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Antioxidant, Antibacterial and UV-Resistant Activities of Undyed and Dyed Wool Fabrics Treated with CuO Nanoparticles
(Amer Scientific Publishers, 2017) Altun, Ozlen; Becenen, Nilgun
For the first time, application to undyed and dyed fabrics and testing of finished fabrics for hydrophobic wettability, antimicrobial activity and UV protection of CuO nanomaterials were investigated. According to absorbance measurements, the CuO nanomaterials demonstrated a significant antioxidant activity. The presence of nanoparticles on fabric surfaces was confirmed by scanning electron microscopy. It was observed that applying CuO nanomaterials to dyed wool rendered the fabric hydrophobic from contact angle measurements. Also, the nano-CuO-impregnated undyed and dyed wool fabrics (100% wool) showed excellent antibacterial activity against Staphylococcus aureus, Escherichia coli and Escherichia coli isolated from pasta. Additionally, UV tests indicated an excellent improvement in the UV-absorbing activity of the CuO nanomaterial-treated undyed and synthetically dyed fabrics.
Applications of TiO2, ZnO and Ag Nanomaterials to Denim Fabric
(Amer Scientific Publishers, 2016) Becenen, Nilgun; Altun, Ozlen
In previous studies much research has reported the determination of applications of TiO2 (rutile and anatase), ZnO and Ag nanomaterials onto various textile surfaces, but in this study for the first time application to denim fabric and testing of the finished fabric for antimicrobial activities of these nanomaterials was investigated. The presence of nanoparticles on dyed denim fabric surfaces was confirmed by Scanning Electron Microscope (SEM). The nanomaterial-impregnated denim fabric (100% cotton) showed significant antibacterial activity against Staphylococcus aureus, Escherichia coli and Escherichia coli isolated from pasta. Additionally, the UV tests indicated excellent improvement in the UV absorbing activity of the TiO2 (rutile and anatase), ZnO and Ag nanomaterial-treated fabrics.
Complexation, thermal and catalytic studies of N-substituted piperazine, morpholine and thiomorpholine with some metal ions
(Pergamon-Elsevier Science Ltd, 2014) Kacan, Mesut; Turkyilmaz, Murat; Karabulut, Ferhat; Altun, Ozlen; Baran, Yakup
Several Cu(II), Pt(II) and Ni(II) complexes of N-substituted, piperazine (NN donor), morpholine (NO donor) and thiomorpholine (NS donor) derivatives were synthesized and their thermal behavior and catalytic activity in epoxidation reaction of cis-diphenylethylene were studied using oxygen sources NaOCl. The coordination compounds of Cu(II), Pt(II) and Ni(II) having general formula [MLCl]Cl, [ML(2)l]Cl-2 or [ML]Cl-2 with tetra coordinated geometry around metal ions have been isolated as solid. All the ligands and complexes were identified by spectroscopic methods and elemental analysis, magnetic measurements, electrical conductance and thermal analysis. A square planer structures have been proposed for all complexes. The thermal stability of the complexes discussed in terms of ligands donor atoms, geometry and central metal ions. The complexes have a similar thermal behavior for the selected metal ions. The thermogravimetric analyses suggest high thermal stability for most complexes followed by thermal decomposition in different steps. The decomposition processes were observed as water elimination, chloride anion removal and degradation of the organic ligands. Catalytic ability of the complexes were examined and found that all the complexes can effectively catalyze the epoxidation of cis-stilbene with NaOCl. (C) 2013 Elsevier B.V. All rights reserved.
Investigation of the wettability and washing, perspiration and rubbing fastness of denim fabric in the presence of some nano-metal oxides and nano-Ag
(Taylor & Francis Ltd, 2018) Becenen, Nilgun; Altun, Ozlen
In this study, we analysed finished denim fabric for hydrophobic wettability, washing, perspiration and rubbing fastness of TiO2 (anatase), CuO, ZnO and Ag nanomaterials. The presence of nanoparticles on dyed denim fabric surfaces was confirmed by Scanning Electron Microscope and EDAX. According to the contact angle, washing, perspiration and rubbing fastness measurements, these nanomaterials were improved surface properties of denim fabric. The coatings made by these nanomaterials increased hydrophilic or hydrophobic properties by changing wetting capability of denim fabric surface. Additionally, nano-metal oxide particles were improved fastness values. The highest contact angle and fastness values were found on denim fabric treated with nano-TiO2 (anatase) and the lowest contact angle and fastness values were found for denim fabric plated with nano-Ag.
