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Öğe Adsorption of Malachite Green from Aqueous Solution Using Hydroxyethyl Starch Hydrogel Improved by Graphene Oxide(Springer, 2022) Onder, Alper; Kivanc, Mehmet Riza; Durmus, Secil; Ilgin, Pinar; Ozay, Hava; Özay, ÖzgürThis study is the first report of the preparation of hydroxyethyl starch (HES) hydrogels rapidly crosslinked with divinyl sulfone in a single step and single pot. To develop the physical and chemical features of hydrogels, Graphene oxide (GO) nanoparticles were combined with the crosslinked HES. In addition to swelling studies, structural characterization of the samples was conducted with a scanning electron microscope (SEM) and transmission electron microscope (TEM), Fourier transform infrared (FTIR) spectroscopy, X-ray diffractometry (XRD), Brunauer-Emmett-Teller (BET) analysis and thermogravimetric analysis (TGA). For the removal of malachite green model dye by GO-HES, the effects of GO content, solution concentration, temperature, contact duration, dosage and pH on varying adsorption features were researched. Additionally, adsorption isotherms, kinetic and thermodynamic systematics were analyzed. The maximum adsorption capacity of GO-HES composite hydrogel was found to be 89.3 mg/g for Langmuir isotherm. The possible adsorption mechanism of the composite hydrogels for malachite green dye involved electrostatic, hydrogen bonding, and pi-pi interactions. In addition to reasonable cost and simple synthesis method, the prepared composite materials have potential use in wastewater treatment as adsorbents for the removal of dye from aqueous solutions due to efficient adsorption capacity.Öğe An innovative approach to use zeolite as crosslinker for synthesis of p(HEMA-co-NIPAM) hydrogel(Springer Wien, 2022) Durmus, Secil; Yilmaz, Betul; Onder, Alper; Ilgin, Pinar; Ozay, Hava; Özay, ÖzgürThis study introduced a modified method to synthesize organic-inorganic hybrid crosslinker based on zeolite. First, zeolite nanoparticles were modified with 3-(aminopropyl)trimethoxysilane. Then, the amine-functionalized zeolite has been reacted with the glycidyl methacrylate via an epoxide ring-opening mechanism. The vinyl-functionalized zeolite was applied as a crosslinking agent to form hydrogel network. A novel temperature-sensitive nanocomposite hydrogel was prepared by crosslinking N-isopropylacrylamide as a comonomer and 2-hydroxyethyl methacrylate as a monomer with free-radical polymerization. Results showed that p(2-hydroxyethyl methacrylate-co-N-isopropylacrylamide)/vinyl-functionalized zeolite nanocomposite hydrogel has a chemically crosslinked and porous network structure. The content of crosslinker and monomers had obvious effects on the swelling ratio of the nanocomposite hydrogel. The temperature and salt-sensitive behavior of the hydrogels are also discussed. We offer a multifunctional crosslinker for preparing sensitive materials that can serve biomedical or environmental applications.Öğe Assessment of release and anticancer effect of innovative pH-responsive and antioxidant-biodegradable hydrogel by using Parthenocissus quinquefolia L. extract as a crosslinker(Elsevier, 2023) Onder, Ferah Comert; Kalin, Sevil; Onder, Alper; Ozay, Hava; Özay, ÖzgürThe level of toxicity in cancer treatment with chemotherapy can negatively affect the treatment process. Therefore, targeted drug delivery systems play an important role in reducing treatment-related toxicities. Hydrogels with three-dimensional networks are being investigated as drug delivery systems due to their unique properties such as swelling capacity, biocompatibility, and bioavailability. Poly(2-hydroxyethyl methacrylate-co- methacrylic acid)/PQ (p(HEMA-co-MAA)/PQ) hydrogel was prepared by redox polymerization method using Parthenocissus