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Öğe An effective and facile approach for the determination of bioactive components of Rheum ribes in the Kurdish state of Iraq and Siirt region in Turkey(National Library of Serbia, 2025) İbrahim Tegin; Bakhtiyar Mahmood Fattah; Mehmet Fidan; Orhan Acar; Erdal YabalakDeveloping a streamlined and accessible method for identifying the bioactive components of Rheum ribes (rhubarb) holds significant promise in unlocking its therapeutic potential and advancing research in natural medicine. In this study, the bioactive components of rhubarb such as total phenolics and flavonoids as well as the antioxidant activity of its methanolic extract were determined. Total phenolic content was between 84.02 and 387.53 mg/L gallic acid equivalent (GAE) in extracts. Total flavonoid contents determined by the aluminium chloride colorimetric method ranged from 69.98 to 935.75 mg L-1 of routine equivalents (RE) in the extracts. The antioxidant activities were determined using ferric reducing the antioxidant potential (FRAP) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) methods. In the FRAP assay, the highest antioxidant activity (IC50) was found as 25.18±0.04 mg L-1 extract. In the DPPH method, the maximum percentage inhibition was found as 88.11 %. Iron chelating activities of the samples were above 70 %. The chemical compound contents of the extracts were determined by LC-MS/MS. In this step, a total of 25 phenolic and flavonoid compounds in extracts were analysed qualitatively and quantitatively. Malic acid (15.72±0.53 mg kg-1) and rutin (76.93±0.03 mg kg-1) in the extract were identified as the major phytochemicals compounds. The results of the study confirm that rhubarb have potential biological activities and can be introduced as an important sources of natural antioxidants.Öğe Cost-Effective Removal of Cu(II) and Cd(II) from Wastewater Using Walnut Shell-Immobilized Amberlite XAD-4 as a Sorbent(Springer Science and Business Media LLC, 2025-05-19) İbrahim Teğin; Selma Akdeniz; Gurbet Canpolat; Orhan AcarIn this study, a cost-effective and environmentally friendly solid-phase extraction (SPE) method using walnut shell-immobilised on Amberlite XAD-4 (WNS-XAD-4) was developed to pre-concentrate and determine Cu(II) and Cd(II) ions in water samples prior to flame atomic absorption analysis (FAAS). The low-cost adsorbent, prepared by immobilizing waste walnut shells on Amberlite XAD-4 (WNS-XAD-4), was characterized using Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Thermal Gravimetric Analysis (TGA), and Brunauer-Emmett-Teller (BET) analysis. Under optimal conditions, the method achieved recoveries of 95.7% for Cu(II) and 100% for Cd(II) using 5.0 mL of 1.5 mol L-1 HNO3 as eluent. The detection limits were found as 0.582 mu g L-1 for Cu(II) and 0.03 mu g L-1 for Cd(II) with preconcentration factors of 10 and 40, respectively. The accuracy of the method was validated using the certified aquatic plant reference material BCR-670 and successfully applied to various real water samples, including those from Lake Van, Billoris Spa, tap water, salt water and wastewater from Siirt, Turkey.Öğe Dynamical analysis of fractional hepatitis B model with Gaussian uncertainties using extended residual power series algorithm(Springer Science and Business Media LLC, 2025-03-07) Qursam Fatima; Mubashir Qayyum; Murad Khan Hassani; Ali AkgülHepatitis B virus (HBV) is a significant global health concern, causing acute and chronic liver diseases, including cirrhosis and hepatocellular carcinoma. This manuscript extends existing mathematical models for HBV by introducing a treatment compartment to improve understanding, diagnosis, and treatment strategies. A stability analysis is conducted for disease-free equilibrium and to address the inherent uncertainties in parameter values, Gaussian fuzzy numbers are incorporated, resulting in a more realistic predictive framework. For solution purposes, the extended residual power series algorithm, which combines the Taylor series with a residual function and an integral transform, is applied. The accuracy of the obtained solutions is assessed by calculating the associated errors. The robustness of the model is further evaluated using r-cut values for lower and upper bounds.A graphical analysis is also performed to examine the influence of different parameters on the solution profiles, enhancing the understanding of disease dynamics. The analysis reveals that the proposed methodology effectively explains the dynamics of epidemic systems and provides new perspectives with potential applications in biology, engineering, and medicine.Öğe Metal chelate based site recognition of ceruloplasmin using molecularly imprinted polymer/cryogel system(Taylor & Francis Group, 2020) Dolak, Ibrahim; Canpolat, Gurbet; Ersöz, Arzu; Say, RıdvanIn 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 nonimprinted 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°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.