The investigation of thermodynamic parameters of kinetic reaction between o-phenylenediamine and gold (III)
(Academic Press Ltd Elsevier Science Ltd, 2007) Altun, Ozlen; Akbas, Halide
A visible spectrophotometric method has been developed for the reaction kinetics of o-phenylenediamine in the presence of gold (III). The method is based on the measurement of the absorbance of the reaction o-phenylenediamine and gold (III). Optimum conditions for the reaction were established as pH 6 at lambda=466 nm. When the reaction kinetic of o-phenylenediamine by gold (III) was investigated, it was observed that the following rate formula was found as In (A/A(0)) = -kt, according to absorbance measurements. The activation energy E-a and Arrhenius constant A were calculated from the Arrhenius equation as 1.009 kJ center dot mol(-1) and 3.46 center dot 10(-2) s(-1), respectively. Other activation thermodynamic parameters, entropy, Delta S (J center dot mol(-1) center dot K-1), enthalpy, Delta H (kJ center dot mol(-1)), Gibbs free energy, Delta G (kJ center dot mol(-1)) and equilibrium constant, K-e were calculated at T = (283.2, 303.2, 323.2, and 343.2) K. The study was exothermic due to the decrease of entropy and was a non-spontaneous process during activation. (c) 2007 Published by Elsevier Ltd.
Kinetic spectrophotometric method for o-phenylenediamine in the presence of gold(III)
(Pergamon-Elsevier Science Ltd, 2007) Altun, Ozlen; Akbas, Halide; Dolen, Emre
From the color developing reactions of o-phenylenediamine oxidizing agent and gold(III), the kinetic reactions between both of them in aquaeous solutions were studied using spectrophotometric and differential method. Light absorbances in the visible spectral range are measured as a function of mole fractions of phenylenediamine at a fixed gold(III) concentration and as a function of mole fraction of gold(III) at a fixed o-phenylenediamine concentration at periodic time internal. In the differential method, which was suggested by van't Hoff, one deals with the actual rates of reactions as determined by measuring the slopes of absorbance-time curves. Optimum condition of the reaction were established as pH 6 at lambda = 466 nm and room temperature. When the oxidation of o-phenylenediamine by gold(III) was investigated, it was observed that the following rate formula and rate constant were found: v = k[Au+3](1/2) [o-phenylenediamine](1/2), k = 2.33 x 10(-2) s(-1) (c) 2006 Elsevier B.V. All rights reserved.
THE Pd(II) COMPLEX INVOLVING A NEW PYROLE-BASED LIGAND: SYNTHESIS, SPECTRAL ANALYSIS, AND ANTIMICROBIAL ACTIVITY
(Soc Chemists Technologists Madeconia, 2022) Boz, Mesut; Tetik, Ovul; Altun, Ozlen
In the current study, firstly, a new pyrrole-based ligand (3,4-(ethylenedimercaptodiacetoxy)-N-(benzyl)-diethyl-2,5-pyrroledicarboxylate (L) was synthesized in the presence of diethyl-N-benzyl-3,4-dihydroxy-1H-pyrrole-2,5-dicarboxylate and 2,2'-(ethane-1,2-diylbis(sulfanediyl))diacetylchloride. Then, the palladium(II) complex of the synthesized ligand was obtained, and its structural features were examined by spectral (HRMS, ESI-MS, UV-Visible, FTIR, H-1 NMR, C-13 NMR, XRD-POWDER, SEM, EDX) and thermogravimetric (TG-DTA) techniques. The spectral and thermal measurements of the ligand and its Pd(II) complex show that the ligand is coordinated to the Pd2+ ion. Antimicrobial activities of both the ligand and its palladium complex were examined. It was determined that whereas the ligand indicated modest antimicrobial activity against Staphylococcus aureus and Candida albicans at a concentration of 6.25 mu g/ml, the palladium complex was significantly effective against C. albicans at a concentration of 6.25 mu g/ml.
