecularly imprinted cryogel (MIP) was synthesized for the selective recognition of Cytochrome-c (Cyt-c) by cryopolymerization techniques with the lanthanide-chelate approach using (MAAP)2-Ce(III) as complex functional monomer and Cyt-c as a template protein. The incorporation of template with monomer was characterized by near- infrared (Near-IR) spectroscopy. The binding capacity was optimized in accordance with numerous experimental parameters including pH, initial Cyt-c concentration, flow rate, temperature and ionic strength. As a result, the maximum binding capacity reached to 98.33 mg g-1 in a buffer system with a pH of 6.0. Beside of the excellent reusability performance of prepared MIP, it was successfully applied to separation of template Cyt-c in the existence of hemoglobin (Hb) and myoglobin (Mb) chosen as interfering proteins. The relative selectivity constants of the Cyt-imprinted polymer were determined as 13.84 for the Cyt/Mb pair and 16.05 for the Cyt/Hb pair. Consequently, a high selectivity, simple and cheap strategy for efficient separation of proteins was provided with this novel MIP cryogel.
ICP-MS Determination of Lead Levels in Autopsy Liver Samples: An Application in Forensic Medicine
(Atomic Spectroscopy Press Ltd, 2018) Arica, Enes; Yuksel, Bayram; Yener, Ismail; Dolak, Ibrahim; Gok, Ertugrul; Yilmaz, Eyup
The objective of this study was to develop and validate a senstitive ICP-MS method with no gas mode for the determination of Pb levels in autospy liver samples collected from patients in Diyarbakir, Turkey. The microwave-assisted acid digestion procedure was optimized and applied to accurately weighed dry liver samples. The method showed linearity in the range of 0-100 mu g/kg with a detection and quantification limit of 0.72 mu g/kg and 2.18 mu g/kg, respectively. The calibration graph was characterized with excellent correlation coefficients (r=0.9997) for Pb determination. Certified reference material was used to validate the method in terms of accuracy, precision, and recovery. Good agreement was obtained between the certified values and the measured Pb concentrations. Percent recovery and precision for Pb was calculated at 99.5% and 4.29%, respectively. In the autopsy liver samples, the Pb levels ranged from 106.83 mu g/kg to 1932.08 mu g/kg and the mean Pb levels were found at 375.24 +/- 325.46 mu g/kg. As a result of the statistical analysis, the occupation, smoking habit, settlement, gender, and age appeared to have an effect on the Pb levels in the autopsy liver samples. The procedure described is relatively simple, precise, and applicable for routine toxicological Pb determination in human tissue.
Introduction to Green Sample Preparation
(Royal Soc Chemistry, 2023) Canpolat, Gurbet; Dolak, Ibrahim; Hussain, Chaudhery Ghazanfar; Kecili, Rustem; Hussain, Chaudhery Mustansar
Ion Imprinted Affinity Cryogels for the Selective Adsorption Uranium in Real Samples
(Jihad Daneshgahi, 2019) Dolak, Ibrahim
In this article, selective adsorption of U(VI) in aqueous solutions in the presence various lanthanide ions by using U(VI)-imprinted cryogel polymer was conducted. For this purpose, the prepared pHEMA-(MAH)(3)-U(VI) cryogel polymer by free radical polymerization method. U(VI) was desorbed with 5.0 mol/L HNO3 and thus U(VI)-imrinted were created onto p-HEMA-(MAH)(3) cryogel polymer. To determine the optimum conditions, in the process of selective adsorption of U(VI) ion to U(VI)-imprinted p-HEMA-(MAH)(3) cryogel polymer, some parameters such as pH, flow rate, initial U(VI) concentration were investigated. Under the optimum conditions, the maximum adsorption capacity was obtained as 74.80 mg/g. Selectivity studies were also carried out in the presence of Nd(III), La(III) and Y(III) ions using U(VI)-imprinted p-HEMA-(MAH)(3) cryogel polymer. The obtained adsorption order under competitive conditions was U(VI) > La(III) > Y(III) > Nd(III).