quinquefolia L. (PQ) plant extract, known for its anticancer, antioxidant, and antimicrobial properties, as a crosslinker. PQ hydrogels were prepared with various monomer and cross-linker ratios. The p(HEMAco-MAA)/PQ10 (1:1) with a highly porous structure exhibited high swelling behavior. The phenolic content of p (HEMA-co-MAA)/PQ10 (1:1) hydrogel which has been determined to have high in vitro biodegradability at pH 6.5, increased with the amount of PQ extract used as crosslinker. The pH-responsive, antioxidant, biodegradable, and highly porous p(HEMA-co-MAA)/PQ10 (1:1) hydrogel showed higher doxorubicin (Dox) release behavior at pH 6.5. The Dox-loaded p(HEMA-co-MAA)/PQ10 (1:1) hydrogel drug carrier showed its anticancer effect on inhibition of colonies and cell proliferation against breast cancer cell lines. Our findings show that the p(HEMAco-MAA)/PQ10 (1:1) hydrogel using the PQ plant extract as a crosslinker will be significant potential in combination and cancer therapy studies.Öğe Fly ash as catalyst support material in the hydrolysis of ethylenediamine bisborane for hydrogen production: The use of coal-fired power plant waste(Pergamon-Elsevier Science Ltd, 2020) Onder, Alper; Özay, ÖzgürEfficient, low-cost and safe new systems are still needed for the storage and usage of hydrogen energy, which is considered the most important energy source of the future. For this reason, the aim of this study was to prepare Co-0, Ni-0, and Cu-0 composite catalysts with fly ash (FA) formed by combustion of coal in thermal power plants to be used for the dehydrogenation of ethylenediamine bisborane (EDAB) as a hydrogen source. In the hydrolysis reactions of EDAB, parameters such as metal type, catalyst concentration, temperature, and EDAB concentration were investigated. The FA-Cu-0 composite catalyst was determined to be an effective catalyst system for hydrogen production by hydrolysis of EDAB from among the FA-M-0 composite catalysts. Besides, FA can be used as an effective support material in order to prevent agglomeration of metal particles. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.Öğe Graphene nanoplate incorporated Gelatin/poly(2-(Acryloyloxy)ethyl trimethylammonium chloride) composites hydrogel for highly effective removal of Alizarin Red S from aqueous solution(Springer, 2022) Ozsoy, Fatma; Ozdilek, Batuhan; Onder, Alper; Ilgin, Pinar; Ozay, Hava; Özay, ÖzgürThe increasing water pollution day by day has increased the importance of developing new adsorbent materials. In this study, composite hydrogel containing gelatin, [2-(Acryloyloxy)ethyl] trimethylammonium chloride (AETAC) and Graphene Nanoplate (GNPt) was developed as an adsorbent for the removal of dyes from wastewater. Fourier Transform Infrared Spectrophotometer, Scanning Electron Microscope, X-Ray Diffractometer results confirmed the crosslinked polymer structure of Gelatin/p(AETAC)/GNPt composite hydrogel (Gel 5). In addition, equilibrium swelling ratio, which is a parameter affecting the adsorption behavior, was 48.22 g(water) /g(gel). The adsorption behavior of Alizarin Red S anionic dyestuff on composite hydrogel from aqueous solutions was investigated under various experimental conditions such as initial dye concentration of solution, amount of adsorbent, contact time, pH of solution, temperature of solution. ARS dye adsorption on composite hydrogel is consistent with Pseudo-Second-Order kinetic model and Langmuir isotherm with max adsorption capacity of 649.35 mg/g. The composite hydrogel with high mechanical strength has high dye removal ability in the ranging pH from 4 to 8. Therefore, it can be said that Gelatin/p(AETAC)/GNPt composite hydrogel has a substantial potential for the removal of anionic dyes from wastewater in a wide pH range.