Practical Synthesis of Pioglitazone: Ligand Substitution Reaction With Oxido Vanadium(IV) and Biological Activity
(Taylor & Francis Inc, 2013) Altun, Ozlen; Kucuktepe, Caner; Yoruk, Ozan; Feyizoglu, Adilhan
The authors performed two types of experiments: the reduction of 5-{4-[2-(5-ethyl-2-pyridyl)etoxy]benzilidine}-24- thiazolidinedione to pioglitazone (5-{4-[2-(5-ethyl-2-pyridyl) etoxy]benzil}-24-thiazolidinedione) with magnesium/methanol and the synthesis of an oxidovanadium(IV) complex of pioglitazone in methanol under refluxing conditions. The structures of pioglitazone and its oxidovanadium(IV) complex were analyzed by using physicochemical and spectroscopic techniques. Comparisons of the spectral measurements of pioglitazone with those of its oxidovanadium(IV) ion complex are useful in determining the atoms of the ligand that are coordinated to the metal ion. In addition, antibacterial and antifungal activities of the complex were studied and the complex is screened against bacteria and fungi.
Pt(II) complex of Schiff base derived from L-phenylalanine and furfuraldehyde in the presence of 8-hydroxyquinoline: Structural analysis, composition of complex and biological activity
(Centre Mersenne Pour Ldition Scientifique Ouverte, 2020) Altun, Ozlen; Kocer, Melike Ozge
In the present study, we synthesized a Schiff base (L-1) derived from L-phenylalanine with furfuraldehyde and its Pt(II) complex ([Pt(L-1) (L-2)]: [Pt(N-(furfuralidene)phenylalanine) (8-hydroxyquinoline)]) in the presence of 8-hydroxyquinoline (L-2). The chemical structures of the synthesized Schiff base and Pt(II) complex were characterized using ESI-MS, UV-Visible, FT-IR, H-1 NMR, C-13 NMR, and powder-XRD spectroscopy. The surface morphologies and elemental composition were determined by SEM and EDX. Thermal analysis was performed with TG-DTA. Mole ratio of Meyer and Job methods were used for the composition of complexes. According to these methods, the ratio [Pt2+] : [L-1 + L-2] was found to be 1 : 1. In addition, the antimicrobial activities of L-1 and the complex showed that the compounds have significant antibacterial and antifungal properties. They also show important cytotoxic effects against the growth of mouse embryo fibroblasts (MEF) and human prostate adenocarcinoma (Du145) cancer cells. L-1, L-2, and the Pt(II) complex also displayed effective antioxidant activity.
Spectral, kinetic and thermodynamic studies of Pd (II) with Schiff base derived from L-asparagine and furfuraldehyde in the presence of 8-hydroxyquinoline
(Elsevier, 2021) Altun, Ozlen; Kocer, Melike Ozge
In this study, a Pd (II) complex of the type [Pd(L-1)(L-2)] (where L-1 : Schiff base derived from L-asparagine and furfuraldehyde; L-2 : 8-hydoxyquinoline) was synthesized and characterised using elemental analysis, magnetic moment, conductivity, ESI-MS, UV-Visible, FT-IR, (1) H NMR, C-13 NMR, XRD, SEM, EDX, and TGDTA. The reaction conditions were determined as pH 7 and lambda = 465 nm. When the reaction kinetics were examined, the rate formula was found to be v = k [Pd-2+][L-1 ](1/2)[L-2](1/2) and k = 2.51 x 10(-3) lmol(-1)s(-1). The activation energy (E-a) and Arrhenius constant (A) were calculated from the Arrhenius equation as 3.107 kJmol(-1) and 5.38 x 10(-5) s(-1), respectively. Thermodynamic parameters, enthalpy, Delta H (kJmol(-1)), entropy, Delta S (Jmol(-1) ), Gibbs free energy, AG (kJmol(-1)) and equilibrium constant, K-e, were determined at temperatures of 293.2, 313.2, 333.2 and 353.2 K. According to the thermodynamic parameters, the reaction was a non-spontaneous process. In addition, catalytic ability of the complex was investigated and it was observed that the complex could effectively catalyse epoxidation of cis-1,2-diphenylethylene with meta-chloroperoxybenzoic acid. (c) 2020 Elsevier B.V. All rights reserved.