Ion imprinted cryogel-based supermacroporous traps for selective separation of cerium(III) in real samples
(Elsevier, 2018) Kecili, Rustem; Dolak, Ibrahim; Ziyadanogullari, Berrin; Ersoz, Arzu; Say, Ridvan
This study demonstrates the preparation and characterization of a novel ion imprinted cryogel which exhibits high affinity and selectivity towards Ce(III) ions in aqueous solutions and bastnasite ore samples. 2-Hydroxyethyl methacrylate (HEMA) and N-methacryloylamido antipyrine (MAAP) were used as functional monomers for the preparation of Ce(III) imprinted cryogel. The effects of various factors such as initial Ce(III) concentration, flow rate, pH, interaction time and ionic strength on the Ce(III) binding to the prepared ion imprinted cryogels were also studied. The binding equilibrium for Ce(III) is obtained in 30 min at the flow rate of 0.5 mL/min. The maximum binding capacity of the prepared ion imprinted cryogel towards Ce(III) is obtained as 36.58 mg/g at optimum conditions. The selectivity of the prepared ion imprinted cryogel towards Ce(III) in the presence of other possible interfering lanthanide ions such as La(III) and Nd(III) were also performed. The obtained results showed that the prepared ion imprinted cryogel exhibits high selectivity and sensitivity towards Ce(III) ions. The limit of detection (LOD) was found as 50 mu g/L. (C) 2018 Published by Elsevier B.V. on behalf of Chinese Society of Rare Earths.
Ion-Imprinted Polymers for Selective Recognition of Neodymium(III) in Environmental Samples
(Amer Chemical Soc, 2015) Dolak, Ibrahim; Kecili, Rustem; Hur, Deniz; Ersoz, Arzu; Say, Ridvan
This study describes the selective recognition of Nd(III) in aqueous, solutions in the presence of various lanthanide ions by molecularly imprinted polymers. Molecularly imprinted polymers (MIPs) were prepared by suspension polymerization. N-methacryloylamido folic acid (MAFol) was used as the functional monomer. The effects of different variables such as pH, time, and initial Nd(III) concentration on binding characteristics were investigated. Binding, equilibrium time was achieved in 30 min. The maximum binding capacity was found to be 14.6 mg Nd(III) g(-1) polymer. Binding studies of W(III) in the presence of Ce(III), La(III), and Eu(III),ions were also carried out using Nd(III)-imprinted polymers. The imprinted polymers displayed high selectivity toward Nd(III) ions. The obtained binding order under competitive conditions was Nd(III) > La(III) > Ce(III) > Eu(III).
Metal chelate based site recognition of ceruloplasmin using molecularly imprinted polymer/cryogel system
(Taylor & Francis Inc, 2020) Dolak, Ibrahim; Canpolat, Gurbet; Ersoz, Arzu; Say, Ridvan
In the present study, N-Acetylneuraminic acid (NANA)-imprinted poly(2-hydroxyethyl methacrylate-N-methacryloyl-(L)-histidin-Cu(II)) p(HEMA-(MAH)(2)-Cu(II)) has been synthesized by radical polymerization for site recognition of ceruloplasmin. Prepared imprinted cryogel has been characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). When the binding capacity of NANA-imprinted cryogel (MIP) was compared with non-imprinted cryogel (NIP), it was found that MIP has higher adsorption capacity. The maximum amount of binding NANA has found as 83.20 mgg(-1) at pH 7.0 with flow rate of 1 mLmin(-1) at 25 degrees C. Selectivity experiments for MIP and NIP cryogel have been carried out via the NANA/D-mannose and ceruloplasmin/immunoglobulin G (IgG) pair separately and the relative selectivity coefficient (k') has found as 77.46 and 17.97, respectively. Applicable of the MIP in human serum has been studied and resulted successfully.