Öğe Novel benzothiazole/benzothiazole thiazolidine-2,4-dione derivatives as potential FOXM1 inhibitors: In silico, synthesis, and in vitro studies(Wiley-V C H Verlag Gmbh, 2024) Abusharkh, Khaled A. N.; Onder, Ferah Comert; Cinar, Venhar; Onder, Alper; Sikik, Merve; Hamurcu, Zuhal; Ozpolat, BulentThe oncogenic transcription factor FOXM1 overexpressed in breast and other solid cancers, is a key driver of tumor growth and progression through complex interactions, making it an attractive molecular target for the development of targeted therapies. Despite the availability of small-molecule inhibitors, their limited specificity, potency, and efficacy hinder clinical translation. To identify effective FOXM1 inhibitors, we synthesized novel benzothiazole derivatives (KC10-KC13) and benzothiazole hybrids with thiazolidine-2,4-dione (KC21-KC36). These compounds were evaluated for FOXM1 inhibition. Molecular docking and molecular dynamics simulation analysis revealed their binding patterns and affinities for the FOXM1-DNA binding domain. The interactions with key amino acids such as Asn283, His287, and Arg286, crucial for FOXM1 inhibition, have been determined with the synthesized compounds. Additionally, the molecular modeling study indicated that KC12, KC21, and KC30 aligned structurally and interacted similarly to the reference compound FDI-6. In vitro studies with the MDA-MB-231 breast cancer cell line demonstrated that KC12, KC21, and KC30 significantly inhibited FOXM1, showing greater potency than FDI-6, with IC50 values of 6.13, 10.77, and 12.86 mu M, respectively, versus 20.79 mu M for FDI-6. Our findings suggest that KC12, KC21, and KC30 exhibit strong activity as FOXM1 inhibitors and may be suitable for in vivo animal studies. The oncogenic transcription factor FOXM1, overexpressed in breast and other cancers, drives tumor growth, making it a key therapeutic target, but existing inhibitors lack specificity and potency. Among the synthesized benzothiazole derivatives (KC10-KC13) and benzothiazole-thiazolidine-2,4-dione hybrids (KC21-KC36), KC12, KC21, and KC30 significantly inhibited FOXM1 in MDA-MB-231 cells at lower concentrations compared to FDI-6. imageÖğe Novel Dibenzoazepine-Substituted Triazole Hybrids as Cholinesterase and Carbonic Anhydrase Inhibitors and Anticancer Agents: Synthesis, Characterization, Biological Evaluation, and In Silico Studies(Amer Chemical Soc, 2024) Erdogan, Musa; Onder, Alper; Demir, Yeliz; Comert Onder, FerahThe new dibenzoazepine-substituted triazole hybrids (12-20) were designed by molecular hybridization approach and synthesized utilizing the Cu(I)-catalyzed click reaction. The hybrid structures (12-20) were obtained in high yields (74-98%) with a simple two-step synthesis strategy and fully characterized. These compounds were assessed for their influence on various metabolic enzymes including human carbonic anhydrase isoenzymes (hCA I and hCA II), acetylcholinesterase (AChE), and butyrylcholinesterase (BChE). The Ki values for the compounds concerning hCA I, hCA II, AChE, and BChE enzymes were in the ranges 29.94-121.69, 17.72-89.42, 14.09-44.68, and 1.15-48.82 nM, respectively. Compound 13 was 49.70-fold more active than tacrine (standard drug) for BChE and 5.49-fold for AChE. Compound 14 was 4.16-fold more active than acetazolamide (standard drug) for hCA I and 5.79-fold for hCA II. The cytotoxic effects of the synthesized click products were investigated on human triple-negative breast cancer cell lines. The IC50 values of the most effective compounds were calculated between 12.51 +/- 1.92 and 18.07 +/- 2.14 mu M in MDA-MB-231 and BT-549 cells. Molecular docking and ADME predictions were performed. Then, in vitro effective compounds were analyzed by molecular dynamics (MD) simulation and MM/GBSA calculation. Consequently, click products showed good cytotoxicity and inhibition potential on colony formation in cancer cells.