Syntheses, Spectroscopic, and Thermal Characterization of Cu(II), Ni(II), and Pt(II) Complexes of Some Tridentate Ligands
(Taylor & Francis Inc, 2013) Turkyilmaz, Murat; Karabulut, Ferhat; Altun, Ozlen; Baran, Yakup
The study emphasized azomethine coordination compounds of Pt(II), Cu(II), and Ni(II) having tetracoordinate geometry around the metal ions with the general formula, [MLCl]Cl, where L, azomethine have been isolated in the solid state. All the ligands were identified by spectroscopic methods and elemental analysis. The synthesized coordination compounds have been characterized by FTIR, magnetic measurements, elemental analysis, electrical conductance, and thermal analysis. Square planar structures have been proposed for the Ni(II) and Pt(II) complexes. Magnetic susceptibility measurements and electronic spectra of the complexes sustain the proposed square planer structures. The complexes thermally stable and this thermal stability is discussed in terms of ligands donor atoms, geometry and central metal ions. Azomethine complexes have a similar thermal behavior for the selected metal ions. The TG analyses suggest high thermal stability for most complexes followed by thermal decomposition in different steps. The decomposition processes were observed as water elimination, chloride anion removal, and degradation of the organic ligands. Supplemental materials are available for this article. Go to the publisher's online edition of Synthesis and Reactivity in Inorganic, Metal-Organic, and Nano-Metal Chemistry to view the supplemental file.
Synthesis and Biological Activity of a New Pt(II) Complex Involving 4-bromo-2,6-bis-hydroxymethyl-phenol and Nicotinamide
(Jihad Daneshgahi, 2022) Altun, Ozlen; Yoruc, Zeliha; Boz, Mesut
In the present study, a Pt(II) complex including 4-Bromo-2,6-bis-hydroxymethylphenol (BBHMP) and nicotinamide (NA) was synthesized and structurally analyzed by using spectral and thermal analysis methods. BBHMP and its Pt(II) complex in the presence of BBHMP and NA were investigated for their antimicrobial, cytotoxicity, gene expression, and antioxidant properties. The antimicrobial activity results showed that the platinum complex displayed a significant effect against Staphylococcus aureus and Candida albicans. The cytotoxicity of BBHMP and platinum complex were determined against human prostate adenocarcinoma (DU145) and breast (MCF7) cancer cell lines by applying the MTT assay. Cytotoxicity results suggested that the Pt(II) complex exhibited moderate cytotoxicity against the growth of these cancer cell lines when compared with the reference drug cisplatin is more effective than free BBHMP and NA. Gene expression results proved that the Pt(II) complex is a special bioactive chemical constituent and potential anticancer agent. The results obtained showed that the complex had highly inhibitory effects on gene expression. In addition, Pt(II) complex also displayed effective antioxidant activity.
Synthesis and Properties of Some Basic Metals and Manganese Salts of cis-1,2-Cyclohexane dicarboxylic Add
(Asian Journal Of Chemistry, 2010) Altun, Ozlen; Turkyilmaz, Murat; Husyinova, Gulara; Cerkezkayabekir, Ayseguel; Feyizoglu, Adilhan
In this work, sodium, potassium, ammonium and manganese salts of cis-1,2-cyclohexane dicarboxylic acid were synthesized. The structural characteristics of these salts were analyzed by thermo graphic and spectro-scopic methods and examined on liver and wheat under the effect of their biological activities. According to these results, they can be used as a micro-fertilizer in the fields Biology and Agriculture.
Synthesis, Spectral Analysis and Antimicrobial Activity of New Pd(II) Complexes Involving 5,6-Dimethylbenzimidazole
(Higher Education Press, 2023) Turkyilmaz, Murat; Donmez, Murat; Altun, Ozlen
In this study, firstly, 3-bromopropanenitrile(2a), ethyl bromoacetate(2b), and 2-bromoethan-1-amine(2c) were added to 5,6-dimethylbenzimidazole(1) and symmetrically-connected N-heterocyclic carbenes(NHC)[(3a-3c)] were synthesized. Then, the NHC precursor compounds were reacted with PdCl2 and Pd(II)-NHC complexes[(4a-4c)] were obtained. The synthesized NHC precursors(3a-3c) and Pd(II)-NHC complexes(4a-4c) were characterized by different spectroscopic methods. The antibacterial activities of these products were measured against bacteria and fungus with the disc diffusion method. Pd(II)-NHC complexes had higher antibacterial activity than the NHC precursors. The synthesized compounds showed antimicrobial activity with different properties from each other. In vitro biological activities of salts and metal complexes on selected bacteria were determined by the broth dilution method based on Clinical and Laboratory Standards Institute guidelines. 1,3-Bis-(2-hydroxyethyl) imidazolinium bromide and 3-(2-ethoxy-2-oxoethyl)-1-(3-aminopropyl)-1H-imidazole-3-ium bromide had activity against Escherichia coli.