Molecularly imprinted affinity cryogels for the selective recognition of myoglobin in blood serum
(Elsevier Science Bv, 2018) Dolak, Ibrahim; Kecili, Rustem; Onat, Ruken; Ziyadanogullari, Berrin; Ersoz, Arzu; Say, Ridvan
The present work demonstrates the selective recognition of myoglobin in human serum in the presence of various competitive proteins such as lysozyme, cytochrome c and hemoglobin by using molecularly imprinted affinity cryogels. The imprinted affinity cryogels towards myoglobin were prepared by using cryopolymerization technique. For this purpose, N-methacryloylamido antipyrine (MAAP)-Ce(III) and myoglobin were used as the complex functional monomer and template molecule, respectively. (MAAP)-Ce(III) complex functional in the imprinted cryogel provided a luminescence feature to the cryogel and the detection of the myoglobin was successfully achieved by UV-VIS-Near Infrared (UV-VIS-NIR) Spectroscopy. The effects of some variables such as initial myoglobin concentration, temperature, pH and ionic strength on myoglobin binding to the prepared cryogels were studied. The myoglobin binding capacity of the prepared cryogels was determined to be 68 mgg(-1). Myoglobin binding to the cryogels in the presence of competitive proteins lysozyme, cytochrome c and hemoglobin were also performed. The imprinted cryogels exhibited high selectivity towards myoglobin and the obtained binding order under competitive conditions was myoglobin > lysozyme > cytochrome c > hemoglobin. (C) 2018 Elsevier B.V. All rights reserved.
Multistate proteinous biomemory device based on redox controllable hapten cross-linker
(Elsevier, 2017) Guzel, Remziye; Ersoz, Arzu; Dolak, Ibrahim; Say, Ridvan
A multistate biomemory device consisting of cytochrome c (Cyt-c) photosensitively cross-linked by MACysRu(bipyr)(2)-MACys hapten molecules, which have memory effect through a charge transfer mechanism, has been developed. In this study, it has suggested a highly resolute surface-confined switch composed a signal-enhanced electro-active protein (Cyt-c) co-polymerized on the gold substrates that can be controlled by redox property through Ruthenium based cysteine monomer hapten, MACys-Ru(bipyr)(2)-MACys as an ANADOLUCA photosensitive cross-linker. The photosensitive cross-linking of the Cyt-c protein on the gold surface topography has been determined by the scanning electron microscopy (SEM). Two state memory functions, writing and erasing of the developed biomemory device, have been investigated by the chronoamperometry (CA) and open-circuit potential amperometry (OCPA). The polymeric proteinous memory device, p(MACys-Ru(bipyr)(2)-MACys-coCyt-c) layer, on the gold electrode is stable and repeatable up to with 10(4) times continuous cycle. (C) 2017 Elsevier B.V. All rights reserved.
A new method for preconcentration of Th(IV) and Ce(III) by thermophilic Anoxybacillus flavithermus immobilized on Amberlite XAD-16 resin as a novel biosorbent
(Elsevier Science Bv, 2017) Yener, Ismail; Oral, Elif Varhan; Dolak, Ibrahim; Ozdemir, Sadin; Ziyadanogullari, Recep
A novel approach has been improved for the preconcentration of Th(IV) and Ce(III) by using thermophilic Anoxybacillus flavithermus which were immobilized on Amberlite XAD-16 resin and analyzed by Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES). The concentration of Th(IV) and Ce(III), the eluent type and volume, the pH of model solutions, influences of matrix interference parameters, and flow rate were analyzed and optimized extraction conditions were determined. The optimum pH for quantitative sorption of Th(IV) and Ce(III) was found as 7.0 and elution of Th(IV) and Ce(III) from mini-columns was studied with 1.0 mol L-1, 5 mL HNO3 with recoveries from 100%. The precision of this method was validated by comparing the analytical recovery and certified reference materials (IAEA Soil-7). Finally, this enrichment method was used to determine Th(IV) and Ce(III) in bastnaesite ore sample. (C) 2017 Elsevier B.V. All rights reserved.