Öğe Selective separation of cobalt using a new Co(II)-imprinted polymer/cryogel system(2018) Canpolat, GurbetThe aim of the present study was to investigate selective separation and preconcentration of Co(II) ions in aqueous solutions by ion imprinted technique. For this purpose, Co(II)-methacryloylhistidine((MAH)2-Co(II)) complex monomer has been synthesized and polymerized with presence of 2-hydroxyethyl methacrylate (HEMA) followed by flushed out of bonded Co(II) ions from polymer with 5.0 mol*L-1 HNO3. Thus, specific cavities for re-binding of target ions (Co(II)) have been created onto p-HEMA-MAH cryogel column. Prepared metal complex and Co-imprinted polymer/cryogel system have been characterized by FTIR and SEM. The effect of various parameters such as pH, initial concentration, flow rate, ionic strength have been investigated to determine optimal adsorption conditions. The maximum amount of adsorbed Co(II) has found as 106.0 mg*g-1 at pH 8.0 with flow rate of 1 mL*min-1. For selectivity experiments, binding studies were carried out presence of Cu(II) and Ni(II). The k (selectivity coefficient) values have found as 8.9 and 3.8 for Co(II)/Cu(II) and Co(II)/Ni(II) binary mixture, respectively. The reuse of column also has been investigated and there was no significant decrease at adsorption capacity even in consecutive eleven experiments.Öğe Synthesis and characterization of an unsymmetric salicylaldimine ligand derived from 1-(2-aminoethyl) piperazine and investigation of its analytical properties for the extraction and preconcentratıon of some divalent cations(2011) Kılıç, Ahmet; Teğin, İbrahim; Taş, Eşref; Ziyadanoğulları, RecepThe synthetic, structural, spectroscopic and analytical properties of steric hindered Schiff-base ligand [N-(3,5-di-tert-butylsalicylaldimine)-1-(2-Aminoethyl) piperazine (HL)] and its mononuclear Cu(II), Co(II) and Ni(II) complexes are described. The new unsymmetric steric hindered Schiff base ligand containing a donor set of NONO was prepared by the reaction of 1-(2-Aminoethyl) piperazine with 3,5-di-tert-butylsalicylaldehyde. Certain metal complexes of this ligand were synthesized by treating an ethanolic solution of the ligand with an equimolar amount of metal salts. The ligand and its metal complexes were characterized by FT-IR, UV-Vis, 1H NMR, elemental analysis, molar conductivity and magnetic susceptibility techniques. The reaction of this ligand in a 1:2 mole ratio with metal acetate afforded mononuclear metal complexes. The molar conductivity (ΛM) values of the metal complexes of Ni(II), Co(II) and Cu(II) were in the range of 6.4 to 9.8 Ω−1 cm2 mol−1 at room temperature. Preconcentration and separation of Cu2+ from aqueous solution using N-(3,5-di-tert-butylsalicylaldimine)-1-(2-Aminoethyl) piperazine (HL) as a new extractant were studied. The extraction experiments were carried out at various pHs. While Cu2+ showed the highest extractability and selectivity at pH 7.0, extractions of Co2+ and Ni2+ were unsuccessful due to precipitate formation.Öğe Removal of Cadmium and Lead from Aqueous Solution by Calcite(Pol. J. Environ. Stud., 2007) Yavuz, Omer; Guzel, Remziye; Aydın, Fırat; Tegin, İbrahim; Ziyadanoğulları, RecepThe removal of toxic cadmium(II ) and lead(II ) from aqueous solutions was investigated using calcite, which is inexpensive and widespread over the globe, as the effective inorganic adsorbent. The experimental data of the removal equilibrium were correlated by either the Langmuir or Freundlich equations. Results indicate that the Langmuir model gave a better fit to the experimental data than the Freundlich equation. Maximum adsorption capacities were determined as 18.52 mg/g Cd and 19.92 mg/g Pb for natural calcite at 25°C, respectively.Öğe Synthesis, structural characterization of new macrocyclic schiff base derived from 1, 6-bis (2-formylphenyl) hexane and 2, 6-diaminopyridine and its metal complexes(CSIR, 2008) İlhan, Salih; Temel, Hamdi; Sunkur, Murat; Tegin İbrahimA macrocyclic ligand has been synthesized by reaction of 2,6-diaminopyridine and 1,6-bis(2-formylphenyl)hexane. Its complexes with Cu(II), Ni(II), Pb(II), Zn(II), Cd(II) and La(III) have been synthesized by the reaction of ligand and Cu(ClO₄)₂.6H₂O, Ni(ClO₄)₂.6H₂O, Pb(ClO₄)₂.6H₂O, Zn(ClO₄)₂.6H₂O, Cd(ClO₄)₂.6H₂O and La(ClO₄)₃.6H₂O, respectively. The ligand and its metal complexes have been characterized. All complexes are diamagnetic while the Cu(II) complex is binuclear.Öğe Synthesis and characterization of an unsymmetric salicylaldimine ligand derived from 1-(2-Aminoethyl) piperazine and Investigation of Its analytical properties for the extraction and preconcentratıon of some divalent cations(J. Iran. Chem. Soc., 2011) Kılıç, AhmetThe synthetic, structural, spectroscopic and analytical properties of steric hindered Schiff-base ligand [N-(3,5-di-tert-butylsalicylaldimine)-1-(2-Aminoethyl) piperazine (HL)] and its mononuclear Cu(II), Co(II) and Ni(II) complexes are described. The new unsymmetric steric hindered Schiff base ligand containing a donor set of NONO was prepared by the reaction of 1-(2-Aminoethyl) piperazine with 3,5-di-tert-butylsalicylaldehyde. Certain metal complexes of this ligand were synthesized by treating an ethanolic solution of the ligand with an equimolar amount of metal salts. The ligand and its metal complexes were characterized by FT-IR, UV-Vis, 1H NMR, elemental analysis, molar conductivity and magnetic susceptibility techniques. The reaction of this ligand in a 1:2 mole ratio with metal acetate afforded mononuclear metal complexes. The molar conductivity (ΛM) values of the metal complexes of Ni(II), Co(II) and Cu(II) were in the range of 6.4 to 9.8 Ω−1 cm2 mol−1 at room temperature. Preconcentration and separation of Cu2+ from aqueous solution using N-(3,5-di-tert-butylsalicylaldimine)-1-(2-Aminoethyl) piperazine (HL) as a new extractant were studied. The extraction experiments were carried out at various pHs. While Cu2+ showed the highest extractability and selectivity at pH 7.0, extractions of Co2+ and Ni2+ were unsuccessful due to precipitate formation.