Öğe Preparation of antioxidant-biodegradable poly(acrylic acid-co-2-hydroxyethyl methacrylate) hydrogel using rutin as a crosslinker: Drug release and anticancer activity(Elsevier, 2023) Onder, Ferah Comert; Onder, Alper; Ilgin, Pinar; Ozay, Hava; Özay, ÖzgürIt is important to develop drug-release systems that reduce the side effects of chemotherapy drugs, can regulate drug release, and can be designed for a target to keep the quality of life of cancer patients high. In this study, a polyphenol compound rutin was used as a natural crosslinker to prepare poly(acrylic acid-co-2-hydroxyethyl methacrylate)/rutin (RTN hydrogel) as a drug carrier. The swelling behavior, thermal stability, in vitro biode-gradability, and antioxidant activity of this hydrogel were determined. The prepared hydrogel had in vitro biodegradability and antioxidant properties. The maximum doxorubicin (DOX) amount adsorbed by the RTN hydrogel was 32.96 & PLUSMN; 1.83 mg/g. The DOX-loaded RTN hydrogel displayed drug release behavior in normal and cancer cell media. At the same time, the effect of the DOX-loaded hydrogel on triple negative breast cancer (TNBC) cell lines was investigated. Our results show that the RTN hydrogel, prepared using the natural product of rutin as a crosslinker with in vitro biodegradability and antioxidant properties, offers great promise as a high-impact carrier in the drug distribution system.Öğe Removal of dye from aqueous medium with pH-sensitive poly [(2-(acryloyloxy)ethyl]trimethylammonium chloride-co-1-vinyl-2-pyrrolidone] cationic hydrogel(Elsevier Sci Ltd, 2020) Onder, Alper; Ilgin, Pinar; Ozay, Hava; Özay, ÖzgürIn this study, p([2-(acryloyloxy)ethyl]trimethylammonium chloride-co-1-vinyl-2-pyrrolidinone) (p(AETAC-co-NVP) hydrogels containing positive charge in the structure were synthesized for the removal of anionic dyes from the aqueous media. The swelling behaviors affecting the adsorption properties of hydrogels structurally characterized by FTIR, SEM and EDX/mapping analysis were investigated. The effects of pH, dye concentration, adsorbent amount, dissolved anions and temperature on the adsorption of methyl orange (MO) and alizarin red S(AR) from aqueous media using p(AETAC-co-NVP) hydrogels were investigated. Using data obtained in adsorption studies, the Langmuir, Freundlich, Temkin and Dubinin-Radushkevich isotherms and pseudo-first order (PFO), pseudo-second order (PSO), intra-particular diffusion, and Elovich kinetic model analyses were performed. The results showed that the p(AETAC-co-NVP) hydrogel was a good adsorbent for MO and AR anionic dyes and the adsorption process for both dyes complied with the Freundlich isotherm and PSO kinetic model. This situation indicates that the dominant mechanism for the adsorption of MO and AR dyes by the p(AETAC-co-NVP) hydrogel is strong electrostatic interactions and occurs as multilayered adsorption, not only on a planar region. Additionally, to the maximum adsorption values using p(AETAC-co-NVP) hydrogel for MO and AR dyes were reached at pH values of 7.0 and 5.0, respectively. According to all these findings, it can be said that the p (AETAC-co-NVP) hydrogel containing positivelly charged groups is a super adsorbent for adsorption of anionic dyes.