A novel lanthanide-chelate based molecularly imprinted cryogel for purification of hemoglobin from blood serum: An alternative method for thalassemia diagnosis
(Elsevier Sci Ltd, 2020) Dolak, Ibrahim; Canpolat, Gurbet; Onat, Ruken; Kecili, Rustem; Baysal, Zubeyde; Ziyadanogullari, Berrin; Ersoz, Arzu
Purification and analyzing of proteins is an essential means for understanding their function and diseases associated with their lack or defect. In this research, a new lanthanide-chelate based molecularly imprinted polymer (MIP) was synthesized for selective separation of Hemoglobin (Hb) from human serum in the presence of various interference molecules. The Hb-imprinted polymer was prepared by using complex functional monomer N-methacryloylamido antipyrine (MAAP)-Ce(III) and 2-Hydroxyethyl methacrylate (HEMA) in accordance of cryopolymerization techniques. The nonimprinted cryogel (NIP) was also prepared at same polymerization conditions in the absence of template Hb molecule. The effects of pH, initial Hb concentration, flow rate, temperature and ionic strength on the binding capacity of both imprinted and nonimprinted cryogels was investigated. The maximum binding capacity for the MIP column was found to be as 79.41 mg g(-1) dry cryogel, that is four times higher than the NIP column under the optimum conditions (pH 5.0, flow rate: 1.0 mL min(-1), T: 25 degrees C). Moreover, selectivity experiments were performed by using two interference proteins as myoglobin (Mb) and cytochrome c (Cyt-c) and the relative selectivity coefficients (k') for Hb/Mb and Hb/Cyt-c pairs were determined as 36.59 and 37.22, respectively.
Preconcentration and determination of copper and cadmium ions with 1,6-bis(2-carboxy aldehyde phenoxy)butane functionalized Amberlite XAD-16 by flame atomic absorption spectrometry
(Elsevier, 2011) Oral, Elif V.; Dolak, Ibrahim; Temel, Hamdi; Ziyadanogullari, Berrin
A new chelating resin, covalently linked 1,6-bis(2-carboxy aldehyde phenoxy)butane with the Amberlite XAD-16 was synthesized and used for preconcentration of Cu(II) and Cd(II) prior to their determination by flame atomic absorption spectrometry (FAAS). It was characterized by elemental analyses and Fourier Transform Infrared Spectroscopy (FT-IR). Cu(II) and Cd(II) ions were quantitatively preconcentrated on minicolumn loaded with synthesised resin at pH 4.00 and 6.00, respectively. They were eluated with 5 mL of 0.5 mol L-1 HCl. Recoveries of Cu(II) and Cd(II) were found to be 100 +/- 2.15, 100 +/- 1.40(N= 5), the limits of detection of Cu(II) and Cd(II) in the determination by FAAS (3s, N= 20) were found to be 0.33 and 1.19 mu g L-1, respectively. The effect of foreign ions on the recovery has been investigated. The proposed method has been applied for the determination of Cu(II) and Cd(II) ions to the real samples collected from Tigris river water in Diyarbakir and Elazig cities in Turkey. Standard addition method and analysis of the certified reference material (NCS-DC 73350) was employed to check the accuracy of the method. (C) 2010 Elsevier B.V. All rights reserved.
Reduction of Cr(VI) in aqueous solutions by natural and roasted pyrite
(Asian Journal Of Chemistry, 2007) Dolak, Ibrahim; Tegin, Ibrahim; Guzel, Remziye; Ziyadanogullari, Recep
In present study, the effects of parameters such as acid concentration of the medium, amount of pyrite, initial Cr(VI) concentration, contact time, temperature and particle size of pyrite on the reduction of Cr(VI) by discontinuous experiments using raw pyrite and the pyrite samples roasted at high temperatures in vacuum were examined. Considering that the pyrite sample converted FeS structure which has much higher reduction ability and is more homogeneous by roasting at high temperatures in vacuum, it was determined that using the pyrite sample in this way for the Cr(VI) reduction was much more efficient.