Synthesis, spectral analysis, and thermodynamic parameters of gold(III) complex in the presence of 4-bromo-2,6-bis(hydroxymethyl)phenol and m-nitroaniline
(Springer Wien, 2019) Altun, Ozlen; Yoruc, Zeliha
In the present study, we synthesized 4-bromo-2,6-bis(hydroxymethyl)phenol (BBHMP), and a gold(III) complex was synthesized in the presence of BBHMP and m-nitroaniline (m-NA). The synthesized complex was characterized using spectral (mass, UV-Vis, FT-IR, H-1 NMR, C-13 NMR) and thermal measurements (TG-DTA). The results showed that the optimum conditions for the reactions are pH 7, lambda = 412 nm and the mole ratio of BBHMP:m-NA:Au3+ is 1:1:1. The reaction of BBHMP and m-NA with Au(III) was found to be a complexation reaction and one BBHMP molecule and one m-NA molecule react with one Au(III) molecule. Additionally, the equilibrium constant (K), Gibbs free energy (Delta G), enthalpy (Delta H), and entropy (Delta S) were calculated at 298.16 and 313.16 K, respectively. According to the thermodynamic parameters, the reaction was exothermic because of the decrease in entropy and it was a non-spontaneous process. [GRAPHICS] .
Synthesis, spectral analysis, antimicrobial, cytotoxicity, and antioxidant studies of gold(III) complex of caffeine
(Taylor & Francis Ltd, 2019) Altun, Ozlen; Suozer, Mehtap
In the present study, the reactions involving caffeine (CA) and gold(III) were investigated. The synthesized complex was characterized by using mass, UV-visible, FTIR, H-1 and C-13 NMR, and TG-DTA analyses. From these analyses, it is predicted that the complex has the formula [Au(CA)(2)(Cl)(2)]Cl. In addition, antimicrobial, cytotoxicity, and antioxidant activities of the obtained complex were investigated. Investigation of antimicrobial properties demonstrated that the complex has important antibacterial and antifungal activities. The cytotoxic activity of the complex showed potent cytotoxicity against growth of human prostate (Du145), cervix (HeLa), colon (HT29), and breast (MCF7) cancer cells. Additionally, the complex showed significant antioxidant activity.
Synthesis, spectral analysis, stability constants, antioxidant and biological activities of Co (II), Ni (II) and Cu (II) mixed ligand complexes of nicotinamide, theophylline and thiocyanate
(Elsevier Science Bv, 2017) Altun, Ozlen; Suozer, Mehtap
In the present study, transition metal complexes or coordination entities with metal precursors such as Co (II), Ni (II) and Cu (II) of mixed ligands namely, nicotinamide (NA), theophylline (TP) and KSCN in water were synthesized under refiuxing conditions. The optimization of the reactions to obtain the composition of complexes was performed. The structural elucidation of the complexes was undertaken by using physico-chemical and spectroscopic methods (UV/Vis, FT-IR, Mass and XRD) and thermal analysis. The spectral measurements of mixed ligands with the Co (II), Ni (II) and Cu (II) complexes are compared with each other in determining which atoms of the ligand are coordinated to the metal ion. Based on spectral and magnetic moment measurements, all the coordination entities were identified as in distorted octahedral structure and have the form [M(NA)(2)(TP)(2)(SCN)(2)].xH(2)O. In addition, K (stability constant) and AG (Gibbs free energy) values were calculated by using the Babko and Stanley & Turner's methods. Antioxidant, antibacterial and antifungal activities of the complexes were studied. (C) 2017 Elsevier B.V. All rights reserved.

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