Öğe Self-assembled silibinin-containing phosphazene/cystamine hybrid nanospheres as biodagradable dual-drug carriers with improved anticancer activity on a breast cancer cell line(Elsevier, 2023) Ozsoy, Fatma; Onder, Ferah Comert; Ilgin, Pinar; Ozay, Hava; Onder, Alper; Özay, ÖzgürIn this study, pH and redox sensitive biodegradable PPZs@Silibinin polymeric nanospheres were synthesized by the polymerization reaction of Hexachlorocyclotriphosphazene (HCCP), Cystamine dihydrochloride (CA) and the anticancer drug Silibinin as monomers. Later designed as a therapeutic system, this nano drug-carrier was also loaded with Doxorubicin (Dox), a type of cancer drug. As a result, a drug self-delivery system (DSDS) was developed, which had the property of biodegradation in tumor tissues thanks to the redox active disulfide bonds in its structure from pH-sensitive nanospheres containing two anticancer drugs. Biodegradation-associated in vitro release of cancer drug (Dox) from the Dox loaded PPZs@Silibinin nano drug-carrier was performed in the presence of glutathione (GSH) at pH 6.5 and pH 7.4. While 93.06% Dox release was observed in pH 6.5 medium containing 10 mM GSH in 24 h, this value was 56.60% in pH 7.4 + 10 mM GSH medium. In addition, clonogenic analysis and cytotoxicity studies were performed on the MDA-MB-231 cell line to determine the anticancer properties of PPZs@Silibinin loaded with Dox. It was determined that PPZs@Silibinin@Dox nanospheres containing 20.5 nM Dox for 0.75 mu L are highly effective in MDA-MB-231 cells than free Dox.Öğe Synthesis, spectroscopic, and thermal properties of some azomethine complexes of Cu(II), Ni(II), and Pt(II)(Springer, 2012) Turkyilmaz, Murat; Onder, Alper; Baran, YakupFour polydentate azomehines and their mono- and binuclear Pt(II), Cu(II), and Ni(II) complexes were synthesized and characterized. The resulting complexes were characterized by FTIR, magnetic measurements, elemental analysis, conductivity measurements, and thermal analysis. Electronic spectra and magnetic susceptibility measurements sustain the proposed distorted square-planar structures for the copper complexes. The electronic spectra display the characteristic pattern of square-planar stereochemistry for the other complexes. The thermal analyses have evidenced the thermal intervals of stability and also the thermodynamic effects that accompany them. Azomethine complexes have a similar thermal behavior for the selected metal ions. The decomposition processes as water elimination, chloride anion removal as well as degradation of the organic ligands were observed.Öğe Synthesis, spectroscopic, magnetic and thermal properties of copper(II), nickel(II) and iron(II) complexes with some tetradentate ligands: Solvatochromism of iron(II)-L2(Elsevier Science Sa, 2012) Onder, Alper; Turkyilmaz, Murat; Baran, YakupThe tetradentate azomethines were prepared by condensation of 2-piperazin-1-ylethanamine, (3-morpholin-4-ylpropyl)amine with 3-methylthophene-2-carbaldehyde, salicylaldehyde and 1H-imidazole-5-carbaldehyde. The ligands were characterized based on mass, H-1 and C-13 NMR, FTIR, and elemental analyses. New complexes of ligands with copper(II), iron(II) and nickel(II) were synthesized. Metal complexes are reported and characterized by magnetic, conductivity measurements, FTIR, elemental and thermal analyses (TG-DTA). Spectral analyses show that all the ligands behave as neutral tetradentate ligands and bind to the metal via azomethine N, piperazine N, salicylaldehyde O, morpholine O, imidazole N and thiophene S. Results of magnetic measurements and thermal studies show that the geometrical structures of the nickel(II) complexes are square planar while copper(II) and iron(II) are octahedral. The thermal behaviors of these complexes show that the hydrated complexes lose the hydration water molecule in the first step, followed immediately by decomposition of the anion and ligand molecules in subsequent steps. The solvatochromic behavior of the iron(II)-(L)2 complex was investigated using the electronic spectra of 1 x 10 (3) M in four different solvents. The solvatochromism was explained in terms of MLCT transition and solvent characteristics such as polarity, nature and acceptor-donor properties. (C) 2012 Elsevier B.V. All rights reserved.