Removal and Preconcentration of Pb(II), Cr(III), Cr(VI) from the Aqueous Solution and Speciation of Cr(III)-Cr(VI) by Using Functionalized Amberlite XAD-16 Resin with Dithioethylenediamine
(Asian Journal Of Chemistry, 2010) Dolak, Ibrahim; Tegin, Ibrahim; Guzel, Remziye; Ziyadanogullari, Recep
Amberlit XAD-16 was functionalized using dithioethylenediamine as a ligand and characterized by elemental analysis and FTIR spectroscopy. The effects of contact time, pH, electrolyte and the concentration of eluent on separation and preconcentration of Pb(II), Cr(III) and Cr(VI) were studied. In addition, the batch capacity for each ion was determined under the optimum conditions. The preconcentration yields of Pb(II), Cr(III) and Cr(VI) were found to be 96.60 +/- 3.02, 102.20 +/- 3.00 and 100.64 +/- 2.24 %, respectively, with 500 times preconcentration factor under the optimum conditions. The speciation of Cr(III)-Cr(VI) was studied, it was determined that Cr(III) separated in 93.24 +/- 2.21 % yield from the solution containing Cr(III)-Cr(VI) by using Amberlit XAD-16-dithioethylenediamine and Cr(VI) remained in the solution at pH 4, while Cr(VI) separated in 101.43 +/- 3.09 % yield from the solution containing Cr(III)-Cr(VI) and Cr(III) remained in the solution. at pH 7.50 by using Amberlit XAD-16-dithioethylenediamine-Pb(II).
Removal and Preconcentration of Pb(II), V(V), Cr(VI) from the Aqueous Solution and Selective Separation of V(V)-Cr(VI) by Using Functionalized Amberlite XAD-16 Resin with Dithioethylenediamine
(Asian Journal Of Chemistry, 2010) Dolak, Ibrahim; Tegin, Ibrahim; Guzel, Remziye; Ziyadanogullari, Recep
Amberlit XAD-16 was functionalized using dithioethylenediamine as a ligand. and characterized by elemental analysis and FTIR spectroscopy. The effects of contact time, pH, electrolyte and the concentration of eluents on separation and preconcentration of Pb(II), Cr(VI) and V(V) were studied. In addition, the batch capacity for each ion was determined under the optimum conditions. The preconcentration yields of Pb(II), Cr(VI) and V(V) were found to be 96.60 +/- 3.02, 100.64 +/- 2.24 and 98.20 +/- 3.00 %, respectively, with 500 times preconcentration factor under the optimum conditions. The selective separation of Cr(VI)-V(V) was studied in terms of pH. It was determined that V(V) separated in 98.24 +/- 1.21 % yield from the solution containing Cr(VI)-V(V) and Cr(VI) remained in the solution at pH 2.5, while Cr(VI) separated in 101.43 +/- 3.09 % yield from the solution containing Cr(VI)-V(V) and V(V) remained in the solution at pH 8.5 by using Amberlit XAD-16-dithioethylenediamine -Pb(II).
Synthesis and Preconcentration of Amberlite XAD-4 Resin Modified by Dithioethylenediamine
(Asian Journal Of Chemistry, 2009) Dolak, Ibrahim; Tegin, Ibrahim; Guezel, Remziyfe; Ziyadanogullari, Recep
In the present work, Amberlite XAD-4 copolymer resin modified by rubeanic acid was synthesized for separation and preconcentration of Cu(II), Co(II), Ni(II)), Cd (II) and Mn(II). The optimization procedure for analytical parameters including pH, contact time, batch capacity, etc. was examined in order to obtain quantitative recoveries of metal ions. Preconcentration yields of Cu(II), Co(II), Ni(II), Cd (II) and Mn(II) by Amberlite XAD-4-dithioethylenediamine copolymer resin were found as 103.3 +/- 2.6, 96.8 +/- 1.7, 102.0 +/- 3.0, 90.3 +/- 1.7 and 97.2 +/- 2.4 %, respectively. Batch capacity of Cu(II), Co(II), Ni(II), Cd(II) and Mn(II) by Amberlite XAD-4-dithioethylenediamine copolymer resin was determined as 0.1243 +/- 0.0036, 0.2057 +/- 0.0034, 0.2323 +/- 0.0043, 0.1757 +/- 0.0025 and 0.1888 +/- 0.0034 mmol g(-1) resin, respectively. The preconcentration factor was 500 for Cu (II), Co (II), Ni(II), Cd(II) and Mn(II).
The use of magnetic nanoparticles in sample preparation devices and tools
(Elsevier, 2020) Kecili, Rustem; Buyuktiryali, Sibel; Dolak, Ibrahim; Hussain, Chaudhery Mustansar
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